How NASA Reinvented The Wheel

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A huge thanks to everyone at NASA Glenn Research Center for having us at the SLOPE Lab, showing their work on this indestructible tire, and helping with the science and animation.
A huge thanks to everyone at Smart Tire Co for showing us around their facility, teaching us about nitinol, and letting us flatten their tires.

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References:

Buehler, W. J., Gilfrich, J. V., & Wiley, R. C. (1963). Effect of low‐temperature phase changes on the mechanical properties of alloys near composition TiNi. Journal of applied physics, 34(5), 1475-1477.

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Special thanks to our Patreon supporters:
Emil Abu Milad, Tj Steyn, meg noah, Bernard McGee, KeyWestr, Amadeo Bee, TTST, Balkrishna Heroor, John H. Austin, Jr., john kiehl, Anton Ragin, Benedikt Heinen, Diffbot, Gnare, Dave Kircher, Burt Humburg, Blake Byers, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Josh Hibschman, Mac Malkawi, Juan Benet, Ubiquity Ventures, Richard Sundvall, Lee Redden, Stephen Wilcox, Marinus Kuivenhoven, Michael Krugman, Cy ‘kkm’ K’Nelson, Sam Lutfi.

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Written by Derek Muller, Katie Barnshaw, & Emily Zhang
Edited by Trenton Oliver
Animated by Mike Radjabov & Ivy Tello
Coordinated by Emily Zhang
Filmed by Derek Muller, Emily Zhang & Raquel Nuno
Additional video/photos supplied by Getty Images & Pond5
Music from Epidemic Sound
Produced by Derek Muller, Petr Lebedev, & Emily Zhang
Thumbnail by Ignat Berbeci

[Fozzdaddy]

As an engineer I’ve known of nitinol for a while, did some labs with it in college. But I never saw the example of bending the nitinol pipe in half and have it return to shape. Awesome material

[speedfastman]

Can you do "how NASA reinvented cat girls" next?

[valkyrie]

They use this metal in orthodontia too. The wires for braces are made out of this. They are “programmed” as the parabolic shape that the orthodontist wants, then bent and tied into the braces. The heat of the mouth (aka your body heat) makes the wire “want” to return to its original shape, thereby pulling your teeth into the proper position! I was amazed when my orthodontist showed me this, it was super cool to see as a kid.

[jakeperrine]

My father was on the design team for the Apollo rover (and LEM, etc.) and received an award for his team’s design of the rover tires. It’s so cool to see this generations upgrades to the concepts they used back then!

[sv]

I love that these 2 engineers are so happy with their work, they look genuinely happy.

[astigstudio]

Veritasium videos are the type that don't need any fancy high pace over energetic editing needed. I will watch the video all through out no matter what

[RTR]

one of my customers was one of the engineers that was hired to study Nitinol in the late 60’s and 70’s he’s still inventing today and is currently close to a breakthrough in magnetics

[MiguelHernandez-ndpr]

Hands down one of the best videos you've made and one of the best on YouTube. So helpful. We watched this video as a family this morning with teenagers and 8 year old. They thought this was amazing. Great job inspiring science in the lives of my children.

[GillyTech]

I discovered a congenital defect in my heart at age 34. It was a penny sized hole in the two top chambers called the atria. They used a nitinol device to close the hole and allow heart lining cells to grow into it. This stuff saved me!

[Eyerleth]

I had NiTiNOL wires in my orthodontics as a teenager. They worked to slowly, continually push the teeth into their new positions, rather than needing painful tightening every couple of weeks. Quite an impressive material!

[matijakruhoberec]

These types of videos is what keeps me going through mechanical engineering school. Seeing things I learned about being applied in real world situations, but also reedeming the knowledge I gained and thought was useless during materials courses.

[iLLadelph]

21:34 shots like this really communicate science fantastically. "put your full body weight on it" you can see Derek physically interacting with the thing and playing with it like any student might

[jnmharris]

I did a report on nitinol in 8th grade science...41 years ago...nice to see this video explain its properties even further. Cool!!

[kedo]

I love the excitement and positive energy from all those engineers! They’re really happy to show their work.

[ml]

Wow, what a cool video and comprehensive demonstration and explanation of nitinol and its applications! Great job on this one, probably one of my favorite Veritasium videos. And thanks to everyone at Glenn and the contractors that work on this awesome tech and explained it so thoroughly!

[adrianrahardjo]

In the first 10 minutes, they basically covered several key topics of a Materials Science degree in a very interesting and memorable way. I really wished this video was available a few years ago when I was still in uni...

[ExtremeBirdTypography]

The plane with the vortex generators was the coolest part to me. Seeing them flip up and down due to the heat was awesome.

[kob]

Fantastic. Been curious about Nitinol for over half a century and this is the best bit on it I've seen yet. Thanks

[ivanmartindelcampo]

I vividly remember in my gen chem lab class at uni we had an experiment where we messed around with Nitinol and I was completely in shock and awe with how it was behaving. I want to say that day was the moment I fell in love with material science and now love learning and researching about polymers as a chemist!

[paulpease]

The stress-strain curve reminded me of my PhD work on single DNA molecules. We could grab the two ends of a single DNA molecule (with laser beams, of course), and make force-extension curves. DNA also goes through a phase transition under physical strain. At first it acts like a low stretch string, where the force increases quickly as the extension gets close to the full length of the molecule. At around 65 piconewtons (65x10^-12 N) it will “overstretch” and at a relatively constant force (hallmark of a phase transition) will stretch to ~1.7 times its normal length. When the force is reduced it will go back to its original length, although there can be significant hysteresis depending on how quickly the load is reduced. The overstretching is coupled to an unwinding of the double helix, so in effect it’s a wind up toy and can be used to apply torque, e.g. rotate a microscopic bead. DNA is a super cool material, I hope Veritasium does a video on this stuff.