Abstract
This paper describes position control in consideration of tuning of passive compliance characteristic of the antagonistic drive system using rubberless artificial muscle. The rubberless artificial muscle is a pneumatic actuator similar to McKibben artificial muscle. The antagonistic drive system using pneumatic artificial muscle can control antagonistic position. In addition, it has a passive compliance characteristic vary with inner pressure. Therefore, this system has a possibility to control antagonistic position with adjusting passive compliance characteristic. In this paper, we confirm the rubberless artificial muscle has a variable stiffness characteristic experimentally. And we derive an equation model that shows the relation between passive stiffness characteristic and antagonistic force of this system. Next, we explain the contraction displacement linearization system (CDLS). This system decides the inner pressure based on the contraction displacement and contraction force. This system also performs linearization of the nonlinear characteristics of contraction displacement. We confirmed a possibility to realize the antagonistic position control with adjusting passive stiffness of the antagonistic drive system by using this system experimentally.
