Design, Modeling, and Road Tests of Electromagnetic Energy-Harvesting Shock Absorbers

This paper presents the design, modeling, bench experiment, and road test of a retrofit regenerative shock absorber based on a permanent magnetic generator and a rack-pinion mechanism for the purposes of energy harvesting and vibration control. Results show that variable damping coefficients and asymmetric feature in jounce and rebound motions are achieved by controlling the electrical load of the shock absorber. Improved efficiency and reliability are achieved by utilizing a roller to guide the rack and preload on the gear transmission to reduce the backlash and friction. A peak power of 68 Watts is attained from one prototype shock absorber when the vehicle is driven at 30 mph on a fairly smooth campus road.