A microgripper with a ratchet self-locking mechanism

This paper reports a new design for an electrostatic actuated microgripper with a ratchet self-locking mechanism. The self-locking mechanism enables long-time gripping without continuously applying the external driving signal, such as an electrical, thermal or magnetic field, which significantly reduces the effect and damage on the gripped micro-scale objects that are induced by the external driving signals. The microgripper is fabricated using a silicon-on-insulator (SOI) wafer with a 30μm device layer. The jaw gap is 100 μm, and the ratchet locking interval is 10 μm. A metal wire is successfully gripped to demonstrate the feasibility of the ratchet self-locking mechanism.