Wall-climbing microbots with ultrafast de-adhesion

Adhesion technologies enable robots to perform specialized tasks such as climbing and grasping, making them valuable for industrial applications. Electroadhesion (EA) stands out for its wide applicability, simple control, and low power consumption among various adhesion methods. However, its practical use is limited by the slow de-adhesion speed. In this study, we propose a novel method by introducing a self-excited pulse module into the driving circuit of EA pads. During the de-adhesion process, the residual charges induce self-excited vibrations of the cantilever beam within the module, generating an external pulsed electric field that matches the EA pads. This external field neutralizes the residual electric field, enabling ultrafast release. The proposed method elevates the release speed of EA pads by more than 90 times and reduces the adhesion force decay after repeated use from 56–11%. We developed an ultrafast wall-climbing microbot based on this method, achieving a climbing speed of 4.44 cm/s (with a step frequency of 2.2Hz), which is 5.6 to 25 times faster than the robots using traditional release methods. Furthermore, we developed the first untethered electroadhesive microbot by integrating a high-voltage power system.