Posture Stabilization of Quadruped Walking Robot, PongBot with Disturbances

This paper describes the posture stabilization of the quadruped walking robot, PongBot, in the presence of the disturbances. The proposed posture stabilization is mainly composed of the two sub-controllers: body balance controller and body moving controller. The body balance controller is working at all times in the background, and the activation of the body moving controller is determined according to magnitude of disturbances. First, the body balance controller, which is mainly effective for small disturbances, maintains the level body through the optimal distribution of the vertical ground reaction forces on the feet. The body moving controller, which is primarily for large disturbances, performs the posture stabilization through the horizontal body movement, and it is activated together with the body balance controller. Finally, the performance of the proposed method was experimentally verified by using the quadruped walking robot, PongBot, in the presence of the changing ground slope and external impacts.