Programmable Deformations of Networked Inflated Dielectric Elastomer Actuators

Soft actuators play an indispensable role in producing motions of soft robots. Dielectric elastomer actuators coupled with a fluid/air mass have proved to undergo considerable voltage-induced deformation. To achieve large deformation, a dominant way is to trigger snap-through instability, but the induced instantaneous deformation is not continuously stable, resulting in a limited space for control. This paper proposes a network of inflated dielectric elastomer actuators, interconnected via a chamber, with the advantages to be not only highly deformable but also continuously controllable. Herein, the snap-through instability is suppressed by the initial in-plane prestretch (set to be 3), and the networked design enlarges the actuation range by modulating the inner pressure to postpone material failures. With a large and continuous actuation space, an array of the networked actuators can present programmable deformations. We investigate how to compute the required input voltages for programming desired deformations. We further carry out experiments to show different deformation patterns. This paper represents an important step toward the integration and network of numerous soft actuators, and the potential applications may span shape display and distributed actuation for soft robots.