A Low-G Threshold Mems Inertial Event Sensor with Friction-Enabled Mechanical Latching

This paper reports the first demonstration of an energy-pre-storage MEMS inertial event sensor utilizing a friction-enabled self-latching mechanism to achieve low-g threshold triggering. The device incorporates two key innovations: (i) an event-sensing method that leverages pre-stored elastic energy to assist inertial triggering and maintain sustained mechanical contact for a stable electrical connection; and (ii) a friction-enabled mechanical latch that combines weak inertial inputs with stored elastic energy to overcome static friction, thereby enabling low-g threshold triggering. Experimental results demonstrate reliable triggering at$5 \mathrm{g}\left(\mathrm{g}=9.8 \mathrm{m} \cdot \mathrm{s}^{-2}\right)$without the need for continuous power delivery or auxiliary circuits, offering a sustainable and autonomous solution suitable for large-scale, energy-constrained sensor networks in Internet-of-Things and embodied-intelligence applications.