Power assisting control for electric bicycles using an adaptive filter

This paper considers controller synthesis problem of power assisting system for periodic motions. Most commercial electric power assisting bicycles are using proportional assist to human pedaling torque. However, human pedaling motion is almost periodic and it can be shown that such a strategy is not optimal in the sense of energy efficiency. In our previous work, we observed that pedaling frequency of human fluctuates to some extent. Thus, an adaptive compensation is introduced here. In particular, we propose a power assisting control with adaptive notch filter to suppress the velocity deviation. The effectiveness of the proposed method is demonstrated through numerical simulations.