Energy regenerative shock absorber based on a slotted link conversion mechanism for application in the electrical bus to power the low wattages devices

Abstract

In recent years, using electric buses based on sustainable energy technologies has become very popular due to their advantages of protecting the environment from hazardous pollutants. However, the power supply of electric buses is the most challenging issue and hinders it from making efficient electric buses. In this study, an energy regenerative shock absorber (ERSA) was designed to be employed in the electric bus to harvest kinetic energy from rough road profiles and enhance the efficiency of electric buses. The proposed ERSA is based on a slotted link conversion mechanism to convert linear vibrations to unidirectional rotations of the generator shaft for energy harvesting and comprises four modules: the energy input model, the motion converter model, the model of a generator, and the electrical energy storage model. Firstly, the energy input model induced vibration into the proposed shock absorber; the motion converter model converts linear vibrations to unidirectional rotations using a slotted link conversion mechanism to drive the generator. Subsequently, the generator model generated electric energy stored in the power storage model. The theoretical model was developed, and simulations were performed using MATLAB software; after that, the real-scale prototype was evaluated through an experimental study using a mechanical bench test (MTS machine) under similar parameters. An average output power of 6.591 W with an efficiency of 39.37% was achieved. Moreover, the ERSA system showed a maximum efficiency of 67.7% during sinusoidal excitations of 7.5 mm and 2.5 Hz. Furthermore, the feasibility analysis was conducted to verify the suitability of the proposed system for powering the auxiliary devices in the electric bus. The suggested ERSA can reasonably power light detection, range sensors, stereo vision cameras, an inertial measurement unit, an accelerometer, and a global navigation satellite system.