Energy absorption in a bamboo foam

We discuss the ability of soap films to absorb the energy of an impacting projectile. If the impact velocity is large enough, solid objects or water drops pass through the films without breaking them. However, during each impact a small part of the original kinetic energy is extracted, which is revealed by considering collections of parallel films (so-called bamboo foams). Then, the impacting object is observed to stop after crossing numerous films. The total energy absorbed by the foam is found to be the total energy of distortion of the films, integrated over the multiple crossings. The case of inclined films is also considered, and found to affect the trajectory of the projectile.