Electrostatically Induced Programmable Vibro-Impact Motion in Multiple Degrees of Freedom

The unique asymmetric vibration motions of vibro-impact devices make them valuable in various robotics and industrial applications. However, achieving bidirectional vibro-impact motions in multiple degrees–of-freedom (DoF) remains challenging due to the inherent restrictions in conventional rigid actuators and fixed constraint designs. Emerging soft robotic technologies have enabled programmable change in stiffness between rigid and compliant states, and realizing actuation in multiple DoFs with a single actuator. This article presents the first 3-DoF programmable vibro-impact device based on innovative soft robotic technologies of electroadhesive (EA) clutches as the stiffness programmable constraints and a 3-DoF dielectric elastomer actuator (DEA) as the multidirectional vibration motion generator. Two unique asymmetric stiffness programming modes of the EA modules are demonstrated, and the programmable vibro-impact motions of the EA-DEA system in 3-DoF are analyzed in both simulations and experiments. Compared with the state-of-the-art, our EA-DEA can produce comparable peak impact forces (4 N), but at a substantially faster actuation frequency (100 Hz), lower power consumption (< 0.7 W), and a lightweight of ∼30 g. A multidirectional vibro-tactile feedback device, a multidirectional vibrating platform, and a multidirectional crawling robot based on the EA-DEA are demonstrated to showcase its potential applications.