Discussion of alternating muscular activity for the design of an automatic saddle positioning system

This study has been aiming to develop a system that optimizes the mechanical settings of a cycle road racer against rider's physical properties. At present, even skilled cyclist, riders have to rely on their riding feelings and/or advice of trainer, coach, and expert rider. Neither numerical evaluation method nor effective instrument has been used. Therefore, most of cyclists strongly desire the system that helps to find the best positions of saddle and handle only keeping pedaling motion on the experimental device. Now, the authors are constructing an automatic saddle positioning device, in which saddle's horizontal position, longitudinal height, and angle are automatically controlled during pedaling motion. These degrees will be adjusted by the basis of analyzing muscular activity data of lower limbs deeply related in pedaling exercise. Surface electromyography (SEMG) of lower limb is measured to estimate the muscular activity of each muscle. In addition, the muscular activity form of lower limb in pedaling motion is evaluated with principal component analysis. This paper describes a system structure, an experimental protocol, and discusses the experimental results.