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  • Hey, it's me Destin welcome back to Smarter Every Day.

  • Here's the deal

  • Um, I'm in a super weird place in life right. I've got four kids. I'm an engineer. I've got this YouTube thing

  • I give talks, but my channel name is Smarter Every Day

  • I've been wanting to go back and get a PhD for years, but it's never felt right.

  • It feels right now. I met a guy; his name is Dr. Kavan Hazeli. We click, we're on the same wavelength

  • I'm going to get a PhD and there's more to it than that.

  • Dr. Hazeli applied for a National Science Foundation grant. Over a five-year period, he's got a million bucks

  • And he's asked me if I'd come work with him as a part of my PhD I could help work with

  • transfer students for research, and the research is incredible. Like that's the thing about the University of Alabama in Huntsville, right?

  • This is a school located right next to Marshall Space Flight Center. You got all these army organizations nearby. There is a ton of

  • Research that happens at UAH so here's the deal. In this video

  • I'm going to show you three research programs that are actively looking for

  • undergraduate transfer students. Topic number one

  • 3D lattice structures printed by NASA. We're testing the strength. Check out. Dr. Hazeli's lab.

  • I'm about to film Dr.Hazeli when he doesn't expect it

  • Dr. Hazeli Hey

  • Okay, so so this is doctor Hazeli and he's in charge of the lab here

  • It's... what what do we call this? It's the

  • so what we do here basically, we are we are learning about material behavior, so we try to understand

  • how materials reacts with different environments could be impacts could be loading could be just cycling the materials and

  • The entire idea is learned from the material behavior and in for manufacturing

  • so Dr. Hazeli showed me this and he's like "are you interested in getting a PhD," and I said

  • Yes

  • Because what do you call this so we call them lattices structures. Basically we

  • remove the mass from materials by carefully printing them out so the idea behind them is make the matter as light yet strong

  • Enough to withstand a lot of pressure and lots of different environments

  • So we have this set of the topology which was given to us by NASA

  • Our ultimate goal is to optimize the topology

  • Which one is strongest?

  • For quasi-static compression test Octet Truss is the strongest one

  • What what about for impact, is it different?

  • We haven't tried here, so we wanted to do it today maybe

  • Is it possible that impact is different and quasi static

  • yes, possible why?

  • Because the mechanisms by which material deform at highest strain rate is different than quasi-static

  • Okay, Andrew is about to do this first shot and it's a dodecahedron, right?

  • Yes, right

  • Dodecahedron. So the way this works is there's this large piston over there?

  • He pressurizes the piston, slams it into this long rod

  • This rod is going to impact the sample right there

  • So you can get the input and output energy of this impact and you can see how much energy that particular sample absorbed

  • Three-two-one

  • Three-two-one

  • So it got squished

  • Is it like, perfectly flat?

  • Yes Let me see

  • Wait nuh-uh

  • And it's hot! It's hot?

  • Yeah, you cannot dissipate a lot of heat when deformation is very fast so that amount of pressure

  • stored in the material. This was very hot

  • So it's hot right now? Yeah Can I feel it? Oh, it sure is

  • It sure is so that was dodecahedron right What are you going to do next?

  • So the next is a rhombic dodecahedron

  • sweet? Let's do it. This is a big deal like everybody knows you can 3D print metals

  • But this problem is very difficult. For example stress equals force divided by area, but what is the cross-sectional area?

  • Do you treat it like a bolt material? Do you measure the cross-section of each individual leg on the topology?

  • What is the angle, how does it matter blah blah blah, there's a ton of stuff

  • We're measuring the overall strain of the material. We're acquitting that to a stress

  • This is the future of metal. Like we are figuring out how to work as humans with 3D printed

  • structures and is fantastic. So that's one option for research. Another one is Dr. Gabe Xu who's working at the plasma

  • Electrodynamic research lab. This is incredible stuff. Okay, so Dr. Xu is... just.. I mean I like walk in the room and

  • He's showing me an ion thruster. That's how it rolls here.

  • The planned use is eventually, we want to develop it for small satellites, Cube sets

  • 1U, maybe not 1U, say 3U or 9U Cube Sats

  • A lot of them have orbit maneuvering capabilities

  • So what kind of ISP, would you see from something like this? I mean I've played a little bit of Kerbal Space Program

  • [laughs] For very small ones like these, ISP, you may be looking at it. I'll say like a thousand seconds

  • Whoa

  • Those are startup transients Startup transients?

  • Are you not entertained?! I walk in and the man's firing an ion thruster

  • And he's like, "oh whatever, just startup transient. It's not a big deal." What?! What's hap-

  • Dr. Xu just made it work like MacGyver, only ion propulsion. Is that pretty much what happened?

  • like MacGyver? [scoff] MacGyver you know

  • oh come on just embrace it

  • [laughs] So there is a electromag.. electromagnet wrapped around

  • the thruster, which, without it turned on [...?...]

  • Generate a magnetic field inside to trap the electrons to reduce the electron currents of the anode basically

  • So we're trying to control the amount of current that the anode is seeing

  • really? So is, is thrust directly proportional with current?

  • thrust is propor... [waves hands] kind of

  • It's is proportional to the acceleration voltage, and how many ions come out which you can sort of say is current?

  • Aaand it just died [Laughs]

  • So to be clear dr. Xu is interested in getting research assistants at the undergrad level

  • Which would be what these students are doing here, so they can basically come work with you and develop ion propulsion

  • yeah, we've got different propulsion plasma projects

  • That's awesome

  • I know right? Is that awesome or what? Okay, the last lab. I've actually featured this on Smarter Every Day in the past

  • It's called the atom lab. They are researching

  • How butterfly wings work and they're doing it with these really

  • cool cameras that can calculate the position of a butterfly wing just by putting a reflector on his wing when he flies.

  • okay, I'm in the atom lab with Dr. Kang and you get to do some pretty cool stuff with butterflies, right?

  • mm hmm What do you do?

  • so we are interested in butterfly flights or in particular, the monarch butterflies

  • Because they are known for their migration distance, which is the longest among insects.

  • no one really understands how they are able to make that distance which can be as long as

  • 4,000 kilometers, so we are trying to understand their aerodynamic

  • mechanisms and to apply that to develop bio-inspired micro air vehicles

  • these cameras emit infrared rays which will reflect off of these markers and we can treat those markers

  • When we have a bunch of cameras, we can triangulate those markers to one position in space

  • You can study the motion or the kinematics of the butterfly and the way it flaps so this is the CFD

  • Simulation and here we are seeing the work the [?] activities that the wing is producing will interact

  • The fluid around it so is that is that a vortex that you're showing us? That is, that is a vortex. those are three-dimensional shapes of the vortex around the wing.

  • So you're modeling vortex shedding yes using computational fluid dynamics exactly and retro-reflective

  • imagery from actual yes biological specimens yes, yes, that's where we are going, towards that, yeah

  • And the whole point is to make a micro air vehicle or at least study the efficiency of

  • The butterfly so that we can understand how to apply that toward of micro air vehicle The possibility of actually using it to do, cool things

  • That's rad! This flapper is hooked up to a force transducer at the bottom and

  • this measures the force produced by the flapper and we can see the forces in our

  • software which is directly connected to the force transducer

  • [Mechanical flapping noises]

  • So lets do a... I don't know why that's so exciting but it

  • It reminds me of those birds. You remember the old birds that you could wind up and throw? yeah, and then they fly, yeah

  • You're trying to figure out by flapping

  • modes how a butterfly steers

  • I'm trying to get the communication between

  • The flapper and our transmitters She's trying to develop our remote controller so that she can

  • control something like this are you doing this? Yes This looks like electrical engineering

  • [laughs] A Little bit Really? So, that's awesome!

  • What year are you I'm a junior Really? Are you gonna be a grad student?

  • I am going to grad school, yes.

  • So the whole, the whole point of this whole program Dr. Hazeli is

  • Undergrads can come in and they can work with you on the matrix stuff the squishing

  • Structure, designing the light structure material, for impact situation And it's that's probably what I'm working on Exactly

  • Yeah, and so and then there's also the ion propulsion and plasma. That's true and also we have the project about

  • supersonic wind tunnel with the Prof. Ligrani

  • and you have already discussed about Dr. Xu now and also here in the atom lab

  • Students come to the program. They have opportunity to interact with the more senior students and also the professors or to get some hands-on experience

  • About the active research which is important for education and the government

  • This is a big deal, so if you want to check this out

  • You can go to -- you made a website, didn't you? We did.

  • matrix.uah.edu matrix.uah.edu yes that's right

  • you can check it out, work with me work with Dr. Hazeli, work with butterfly wings

  • big deal! I'm excited about this so go to the website matrix.uah.edu

  • and apply and and who is it for? It's for transfer students? for transfer students basically

  • They get to pay for their education through the NSF money we have, and in return

  • They need to improve their GPA and be involved with the research

  • So it's not for free. You actually have to work hard and do a good job

  • Well, they don't have to but if they need to stay in the program... [laughs] so yeah you gotta work harder

  • So is that what you're thinking, Dr. Kang? Yeah, okay, cool anyway matrix.uah.edu. That's an NSF grant

  • That doctor Hazeli is leading up, and I'm working on so go check it out. Thanks

  • bye

Hey, it's me Destin welcome back to Smarter Every Day.

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觸摸等離子體--每天更聰明 193 (Touching Plasma - Smarter Every Day 193)

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    林宜悉 發佈於 2021 年 01 月 14 日
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