Micro-Energy Harvesting From Automotive Dynamics

Abstract

Most modern vehicles feature some level of automation that contributes to the overall feeling of comfort and safety. Traditional designs are, however, more difficult to apply. In fact, it is a growing consumer of wires for power and communication use, which increases the weight and cost. As a result, new micro-electronics development aims to create systems that do not require external power sources. The automotive systems are exposed to disturbances, which exhibit a vibrational response. This may be harvested into electrical energy. Therefore, the generated energy may be a potential power source for devices, applied to the vehicle. To this end, a micropower generator based on a piezo-electric device is attached to the front suspension arm, an unusual solution in the automotive industry, for extracting energy from vehicle dynamics to power micro-electronic devices and sensors. A numerical simulation from a three degrees-of-freedom model and an experimental vehicular test in different road types were applied to map the energy generated in the harvesting process. The results show that the possibility of generating micro-energy on good quality roads; is low when the International Roughness Index (IRI) is less than 4, and the micro-energy is less than 0.1 mW. However, significant performance is achieved on uneven roads (IRI > 10), that achieve harvested power greater than 0.2 mW. The IRI is a standard method for classifying road roughness. It was found generally that an off-road vehicle is better for harvesting micro-energy because of the high acceleration in the suspension.