Actuation and sensor integrated self-powered cantilever system based on TENG technology

Actuation and sensors for driving and monitoring of cantilever beam system are of most significant in the field of micro-electro-mechanical systems (MEMS). However, the AC voltage driving module and piezoelectric materials used in cantilever highly raise the system complexity and costs. Here, we propose a motion-triggered cantilever beam (MC) accompanied by an integrated real-time oscillation-monitoring sensor (ROS) designed based on the principle of triboelectric nanogenerator (TENG). Utilizing the periodically built and neutralized high DC voltage during the operation of the freestanding mode TENG, the low-frequency mechanical motion (down to 5 up to 200 mm/s) can be converted into high-frequency oscillation up to 100 Hz. Different from AC trigger method that requires excitation frequency matching the intrinsic frequency of the cantilever, DC actuation strategy is universal to all kinds of cantilever systems. Additionally, based on the single electrode mode TENG, the integrated self-powered ROS shows ultra-high sensitivity (223 mV/mm compared with 72 mV/mm for laser micro-motion meter). Finally, a self-powered micro-weighing system based on MC and ROS is demonstrated. This work exhibits notable advantages of using TENG technology for both power supply and sensing in MEMS applications.