Highly Integrated MEMS Optical Switch: Multibody Coupling Mechanism

A micro-electromechanical system (MEMS) optical switch, notable for its compact size, precise control, and ease of integration, has emerged as a promising candidate for the safety and arming device (SAD) in laser ignition system (LIS). Integrating functional microstructures and realizing complex logic control functions for LIS safety and arming, however, necessitate a sophisticated multifield and multibody coupling design method. This study focuses on designing a highly integrated MEMS optical switch that incorporates multiple functional structures on a single silicon chip. The integration leverages the dynamic properties of microstructures under multiphysics coupling. A time-sequence matching control circuit is proposed to implement logical control functions such as sensing overload, arming, driving, laser on-off switching, and locking. Consequently, four moveable microstructures are integrated into one silicon chip, and five functions are logically realized. Experimental results demonstrate that the integrated MEMS optical switch can identify accidental (approximately 15 000 g for 0.15 ms) and launch overloads (>5000 g for 1 ms). The optical switch’s motion coupling and time matching control are achieved through sequential voltage loading, with a time interval of 250 ms. The MEMS optical switch can transition the LIS from a safety state to an arming state through four electrical motions within 600 ms. This study is significant for providing a useful SAD for LIS and developing an effective method for multibody coupling and sequential matching control in MEMS devices.