Vibration Based Energy Scavenging System for Battery Powered Sensor Networks

In recent times, Wireless Sensor Network (WSN) has played an important role for applications in the biomedical, commercial, and military fields. Progress in the Micro Electro Mechanical System (MEMS) made it possible to make sensors that are compact and easy to install, but while this does prove effective in some respects, these sensors operate on batteries that needs replacement regularly. For this reason, an alternative supply of power is necessary to run the sensors more efficiently. This paper proposes that road vibrations can be used to scavenge energy to fuel the batteries, which would then supply power to the sensors. The concept of electromagnetic induction is applied to convert traffic-induced road vibrations into electrical energy. This paper focalizes the process of obtaining maximum output from low vibrations by using a repulsive stack arrangement of magnets rather than a single magnet while still keeping the size of the energy scavenger compact. The output voltages for road vibrations occurring at different frequencies were tested, results have shown that using a repulsive stack approach provided an increase in output voltage when compared to that of a single magnet.