it's very neat but i wonder about the activation method: heat. it's not the easiest to work with. i'd assume you have to keep the muscles at a regulated temperature in order to get the contraction you expect, which i imagine would be some type of water cooling (like sous vide).
activation would also be tricky. first thing that comes to my mind is a resistive wire element, but i wouldn't expect it to last for many contractions without breaking.
The examples they suggested were all passive, like blinds that close when it gets too hot inside, and so didn't have to deal with those issues.
