Robots tend to be either very rigid or very soft, but neither extreme is ideal; ideally, machines could both squish themselves into tight spaces and remain sturdy for strength-dependent tasks. They just might, thanks to a team-up between MIT and Google's Boston Dynamics. The two have developed a composite material that can switch between hard and soft states on the fly. The design mates a compressible foam inside with an external wax coating. If a robot needed to deform, all it would have to do is soften the right joints with a bit of heating. It could even heal damage by heating and cooling an affected area.