Compliant electrodes are attached to each side of the membrane and cause it to stretch when voltage is applied. A membrane switches from its more compact state to its stretched state when voltage is applied to its electrodes. (©Alejandro Posada)

Researchers at the Max Planck Institute for Intelligent Systems in Stuttgart developed a motion system that is compliant and can be integrated in robots thanks to its space-saving design. The device consists of a dielectric elastomer actuator (DEA), which is a membrane made of hyperelastic material like a latex balloon with flexible electrodes attached to each side. The stretching of the membrane is regulated by means of an electric field between the electrodes.

Currently, robots with soft actuators that cannot harm humans are tethered by pneumatic hoses so their radius of motion is restricted. The new soft actuator means that such bulky payloads or tethers may now be superfluous.