The artificial muscles made by the University of Colorado in Boulder have extreme elasticity, speed and strength, capable of replicating the performance of real muscles and self-repairing, thanks to the introduction of a liquid inside the soft pad that allows the movement of the joint. The study of these electrically activated low cost devices is published in Science. Soft robotics is constantly evolving, the rigid devices of conventional robots are being superseded by a new generation of soft devices that can perform a variety of tasks, including handling delicate objects such as an egg, or even lifting heavy objects. And the 'artificial muscles' made by researchers from the University of Colorado represent a step forward in this sector: they work thanks to a soft donut-shaped cushion, inside which there is an insulating liquid. The bearing is connected to a pair of electrodes and when the voltage is applied, the liquid moves, causing its shell to change shape. In addition to serving as a hydraulic fluid that allows for versatile and faster movements, the use of a liquid insulating layer allows these types of devices to self-repair. "The introduction of a liquid increases joint performance, expansion and contraction, as well as speed and strength", explains Chiara Laschi, of the Biorobotics Institute of the Sant'Anna School and one of the leading experts of soft robotics. "These devices are comparable in strength, speed and efficiency to real muscles". The so-called Hasel actuators, as these artificial muscles were called by the researchers who made them, "combine versatility and performance like no other artificial muscle before" and like real muscles "reproduce the adaptability of an octopus arm, the speed of a hummingbird and the strength of an elephant ”, explains Christoph Keplinger, senior author of the study. The versatility of these new devices paves the way for artificial muscles for robots increasingly similar to humans and the next generation of prosthetic limbs.
