Artificial muscle that curls
when warmed

Artificial muscles are of interest in both industrial (robotic) and medical (prosthetic) technology.  On that subject, MIT engineers have developed a binary material that resembles the way a thermostat works.  When heated, the materials different thermal-expansion rates causes the fiber to coil.  “Specifically, MIT researchers used a very stretchable cyclic copolymer elastomer and a much stiffer thermoplastic polyethylene as their materials. They bonded them together to produce a fiber that–when stretched out to several times its original length–naturally formed a tight coil. . . .”  Further, they realized that they could program the heating and cooling process to produce a specific force.  MORE

Image Credit:  Felice Frankel, MIT News