Shape-shifting microrobots could be used for bone repair

Just add electricity, and these newly engineered biomolecules harden and heal.

curved dark strip with a plain black side and wiry grey side
A bone inspired microrobotic material. The black material is a polymer called polypyrrole, which changes its volume based on voltage. The other side is alginate gel, which is combined with biolmolecules that harden like a bone in the right solutions. Credit: Olov Planthaber/LiU