Team UV has officially transitioned to Engineering A Future (EAF).
Please click the following link or the above picture to redirect to our new website: Engineering A Future !
Be sure to subscribe to our new website & follow it please!
Team UV has officially transitioned to Engineering A Future (EAF).
Please click the following link or the above picture to redirect to our new website: Engineering A Future !
Be sure to subscribe to our new website & follow it please!
Well, it appears that it has become time at last for Team UV to end its journey. Today marks the 345th day that TeamUV.org has been active and I can guarantee you that every one of us here at Team UV has throughly enjoyed and cherished the 29,676,840 seconds that this blog has been running (at the time of publishing this post). During this time we have had the incredible opportunity to share some of our own research and, far more importantly, help to inspire interest in the STEM fields amongst the general public with visitors from 115 countries for a total of nearly 8,300 views and well over 200 likes from 114 WordPress followers, our email followers, and many others.
This blog has far exceeded our expectations and for that we have all of our family, friends, supporters, and readers to thank. Without all of you, we would have never been able to accomplish what we have over the past year. I have been honored to lead this team and to have the chance to interact with all of you on a daily basis, all-the-while growing with my teammates and watching them progress through the challenges of the last 15+ months of our senior project. I believe that I can speak for all of us when I say that the experience of writing to all of you here at Team UV is not one that any of us will soon forget. These are the kinds of memories that stick with you.
The experience afforded to all of Team UV by sharing with you all over the past year will serve us well in the future as we push onwards and upwards in life and face new challenges, and I sincerely hope that our time here will serve all of you in the same way. From compressible flow regimes to programming Arduinos to biomedical diagnostic tests to 3D-printing makeup to insects with gear-like rear legs, we truly have covered a whole lot of incredibly diverse topics here at Team UV, but we have not even begun to scratch the surface of what the world of engineering has to offer. Part of the beauty of the world of engineering is that it truly is limitless. Boundaries to the engineering mindset do not exist and physical barriers to what engineers can do simply serve as challenges for scientists and engineers alike to accept. We hope that we have begun to shed some light on this reality and on the opportunities available within the STEM fields.
We set out hoping to reach just one person out there and help to inspire them to go on to pursue STEM-related careers or simply just to spend some time everyday thinking scientifically. I personally have heard from numerous people over the past year about how we have made a difference within their lives or the lives of their friends or families. I have also heard similar stories from my teammates, and that is the golden metric.
I am beyond proud of my team and what we have been able to accomplish and look forwards to continue to share with our readers about STEM over at our next project: EAF. For those that do not know, Engineering A Future (EAF) is a website that I originally intended to launch back in December 2012 with the goal of inspiring interest in the STEM fields amongst the general public…sound familiar? After preparing and stockpiling posts for a few short weeks, my Winter Break ended and the Winter 2012 quarter started in at Cal Poly Pomona (CPP) and my plans fell apart. I had become far too busy, did not have any help, and simply put had never done anything like EAF (or TeamUV.org) before. EAF was created with good intentions, but was not planned for properly by me, but I can assure you, that has all changed.
Flash forward three years and EngineeringAFuture.com will be relaunching on Monday (July 13th, 2015). This time the website is ready to go, as is the team. I have spent the past few months preparing EAF for its launch and am excited to cut the ribbon Monday morning. EAF will follow the same idea that TeamUV.org has, but will take it to a whole new level. EAF has been optimized with one goal in mind: to get as many people as humanly possible excited about STEM. Crazy, right? Well I believe that I have the perfect team to do it and that we are more than prepared to hit the ground running, help people to learn, learn (ourselves), and just have fun with it. Most of Team UV will be carrying over to EAF: Abraham, Ketton, and Andrew will all be bringing their massive brains, awesome outlooks, and passion for STEM-blogging and connecting with the community over to EAF. Unfortunately, Ben will not be continuing with us at EAF and so we wave a somber goodbye to a valued team member and friend. But fear not, while we may be losing a teammate, we are also introducing some awesome new features.
First is the style of posting. EAF will be posting three times a week (just like Team UV has been), but this time we will be posting on Monday, Wednesday, and Friday. Posts will go live at 0800 (purely so that our followers who check the site early will already have the content up to read, rather than having to wait around for two hours) and the social media (Facebook, Twitter, and Instagram) sharing of the posts will be sent out at 1000 hours (two hours later). Post categories have been almost completely revamped and the new categories will consist of:
On top of this, the new website is far more aesthetically pleasing, has many cool features and pages, and will hopefully mean a much more awesome experience for our readers and followers. Lastly, we have some very cool ideas in the works for some awesome new types of content that will launch later on down the road. The website is currently having its finishing touches put on with the About EAF page being finished up offline before transferring it to the site this weekend, a few member bio pages being finished up, and the graphical interface being tweaked a little bit more for Monday’s launch.
In closing, we want to thank our readers/supporters/followers for joining us along this journey and sincerely hope that all of you will continue to follow us over at EAF starting Monday! On Monday, a post redirecting our readers to EAF will be published.
Thank you for your time
Sincerely,
Brian
Photo Credit: thumbs.dreamstime.com
Well looks like the time has come to say farewell. This has definitely been a fun ride here at TeamUV.org and I can definitely say I will not forget it. I honestly want to thank everyone who has supported us this entire trip whether it be reading our post, donating, commenting, or any kind of support you have given us. I just hope that we were able to shed some light on all of the interesting items that people just like us have created in the STEM field. We all have learned a lot from the beginning of this project (SHIELA-D) up til the end (DORY) and that experience is something that we will never forget.
You know, anyone can put up an article. But when you put up an article and see that people are coming to the site, reading it, and leaving comments, it is such a great feeling and once again I want to thank everyone who supported us no matter how small or large. As for the “For Now” part, I will be putting up articles for Engineering A Future for a little while so feel free to come, kick back, and read some more articles!
From the coolest guy in the group…..You Rock!
Abe here. Just wanted to thank everyone who donated to our project, read our articles, or simply supported us along the way. We accomplished a lot with this project, visited a lot of places, and even represented our department at the Engineering Project Showcase. More importantly, I am more than pleased with what we learned by tackling this project. I think everyone on the team got a glimpse of what being on a real engineering team was all about and we can now take this experience to industry or wherever we go. I hope that what we have done here inspires you to do something you’re passionate about and give it your all. In closing, I will continue to write for Engineering a Future for the next few months so follow us there!
Goodbye nerd friends. I’ll see you later this month on EAF!
Team UV Crest, representing our principal application (ISR), and our potential future applications (Mine Detection, Underwater Inspection, and Exploration).
It has been quite an adventure writing the posts for this site, I know I have learned a lot, and hopefully you have too. While this blog catered mostly to people interested in the science technology engineering and math fields I did what I could to make it accessible to all. One of the best ways to learn something new is to try and explain it, so thank you for letting me learn by explaining to you.
Hopefully most of you will continue on the Engineering A Future. I will not, my blog writing journey has reached its end here. It was fun while it lasted stay curious and stay creative, always stretch your minds to the limits!
As many of you are aware, we are in the transitioning phase of this website as we close out TeamUV.org and transition to EngineeringAFuture.com over the next two months, so this will be Ketton’s last Open Mind post here at Team UV, but not to fear, there is still one week of posts left here and the same types of articles will be carried over onto EAF (Engineering A Future), so without further ado, please enjoy the following:
We have been yearning for the hoverboard technology ever since it premiered in series like Back to the Future and Real Adventures of Johnny Quest. But, due to the complexity of the underlying technology, no hoverboards have yet been able to accommodate a real person during flight. It has largely been agreed that the future hoverboard’s levitation effect will come from the application of electromagnetic levitation rather than any propulsion. But in addition to the electromagnetism, the new board also uses liquid Nitrogen in some capacity. The new attempt at the hoverboard is called Slide and it can lift itself off the ground and carry a person. Not enough technical details regarding the board of our dreams are available, and the sole source of information is a video released by the Tokyo branch of Lexus, the company behind this invention. The project is a part of the Amazing in Motion campaign by the Lexus company that has produced an 11 foot tall android, a swarm of quadcopters and mannequins performing in Kuala Lumpur.
We see in the video (below) how a young man is getting off from his boring regular board and then moves towards the Slider board. It really seems to be levitating in thin air. It seems to be a remarkable feat of engineering and a long-awaited ride for us. Due to the brand image of Lexus, it is unlikely that it is an edited video. The video is real but to see an actual hoverboard is mesmerizing. I bet there are many technical difficulties to overcome before we can actually see it. There had been an attempt of making a working hoverboard before as Kickstarter attracted the Hendo hoverboard that could levitate and move across a floor of some conductive material to create a secondary field.
The Lexus spokesperson told the media that there won’t be any disclosure of information before the end of the month when the board could be unveiled for the cameras. However, we cannot help but feel suspicious about the whole thing. The electromagnetic levitation requires a particular type of surface to float on. In the video, the guy appears to be doing so on concrete, which doesn’t seem to make sense. Maybe there is a secret to the smoking sides of the hoverboard. They must contribute towards its function in some aspect.
Check out the video below and see what all the fuss is about!
Ferrofluid sculpture. Photo Credit: P.Davis, et al. (FYFD)
Today, Brian will be filling in for Ketton due to last minute scheduling issues, we apologize for the post delay.
Ferrofluids are quite complex fluids that display interesting behavior in the presence of magnetic fields. These ferromagnetic fluids are created through the colloidal suspension of ferromagnetic particles of the nano-scale. What does this all mean? In simpler terms, you essentially take tiny (nano-scale, or on the scale of a nanometer/a billionth of a meter; think the size of the base width of a single strand of DNA) magnetic particles and disperse them homogenously (or evenly) throughout a carrier fluid in a way so that the particles are fully wetted (meaning that the particles surfaces are fully coated by the liquid, without other particles in contact with them).
Once the ferrofluid has been created, the next step is as simple as subjecting the fluid to a magnetic field, at which point the ferrofluid becomes magnetized. As the ferrofluid begins to be affected by the magnetic field, it wants to follow this field and comply with its geometry; basically, the fluid wants to become shaped like the field it is being subjected to, but there is a problem: the fluid has surface tension. Because the fluid has cohesive bonding between liquid molecules, the molecules are very strongly attracted to each other on the molecular scale. This should make sense to you, as when you run your hand through water (for example), you are able to readily cause bulk disturbances (you can split up the water on the large scale), but try as you might, you will not be able to split the water apart on a molecular scale (the smallest you can get water to by hand is tiny visible droplets, which are still collections of a ridiculously large amount of water molecules (on the order of sextillions, or thousands of thousands of thousands of thousands of thousands of thousands of thousands!).
Surface tension. Photo Credit: Wikipedia.org
Because of the aforementioned strong attraction between the liquid molecules, fully immersed liquid molecules are pulled on by other molecules in all directions, as shown above in the picture. However, the molecules on the surface are only pulled on by molecules around and below (but not above) them, leading to a breach in the equilibrium and causing the water to be pulled in the direction of the rest of the water (hence the curved water surface exhibited in the above diagram). So, armed with this knowledge of how surface tension works, we can revisit the ferrofluids and figure out what is going on.
Ferrofluid and magnet, separated by glass. CLICK TO EXPAND TO SEE THE SPIKES BETTER! Photo Credit: Wikipedia.org
The magnetic field wants to push the ferrofluid outwards, but the ferrofluid itself wants to pull itself back inwards towards the liquid base due to the surface tension, all while gravity is also resisting the spike formation (this kind of interaction is explained through the normal field instability). At some point all of these forces equate and the fluid is said to be in equilibrium. The result of this? Really cool looking spikes in the ferrofluid as shown above. This gets even cooler when sculptures are created (as in the top picture) by using shaped bases and manipulating the shape of the magnetic field. It should be noted that art is most definitely not the only application for these fluids; in fact, ferrofluids also find application as: liquid seals around the shafts of spinning hard disks/drives, as a convective heat transfer fluid for wicking away heat in small scale and low gravity application, as an imaging agent in some medical imaging techniques (especially magnetic resonance imaging, MRI), as friction reducing agents, as mass dampers to cancel out vibrations, and even as miniature thrusters for small (nanoscale) sattelites!
So there you have it, another awesome engineering phenomenon! Please tune in Sunday for Ketton’s last Open Mind post and remember to continue following us at EngineeringAFuture.com when Engineering A Future (EAF) launches on Monday, July 13th! Enjoy the video below, created by altering the magnetic field in a ferrofluid sculpture!
As many of you are aware, we are in the transitioning phase of this website as we close out TeamUV.org and transition to EngineeringAFuture.com over the next two months, so this will be Abraham’s last Presentation post here at Team UV, but not to fear, there are still two months of posts left here and the same types of articles will be carried over onto EAF (Engineering A Future), so without further ado, please enjoy the following:
Have you ever heard of Ultrasonic Melt Treatment? Me neither but I did some research and found some pretty interesting things. Ultrasonic Melt Treatment (UST) is essentially the addition of high frequency acoustic waves to a liquid melt of a metal (typically aluminum) to induce acoustic cavitation. Please note that acoustic cavitation is essential. The acoustic waves introduced into the melt have to be at a high enough amplitude and frequency to alternate pressure above the cavitation threshold to create cavities in the melt. Essentially what is happening is the rapid formation and collapse of bubbles in the melt which can have some beneficial effects before, after, and during solidification. The acoustic cavitation is said to activate the melt which means that it will accelerate diffusion, wetting, dissolution, and dispersion which will directly affect degassing, solidification, and refining of metallic alloys. Now if you’re into metallurgy this all sounds incredibly interesting, but if you’re not I will try to explain what each of these mean.
Degassing is one of the primary uses of UST in which the concentration of a certain gas will be lowered in the melt. In light aluminum alloys, acoustic cavitation will cause the growth of fine bubbles in the melt on the surface of non-wettable oxides. As a result, cavitation will cause direct diffusion of hydrogen into the bubbles from the melt. Acoustic flow will assist in floating these bubbles to the surface and out of the melt. The benefits of degassing are that lower porosities can be achieved and thus higher densities in the final material. It has also been found that lowering the concentration of hydrogen in aluminum alloys will raise the ultimate tensile strength and ductility of the material. It is noteworthy that one study concluded that UST is the best amongst other commercial degassing techniques in terms of effectiveness in degassing and in time of treatment.
Degassing of oil using UST is similar to the UST process in liquid metal melts. Photo Credit: hielscher.com
Melts are usually cleaned of inclusions before final treatment. Aluminum melts usually use mesh filters but in order to filter out very fine particulates, multiple layers of successive filters need to be used. This is often not allowed because of the restriction of capillary action of the liquid melt through the filters, however with the use of UST during filtration, a sonocapillary effect is produced. This sonocapillary effect is caused by the cavitation field that is formed which allows for the melt to freely pass through the multiple layers and disperse unwanted oxides.
Ceramic filters. Photo Credit: induceramic.com
One of the most important benefits of UST is that it produces non-dendritic structures during solidification. A dendrite is a branched tree-like structure that grows during solidification of liquid metals (fun fact: dendritic solidification is actually what is behind the unique shape of snowflakes!). As mentioned earlier, acoustic cavitation allows for the wetting of non-metallic impurities in the melt and these become sites for nucleation (aka the start of solidification). Because these nucleation sites are ahead of the solidification front, there is no growth of dendritic structures.
As non-dendritic solidification occurs, the grain becomes only a fraction of the matrix structure so there is refinement in grain size. It is important to note that grain size is only a function of cooling rate in these conditions, therefore this method of refinement is applicable to all metallic materials. One of the major benefits of materials with non-dendritic structures in Al-Si-Mg systems is that they are able to deform very easily at a semi-solid temperature ranges. Essentially what this does is allows the grains to rotate and slide relative to each other without the interference of the dendritic braches. This can dramatically improve mold filling by lowering the viscosity. The apparent viscosity of non-dendritic melts at the semi-solid temperature range is lower than that of the regular melts and is comparable to that of olive oil, at least for aluminum.
Overall there are many benefits to Ultrasonic Melt Treatment in aluminum alloys such as degassing, refinement of grain size, and filtration. Although UST has only been extensively studied in non-ferrous alloys, recent research has been done on its effects in low-carbon steels and even epoxy based nanocomposites. In all cases it is the acoustic cavitation, duration of the treatment, and force of frequency that dictate the effectiveness of UST. Hopefully this taught you a little bit about UST. For more info, please refer to the paper by Eskin, G.I. “Broad prospects for commercial application of the ultrasonic (cavitation) melt treatment of light alloys”.
3D printed glass. Photo Credit: 3DPrint.com
As many of you are aware, we are in the transitioning phase of this website as we close out TeamUV.org and transition to EngineeringAFuture.com over the next two months, so this will be Abraham’s last Well Read post here at Team UV, but not to fear, there are still two months of posts left here and the same types of articles will be carried over onto EAF (Engineering A Future), so without further ado, please enjoy the following:
Over the last few years 3D printing has gone from a obscure manufacturing process into a mainstream solution for everyday problems. The reason for this transition is mainly due to the types of materials that are able to be extruded out of a hot-end of a 3D printer. PLS was first used because of low melting point but with advances in hotend technology, materials such as ABS, nylon, polycarbonate, PEEK and more can be used in additive manufacturing. The more materials you have to work with, the more applications your product can have and that’s exactly the beauty of 3D printing. It is amazing for prototyping and making unique parts that you cannot find anywhere else.
The average 3D printer’s extruders have a temperature range of about 180-325°C, however, this limits the types of materials that can be used. A small Israeli company called Micron3DP has been experimenting with glass as a medium for 3D printers and (as of today) has announced that it has had a successful test using molten glass! Now if you know a little about materials, you know that glass and ceramics have extremely high melting points which means using them as a medium for a 3D printer requires an extremely hot extruder. And that’s exactly what they did.
Micron3DP’s tests were done using “soft” glass at a melting point of 850 °C and borosilicate glass at a melting point of 1640 °C using an innovative way of 3D printing in an extremely hot extruder. The process is analogous to that of printing with molten thermoplastics on a Cartesian based machine, one layer is laid down and cooled rapidly before the next layer is set down.
3D printed glass shapes. Photo Credit: 3DPrintingIndustry.com
If you have ever 3D printed anything, you know how empowering it feels when you are able to create exactly what you want and use it immediately. Soon you can add glass to your arsenal and you will be an unstoppable creative force. Glass has very unique optical, corrosion resistant, and temperature resistant properties and this new technology and process will hopefully harness the power of glass for use in the medical industry, aerospace industry, and even the art industry. Now this breakthrough is so recent that as of June 22, 2015 (yesterday) the company is still seeking investors to help them further the technology. If you want to get started on the 3D printing game, here’s how you can make your own 3D printer for cheap:
http://www.instructables.com/id/Chimera-60-DLP-resin-3d-printer/?ALLSTEPS
For more updates on glass 3D printers, visit Micron3DP’s website here: http://micron3dp.com/
Charcoal barbecue. Photo Credit: green.funtimesguide.com
Summer is here and with it brings barbecuing season. While the average charcoal BBQ may seem like a pretty simple appliance there is some solid engineering behind its design.
First let’s look at the charcoal briquettes. An engineer took chunks of wood and organic matter and heated it up in the absence of oxygen to produce an energy dense fuel that is fairly clean burning. This process is called pyrolysis and it removes all the moisture and fumes so that the avid BBQ enthusiast will be able to cook their food without coating it in a black smoke of tiny particles.
The BBQ itself is designed to control the combustion process. By opening and closing vents the user is able to regulate the flow of oxygen to the fuel. This directly affects the combustion rate, the rate at which energy is released in the form of heat.
And, as with any cooking process, heat transfer is an important consideration. When the coals are glowing hot they are emitting a lot of their heat as radiation. Radiation requires a direct line of sight and this is what causes one side of your food to get a nice sear on it before you flip it. When the lid to the BBQ is closed the air inside heats up and this allow for some natural convection, heat transfer from the hot air moved by its change in buoyancy (hot air rises). There is also some conduction, from relatively still hot air and the heated metal components that compose the grill (not to mention conduction through the food itself). Each one of these modes of heat transfer provide a different aspect to the grilling process. Radiation causes the sear, conduction is responsible for the grill marks and convection is responsible for the even heating and temperature of the food.
A deeper understanding of any process can lead to better results and engineering gives perspective into many of these processes. As far as grilling goes most of it can be picked up from experiences, but isn’t it more fun to know why these things happen! Happy Father’s Day to all the dads out there, no matter who does the grilling!
Ball bearings and technical drawings. Photo Credit: amanoverseas.com
Creativity is a huge part of being an innovative engineer. Thinking outside of the box it what has allowed the human race to advance their science and technology to the levels that we see today. While there are a few exceptions most of the engineering courses taken to receive the final degree focus on building a foundation of knowledge. These classes are designed to give a future engineer a solid base to develop ideas from. Creativity is a difficult thing to teach because it comes to everyone in a different way. Here are a few things that I do to help me become more creative.
The biggest thing, at least for me, is that I keep an idea notebook. It is just a small composition notebook that usually remains in my backpack, but when ever I see something that is frustrating or looks like it could be improved I jot it down. This way I have a list of problems that need solving.
Another thing for me is staying in touch with the advancements in technology by reading science blogs and sometimes the journal articles that they refer to. This keeps me learning and stretching my mind into new areas. Some of these new ideas I can tie to the list of problems that need solving and then I can start designing as system that would solve this problem.
Practicing the creative process is one of the best ways to get better at it. By seeing a problem and then attempting to design a system, either as a thought exercise or on paper, more problems come up, which in turn need solving. By going through this process, solving problems, learning new things, applying these things to existing problems, new and innovative solutions arise.
This is the method that I use to come up with new ideas and inject creativity into my work. Please feel free to comment with methods that you use. Everyone’s mind works a little differently and there are so many different ways to find inspiration.
2012 ROUSH Stage 3 Mustang. Photo Credit:premiumphotoshop.com
Friction is one of the most important and unappreciated forces in nature. It is the reason cars’ tires grip the road and handle turns while remaining in control. It is also one of the major reasons your car’s gas millage isn’t what it could be. What if there was a way to keep the helpful aspects of friction while removing the bad ones.
The oil in your car serves as a lubrication system which reduces friction quite a lot by coming between two surfaces that are rubbing together. This system allows cars to have long lives without wearing out, and gives pretty good gas millage. But what if there was a way to totally eliminate friction so that cars could travel much farther on a single gallon of gas and would last much longer without costly maintenance.
To create a system with almost no friction the fundamental mechanics behind friction must be understood. On a large scale friction is caused by tiny ridges in the surface of one material grabbing on to ridges in the other. This has been known for a while but researchers have just found a way to understand what’s happening at an atomic level.
They created a surface of charged ions then shot a laser over the surface. The charge in the ions refracted the laser in ways that allowed the researchers to measure the forces involved in friction on an atom by atom basis. This system was only conceived a few years ago and it give researchers a powerful tool in the hunt for practically friction free surfaces.
A more technical and in depth discussion of this research can be found here: http://www.nature.com/news/friction-of-a-single-atom-measured-with-light-1.17698
Photo Credit: tiesteach.org
As many of you are aware, we are in the transitioning phase of this website as we close out TeamUV.org and transition to EngineeringAFuture.com over the next two months, so this will be Andrew’s last Open Mind post here at Team UV, but not to fear, there are still two months of posts left here and the same types of articles will be carried over onto EAF (Engineering A Future), so without further ado, please enjoy the following:
Last week, I had one of the best educational experiences of my life: a whole day of teaching 6th graders about STEM (Science, Technology, Engineering, and Math)! My lovely girlfriend is a 6th grade, Math and Science teacher and was constantly asked by her students as to when I would visit her class. With the build of DORY in full swing and wrapping up my undergraduate degree, I just couldn’t make time for a visit during the school year. In the last few months, my interest in teaching has grown, especially teaching about science, technology, and engineering. I knew I would take the opportunity to speak to her kiddos the first chance I could get.
A self-balancing wing my controls team made for class.
My girlfriend and I made plans for me to visit the second to last day of their school year. Her kids and I couldn’t be more excited. I made a presentation about STEM and how it applies to our everyday lives. I appealed to their interests by highlighting: famous people and how they use technology, popular electronics and how they wouldn’t be around without STEM, and popular social apps and how they came to existence using STEM. I also showed them famous celebrity engineers such as Ashton Kutcher, Rowan Atkinson, and Michael Gambon. I then continued to show them projects I worked on in my undergrad such as an obstacle avoiding cart and DORY, as well as a live demonstration of a self-balancing wing. They had so many questions with some that showed real engineering intuition. Seeing the excitement in their eyes and the “light bulbs” turn on was a fulfilling moment for me.
Homopolar Motor. Photo Credit: yourepeat.com
At the end of my presentation, I gave them a little background on electrical motors and brought materials to help them make their first simple motor. With a couple of magnets, a battery, copper wire, and a bit of patience they all made a homopolar motor. One team even had their motor spin for 14 minutes before the wire fell off. We even had time to make paper bridges which turned into a very competitive activity!
Paper bridge. Photo Credit: tallbridgeguy.com
Although the day was filled with laughter and excitement, it didn’t come easy! Often times we (meaning my girlfriend!) would have to correct the kids when they would get too roudy or speak out of turn. By the end of the day, we were both so exhausted. I have a new appreciation for middle school teachers and am glad I had the chance to try out the position. It is one difficult career! Teaching 11 year olds may not be in my future, but teaching STEM classes could definitely be!
Until next time…
Homopolar motor. Photo Credit: leventsakar.net
Electric motors are used in many applications from robotics to children’s toys. Although many of these motors are DC motors, Homopolar motors are the simplest of motors and are easy to show students in a classroom setting. All it takes to build your first simple motor are three common materials you can probably find around the house: copper wire, a AA battery, and neodymium magnets.
Common heart shaped approach. Photo Credit: electronics-micros.com
Constructing the motor is simple but getting it to work can take trial and error as well as a bit of patience. Here’s how to do it:
1) Attach the magnet to the negative side of the battery.
2) Strip the copper wire completely or for safety, in the middle and at the two ends.
3) Bend the wire so that one end touches the positive terminal and the other end touches the magnet. A common approach is a heart shaped wire for better stability.
4) Watch: As the copper wire touches the magnet, the wire will begin to spin.
Current (blue) flows from the positive terminal to the magnet at the negative terminal. The current flows in the presence of a magnetic field (red). This causes a force perpendicular to those directions (in the page on the left of the battery and out of the page to the right of the battery). This force causes the wire to spin. Photo Credit: Physics Central
How does it work? Well the theory can get as detailed as you want it to be but to keeps things simple, I will explain the homopolar motor briefly. The copper wire connects the positive terminal to the magnet at the negative terminal. This completes the circuit, allowing current to flow through the circuit (and the wire). Due to the magnet, the current is flowing in the presence of a magnetic field around the battery. When current flows in a magnetic field, it will experience a force called the Lorentz force. This force acts perpendicular to the magnetic field and the flow of the current (and the wire). Consequently, the perpendicular force pushes the wire around the battery.
Once you get a working motor, you can change the shape of the wire to any shape you want! Have fun!
Until next time…
A big thank you to Mr. Russ Neff and the rest of the team over at Bandel Manufacturing for donating the materials and lending the tools necessary for us to shape the body of our underwater vehicle! A few pictures of the process of building the body to our design are included below:
Body at the end of fiberglassing (top) and testing the fiberglass for leaks in an extremely dirty pool that has since been thoroughly cleaned (bottom).
Once again, we thank Bandel Manufacturing as we could not have created the body of our vehicle without you. For more on Bandel Manufacturing, please click this link to their website or visit our Sponsors & Donations page to find the link there.
As many of you are aware, we are in the transitioning phase of this website as we close out TeamUV.org and transition to EngineeringAFuture.com over the next two months, so this will be my last Presentation post here at Team UV, but not to fear, there are still two months of posts left here and the same types of articles will be carried over onto EAF (Engineering A Future), so without further ado, please enjoy the following:
Tracking tags are used to gather data that concerning the behavior of whatever they are attached to. Often times you will see these tags attached to underwater creatures in order to gather large amounts of important information regarding the migratory patterns, mating behavior, predator-prey relationships, hunting/feeding grounds, social behavior, and feeding behavior of sea (as well as other) creatures, just to name a few parameters.
As you can probably imagine, from an electro-mechanical standpoint, these devices must be very well designed and quite technologically advanced in order to be able to gather all of this information through logging positions, orientations, accelerations, temperatures, video, perhaps audio, and so on and so on. On top of this, the power supply must be capable of lasting a very long time so as to enable the data to be collected continuously without a battery change; either that or the device must be able to recharge itself (i.e. solar recharging), which would of course mean gambling on how much time the creature spends near or on the ocean’s surface where the sun can recharge the device. The device must also be attachable in a way that will keep the device in place for a long time without irritating the creature. Vibrations must be controlled so as to not irritate the creature or skew the data and interfere with the sensors, thermal management must be sufficient to not only protect the on-board electronics, but also to not provide discomfort to the animal, the device must be able to withstand impacts and the wear & tear of daily routines, and the device must not interfere with the creature’s behavior in any way. Combine all this with the fact that the device must be waterproofed, often to great depths, without interfering with the sending and receiving of signals, and you begin to see the formation of a pretty hefty problem statement. And oh yeah, we can’t forget that at some point the researcher must be able to get the data (and hopefully the device) back! And lastly, according to your boss, the design must be complete and ready for prototyping by noon Friday and you have a $30 budget!
Theses kind of issues represent the same types of issues that mechanical (and other) engineers must deal with on every project they work on; as a matter of fact, the issues above share a great deal of similarity to many of the issues we had to design for in our underwater vehicle! (except that we had much, much more to design for since we were designing an entire vehicle, so we could rather equate the amount of issues above to those we had to design for for each of our 7+ subsystems!) This provides the background for an excellent conclusion and underlying theme in the world of engineering in general (and mechanical engineering in particular): You cannot design for everything.
Uh oh, does this mean that mechanical engineers are not putting enough work into their designs? That they are being negligent? No, of course not, this is just a simple fact. As much as we might want to think it, the reality is that no design is perfect. As we have demonstrated time and time again here on TeamUV.org, mechanical engineering covers what is essentially an infinite amount of topics, and thus mechanical engineering projects require an infinite amount of considerations. It is humanly impossible to design for everything, because the engineer cannot think of everything. So what do we do instead? We pour ourselves into our work and give the project 150% of our all and do everything we can to consider as many things as we can, and then…we accept the fact that we could not have possibly considered everything, come up with a contingency plan for when (not if) an unforeseen issue arises, and we go back to work.
So what does all of this have to do with tagging marine life? Am I just getting sidetracked? Nope, the reason I am choosing to talk about these things in this context is that this is exactly what has happened with these wildlife tracking tags. The engineers who created these tags did not spend enough time on one crucial detail that may have been seen as a relatively minor issue at the time, but which may have profound consequences regarding the validity of the data gathered and the well-being of the creatures themselves. What is this parameter that was not given enough attention? Drag.
Loggerhead sea turtle tracked with satellite transmitter. Photo Credit: Jim Abernethy (NMFS)
As many of you are aware, drag is essentially resistance to movement through a fluid. Underwater creatures are often streamlined very well because nature is the ultimate engineer and underwater creatures have been optimized for their lifestyle through generations of natural selection. When you attach a bulky electromechanical device to a creature that has been streamlined for the optimal results in its environment, it can have a disturbing effect on the behavior of said creature. Go figure. In fact, as researchers at the National Oceanic and Atmospheric Administration Pacific Islands Fisheries Science Center in Hawaii have found that the disturbance to the fluid flow over the creature caused by the presence of these devices is resulting in increased drag anywhere in the range from 5-100% depending on turtle size and age. This in turn translates to slower speeds for the turtles, lower accelerations, decreased maneuverability, and possibly even behavioral changes due to some unforeseen psychological or emotional effects on the turtles. As a final segue, this in turn can lead to turtles behaving radically differently with regards to patterns, travels, social behavior, etc. that could mean receiving skewed or otherwise invalidated data, as well as a possible decrease in the turtles’ psychological and even physical well-being.
As seen in the video, in this fascinating study, these researchers are studying these disturbances are using some pretty innovative means to do it. The researchers are using the bodies of turtles that deceased from natural causes to form molds to create fiberglass sea turtle bodies of various sizes, which can then be analyzed in low-speed wind tunnels to identify and quantify the flow disturbances caused by these devices. This is an excellent example of one of the major job roles for scientists and engineers: analyzing an issue that was perhaps not considered, not understood, or possibly even simply not known at all to be an issue beforehand in order to gain a better understanding of the issue and then remedy the issue by developing more polished solutions.
One would only wonder why the tail fins were not taken into account in the model, as even though the disturbance is topside and the fins are located on the bottom of the body, with that large of a disturbance upstream, the flow about the tail fins would absolutely be effected in some way by flow separation and subsequent recirculation about the aft portion of the body. Oh well, moral of the story: it is impossible to account for everything, and sometimes it may even come down to cost-savings, ease of design, manufacture, or analysis, or even just simply deadlines. So what do we do? We put our best foot forward, give it our all, be prepared for the imminent issues down range, hope for the best, and to reiterate, we never give anything less than our all to a project for reasons of pride, protecting our reputation as engineers or scientists, and ultimately to do our best in the name of science and engineering.
Please come back Sunday for my last Open Mine post on TeamUV.org! For more info on the above research, click here.
Different ear configurations on different species of bats. Photo Credit: Rolf Mueller (research.vt.edu)
As many of you are aware, we are in the transitioning phase of this website as we close out TeamUV.org and transition to EngineeringAFuture.com over the next two months, so this will be my last Well Read post here at Team UV, but not to fear, there are still two months of posts left here and the same types of articles will be carried over onto EAF (Engineering A Future), so without further ado, please enjoy the following:
Have you ever heard the expression that someone is “as blind as a bat”? Well this expression is not entirely accurate as no species of bats are actually blind; having said this, bats do have horrible eyesight, forcing them to rely on a different way to get around and navigate obstacles. More specifically, bats use SONAR (SOund Navigation And Ranging) in order to navigate the skies. SONAR is essentially exactly what it sounds like; that is, it consists of the use of sound waves to both navigate and to determine the range (distance) to something. As we have discussed before here on Team UV, SONAR consists of both passive and active SONAR, with the former being simply listening to the sound emitted from an object in the environment and the latter being the emitting of sound and then listening for the return echos. Well, as it turns out, bats are kings of both worlds because of the intricate design of their ears and noses.
As seen in the photos above, different species of bats have different configurations of ears in order to navigate the different types of environments that they inhabit, but there are some key features of the ears that are common across almost all bats: grooves, ridges, flaps, and other kinds of ear baffles. All of these features allow the bats to effectively filter out or attenuate some signals while selecting and encoding other signals to make them more easily understandable. All of this is accomplished by the refraction of the signals on the basis of how the sound waves physically interact with the geometry of the ear or by the resonance introduced within the ear due to how the various features of the ear affect the vibrations introduced by the sound wave-ear interaction. In essence these bats are able to reject or suppress all of the irrelevant information stored in the way of sound waves, while selectively highlighting all of the relevant information that they require to be able to acrobatically maneuver through their environment with ease. But wait, there’s more! Bats can actively adjust their ear configuration by deforming their ears in order to constantly change how they filter information and what information they filter. To take this a step further, bats can do this up to ten times per second, or about three times faster than a human can blink their eyes, allowing these bats to adapt at far less than a moment’s notice!
Bat displaying highly intricate ear design and noseleaves. Photo Credit: Rolf Mueller (research.vt.edu)
Everything discussed so far has focused on passive SONAR abilities, but bats also excel with active SONAR. Why is this the case? Because not only can they deform their ears, they can also deform their noseleaves (leaf-like flaps on their noses) to produce a highly focused SONAR beam and to alter the properties of that beam. This translates to the bats being capable of being selective both on the emitting and receiving ends, making them extremely efficient at utilizing their SONAR (not to mention the fact that bats are capable of using far fewer SONAR pulses/beams to navigate than man-made SONAR devices due to this increased efficiency). When you combine this with the fact that they manage to pack all of these biosonar capabilities into such a small package, it is no wonder engineers are studying them to come up with smaller, less power-hungry, more cost-effective, and more efficient SONAR.
To sum up the merits of adapting this biosonar for man-made devices, I will quote Rolf Mueller, the mechanical engineer behind this research:
“The split-second decisions that bats on the wing have to make will often be based only on a very small number of echoes. Based on these few input signals, the bat’s brain is able to make the quick and reliable decisions that swift flight in confined spaces requires,”
You can find more info on this research here: Bat’s biosonar inspires sensing technology research
So there you have it, just another example of how biomimicry or biomimetics is helping to greatly advance the state of science and technology. Please come back Thursday for my last Presentation post on TeamUV.org!
We’ve all been taught that water freezes at 32F (0C) but in actuality water can remain liquid below this temperature, under special conditions. Imagine you’re sitting on your couch after a long day, you’re tired and you’re starting to feel a bit hungry, but the fridge is so far away. Eventually you get hungry enough to get up, go to the fridge, and satisfy your hunger. Water can relate. When the temperature of the water drops below 32F it would prefer to be a solid, but it takes energy to change from a liquid to a solid. As the temperature gets lower the water gets “hungrier”, it wants to be a solid even more, eventually it wants to be a solid enough to overcome the energy barrier, the “walk to the fridge”.
When water wants to become a solid there are two ways it can go. It can either grow on a surface, like condensation on a cool drink or around a dust particle like rain, or, if it has enough energy, it can grow little spheres of solid within the liquid, without the help of a surface. The amount of energy required for this phase transformation is directly related to the amount of surface created. When the transformation is happening on, say the inside surface of a water bottle, the liquid only has to support the area of a dome, the bottle takes care of the rest. When there is no bottle to work with, or the liquid is far from the surface of the bottle, it has to have enough energy to support the surface area of a whole sphere.
If you’re trying to replicate the video above it’s crucial to have very clean water. This means there are no little particles that the water can use to lower the amount of energy required to freeze, it has to save up enough to grow the spheres without any help. The water also needs to be cooled slowly and handled gently because any significant energy changes, thermal or kinetic, can give the water enough energy to start freezing. This is why hitting the bottle will start the reaction. When the bottle is hit, it finally gets the “oomph” it needs to get to the fridge (freeze).
These phenomena (heterogeneous and homogenous nucleation) are also responsible for the famous Mentos and Coke experiment, why bubbles in carbonated drinks seem to come from specific points in the glass, and how engineers make aircraft aluminum strong enough to keep planes in the sky.
Implantable ion drug pump. Photo Credit: http://www.popularmechanics.com
The device shown above is smaller than your finger and it might be the future of devices to treat a fractured spine, pinched nerve, or neurological disorder like epilepsy. Oh…did I mention that it was implantable!?
A team of engineers and medical researchers in Sweden has just designed a pinpoint-accurate implantable drug pump. It delivers medicine with such precision that it requires only 1 percent of the drugs doctors would otherwise need to deploy. As it demonstrated in tests on seven rats, the tiny pump can attach directly to the spine (at the root of a nerve) and inject its medicine molecule by molecule.
The technology is based on a compact but complicated piece of laboratory equipment called an ion pump. To put it simply, as electric current enters the ion pump one electron at a time, medicine is flung out the other end one molecule at a time. One caveat: Because of this setup, only medicines that can be electrically charged can be used with the pump. But that includes more pain medicines than you might think, including morphine and other opiates. In their study, Jonsson and her colleagues experimented with gamma-aminobutyric acid (GABA). This chemical essentially puts the brakes on nerves, reducing pain, but it stops being produced where the nerves are broken. Jonsson’s approach was to use her new drug pump to simply put more GABA back into the broken part of the spine.
With any other drug pump this would be ineffective if not insane—the GABA would simply travel throughout the spine at leisure, wreaking widespread havoc and disrupting the nervous system. But, with the ion pump’s pinpoint precision, Jonsson could inject incredibly small amount of GABA right where they needed it, without the risk of major damage. And it worked. When the scientists gave the test rats a common pain-response test (essentially poking their paws, and seeing how much force was needed for them to retract their arms) the rats with drug-pumps could on average withstand 5 times more force.
Jonsson is emphatic that her medical device is still in the research phase, and a real ion drug pump may be years away. Scaling up the pump to the size required for human needs might not be too big of an issue, but for this experiment, the researchers had their rats implanted with the pumps for three days only. The shell of the pump would likely need to be changed for longer-term use, she says. Regardless, drug pumps like Jonsson’s may hold the promise of future biomedical devices designed to assuage nerve pain and treat neurological diseases.
Although ‘Dead Water’ may sound like the title of a movie that will make you steer clear from swimming in the ocean for a year, it is actually the name for an interesting fluid-dynamic phenomena experienced by nautical vessels (and, as it turns out, a detective novel by Ngaio Marsh). Right then…back on track.
Dead Water describes an effect wherein a vessel (i.e. a ship) that is moving by way of thrust produced below the water line (i.e. a propeller) begins to slow, sometimes even to a complete stall due to a mysterious force that seems to be dragging the vessel backwards. How does this happen? Well, there are things called internal waves; essentially, these are waves that appear much as the usual surface waves that you might think about when you picture ships at sea, but that exist below the surface at the interface of fluids existing at different densities. It is important to note, however, that an argument can easily be made to refer to internal waves as a type of mechanical (as opposed to electromagnetic or seismic) surface waves, as surface waves are waves that exist at an interface between differing media…just like internal waves, the usual distinction being that surface waves are generally referred to as those at an interface between a liquid and gas (i.e. the ocean’s surface and the air above the surface), while internal waves would be between a liquid and a liquid.
Stratified fluid interface in a kid’s science experiment. Photo Credit: fieldnotesfromfatherhood.com
You may recall doing an experiment growing up where you took water (dyed blue or red, etc.) and put it in a 2L bottle with some sort of cooking oil; because the two fluids were of different densities, they did not readily mix, but rather remained stratified. If you slowly rocked the bottle side to side (to avoid mixing the fluids), you created an internal wave! This is the kind of wave we are talking about right here, but rather than being produced by your hand moving a bottle, it is being produced by a ship’s propeller beneath the water.
In essence, the ship’s propeller is inserting energy into the fluid (the ocean), and this energy is being used to create an internal wave at the internal interface. As the ship continues to input energy into the fluid, the wave grows in amplitude, until eventually (much like waves at the beach), the wave breaks. When the wave breaks, it crashes against the boat; the reason you do not see direct contact between boat and wave in the above video is that the boundary layer between the boat’s hull and the far removed water is keeping them separated, but (rest assured) the energy of the breaking wave is transmitted through the boundary layer into the boat’s hull. This wave breaking creates local turbulence around the propeller, which further draws energy from the boat’s thrust (in addition to the thrust energy still being taken up by the waves forming down the line). The next part is a simple logical progression: if a boat uses a propeller to introduce energy into a fluid to produce thrust, then if an external force (i.e. internal waves) is taking up energy from the propeller, then it is also taking up energy from the production of thrust, then this translates to the boat not producing as much thrust as before and thus slowing down, perhaps even to a standstill (if the boat no longer has enough thrust to defeat the drag forces).
With the ship slowing down and possibly even stopping, even though its propeller(s) is(are) rotating at a constant speed, it is understandable how nautical travellers might have coined the term ‘Dead Water’ for something that they likely first perceived as being due to some crazy, mysterious sea monster that wouldn’t let them go, making them dead in the water…get it?
One last word on this topic…why is there these fluid interfaces in the ocean to begin with? Well, this stratification in ocean waters is caused by many factors, but mainly the difference in temperature, salinity (salt content), and thus density. For this reason, nautical goers are more likely to encounter Dead Water in regions with large salt inlets or largely varying water temperatures, such as near sources of inland fresh-water runoff into the ocean, or near glaciers.
Yours truly pictured on the right! Photo Credit: ThePolyPost.com
With only a couple of oral presentations and other tasks left to do, our project is nearing its end (don’t worry, posts will continue on another website but more on that at a later date!!!). My time as a technical writer so far has been educational, inspiring, and fulfilling. Not many people know this, but before I considered a career in mechanical engineering, I was laying the foundation to be a journalist. I was heavily involved in my middle school and high school newspaper programs and even earned an award for my work. You can even find me in at least three Cal Poly Pomona Poly Post issues!
Albert Einstein quote. Photo Credit: fossdoc.files.wordpress.com
When Team UV decided to create a website where we could inspire interest in the areas of Science, Technology, Engineering, and Mathematics (STEM) I couldn’t help but feel that same passion. Writing for a STEM related blog takes planning and plenty of consideration for various demographics that may visit our site. We have to balance the use of heavy scientific and technical jargon with the ease of describing complex scientific and technical topics. Shifting to one side or the other could easily “cut out” a group of readers if we are not careful. Take the presentations on flow characteristics or materials for example, our team could easily approach the topics in a text book fashion but those without the prerequisite knowledge of physics and engineering will become lost. If we approach it too simply, we dilute the experience of understanding exciting scientific phenomena and may even belittle the many years of work gone into such topics.
NCUR banner. Photo Credit: cur.org
The greatest moment of my technical blogging experience is when we met a TeamUV.org visitor at the National Conference on Undergraduate Research this past April in Washington. I still remember the look on his face when we brought up our website during the presentation and the excitement in his voice when he approached us afterwards. Meeting just that one person made the whole experience of driving over 3,000 miles and through blinding dust storms worth it.
I will continue to find opportunities to blog long after this project is over and I was surprised to find many exciting career paths in technical writing. It only makes sense that scientific websites and magazines have engineers on staff to write about various technical fields. Who else would make a better candidate to write a machine’s user manual?
Please continue to share our website and look out for a post about its future soon!
Until next time…
Eruption of the Calbuco volcano in Chile, April 22nd, 2015. Photo Credit: explosion.com
On Wednesday April 22nd, 2015 the Calbuco volcano in southern Chile erupted for the first time in 40 years, triggering the evacuation of 4,000 people in a 20km (~12.43mi) radius while disrupting air traffic over Chile, Argentina, and Uruguay. The eruption went on for an hour and a half and resulted in a plume of volcanic ash reaching 10km (~6.21mi) upwards.
At Team UV, our best wishes go out to those affected by this disaster and we are going to use today’s post to explore the science behind volcanic eruptions, in the hope of promoting a deeper understanding among our readers as to why and how these eruptions occur.
First off, we will be skipping over the science regarding the initial formation of volcanoes (plate tectonics, subduction, convection cells, etc.) in order to facilitate a more concise post/article; we will purely be looking at the eruption itself. So where do we begin? The answer is deep within the Earth’s mantle, far below the surface of the volcano.
Basic volcano. Photo Credit: science-at-home.org
The magma that exists deep in the upper mantle is under an enormous amount of pressure, and this pressure keeps the gases contained within the magma [i.e. water vapor (steam), carbon dioxide, sulfur dioxide, hydrogen sulfide, hydrogen chloride, and some additional strong acids] completely dissolved within the magma, meaning the gas molecules are distributed throughout the magma and are essentially embedded within the magma, much like the CO2 bubbles that are dissolved in your soda, that give it its carbonation, and which you do not see until after you have opened your soda, relieving the pressure within the container. Why is this the case that these gases are dissolved within the magma? Because the vapor pressure of the gases (the pressure exerted by molecules that escape from a liquid to form a separate vapor phase above the liquid surface; think of this as the pressure at which the molecules boil or evaporate out of the liquid) is lower than the surrounding confining pressure (the pressure exerted on the gases by the surrounding magma and rock, which is highly pressurized).
Okay, so we have now discussed the starting point, but what happens next? The next thing to occur will be a disruption in the balance between confining and vapor pressure. As the magma rises, it decreases in depth from the surface of the volcano, which means that it has less and less material stacked on top of it, which translates to a decrease in the confining pressure (the same way water hydrostatic pressure decreases with decreasing depth in the ocean). As the confining pressure decreases, eventually the confining pressure will drop below the vapor pressure, allowing the dissolved gases to begin to exsolve (emerge out from their dissolved state within the magma) and nucleate/form gas bubbles, or vesciles within the magma (just like when you relieve the pressure in your soda by opening the container, at which point the CO2 bubbles emerge). As this gas forms and expands, it effectively decreases the density of the gas-magma mixture, because for the same amount of weight as before, the gas-magma mixture takes up more volume than the magma-dissolved gas mixture of before, and density is defined as mass divided by volume. Since this new magma-gas mixture has a lower density than the magma-dissolved gas mixture, it floats (so to speak) to the top, allowing the bubbles to grow more and more as the magma rises further and experiences lower and lower confining pressures. In this way, the hot magma-gas mixture begins to rise faster and faster, accelerating as it moves upward.
Side Note: It is important to at least note that there are many causes for the magma to begin to rise in the first place (i.e. convection currents, insertion of new magma to pressurize the chamber further, etc.) and many considerations such as the increase in vapor pressure due to gas-content enrichment with crystallization of cooling magma, that we are not discussing here as they are not vital understanding the key fundamentals in a concise manner.
Gas bubble nucleation and growth as it rises to lower confining pressures. Photo Credit: bubblesbigidea.wordpress.com
When the magma, which is moving quite quickly now, reaches the surface cap of the volcano, it can break on through if the cap is not strong enough. This cap strength is, in part, a reason why volcanoes do not erupt repeatedly day after day (in most cases), as once a volcano erupts, the magma becomes lava, which can solidify the cap once again, potentially trapping the magma and gases for another few decades until the cap has been worn away it and the volcano is ready to burst again. Having said this, a high cap strength can also produce a much more violent eruption, as the amount and pressure of the gases contained in the volcano will be much higher prior to eruption if they have been held back by a strong cap, without any side vents.
So, assuming the cap breaks, and the magma and its gases burst forth and produce lava, and ash (mostly frozen bits of gas and lava due to the transition from inner-volcano temperatures and pressures to the much lower atmospheric temperature and pressure), what decides the type of eruption? This comes down to viscosity. Now, you have probably heard the word viscosity before; this describes the resistance to shear strain/deformation in a material (usually liquid) resulting from an applied shear stress. Viscosity is often described as (although, somewhat improperly) as the molecular thickness of a fluid/plasma; so syrup is highly viscous, while water is much less viscous. The viscosity of the magma is largely determined by the percentage of silica in the mixture, and this viscosity has a direct effect on the type of eruption.
A high percentage of silica translates to a high viscosity for the magma; if the magma is very viscous, it is harder for the gases to escape out from the magma. In this case, when the volcano does erupt, the gases explode out of the magma with violent force, blowing bits of ash, rock and jets of lava into the air.
Explosive eruption due to a highly viscous magma mixture. Photo Credit: Wikipedia.org
If the magma contains less silica and is more basaltic (containing more basaltic crust, which is essentially that found in the Earth’s crust beneath the ocean, which has a lower silica content), the lava will ooze out, as the gases are not strongly trapped in the magma. This is to say, the gases may freely exit from the magma, which is one reason why these eruptions tend to be much less violent, tend to ooze rather than burst, and tend to bubble more.
A bubbly, oozing basaltic volcano eruption in Hawaii. Photo Credit: followgreenliving.com
Side Note: In case you weren’t sure, the distinction between magma and lava is just essentially that lava is magma that is now external to the volcano.
So now that we’ve discussed volcanic eruptions, let us just take a quick second to figure out what’s going on with all the lightning shown in the first photo of this post; this lightning is termed volcanic lightning. There are multiple theories as to why this occurs, but almost all of them accept the following: as material is ejected out of the volcano, it breaks apart, either due to the explosive power of the eruption or due to collisions, as the material breaks into pieces, it is thought that differences in the aerodynamics of the positively charged vs. the negatively charged particles causes the two, differently charged particles to separate from each other. At this point, mother nature does what she usually does when there is a region of negatively charged particles separated from a region of positively charged particles: she bridges the gap by normalizing the charge imbalance with an electrostatic discharge…lightning. This seems to add another dimension of stunningly intimidating violence to the already destructive eruption.
Volcanic lighting. Photo Credit: Martin Rietze (nationalgeographic.com)
Hopefully this post has helped to build the foundation for a deeper intellectual understanding of the process of a volcanic eruption. It is unfortunate that these eruptions tend to devastate regions all to often. The understanding of these powerful volcanoes is the domain of oceanography; and to this end, oceanologists, geologists, and volcanologists are constantly working to deepen their understandings of these acts of nature in order to improve forecasting and possibly prediction techniques.
3D Bioprinter printing a Kidney. Photo Credit: on3dprinting.com
3D Printing is coming up in the news and research more and more these days. But that just goes to show the versatility of this additive manufacturing technique. The majority of manufacturing up to this point has focused on taking a block of material and removing the parts of it that do not belong, like Michelangelo sculpting the David. New techniques based on adding material have opened a new venue for the creation of products and allowed engineers and scientists to create designs that would have previously been limited by old manufacturing techniques.
One of the cool new applications of the 3D printer idea is for organ creation. Scientists at Princeton University and John Hopkins University have created a 3D printer that can print a human ear. The device first creates a scaffold, something for cells to grow on and maintain shape, out of hydro gel, then it adds cells that will grow and form cartilage that will be the final structure of the ear. Read more about it here.
Tricep dips using a chair. Photo Credit: plyometric-cardio-circuit.com
You’re running late. And now the hour you set aside to workout at the gym is reduced to thirty minutes. The drive to the gym takes about fifteen minutes so simply getting there and back will eat up the entire time budget. You figure you don’t want to skip out on a good workout so you decide that a home workout will have to suffice. Luckily you are a mechanical engineer so you have a few ways to maximize your home workout results.
Chest press with a 5 gallon water jug. Photo Credit: Youtube.com: eHow Sports
Chair. Photo Credit: infobarrel.com
Jumping squats. Photo Credit: popsugar.com
With these considerations, you’ll be sure to have a good quick workout. Get ready to turn some heads today.
Cynthia Lam’s H2prO device. Photo Credit: InterestingEngineering.com
This girl is definitely going places. Inventions to help improve the quality of life in a renewable and sustainable approach has been the main efforts of many scientists and engineers today. A participant in Google’s Science Fair, Cynthia Lam, developed a system known as H2prO that purifies water while simultaneously generating energy. In the images above; the upper portion is used for purification of water, while the bottom part is used for hydrogen generation which is connected to a fuel cell and the base unit for filtration of water.
Cynthia’s device uses titanium to separate the pollutants from the water. With the addition of oxidizing substances (methanol, glycerol, and EDTA) this mixture increases the production of hydrogen, which is used as fuel and to make the decomposition more efficient. Tests show that the H2prO has a 90% efficiency in the removal of organic pollutants, and the entire process can happen in only two hours. Unfortunately, the system is still unstable (even with such a satisfactory production of photocatalyic hydrogen) so data regarding energy production is slim to none. However, Cynthia is not giving up yet and plans to finalize her design to help many people in developing countries!
Photo Credit: factrange.com
I used to love wearing contacts. The first time I put them on was like seeing the world in full HD! The only problem is that I have very dry eyes which makes wearing contacts for extended amounts of time very difficult. Scientists at Oculeve have set out to solve this medical problem that affects more than 20 million Americans. The only catch? The very small device jolts you right in the lacrimal!
Tear Generating Device. Photo Credit: ExtremeTech.com
The implantable neurostimulator is injected or placed via a small incision below the eyebrow or in the nasal cavity. From here, the device sends small electrical pulses to the lacrimal glands to stimulate tear production. This process is controlled by remote and can generate tears as the user needs them. A major design challenge is in the recharging of the device’s battery. Getting to the device to charge every so often is impossible for obvious reasons so a form of inductive charging has to be used. This still leaves the user with placing a charger very near their face to charge the small battery; less painful but very awkward.
Do I see myself using this technology? Not for a very long time! For now, I’ll stay away from zapping my tear glands and use trusty eye drops instead.
More information about tears and the device here.
Until next time…
Typing. Photo Credit: wikipdeia.org
People spend a lot a their day typing whether it be on a keyboard, smartphone, or a card reader. Researchers at MIT noticed the value of this daily habit, and are putting it to a secondary use; they’ve developed software that can gauge the speed at which a typist is tapping the keyboard to help diagnose Parkinson’s disease. In order to type a word, your brain has to send signals down through your spinal cord to the nerves that operate your fingers. If your central nervous system is functioning perfectly, then you should be able to tap most of the keys at a fairly constant rate. But a number of conditions might slow the signal from the brain to the fingers, such as sleep deprivation (which slows all motor skills) and diseases that affect the central nervous system, including Parkinson’s.
For the first version of this study, the researchers were looking at typing patterns that indicated whether a person was sleep-deprived or well rested. They created a browser plug-in that detected the timing at which the volunteers hit the keys and found that the people who were sleepy had a much wider variation in their typing speed. They found similar results in their preliminary test with Parkinson’s patients; the 21 typists with Parkinson’s tapped the keys at much more variable rates than the 15 healthy volunteers. The researchers called it a “window into the brain”.
Right now, the algorithm they’ve developed is not refined enough to distinguish Parkinson’s patients from people who are sleep deprived, though the results might be clearer after a number of trials. The researchers plan to conduct a study with a larger group of subjects, but they hope that this type test could eventually lead to earlier diagnoses of Parkinson’s. Today most people are diagnosed after they have had symptoms for 5-10 years and to distinguish Parkinson’s from other conditions that might affect a person’s motor skills, like rheumatoid arthritis. They are currently developing a smartphone app that can test participants even more easily.
Big Sur Freeway 1. Photo Credit: tpl.org
After presenting Dory (Team UV’s senior project) to our adviser and a few interested technicians, I found relaxation in the beautiful landscapes of the Central Coast. During the trip, my girlfriend and I made a visit to Monterey Bay Aquarium on Cannery Row. To our surprise, we found a lesson in science and engineering in the most unsuspecting place…the Sea Otter Exhibit!
Cute otter picture. Photo Credit: imgur.com
The incredibly cute creature above is quite the wet weasel! Belonging to the weasel family, sea otters live along the coasts of the northern Pacific Ocean. Aside from being adorable and cuddly they have a few survival traits that make them scientifically interesting. Sea otter fur is one of the most dense around with up to a million hairs per square inch. They need this much fur because they have no blubber! Living in freezing water is made doable by this dense fur which is fluffed from hours of daily cleaning. Fluffy fur traps air between the otters skin and the freezing Pacific water, where it acts as a thermal insulator.
Layers of air can act as a great insulator, reducing the amount of thermal energy lost to the environment. We see this “phenomenon” practically everywhere; birds “fluff” up their feathers and people wear layers of clothing to trap air close to their skin.
Thermal energy flows from heated region to cool region; conduction example. Photo Credit: misswise.weebly.com
Thermal energy flows in one direction: from a warmer body to a colder body. Insulation such as air is used to reduce the rate of heat transfer in that direction. Many popular building materials use trapped air pockets to slow convective heat transfer (heat transfer due to fluid motion, which is caused by density changes in the heated fluid for the case of natural convection) while also reducing conductive heat transfer (heat transfer through a body due to physical contact). These materials are placed between walls or along pipes to control thermal energy flow. Another popular application is in double pane windows where an air space acts as a thermal insulator between the inside and outside environments.
Dual pane example. Photo Credit: customtemperedglass.com
It’s cool to see the science behind nature especially when you can see its application in other forms. Who knew I would continue to learn even while on vacation!
Until next time…
Graphic merging WWII-era Rosie the Riveter with the gender-underrepresented STEM fields of today. Photo Credit: researchmatters.asu.edu
Today’s post will be a bit accelerated due to time constraints imposed by a long To Do List for Team UV in the coming weeks as we prepare for more testing, analysis, conference, and possible journal submissions, but I thought it would be a little fun to talk about role models in engineering today. First off, a major issue is that there really aren’t many widely publicized role models in the world of engineering, which actually stems from a fact relating to the average academic process.
Growing up, we all take classes in fields such as English (or a comparable language class if you are in a country where English is not the primary language), Mathematics, Art, History, Biology, Chemistry, Government/Politics, and (maybe) Physics, but the only people who truly take engineering classes are people who are going to become engineers. This, unfortunately, creates a huge disconnect between the engineering world and that of the general public; the public knows what a historian does, what a businessman, artist, or chemist does, or at least has a fundamental understanding of what they do, but the only ones who truly know what an engineer does, are usually the engineers themselves. This directly translates to the lack of publicity of engineering role models, in that it is not very often that a movie, or TV show, or children’s book (for example) is produced that focuses on an engineer as a role model; if there is an engineer in the story, the role of the engineer is usually vastly misunderstood and often misinterpreted. No one is truly to blame for this, it is simply a consequence of the fact that only engineers truly take engineering course work (after all, should the general public be forced to struggle through extremely difficult engineering courses if they are not interested in engineering?). So how can we remedy this?
The best way is to help form a stronger connection between the general public and the world of engineering and, generally speaking, the most effective way to do this is by trying to inform the public about engineering at a younger age. What is the perfect vehicle for this kind of education? The use of role models through TV personalities, story book heroes, and even public speakers. Below I will quickly introduce you to a few engineers who have been working very hard to introduce a younger audience to engineering in the hope of inspiring the next generation of engineers.
Bill Nye the Science Guy. Photo Credit: fox43.com
Bill Nye “the Science Guy” is actually a mechanical engineer; bet you didn’t know that! Nye received his B.S. in Mechanical Engineering from Cornell University in 1977 and has gone on to receive many honorary degrees including a Doctor of Science honorary degree from Rensselaer Polytechnic Institute, an honorary doctorate from Johns Hopkins University, an honorary Doctor of Science degree from Willamette University, and an honorary Doctor of Pedgogy degree from Lehigh University. Nye is of course known for his educational television program “Bill Nye, the Science Guy” which spanned 5 seasons and 100 episodes (from 1993-1998) and taught a young audience about highly complex subjects such as heat transfer (for example) in simple and fun ways, often using experiments that could be performed by kids at home with their parents. Bill Nye helped to influence an entire generation of future scientists and engineers; one can only wonder how much greater the impact could have been if the show shined the light on Nye’s role as an engineer. None-the-less, Nye’s work has had a major impact and helped to show that science can be fun. If you are unfamiliar with the show, I highly recommend you seek it out and am sure you can find old clips on YouTube. Most recently, Nye was working on an interactive video game that would utilize lightweight wings that could be strapped to the arms and moved and flapped around to teach kids about the aerodynamics of flight.
Debbie Sterling. Photo Credit: infiniteexplorers.com
Debbie Sterling is a name you may not know, but she is an outstanding role model never-the-less. Sterling holds a degree in Mechanical Engineering/Product Design from Stanford University and upon graduating, did exactly what engineers are taught to do: she identified a problem and came up with a solution. Sterling decided to pinpoint the issue of gender under-representation in engineering, pointing out that only 14% of engineers worldwide are female. I can personally attest to the truth of this fact as, over my 5.5 year undergraduate career, I was made all too aware of the lack of gender diversity in my classes. This issue is magnified in mechanical engineering, which in my experience shows far lower numbers of females than other fields of engineering do. In my average mechanical engineering class throughout my undergraduate career, there were likely on average 1-2 females out of a class of 30-35 students on average; some classes had as many as 4 females, while many did not have any at all. In order to remedy this issue, Sterling has created a line of toys specifically targeted towards girls at younger age levels that aim to inspire interest in engineering. She essentially has made the female equivalent of the builder sets and simple machine toys that many boys enjoyed growing up, but that many girls were kept isolated from. Sterling’s company GoldieBlox is making great strides and I highly recommend that you check out their website.
Elon Musk. Photo Credit: iknowtoday.com
Elon Musk is the last person that I will list. Some of you may not know who Musk is, while others of you might be the type to follow his every move. Musk earned two B.S. degrees, one in Physics from the University of Pennsylvania and one in Economics from the Wharton School. Following these two degrees, Musk began his Ph.D. in Applied Physics (which is often very similar regarding coursework to both electrical and mechanical engineering), but left the program two days later to start his career as an entrepreneur, going on to start some very successful companies, namely: Zip2 (a web software company that was bought up by Compaq in 1999), X.com (an online financial services company that later became PayPal after a merger with Confinity), SpaceX (short for Space eXploration), Tesla Motors (an electric car company), Solar City (which Musk came up with the concept of, with his cousins actually starting the company, which is now the 2nd largest solar power system provider in the U.S.), and is currently setting up Hyperloop (which would provide a 350 mph+ form of ground transportation between Los Angeles and San Francisco). Musk is on this list for a different reason, while he has worked as an engineer, he is on this list more for the companies that he created. All of these companies are revolutionary by nature and thus the companies inspire interest among many future engineers, while Musk helps to get the word out through public appearances and his role as the face of these companies.
There you have it, three engineering role models of today. Engineering is such an amazing field and there are many people out there who could have made limitless contributions to the STEM (Science, Technology, Engineering, and Mathematics) fields if they were only educated about engineering as a possible career option at a younger age. Having said this, it is never too late, if we continue to take positive steps today such as establishing elementary school science/engineering clubs and programs or more widely publicizing engineering role models (such as Debbie Sterling, for example), we can help to produce the finest generation of engineers the world has ever seen tomorrow. It is said that you can do anything that you put your mind to…I wholeheartedly believe this, but in order to put your mind to it in the first place, you must know that “it” exists.
Top: Helmholtz resonance over a bottle (Photo Credit: Youtube.com; Nick Moore/Nik282K)
Bottom: Automotive airflow diagram (Photo Credit: hitechcae.com)
Most people have probably had the experience of driving in a car on the freeway and rolling down their window only to end up with an awful buffeting sound that hurts their ears. People familiar with this phenomenon often refer to it as “side window buffeting”; but in fact, this phenomena is actually caused by something known as Helmholtz Resonance. With that, let’s jump right into it!
As air flows over your car, it decreases the pressure in the flow due to what’s known as Bernoulli’s Principle; that is, in the absence of energy input and losses (which we will assume to be zero for this simple exercise in thought), if the flow is assumed to be incompressible (valid for the relatively low car speed), inviscid (negligible friction, as follows from our assumption of no losses), and steady (not changing with time), then if we assume that the change in elevation is negligible (perfectly valid for air, which is not very dense, over the 5 feet or so from the top to the bottom of your car), we can ascertain that if the velocity of a streamline increases, the pressure decreases, and vice versa.
Inverse relationship between velocity and pressure; flow acceleration and deceleration due to flow area change. Photo Credit: wwk.in
Now, let’s roll down a window while we are travelling on the freeway at elevated speeds. Remember, since we are moving, the pressure of the flow is lower than that of the ambient air far removed from the vehicle (outside the boundary layer); however, the air inside our car is essentially atmospheric pressure (i.e. the standard pressure of the atmosphere, no lower, no higher, just like the ambient air far removed from the vehicle), or perhaps even a little bit higher than atmospheric due to the pressurization from your air conditioning. So now we have the window open with a low pressure flow outside the car and a higher pressure inside the car.
The higher pressure air inside the car wants to go to the lower pressure region, so it is pulled out of the car. Now, we might expect that once enough air flows out to equalize the pressure, the flow will normalize and stop pulling from the car, but this is not the case; the air flowing out of the car has both mass and velocity, the two implicit components of momentum. Thus the air flowing out of the car has momentum and overshoots the equalization pressure, essentially giving away too much pressure from the inside of the car and thus leaving the car’s contents at a lower pressure now than the flow outside the car (creating an effective vacuum). Now the flow outside wants to move inside, but this flow has momentum as well and so it overshoots the equalization pressure and leaves the inside of the car over-pressured. As you might expect, this process can continue, with the flow moving back in forth across the window opening, getting larger and larger, until eventually the damping characteristics of the air itself keep the amplitude of this oscillation from increasing further, thus leading to a steady state oscillation of sorts.
Oscillation amplitude increase due to resonance. Photo Credit: AfifTabsh.com
This oscillation or flow buffeting is exactly what you are hearing, because as the flow buffets, it produces moving pressure waves with it, which our ears pick up as sound. Not only can this buffeting sound be very irritating, but it can also be damaging to your ear drums (which are in effect membranes that effectively convert vibration from pressure waves into sound); this can be especially true if you happen to be driving at the speed that maximizes the system resonance (which results in this Helmholtz Resonance). To better understand this, imagine pushing someone on a swing, if you push them and let go, they oscillate about the vertical swing position until the action of gravity, drag, and frictional losses brings the swing to rest. Now if you give them another push while they are moving backwards towards you, they will continue to swing, but not as fast or high as they could have because you pushed them before they got to the top of the arc. This time, you wait for them to get to the top of the arc (as far back towards you as they travel), and just as they have switch directions (and start swinging forward), you give them a big push. This time, you have added to the energy without cutting short their motion; if you continue to do this, they will swing higher and faster each time. Back to the car, if you are moving with the right speed, the air flowing into or out of the car from the next (upstream) batch of air can synchronize with the pressure osciallation already in place, leading to an increase in the oscillation amplitude (increasing the effective strength of the flow buffeting pressure); this is what happens when the buffeting gets really loud, to the point that it hurts your ears. Moreover, the pressure buffeting in and out of the window disrupts the airflow around the car, leading to vortex shedding, as can be seen in the video linked to here). So what can you do to stop this?
Well, you could slow down in order to avoid the resonance, or speed up for that matter (but not only could you reach another, higher resonant point, but you could also get a speeding ticket, which is no good). You could also roll down your window more or roll it up less (a larger opening will provide a deeper/lower pitch sound and a smaller opening will provide a higher pitch sound) or roll down other windows to relieve the pressure in the car [interestingly, rolling down the opposite, diagonal window usually provides more relief due to the direction of the airflow (rearwards due to the car’s motion and across due to the motion of the buffeting) , i.e. the back right window if the front left one is already down]. Another interesting option is that some cars (like the Chevy Volt) now come with so-called “window air deflectors” that re-route the air further from the window without messing up the car aerodynamics too much, as they deflect the air at an angle that allows it to rejoin the car immediately after the windows.
Chevy Volt window air deflector (lower right corner of the picture). Photo Credit: thecarconnection.com
It should be noted, however, that “side window buffeting” is not the only place that you can see Helmholtz resonance; this can also be seen in the old bar trick of making noise by blowing over a bottle (as pictured at the beginning of the post), many musical instruments, in some automotive exhaust systems that aim to change the sound of the exhaust, and even in some silencing applications in which the created noise is used to cancel out unwanted noise through destructive interference (this can be seen in some aircraft engines, automotive mufflers, and even weapon suppressors/silencers, wherein chambers are used just like the cavity inside the car to produce the noise cancelling pressure waves). Lastly, it’s also worth noting that this whole Helmholtz Resonance effect is more apparent on newer cars than old ones mainly due to the fact that newer cars are more streamlined, which is great for reducing drag, but brings the airlow closer to the car, thus inspiring this phenomenon to occur more easily.
Constructive and destructive interference. Photo Credit: animals.howstuffworks.com
Well, I hope everyone learned something today; now you can go tell your friends about the science behind that annoying thumping! Be sure to check back for Ben’s Open Mind post on Sunday and, I almost forgot, sorry for the 1 hour post delay, I am out of town and do not have readily available Wifi.
Liquid metal motor in action. Photo Credit: Gizmodo.com
A recent article published in Nature describes experiments that involve a special alloy of metal that is liquid at close to room temperatures. This alloy interacts with a surrounding fluid, usually water allowing it to propel itself. It is a huge feat, motion before has come from some form of external manipulations of magnetic fields, as in electric motors, or forced changes in pressure, as in hydraulics. This self moving metal can create motion on a much smaller scale leading to even smaller devices. Imagine a small camera that can zip through your bloodstream and sweep up any bad cholesterol lying around or guide a surgeon’s knife in a life saving procedure.
Read more here: http://gizmodo.com/this-liquid-metal-motor-moves-under-its-own-power-1690736185
The Journal of Nature is one of the largest scientific journals in the world, many groundbreaking advances in science are published through it. While subscribing to the journal itself is not cost effective for most individuals they do offer an RSS feed that provides brief summaries of the articles published in their recent issues. Check it out here: http://www.nature.com/nature/newsfeeds.html
Dory and Sheila-D in the top row and post-presentation team congratulatory pizza and beer at the Cal Poly Pomona brewery (Innovation Brew Works) in the bottom photo.
Photo Credit: Andrew Blancarte
First off, we want to apologize for missing our Thursday post, it has been a very hectic week for Team UV with almost all of the members going without sleep for 30 hours and above at some point or another; for example, I personally received about 8 hours of sleep total between Sunday morning and Thursday evening and at one point had to go about 30 hours without eating in order to get everything accomplished, but alas!, it was for a good cause and now Team UV can finally relax! (well, relax relative to other people, haha)
This past week and a half Team UV has had a week straight of building, testing, and programming for our vehicle, final exams, grad school visits, reports and projects due, graduation stuff, and of course completing our senior project! On Thursday, we delivered our final project presentation to the Mechanical Engineering board responsible for assigning our grades (we all received A’s), turned in our 140 page project report, and did a live demonstration of our vehicle Dory (Dynamic Observational Reconnaissance through biomimcrY). Dory (our Phase III vehicle) can be seen in the picture above, next to our Phase I propulsion system demonstrator Sheila-D (Submerged Hydrodynamically propelled Explorer, Implementation: Los Angeles – Deomonstrator)! (Read more about Sheila on our About page)
So this marks the “official” end of our senior project; however, this does not mark the end of the project altogether. We still have a lot of work to do regarding improving the build, adding more features, completing more advanced testing, and overall producing a more polished solution. Additionally, we will be attending the National Conference on Undergraduate Research (NCUR) at Eastern Washington University from April 16th-18th, the California State University system-wide Student Research Conference (CSU SRC) from May 1st-2nd (we are attending this because we won our session and award money at the Cal Poly Pomona Student Research Conference on March 6th), the Cal Poly Pomona (CPP) Senior Project Symposium at the end of May, and hopefully the CPP Symposium Showcase at that same time (this highlights the top project team from each engineering department).
Additionally, we will be looking to submit to some journals, quite possibly looking into at least one patent. Lastly, this website will continue publishing posts until the project ends, at which point these types of posts will continue on EngineeringAFuture.com. Anyways, thank you all for your continued support and I would like to remind everyone that we still have our fundraising campaign (GoFundMe.com/TeamUV), which will continue as long as the project is running as we still have quite a few costs ahead of us!
Please check back in tomorrow for a Well Read post from Ben!
Team UV reached the first dry powered milestone (rotating propulsor) tonight! Albeit backwards…haha
Check out the video above and we’ll be sure to post more videos as we make more progress in our testing!
Bigelow Expandable Activity Module. Photo Credit: smugsmug.com
The newest addition to the International Space Station (ISS) could be launching as early as September 2015! Bigelow Expandable Activity Module (BEAM) is a combined effort of Bigelow Aerospace with NASA and SpaceX and it is exactly what it sounds like, an expandable space habitat that will find residence at the ISS for the next two years. In those two years, astronauts will be inspecting and gathering performance data to see if it really is a viable habitat that can resist the rigors of orbit including radiation, loads from accelerations, and even micrometeorites. When it is not being inspected, it will possibly serve as a lounge area for astronauts or as an additional laboratory and that’s really the beauty of it. It can be anything you want it to be, it’s more space in space! The keyword in its description is “expandable” as astronauts will activate a pressurization system and expand the BEAM to roughly the size of a 10×12 foot bedroom using air stored within the packed module. What is so inspiring about the launch of the BEAM is that it could one day replace the ISS altogether. The inflatable segments can be connected together to make larger and larger habitats. If it’s performance is promising, it could mean a future where space hotels on the moon are possible or even full-fledged factories in orbit! There is just so much more room for activities! It’s making my head spin…
Photo Credit: thirdyearabroad.com
The world we live in today is driven by how much energy we have. For example when oil prices are high, we drive less and complain about all the things wrong with oil supply. When oil prices are low, we drive more and tend to forget about the core problem. The problem is not that there isn’t enough oil in the world or where it comes from, it’s how we go about energy production. There is no doubt that energy produced from coal and oil is “dirty” but it does have it’s perks. Traditional means of energy production (petroleum and coal) have been in use for a while now so the infrastructure is already there and its technology is well known. Petroleum and coal resources are abundantly found and the power produced from these plants is highly reliable. The same can’t be said for most forms of renewable energy. Renewable energy resources like solar and wind power, although very clean for the environment, have a few major hurdles to overcome if they are ever to be mainstream. A VERY long post can be made about how energy production, both on a national scale and a global scale, can be changed to better the environment and strengthen global ties but that’s not my plan. I simply want to share the pros and cons of each renewable resource and share why they aren’t currently taking the place of traditional energy production methods.
Renewable energy is diffuse, meaning low energy content per unit area and time. This is mainly due to the resources being in variable supply. You may be thinking: How is renewable energy variable? Well, take sunlight for example. The sun rises and sets in a full day. Energy from the sun can only be used when it’s out and most efficiently, when the suns rays are collected perpendicular to the surface of the solar panel. When the sun light fades out for the day, that’s it! Makes sense since solar collectors only work when there’s sun light to collect. At night, the solar plant no longer has its resource available unlike the coal or oil plant across town which can continue to generate power long after the sun sets. Now, a solar plant can store thermal energy from the sun’s rays but it can be unpractical or too costly to do so. Let’s take a closer look at individual renewable resources and the pros and cons associated with each one.
Solar Energy
Simple Solar Grid. Photo Credit: solarpowernotes.com
Pros:
– Large resource (any incident light that passes through the Earths atmosphere can be used for energy production!)
– Minimal pollution (sunlight can be used directly for electricity or as a thermal resource)
-Free! (Power plants don’t have to “BUY” sunlight)
Cons:
– Diffuse
– Cyclical (Can cause fluctuating thermal stresses in components)
– Not dependable (Sun goes down = no more resource)
– Design for high temperatures (Sun collectors need to handle the high temps of the solar irradiance)
– Storage (Electricity can be stored in batteries or heat can be stored in salt thermal pools)
– Concentrated Thermal Pollution (Higher temperature levels concentrated in a single area)
– Land use (collectors and receiver efficiencies range from 40-70% so many are needed to make the plant worth it)
Hydroelectric Power
Typical Hydro Plant Layout. Photo Credit: amailahydropower.com
Pros:
– Long Lasting (As long as there’s rain and moving water the plant can generate power)
– Low temperatures (No thermal cycles needed as it uses the energy of falling water to spin a turbine/generator)
– High efficiency (Converts work (falling water) to work (rotating turbine) which is the most efficient conversion possible)
– Cheap! (All it takes is a dam, a powerhouse (with a turbine and generator), and pipes!)
– Reliable (Water can be stored behind a dam for long running times even through droughts)
Cons:
– Habitat loss (Animals can be forced out of their homes to build a site)
– Nutrient loss (Nutrients needed downstream for plants and animals can be blocked upstream by the dam)
Wind Power
Wind Power Plant Layout. Photo Credit: yokogawa.com
Pros:
– Free! (No resource cost)
– Low operating cost (No thermal cycles; similar work to work conversion found in Hydropower)
– Huge resource (Wind is generated by a number of mechanisms making it abundant everywhere)
Cons:
– High capital cost (Huge Turbines = Huge Cost; machinery is large and over designed pushing cost high)
– Visual pollution (Usually located by mountains and deserts, wind power plants can take away from nature’s beauty)
– Noise pollution (Each passing blade produces a buffeting noise that make living near one hard)
– Bird Kills (Birds often times don’t see the blades of wind turbines)
– Land usage (Like solar energy, a lot of land is needed to make the plant worth it)
Biomass
Biomass Resources. Photo Credit: energy.ca.gov
Pros:
– Large Supply (literally anything can be used: plants, animals, wood, sugar cane, kelp, menure, sewage, waste, etc)
– Efficient use of byproducts (Nutrient rich byproducts are left over from this process which can be re-fed to starting point)
– Low pollution (low levels of carbon dioxide gas)
– Cheap supply cost (example: the old grease from the fast food place down the street can be used)
Cons:
– Soil depletion and erosion (Compostables once used for fertilizing are now used for energy production)
– Competes with food/feed growing (Land and resources are split between food and products used in energy production)
– Bulky (Transportation of waste and resources must be considered)
There is certainly enough renewable resources out there with many of them being able to provide for the worlds energy needs on their own. The problem, as I hope I showed here, is that many design issues must be tackled before moving away from traditional fuels. There is no overnight solution and there won’t be one for little while. Some of the cleaner processes pollute less than oil but physically harm the earth they sit on. Others are just too theoretically perfect to be implemented in real life. If you want my full view on how we can tackle this energy production problem let me know…I wrote a paper!
Please continue to share our GoFundMe site and give if you can!
Until next time…
F/A-18F Super Hornet at high angle of attack over a snowy mountain range. Photo Credit: navy-pictures.blogspot.com
Let’s start off with a scenario: You’re flying a sortie for the Navy in a reconnaissance-configured F/A-18F Super Hornet to fly in high over some mountain range in Afghanistan, take some pictures, and come home. You’re flying at 40,000 ft in order to both stay clear of the immensely tall mountain ranges and to remain undetectable and stay out of reach of small arms fire. Unfortunately, at 40,000 ft in this region, icing conditions are very common. Due to the low temperatures in this region (and especially at this elevation) combined with the all-too-often rainy or snowy conditions, you end up having to fly through falling snow or rain (which would be either already ice due to the low temperatures, or supercooled, meaning that the water drops are far below the freezing point, but have not frozen yet due to the absence of a nucleation site – which is essentially a solid surface on which the water can freeze…i.e. dust, other particulate matter, or the wing of an aircraft).
As you begin to fly into the poor weather, the water droplets begin to freeze on impact with the wing, building up a layer of ice on the wing of your aircraft. This ice quickly changes the surface roughness of your aircraft wings, changing the aerodynamics and lowering the speed or angle of attack that you can travel at without stalling (flow separation that leads to loss of lift). Furthermore, say due to the angle of incidence between your flight path and the direction the water droplets are coming from, the ice is forming more heavily on one side/wing of your aircraft than the other (and probably unevenly on each side). You start to feel the aircraft wobbling around in flight and find it much more difficult to control your roll, pitch, and yaw. You are now having issues flying the aircraft at the required speed, are having to fly at a lower angle of attack, and are having trouble controlling the aircraft. You have a decision to make: continue to put yourself, your Radar Intercept Officer (RIO), and your $60,000,000 aircraft in danger or abort the mission. Unfortunately, this situation is not too uncommon when icing presents a real problem to pilots.
With the development of unmanned drones for reconnaissance missions, we are able to push the envelope a little more, but still are wary of putting a very expensive aircraft into poor weather conditions (for both financial losses and the possibility of having a high-tech aircraft downed in enemy territory). This problem also exists for civilian air travel, and in many cases, general aviation pilots are not certified for flight into known icing conditions due to the clear and present danger. So what do we do to reduce the threat posed by icing conditions?
Aircraft wing icing and an expandable rubber boot used to break up the ice. Photo Credit: cloudman23.files.wordpress.com
There are a few traditional ways of dealing with aircraft icing. One is shown above, in which a rubber “boot” is expanded in order to break up the ice on the leading edge of the aircraft; obviously, this is not an optimal solution, as it temporarily changes the profile of the wing, and also does not get rid of all of the ice. Other methods include bleeding hot engine exhaust air over the wing and using “weeping” wings that release antifreeze over the surface of the wing, to name a few. These methods are all quite complex, require a lot of power, can alter the airflow significantly, and may even present environmental dangers (as in the case of the weeping wing).
In order to fill this void of optimal solutions, a company called Batelle has employed its researchers to develop a solution that consists of a carbon nano-tube coating that can be included beneath the topcoat of the aircraft wing and then act as a resistance heater of sorts to warm the wing from inside the wing to prevent or get rid of ice on the wings. This solution employs advanced materials science concepts in order to introduce a more elegant, non-invasive means of dealing with aircraft icing. Furthermore, the coating is controlled through an “intelligent controller [that] monitors the heater performance and applies only the power levels required for the flight conditions”, making it less power-hungry and more adaptable to any given situation! These benefits are realized even further on military Unmanned Aerial Vehicles (UAVs) (their principal application), where large sensor (or other) payload power requirements and desired lightweight dictate that a smaller than ordinary amount of power can be dedicated to de-icing. This solution has the capability to revolutionize the way we go about preventing or dealing with aircraft icing; now only if they could further development this solution for use in the de-icing of pitot tubes (devices used to measure airspeed – to figure out how fast you are flying; pitot tubes are notorious for encountering problems in icing conditions, where a false airspeed reading can lead to disaster).
Read more at: Engineering.com
Stress concentration around a hole visualized using photoelastic methods, with strain gages attached to the surface to measure strain, which can be back-converted to find the state of stress. Photo Credit: alliance.seas.upenn.edu
Stress concentrations (commonly referred to as stress risers or raisers) are areas in a material that, owing to problematic geometry, lead to…well, greater stress concentration in portions of the material/part. These concentrations can be great headaches to engineers, as the localized concentration of the stress means the part experiences much higher stresses in said specific regions than the average stress in the material as a whole (or than the material would experience without the riser), which can lead to failure at much smaller loadings than originally thought. Well what in the world does that mean?
To better explain this, we will examine a very simple case: pure tension in a rectangular sample. Imagine that you take a rectangular bar and pull on it along it’s axis, as shown below. We will make some simplifying assumptions for the purpose of ease of demonstration; assume that when you pull on the sample, you pull on the entire end face equally; that is, you distribute the loading across the entire face equally. Also assume that the material is homogenous (the same physical & mechanical properties at all points throughout the material), isotropic (the same properties in all directions), and uniform in cross-section. These assumptions will hold for demonstration and are sometimes used in applications in which strength is not of major concern, but generally speaking, it will be very difficult to apply a load evenly across a surface (picture gripping a piece of metal with a pair of pliers…the grip point is the point of load application and does not cover the entire face, but rather is localized), materials will never be homogenous (due to voids, inclusions, and other manufacturing defects), many materials will not be isotropic (a piece of un-altered steel is isotropic, but wood, for example, has directional strength in the directions of its “grains”; many other materials also express different properties in different directions), and many geometries will betray the assumption of uniform cross section (as we will see shortly).
When we pull on the material, that force is transmitted through the material with an equal and opposite reaction internal to the material, as shown in the center image of the above picture. This force may be shown as a single resultant force vector (like in the center image), but is actually distributed over the entire inside of the material (as shown in the right/3rd image). When this load/force acts over this area (and remember, we are only looking at pure tension…the load is applied perfectly perpendicular to the material cross section, as otherwise we would induce bending), it creates a normal stress that is defined as the applied load divided by the cross-sectional area. Under the assumptions we made before, this should mean that every point in the material experiences the same normal stress, meaning that in order for the material to fail, the average normal stress in the material needs to exceed the failure strength (in this case, the applicable tensile strength).
But what happens when we apply a stress concentration, by introducing a discontinuity in the geometry (i.e. a crack, sharp edge/corner, or change in cross-sectional area)? The stress distribution can no longer be uniform, as the loading has to be re-routed to avoid the discontinuity as it travels through the material (for the case of geometric stress concentration), as shown for the simple case of a circular hole in the material below.
As can be seen, the distribution tends to bunch up around the hole, creating a higher concentration of stress. From a mathematical standpoint, the local normal stress in the region of the hole has also decreased as the cross-sectional area of the sample at the hole location is now less (imagine cutting the bar in half perpendicular to the loading and looking at it from the end…instead of being the full rectangular cross-section of before, there is material missing), thus the normal stress is higher because we are applying the same load, but now are dividing it by a smaller area than before. This means that if we apply a loading to the uniform sample that created a stress under the tensile strength of the material before, that materials would not fail, but now if we apply the same exact loading to this new sample with the stress riser, the sample could very well fail due to the heightened stress at the discontinuity. This should be seen as quite alarming as this means that parts can fail at lower loadings than expected, and while our example shows a huge hole in the part, it should be noted that small cracks, or simpler sharp corners and other minimal, yet abrupt changes in the geometry can affect the state of stress in a major way.
Effect of geometric discontinuities on stress distribution. Photo Credit: teachengineering.org
We should also note that highly concentrated stress regions can be formed by applying loads non-uniformly, as in the example of gripping material with pliers discussed in the 2nd paragraph, where we apply a load on a very localized, concentrated region (picture taking a 10 lb weight and placing it directly on a table vs. taking the same weight, balancing it on a thumbtack, and then placing it on the table with the tack point down). Just as before, we have decreased the effective are that the load is applied over, except this time, we reduced the area of the stress region by changing how the load was applied, whereas before we did it by changing how the load was transmitted.
Exaggerated demonstration of effect of concentrated loading on stress distribution. Photo Credit: mace.manchester.ac.uk
For this reason, engineers must be very careful when they design parts to include factors of safety to account for material imperfections, possibly use non-destructive inspection (NDI) techniques to examine critical parts for cracks in situations where a crack could prove catastrophic (for example a crack in the side wall of a submarine hull that could spread due to cyclic fatigue due to cycles of compression/de-compression when traversing great depths, surfacing, sinking again, surfacing again, etc.), and must avoid abrupt changes in geometry in the design of the part itself. Luckily, in this day and age, we understand much more about internal stresses and stress distribution thanks to new testings and stress visualization techniques, but the subject of stress concentrations is one that I cannot stress the importance of enough! (I apologize for the bad pun)
Effect of rounding sharp corners using “fillets” on stress concentration. Photo Credit: corrosionpedia.com
Additionally, this was purely looking at one-dimensional loading in an over-simplified material and geometry, but in the real world we can have parts of really intricate geometry, made from materials with unbelievable amounts of anisotropy (different properties in different directions), subjected to combined three-dimensional loading of tension, bending, torsion, shear, perhaps compression in a different region, with hygrothermal loading (loading due to both moisture and thermal effects), subjected to different kinds of corrosion, vibrational modes, impact loading, and the list just goes on and on! Anyways, hopefully today you learned a little bit more about one of the endless topics that engineering encompasses! I will leave you with some really cool photoelastic stress visualization pictures in which the refraction of light is a function of stress (due to birefringence), thus the material essentially shows different wavelengths (and thus different colors) due to differences in stress throughout the material, helping to visualize stress (and stress concentrations).
Stress concentration at a sharp corner in a plastic protractor (Photoelastic visualization). Photo Credit: Wikipedia.org
Photoelastic visualization of stress distribution in plastic eating utensils. Photo Credit: flickr.com/photos/chrisar/ (Christian Rein)
Photoelastic visualization of contact stresses on a marble in a C-clamp. Photo Credit: osa-opn.org
Photoelastic visualization of rolling contact stresses due to a cylinder rolling on a flat surface; the cylinder is rolling to the left. Photo Credit: Wikipedia.org
Stainless Steel I-Beams. Photo Credit: stainlessshapes.net
Steel is the foundation of the modern structure, be it buildings, airplanes, or ships. Plain carbon steel is a simple mixture of carbon and iron in just the right proportion to provide excellent strength. As humans have taken to the sky lighter materials have been required. This has led to dominance of aluminum, titanium, and composite materials for weight savings. These materials are stronger per unit weight than steel but more expensive and less plentiful. Scientists have just recently discovered a new steel alloy that provides the strength to weight ratio of titanium using much more available materials. This could lead to a revolution in the structural steel world, but for now they need to find a way to manufacture it outside of a lab setting. Read more here: http://www.gizmag.com/steel-alloy-strong-light-titanium/35996/
Plateau-Rayleigh Instability in a water sheet from a fountain. Photo Credit: f***yeahfluiddynamics.tumblr.com
Here at TeamUV.org, we have often discussed some of the finer intricacies of fluid mechanics (or usually more specifically, fluid dynamics, as opposed to fluid statics). Generally speaking, however, we have looked at fluid flow and behavior from a very macroscopic view, that is we have looked at fluids as they act on the macroscopic length scale, within which objects are practically visible by the naked eye. In the various fields of engineering, most engineers would only need a macroscopic understanding of fluid mechanics in order to perform rather rudimentary calculations and analysis. For example, if an engineer was asked to determine the hydrostatic pressure exerted on a submerged pressure vessel lying on the bottom of the ocean or if they were asked to size (determine pump impeller diameter, pump speed, power input necessary, pump type, capacity/flow rate, etc. for) a pump based off of the known pressure gradient (perhaps it has to force water through a very fine filter while maintaining a certain amount of pressure), elevation change, or required change in speed, a macroscopic view of fluid mechanics would often be sufficient. But is this always the case?
Of course not! The golden rule of engineering regarding what you need to know to perform your job is that there is no golden rule of engineering regarding what you need to know to perform your job. Engineering is a highly dynamic field, with ground-breaking discoveries made continuously…right now, somewhere in the world a scientist or engineer is making a major contribution to the future of STEM. Additionally, engineers (especially mechanical engineers, who have a very large, diverse knowledge base) can be asked to do anything at any given time, and they must be able to figure it out! So to say that the macro scale is the only one an engineer needs to be aware of (especially in the field of fluid mechanics) would be a gross understatement. So where does that leave us? Well now would be a good time to explain what is meant by “length scale” and to share some of the typical ones. After that, we will very briefly roll through some of the fluid effects that exist on smaller length scales, as these highly complex phenomena are beyond the scope of this post.
Orders of magnitude as they apply to the Eiffel Tower viewed from different length scales, demonstrating how different length scales reveal different details. Photo Credit: iupui.edu
A length scale is essentially a parameter for deciphering the characteristic length associated with a phenomena. For example, if we are talking about the atomic scale, we are generally talking about phenomena that occurs in the size range of atoms, on the order of magnitude of pico- to femto-meters (10^-12 or ^-15 m). If we are talking about the microscale, we are talking about things on the order of micrometers (10^-6 m) such as water droplets or the thickness of a human hair. The macroscale would be associated with cars, mountains, you and I, etc. and would be essentially anything in your field of vision, i.e. probably from millimeters on up to kilometers (although the macroscale is not precisely defined). From here, we would likely move on to the astronomic scale, which is generally used to refer to phenomena on the scale of the universe, or Megameters (10^6 or 1,000,000 m) on up. For example, if you were to move from an atomic to micro to macro to larger with regards to your hand, you could envision protons and neutrons in your skin cells and then zoom out to bacteria under a microscope and then zoom out further to your hand itself and then zoom out further to the Earth itself, further to the Milky Way Galaxy, and so on and so on. In fact, if you have a second, you should check out this zoomable tool for visualizing the scales of the universe.
So back to fluid dynamics after a very lengthy detour, why should we care about length scales smaller than the macroscale? Because turbulence (as well as all fluid motion and other physical phenomena in general), is a result of phenomena on smaller length scales. So in order to actually understand the onset of turbulence or how fluids react with each other or with structures, etc. within the framework of deeper understanding, we must understand the microscopic behavior of fluids. Much of this behavior is defined by fluid stability and instabilities, which are not only very interesting to look at, but are the building blocks for the entire field of fluid dynamics as we know it! At this point, I will quickly show some pictures of some of the more common instabilities, but will not go into descriptive detail as scientifically, mathematically, etc. they are extremely complex phenomena that many fluid dynamicists spend their entire careers studying.
Kelvin-Helmholtz Instability simulation. [Media Credit: Wikipedia.org]
Kelvin-Helmholtz Instability made visible by clouds. Photo Credit: UP.edu
Rayleigh-Taylor Instability simulation. Photo Credit: Wikipedia.org
Rayleigh-Taylor Instability seen in dye drops in water. Photo Credit: Colorado.edu
Gortler Vortices on an oscillating cylinder within a flow marked by fluorescent dye. Photo Credit: APS.org
Cracked egg. Photo Credit: WashingtonPost.com
Boiled eggs are delicious, I’m pretty sure no one will object to that, but have you ever thought of unboiling eggs? A group of chemists out of UC Irvine and Australia have made this discovery which has the potential to change the biotechnology industry and dramatically reduce the time and cost for production of cancer treatments among other applications!
Now this wasn’t done simply for the sake of unboiling eggs, it was used to demonstrate how powerful this new technique of returning tangled proteins to their original form really is. Proteins are made of chains of amino acids that are folded and arranged in a specific way. Changes in pH and/or temperature disrupt the bonds holding the proteins in their original shape causing it to deform and tangle. So when you cook an egg you are actually tangling proteins which causes them to change from clear to white. The process is known as denaturation and is problematic for scientists who are trying to recycle valuable proteins after use. Previous methods of solving this issue exist but they are time consuming and expensive. This new process, however, gives results in minutes.
Professor Colin Raston’s vortex fluid device. Photo Credit: WashingtonPost.com
In the findings published in ChemBioChem, egg-whites were first boiled for 20 minutes at 90 degrees Celsius (194 deg. F) (plenty of time to tangle the delicious proteins). To revert a protein in the cooked eggs called lysozyme, urea was added to liquefy the solid whites. The resulting substance was then placed in a vortex fluid device which is a high powered machine designed by Professor Colin Raston’s laboratory at South Australia’s Flinders University. This machine applied shear stress to the proteins which encouraged them to untangle and re-fold to their original form.
There is huge potential for this discovery that can streamline protein manufacturing and make cancer treatments more affordable. Think about this next time you’re making omelets. For more information on the findings please visit http://onlinelibrary.wiley.com/doi/10.1002/cbic.201402427/abstract
Panasonic’s photocatalytic water purification system. Photo Credit: wonderfulengineering.com
Note: Our apologizes for the missed post on Tuesday; we had some technical difficulties and so have posted the original Tuesday post (this post) for today and will be posting the original Thursday post tomorrow (Friday 1000 hours) instead. Regular scheduling will resume on Sunday.
In some parts of the world clean drinking water is quite rare as the water sources are polluted and purification methods are not available. Panasonic is developing a new technology to address this problem. This technology uses the sunlight for purification of the water extracted from the ground. Recently, a system was presented by the company that uses photocatalysts and sunlight to purify water at a high reaction speed. This readily improves access to clean water, in areas where needed.
The recent breakthrough that led to the discovery of this technology is the system’s ability to bind titanium dioxide (TiO2), a photocatalyst capable to react under ultraviolet light. TiO2 comes in super fine particles and is hard to collect once it has dispersed in the water. Previously, other larger materials were used to bind the TiO2 to them, but it was a loss of active site surface area. The way this technology by Panasonic differs from those found before, is the discovery of Zeolite particles’ (a commercial adsorbent and catalyst) ability to bind the TiO2 particles. This solves the problem by enabling photocatalysts to maintain their active site. As the two particles are bound together by electrostatic force, there is no need for the binder chemicals. As the new photocatalytic particles are stirred, the Zeolite releases the TiO2, which then disperses throughout the water. The resultant reaction speed is much faster as compared to other methods and the processing of large amounts of water is supported. The TiO2 binds to the Zeolite again if the water is still left, which makes it easy to separate and recover the photocatalysts from the water for later use.
The main idea of this project is to develop a small-scale version of this purification system, which may then be deployed at different places where purification of water is needed. See how the system works below!
Panasonic’s photocatalytic water purification system process diagram. Photo Credit: wonderfulengineering.com
Prompt: Mechanical engineering is inherently ambiguous to those without an intimate knowledge of its principles. As mechanical engineering students, there is an excellent chance that most of the people you know believe that your job consists of working on cars, acting in the role of a technician, or some related role. Even people from many other engineering disciplines rarely know exactly what we study or what we do. None of these people are to blame; rather, this is simply a consequence of the fact that the only people who take (many) actual mechanical engineering classes are mechanical engineers (/mechanical engineering students). When a person grows up and moves along through the educational system, they take classes in History, Mathematics, Literature, Biology, Chemistry, Art, etc., and perhaps even Physics, but they never take any sort of engineering class unless that is the career path they choose to follow. As a result, many people who could have possibly unearthed a deep love for engineering never received the chance to do so. In recent years, many K-12 schools have been moving to fix this and have been especially working to expose traditionally-underrepresented student groups to the world of engineering at an early age. Come up with either 3 ideas (or one idea from 3 perspectives) to help spread awareness with regards to the existence of the world of engineering (more specifically, mechanical engineering) to people at a younger age, thus hypothesizing as to how we can help more possible future (mechanical) engineers discover their ambitions.
“Ownbot” a robot created by engineering students from Victoria University of Wellington (New Zealand). Photo Credit: victoria.ac.nz
It’s true. When I say that I’m studying mechanical engineering, people think I work on cars or I’m learning to work on cars. Even after explaining what I actually learn in my classes, most people stop listening after about ten seconds and conclude that just I’m a “fancy” mechanic. Not the case. When I was as freshman in high school I had no idea what engineering was. All I heard was that it involved a lot of math and it was not for everyone. I agree with both statements but the latter I think overstated. How can you decide something is not right for you if you don’t even know what it is? This is why I’ve come up with three ways to spread awareness of the world of engineering.
1) Teach team oriented problem solving, systematic reasoning, and creative problem solving at a young age.
I feel too many kids do not know how to work together effectively or know how to logically solve a problem they’ve never faced before. I was with my thirteen year old cousin recently and asked him to set up a music stand for me while I got everything else ready. There were three pieces to the stand and after 30 seconds of trying he said it was broken. It clearly wasn’t. Now I’m not saying he’s “dumb” but he had no idea how to logically figure out how to solve this problem. He just simply tried one thing, it didn’t work, and decided it was must be broken. That is not the kind of world I want to live in which is why these kinds of things should be taught much earlier. Even if you have no idea how to solve something, there are creative, logical, and scientific steps you can take to better understand what is going on. MIT has developed programs like Scratch to teach these ideas to kids through basic programming. http://scratch.mit.edu/
2) Presentations
Now I’m not saying a thorough and extensive lecture on PID control to 5th graders, but a very well polished presentation on how cool engineering can be. I think people have to be exposed to a more visual representation of what an engineer actually does instead of rumors and hear-say. I’m sure 10 year old Abe would have been incredibly impressed and inspired if he saw an underwater vehicle designed and created by students at the local university. How all these engineering principles came together into something that he could touch and see move around a pool so swiftly and majestically. A really good presentation can make the word “engineer” seem not so scary for an entire generation.
3) Engineering Competitions
I think recently more schools have gotten into engineering competitions. There’s high school solar boat, elementary school robot programming, and even model bridge building competitions. These are incredibly fun because most of these projects are in collaboration with engineering programs at universities so young minds can really get into the engineering mindset through a mentor. I did solar boat and it was one of the most fulfilling things I did at Warren High. If I wasn’t a part of it then and there I probably wouldn’t have chosen mechanical engineering as my major so I definitely encourage more of these types of competitions.
Overall there has been a bigger push to teach kids how to do things they could never do before. Building, problem solving, and working together. They are all a big part of engineering but of life also. In today’s 21st century I don’t think you can progress without these skills so I’m glad that I learned them in the classroom. Hopefully in the coming years more people will realize how important and interesting the field of engineering really is.
First and foremost I apologize for the overall lateness of the content of this post, as I originally intended to publish this post in my previous round of posts, but due to time constraints decided to publish a post on a snake-proof full-body suit (equally interesting!) and invest a little more time into making this post a little easier to understand before publishing…hopefully it worked out, haha. So as I noted a while back (while discussing the future of undersea warfare), with growing challenges in the undersea and technological domains, innovation is becoming more and more important within the realm of defense engineering (as well as all other fields of engineering). One promising direction engineers are looking to in all fields of engineering is towards the application of advanced biomimetics (a.k.a. biomimicry) in their designs. Why might engineers and scientists want to study how we can mimic fish, or other animals or nature in general? Because nature truly is the ultimate engineer. Animals have been optimized to perform the tasks that they need to and to do so efficiently and thus have been nearly perfected for their environments and their lifestyles.
Considering the facts just presented, it becomes a little more evident why undersea warfare (as well as other undersea activities and applications) may benefit from the implementation of biomimcry. Take the Shortfin Mako Shark for example; this is the fastest species of shark in the world and it utilizes its large caudal fin (as will be defined later), slim, streamlined, torpedo-like body, and its stronger, faster-acting muscles (as enabled by its endothermic abilities, through which it generates additional heat through its unique metabolism, keeping the muscles warm and agile, thus defining the Mako as a “warm-bodied shark”) to reach cruise speeds of 25 mph and burst speeds up to 50 mph and leap 30 ft high! Another example of the awe-inspiring abilities of marine creatures and how scientists and engineers have attempted to mimic them is that of the color- and texture-changing abilities of the octopus, as Andrew talked about a while back.
Shortfin Mako Shark. Photo Credit: Sam Cahir via dmarron.com
To better understand more specifically how engineers can utilize biomimicry in order to advance undersea vehicle technology, we will now discuss how exactly fish swim. Fish generate forward motion, or swim, through what is termed locomotion. Locomotion is simply a fancy word for describing movement from one location to another; animal locomotion may take many forms and can be seen in all types of environments, whether terrestial (on land), aerial (through the air), or aquatic (through the water). There is a myriad of other qualifiers that can be used to further divide up the different kinds of locomotion (if you are interested, you can learn more about animal locomotion at this link), but we are going to solely focus on fish locomotion, that is, how fish get from one place to another.
Fish locomotion can be divided up into two main modes of motion: Body-Caudal Fin (BCF) and Median-Paired Fin (MPF). The BCF mode accounts for about 85% of fish families’ main mode of propulsion, whereas MPF makes up for about 15%. Now before diving into the swimming mechanisms associated with these two modes, we will make one more distinction: undulatory motion (also referred to as undulation) vs. oscillatory motion (also referred to as oscillation). Undulation is by far the most common type of motion (both within the BCF & MPF modes) and can be thought of as a lateral wavelike movement; picture a fish seemingly weaving its way through the water or a rope with waves travelling down its length…this is in essence what undulation manifests itself as: undulation in fish movement appears as lateral waves travelling down the length of the fish’s body. In short, undulation is lateral wave motion along the length of the body, relative to the body, as if the body was stationary but experiencing waves along its length. In contrast, oscillation focuses more on the body being essentially rigid and moving the tail side to side…picture your dog wagging its tail, or a pendulum oscillating about the line connecting the pivot point to the base. Now that we’ve got that covered, we can move on to quickly listing the common types of fish motion and listing a few examples!
Eel anguilliform lateral undulation. Media Credit: lyle.smu.edu
Time-lapse picture showing positions of a dog’s tail throughout its oscillation. Photo Credit: mediaorchard.com
Body-Caudal Fin (BCF)
This type of movement depends on the fish effectively wiggling its body in order to move its caudal fin sided to side, thus producing thrust which has components in the forward, backward, and transverse directions. The largest component of this thrust is that in the rearward direction, thus the movement of the caudal fin propels the fish through the water.
Undulatory:
1. Anguilliform: With this kind of motion the undulatory waves are passed throughout the entire length of the body (except perhaps the head); because the entire body is extremely flexible, both forward and backward motion are possible. The most typical application in which you would see this kind of motion would be in eel locomotion.
2. Subcarangiform: This motion is similar to anguilliform, but the forward 1/3-1/2 of the fish does not move, while the rest of the body still generates transverse undulations. It is now significantly harder for the fish to swim backwards as it is not longer symmetric front to back and the forward portion of the fish is much more stiff than the rear. Common examples of fish with this kind of motion would be most trout and salmon.
3. Carangiform: Also similar to anguilliform, but only the last 1/3 of the body acts to produce thrust and the caudal fin itself is usually more stiff to produce greater thrust with the reduced active length of the body. Fish that swim like this are usually fairly narrow transversely, likely to increase the surface area used for thrust generation by increasing the height to width ratio; these fish also tend to be stiffer overall and faster moving.
4. Thunniform: In this group, all undulation is restricted to the caudal fin/tail and the region connecting the main body to the caudal fin (called the peduncle); these types of fish usually have very large, stiff caudal fins, have been optimized for high speeds and long distance travel, and are capable of generating hydrodynamic lift in order to compensate for the fact that many of them are not neutrally buoyant and thus need to move (and in doing so, generate lift) in order to keep from sinking. Examples are most species of tuna and sharks.
Oscillatory:
1. Ostraciiform: These types utilize slow pendulum-like movement of large caudal fins and are similar to Thunniform, but operate much more slowly. As a result, this type of swimming is usually either simply an auxiliary, low-energy style of swimming used by some MPF fish or, if used by fish as their main style of propulsion, those fish would generally have internal countermeasures such as poisons since they are incapable of fleeing predators.
Various physical characteristics of a generic shark, nearly all of which appear on most fish.
Photo Credit: Wikipedia.org
Median-Paired Fin (MPF)
This type of movement depends on synchronization of various combinations of usage of the pectoral, dorsal, pelvic, and/or anal fins.
Undulatory:
1. Rajiform: Characterized by vertical undulations along large pectoral fins…think sting rays and manta rays for example.
2. Diodontiform: Characterized by undulations that travel along large pectoral fins…like a porcupine fish!
Porcupine fish with undulating pectoral fins; Diodontiform motion. Media Credit: Tumblr.com
3. Amiiform: Utilize long undulatory waves along large dorsal fins, such as a Seahorse.
4. Gymnotiform: Uses undulations of a long anal fin; much like the Amiiform, but using the anal fin on the underside of the fish rather than the dorsal fin on the top side of the fish. An example is the American Knifefish.
5. Balistiform: Anal and dorsal fins undulate; while rare, this can be seen in the Triggerfish.
Oscillatory:
1. Tetradontiform: Dorsal and anal fins oscillate either in phase (together) or opposite of each other; an example would be the Sunfish.
2. Labriform: Pectoral fins osciallate in a way in which they produce both lift and drag, which can be resolved into components, one of which would be rewards, thus producing thrust. In essence, the fish flaps and rows its pectoral fins, producing thrust. An example of a fish using this kind of motion would be the California Sheephead.
So there you have it, an organized view of the many sorts of propulsion mechanics associated with fish, each having its own advantages and disadvantages. By studying these kinds of characteristics of fish, scientists and engineers can come up with innovative solutions by looking to the sea for the answers for the one constant truth for scientists and engineers alike is that we never stop learning and so when you can’t find a sufficient answer in your textbooks and theories, you need to be able to conduct experiments and analyze the world around you in order to come up with new ideas.
This is exactly what engineers within the defense industry are doing currently as they conduct research and begin designs of new cutting-edge, innovative undersea vehicles that utilize biomimicry to provide for increased performance, better power efficiency, and increased stealth through the minimization of flow signature. While we here at Team UV are not utilizing biomimicry in the design of our propulsor (for which we use something else all together), we absolutely have biomimetic influence within our design and as can be seen in the picture at the top of this article, have looked to adapt a streamlined shape and fin-like control surfaces in addition to a number of other biomimetic schemes (i.e. stability, maneuvering, buoyancy control, drag reduction, etc.) to produce a truly innovative solution that is currently in the manufacturing/assembly stage. And so we again ask for your increased support through our fundraising campaign at GoFundMe.com/TeamUV as we near the end of our project in the coming months.
As promised, in another week or two, we will release some pictures of the current vehicle design/model.
2015 National Conference on Undergraduate Research. Photo Credit: CUR.org
A few days ago, Team UV was selected to present some of our research regarding our underwater vehicle and its propulsion system at the 2015 National Conference on Undergraduate Research, which will take place at the Eastern Washington University from April 16th-18th! Thank you to our readers for your support and for following our blog; we will not know what day, timeslot, or room we will be presenting on/during/in until early March.
Also, we want to thank those of you who have contributed to our fundraising campaign and mention that we have now raised $1,630 thanks to your generous donations! Thank you for your support and please continue to help spread the word as we continue in the purchasing and manufacturing stages!
We also want to note that no donation is too small and not a single penny donated will go to waste, it will all be used to increase the quality of our vehicle, to add capabilities (through additions to the sensor suite or additional drag-reducing technologies, etc.), and to enable us to conduct better testing (i.e. the construction of a flow tank for actual flow visualization). As an example of this, we are excited to inform you that through some of your donations we have been able to get our hands on a superhydrophobic substance (from Hydrobead) that will help us to decrease drag on the exterior of our vehicle significantly through the repulsion of the surrounding water. As follows from the above statements, any money that we raise above the $5,000 will be put directly into the project in one of many ways, including (but not limited to) those listed above.
Dyed water drops on wood coated with a super-hydrophobic substance. Photo Credit: TheFutureofThings.com
In addition to this, at this point, it is unclear as to where the funding to attend our research conference will come from (whether out of pocket or at least partially funded through our school’s research office), so all donations will help us significantly!
Lastly, I want to remind our readers that we will be trying to post funding progress updates as often as possible and that you can find a full-sized PDF of our pull-tag poster on our Sponsors & Donations page if you would like to print one out and post it to help get the word out. If you would like to help out in other ways, it would mean a lot to us if you would tell your friends/family/coworkers/etc. about our fundraising campaign (and possibly ask them to share it as well), share it on Facebook, or perhaps even just spread the word about TeamUV.org in general, as our biggest goal with regards to this website is to inspire interest in the fields of Science, Technology, Engineering, and Mathematics (STEM).
Any help is greatly appreciated and please come back Sunday for Andrew’s Open Mind post!
Oxygen-absorbent crystals before (left) and after (right) becoming saturated with oxygen. Photo Credit: TheHigherLearning.com
71% of the Earth’s surface is covered with water and, for the most part, it is unexplored by humans…until now! Scientists from the University of Southern Denmark in conjunction with the University of Sydney, Austrailia have discovered a crystalline material that is capable of absorbing oxygen from both air and water! This revolutionary material can bind and store oxygen in high concentrations then control the release time of that oxygen depending on what the user needs. The benefits to this are unquantifiable but could be especially beneficial to deep sea divers and to those suffering from respiratory ailments.
A study led by professor Christine McKenzie alongside Jonas Sundberg of the University of Southern Denmark involved about 10 liters of microscopic grains of the material and found them to be enough to suck the oxygen out of a room. Even just a few grains contain enough oxygen for a single breath and that material can even absorb and supply oxygen from water surrounding deep sea divers. The oxygen saturated material is so effective that it is comparable to 3 full pure oxygen tanks under pressure! One of the key ingredients is the metal cobalt in the material which controls the process of absorption which gives it the molecular and electrical structure to be capable of absorbing oxygen from air and water. Remarkably the absorption and releasing process can be done many times without losing the ability much like a sponge in water. The impact that this discovery will have on the medical field as well as exploration will be monumental and I look forward to it. For more information please visit: http://www.collective-evolution.com/2014/10/10/absorbing-crystal-can-steal-oxygen-from-air/
Christmas tree. Photo Credit: images.clipartpanda.com
While there are many stunning artificial Christmas trees on the market there is nothing that can beat a real Christmas tree. The species of tree for the festive holiday varies in different parts of the world, they all have roughly the same green foliage and smell. When it comes to getting a tree to decorate for the holidays you’re faced with one problem regardless of the species you go for in that the leaves or needles will turn brown and fall off. A group of schoolgirls in Australia have now come up with a simple solution to make the Christmas tree last longer in the home.
A year 7 class of girls from a school in Rose Bay, Sydney, Australia, looked into what made the foliage of the typical Christmas tree turn brown and shed the needles. They looked at the trees in different conditions. They placed branches into tap water, hot water, beer, energy drinks and a container that had water with the branch being sprayed with hairspray. They performed the experiment with 50 branches of Pinus Radiata, otherwise known as the Monterey Pine tree. They divided the branches into groups of 10 and checked the branches out carefully over a period of 27 days. They used an instrument to measure the leaves health by applying a pulse of light. This measured how efficiently the needles converted light energy to chemical energy.
Professor Moles said that she believed that the coating of the hairspray stopped the plant from being able to sense chemicals that came from the branches that were dying, which in turn would normally trigger more decay. This works in the same way as leaving a rotten apple in a bowl and it turning the whole bowl bad. Another theory was that the hair spray may have helped to keep moisture in. So it seems that if you want to get the best from your Christmas tree you should give the tree a spray with some hairspray. Of course, it would be advisable to do this before you decorated the tree.
This may be a tad bit late considering the timing. I know I will make sure to remember this next year!
Robotic arm. Photo Credit: http://www.gdc.larc.nasa.gov
The 2014 year has been a good one to us in terms of technology. Many of these devices have not been publicly displayed enough for people to take notice. So I’m here to fill you in! Here is your list of the top 10 greatest feats in engineering!
10. Form-fitting compression space suit to aid in planetary exploration
-Dr. Dava Newman, a professor of Aeronautics, Astronautics and Engineering Systems at MIT, created compression garments that incorporate small, springlike coils that contract in response to heat to improve upon the outdated, clunky spacesuits astronauts currently wear.
9. Simple, cheap, paper test for cancer
-Another research team at MIT has definitely achieved success in this department as they developed a simple, cheap, paper test that can diagnose cancer, in a similar fashion to a pregnancy test.
8. Pocket spectrometer is your personal molecular scanner
-This pocket friendly device uses near IR spectroscopy to identify the materials of the object it’s scanning. It works in partner with your smartphone via Bluetooth and the data from the scan is sent to the cloud to undergo algorithms, before feedback is sent back to the smartphone.
7. Daewoo’s exosteleton that gives its workers super strength
-Daewoo began testing exoskeletons that allow workers to pick up, maneuver and hold objects weighing 30kg with no effort – perfect for their shipbuilders. A backpack carries the power for a system of hydraulic joints and electric motors running up the outside of the legs.
6. We finally have something that can be called a working hoverboard
-An interesting use of electromagnetics and the hoverboard was a front for the new take on the technology which has potential for a lot of other great possibilities.
5. Ridiculous 43 Terabits/sec data transfer
-The High-Speed Optical Communications team at the Technical University of Denmark set a new record for data transmission this year, passing 43 terabits per second worth of data over a single optical fiber. To put this in perspective, Reddit user candiedbug points out: “At 43 terabits per second you could download Netflix’s entire 3.14 petabyte library in 9.7 minutes.”
4. Google Cardboard lets you experience virtual reality with stuff you already have
-With some android software you can create your own virtual reality experience with things possibly lying around your home right now. All you need is some cardboard, Velcro strips, magnets and plastic lenses (and of course an Android device), and you can experience a 3D virtual reality available from numerous apps.
3. Wireless electricity is now a thing
-Wireless electricity has been creeping into our lives with the likes of wireless charging smartphone docks where the handheld devices lay on top of a pad. Now, WiTricity have used resonant wireless power transfer technology to develop a commercially viable product that can charge your devices without the need of them being left on a pad. It also works through wood and metal.
2. SpaceX’s FALCON 9 reusable test vehicle reaches 1000m
-Elon Musk dreams to colonize Mars in the future but this year his company achieved a milestone with their reusable rocket, reaching 1000m. At a time when budgeting for space sciences is at risk, the industry needs more efficient and less costly solutions to continue our exploration beyond our own planet.
1. Solar power can be generated in the dark
-Researchers from MIT and Harvard have created a way for solar panels to absorb and store the energy from the sun’s radiation, which can then be used on demand to create heat.
However, do not forget that we landed on a comet! In my opinion that is the greatest engineering feat! Feel free to look into each one of these great engineering feats yourself!
Scanning Electron Micrograph (SEM) of the insect’s leg gears. Photo Credit: livescience.com
Nature is a great engineer. So many of the innovations that have propelled humankind through the ages can be found in nature. On average, a gear is one of the smallest components of almost anything that moves. These components handle everything from timing to power transfer. Humans have only been using these tools for maybe 1000 years. Scientists have discovered that nature has been using them for much much longer. The rear legs of a plant hopper are bound together using gears so that the legs spring at exactly the same time propelling the insect where it needs to go without requiring any more complicated thought. Pretty much all the great ideas can be found in nature and this is one of the reasons why biomimicry is becoming more and more popular. Read more about the discovery here
Movie explosion special effects. Photo Credit: screenjunkies.com
Prompt: Entertainment engineering brings to light some of the more light-hearted aspects of engineering. Entertainment in itself is one of America’s most popular pass times and encompasses subjects such as film, television, music, games, reading, comedy, theater, circuses, magic, street performance, parades, fireworks, animal shows, and the list just goes on and on. Entertainment holds a very special place in the world and always has; whether in the form of the plays of Ancient Greece, the jesters of the medieval times, the shooting exhibitions from the days of the wild west, the black & white films that the soldiers of early wars watched to forget about their harsh reality, or the 3D special effects that seem to captivate us all on the building-sized screens of today, entertainment has always been there to help relieve the stress of those who indulge in it. Today this is especially important for the citizens of this great country as we work longer hours, spend more time stressed, and find the well-appreciated release provided through entertainment to be more and more refreshing. For all these reasons and many more, the entertainment industry is here to stay and will constantly require great engineers to keep it afloat and help it to progress. Pick 3 forms of entertainment and describe how a mechanical engineer could contribute to them, or 1 form and 3 considerations.
One interesting subset of physics and engineering that is very often modeled in movies, but is vastly overlooked, is that of fluid mechanics. Although not usually noted, fluids (liquids, gases) are not the only things that can be described by fluid mechanics; fluid mechanics is often applied to study the movement of plasmas and the flow of granulated material (i.e. sand) for example. Perhaps more significantly, fluid mechanics finds vast application in the way of FSI (Fluid-Structure Interaction), which finds usage in all kinds of fields, such as the movement of bridges in high winds, aeroacoustics (such as was seen in my earlier post on owl stealth), and the effect of water hammer on piping materials to name just a few applications. An interesting phenomena that is frequently seen in movies, and that requires a lot of work in the way of application of fluid-structure interaction theory and computational physics, is the movement of fields of tall grass in the wind. This motion is actually quite comparable to the movement marine plants in tidal currents and thus is often analyzed similarly. To learn more about the movement of grass fields in the wind, head on over to FYFD.
Wind acting on a field of tall grass. Photo Credit: Tumblr.com
Additionally, if anyone has ever seen an action movie, chances are there was some shooting in it, and chances are if there was a lot of shooting in it, someone got shot. In some particularly gruesome movies, the bullet is shown to impact the skin and create the wound. The field of terminal ballistics (consisting of entry, internal, and exit ballistics) is highly complex and to model the bullet-target interaction correctly takes a vast knowledge of materials, fracture mechanics, and many other fields of physics and engineering.
Bullet-apple interaction from a study at MIT. Photo Credit: Flickr.com
Lastly, explosions have become a focal point of the majority of movies out there these days; their modeling requires a vast knowledge of combustion theory, flame-front propagation, fluid mechanics, heat transfer, and (once again) fluid-structure interaction.
Explosion modeling. Photo Credit: Tokyo-gas.co.jp
So just remember, next time you see a movie and think to yourself ‘How do they make it look so real?’ or ‘These special effects are incredible!’, you have the worlds of science, technology, engineering, and mathematics to thank for helping to create a realistic experience!
CFD study of airflow through a disc brake installed on a wheel/tire. Photo Credit: apps.exchange.autodesk.com
For much of our design we had to do some complicated analysis on the way the water acts around our vehicle. To do this we had to do some Computational Fluid Dynamics. The complex math involved in these calculations has been briefly touched on in past posts, but this post is here to tell you how we did it. Autodesk offers a massive suite of analysis software for free to students and one of them does the analysis we need: Autodesk Simulation CFD. There are many great tutorials out there on how to do this but here are the basics we used.
All of this analysis is right at your fingertips if you know where to look (and happen to be a student!) It’s pretty cool the things you can find out!