Soft robotics actuators are “fast as a hummingbird, strong as an elephant”

The development, from engineers at the University of Colorado at Boulder, is aimed at enabling robots that will work closely with humans and new generations of prosthetic limbs capable of life-like movement and strength. “We draw our inspiration from the astonishing capabilities of biological muscle,” said Dr Christoph Keplinger, a mechanical engineer and director of the lab at the university’s College of Engineering and Applied Science

Like many soft robotics devices, the Keplinger group’s actuators combine stretchy elastomers with liquids. Called HASEL (Hydraulically Amplified Self-healing Electrostatic) actuators, Keplinger’s team has developed three types, which they describe in papers in the journals Science and Science Robotics.

One HASEL device described in the Science paper consists of a doughnut-shaped elastomer shell filled with a slightly viscous liquid like rapeseed oil and hooked to a pair of opposing electrodes; when a voltage is applied across these, the liquid is displaced and the shape of the shell responds accordingly. Such a device could form the basis of grippers that can handle delicate objects like raspberries or raw eggs without damaging them.