Optimization design and shock calibration of pendulous high-g micro-machined accelerometer

A kind of pendulous high-g micro-machined accelerometer was designed. Cruciform torsion beam was applied to reduce cross-axis sensitivity, and comb structure was used as stopper and damper. The micro-structure parallels 6 sensing units to improve initial capacitance. Based on finite element analysis, the micro-structure's natural frequency is about 56 kHz with modal separation ratio more than 4. It can resist 1E5 g shock acceleration and the micro-structure's sensitivity is 8.94E-6pF/g. The accelerometer's fabricated by silicon on glass (SOG) technology, and its single-side initial capacitance is about 3.6pF. The measurement bandwidth of ring diode capacitance detection circuit was analyzed and a high g accelerometer's detection circuit was designed. Calibrated by Hopkinson bar, the accelerometer's nonlinearity is 2% of 2E4 g range, and the scale factor is about 24.5μV/g with 5V supply. ©, 2015, Chinese Vibration Engineering Society. All right reserved.