Multi-Threshold Inertial Switch for Quantitative Acceleration Measurements

This paper presents a multi-threshold inertial switch demonstrated experimentally and through simulation. A laterally-driven multi-threshold inertial switch based on SOIMUMPs has been fabricated. The device has been tested by a drop-table test system under different shock accelerations with various amplitudes and pulse widths. In addition to experimental data, finite element simulation has been used to further assess the device’s performance. The designed switch is a 2-axis device capable of triggering in all directions in a single plane. This work demonstrates that the designed inertial switch with 3 threshold levels can perform quantitative acceleration measurements while saving power when not activated. The multi-threshold inertial switch can sense a shock range of 800g–2600g. The same device principle can be extended for a higher number of bits. The axial disturbance performance shows that the inertial switch has high single-axial sensitivity and low axial cross-talk.