Micro cam system driven by electrostatic comb-drive actuators based on SOI-MEMS technology

Abstract

This paper reports a design and fabrication process of a micro cam system (MCS) with a flat-faced translating follower. The cam rim with cover diameter of 2.4 mm is driven by four electrostatic comb-drive actuators (ECA). Reciprocating motion of the ECAs is converted to unidirectional rotating movement of the outer cam rim through ratchet and anti-reverse mechanisms. The MCS was fabricated by using SOI (silicon on insulator) wafer with 30 孠thick device layer, and only one mask. Driven by periodic voltage with different frequencies, the performance of the MCS was successfully tested. In our experiment, when the system was run by the minimal driving voltage of 80 V, the obtained stroke of the follower was 160 孮 In addition, the system can run smoothly while applying the force of 31.3 厠on the follower. The MCS can be applied in micro valve structures, in micro assembling systems, etc.