Self-powered And Autonomous Vibrational Wake-up System Based On Triboelectric Nanogenerators And MEMS Switch

With the rapid development of the Internet of Things technology,wireless sensor network nodes have been widely used in environmental monitoring.The huge number and broad distribution of sensor nodes make the sustainable energy supply face great challenges.Traditional sensor nodes use batteries or wired power supply,which has problems such as limited service life,environmental pollution,and complex wiring.These problems increase the cost of wireless sensor nodes,especially in harsh environments and remote factories,which greatly limits the large-scale laying of sensor nodes.Self-powered technology can harvest mechanical energy from the environment,which provides an energysaving and environmental conservation method to solve the energy supply of sensor nodes.Triboelectric nanogenerator can convert mechanical motion into electrical signals,which could harvest the mechanical energy of the surrounding environment and identify the information of mechanical motion as a sensor.This provides a new solution for the realization of self-powered weak-up system.Here,a self-powered and autonomous vibrational wake-up system(SAVWS)based on triboelectric nanogenerators and micro-electromechanical system(MEMS)switch is proposed.The system could harvest the mechanical energy of vibration in industrial environments,monitor the acceleration of vibration,and use the harvested mechanical energy to send abnormal vibration alarms.By receiving and analyzing the alarm signals,the real-time monitoring of mechanical equipment acceleration is finally realized.The specific research contents are as follows:First,a triboelectric nanogenerator with integrated energy harvesting and sensing signal collection was designed and fabricated.It consisted of two vertical contact-separation triboelectric nanogenerators,supported by springs,and had a good response to weak vibration,which was suitable for harvesting vibration energy and capturing vibration information.Then the output of the integrated triboelectric nanogenerator to the different vibrations was tested.The results showed that the triboelectric nanogenerator had a good response to the acceleration of vibration,and could effectively harvest vibration energy and convert it into electrical energy.Then the Self-powered and autonomous vibrational wake-up system was built by using the triboelectric nanogenerator.The system used a MEMS switch to wake up the wireless transmitter module by monitoring the change of acceleration.Finally,the vibration environment of the factory was simulated to study the performance of the system in the laboratory.The experiment proved that the system could monitor the vibration acceleration and reported the abnormal acceleration through a wireless transmission module without any external power supply.