On Energy Harvesting from a Vehicle Damper

Conventional hydraulic dampers reduce vehicle vibration by converting the vibration energy into heat. In addition to wasting energy, the fixed damping characteristics of these dampers cannot adapt to different road conditions. As we know, a suspension with tunable damping provides a more comfortable ride. However, previous works regarding tunable regenerative dampers, which usually consist of a single generator, have some shortcomings, including wasted energy and a limited range of tunable damping. With these problems in mind, a new design principle with multiple controlled transducers is discussed in this article. By controlling the number of switched on transducers and adjusting the value of the external resistance, the damping characteristics can be fine-tuned according to the requirements. With this new design principle, a regenerative damper cannot only tune the damping behavior over a broader range but also harvest as much vibration energy as possible. The design principle was verified by building and testing two different prototypes. The experimental results showed that these two dampers could achieve nearly linear turning of the damping coefficient and harvest more electrical power from vibrations than other type of energy-harvesting dampers.