A SYNTHETIC starfish is flipping somersaults in a fish tank in a Japanese lab. The bizarre creature represents the first steps on the road to new types of artificial muscles for robots and prosthetic limbs.
The five-limbed minibeast is a simple lump of gel cut from a sheet of a polymer called PAMPS. It is the brainchild of Mihoko Otake and her colleagues at the universities of Tokyo and Hokkaido.
PAMPS is an “electroactive” material: in other words, it deforms when placed in an electric field. This happens because charged groups of atoms strung along its long, bendy molecular backbone are attracted to an external charge, forcing them to huddle together.…
