Design, test and analysis of a threshold-value judging mechanism in silicon-based MEMS safety and arming device

A silicon-based micro-electro-mechanical systems (MEMS) safety and arming (S&A) device is presented, which exhibits high precision and reliability and is based on an integrated design concept. The threshold-value judging mechanism, which is a key component of the MEMS S&A device, was designed and fabricated by a silicon process. The threshold-value judging mechanism was studied via cantilever beam theory and verified by simulation and experimental methods. The experimental results show that when the centrifugal acceleration exceeds 52 320 g, the threshold-value judging mechanism initiates arming. The measured g-value for fracture of 52 320 g differs by 3.2% from the mathematical analysis and by 8.4% from the finite-element analysis results obtained herein. Therefore, the results obtained experimentally, by simulation and theoretically, are consistent, and indicate that the threshold-value judging mechanism meets the expected criteria. Furthermore, because of the fragile characteristics of silicon, the feasibility of the silicon-based structure as a functional component in the MEMS S&A device is confirmed.