총 맞아도 잘 굴러가는 바퀴
Veritasium 한국어 - 베리타시움 · 23:25 · Watch on YouTube
NASA built an airless, puncture-proof tire from nitinol, a nickel-titanium "shape memory alloy". The metal can take very large bends and still spring back to its original shape, which ordinary metals can't do. The vid...