Battery Free Jogger Light

Abstract

This thesis treats designing and building a linear generator which is used to power the Battery Free Jogger Light. This harvester needs to be able to generate power from the movement of a jogger. This Battery Free Jogger Light is meant to be used by people while jogging in dark environments to improve their visibility and thus safety. The complete system consists of the energy harvester which is connected to a full-bridge rectifier. This full-bridge rectifier consists of two LEDs and two schottkydiodes. The bridge is connected to a voltage regulator which provides a constant voltage to a super-capacitor while the jogger is moving. After having the super-capacitor charged to a sufficient voltage level, the super-capacitor is able to power three other LEDs using a clocked-decade counter until the voltage level of the super-capacitor becomes to low. A MATLAB model is created to be able to optimise the parameters of the model to comply with the needs of the rest of the system. To this point the model is able to calculate the voltages which are induced in the harvester. Using the model, a prototype was designed and built which was able to deliver plenty of power to the circuitry of the device. A final prototype of the harvester is designed and built, the harvester is tested in combination with the rest of the system and the complete system is proven to be working.