A material called vanadium dioxide is used to produce the robot muscle. When it is heated to 67 degrees Celsius, the compound changes from an insulator to a conductive metal, yielding a huge amount of strength during the transition.

This lets the robot muscle throws objects 50 times heavier than itself over a distance five times its length, all within 60 milliseconds — faster than the blink of an eye.

Heating of the robot muscle can be done either with a tiny heating pad or with an electrical current. The heating process can also be triggered optically since heat is generated when vanadium dioxide absorbs light.

Physicist Junqiao Wu, the leader of this search project, said: "With its combination of power and multi-functionality, our micro-muscle shows great potential for applications that require a high level of functionality integration in a small space."