Realization of crawling motion by an underactuated robot with changing constraints

Abstract

Human beings, animals and insects can realize locomotion by changing the supported points of the legs or the contact points of the body. One of the key features of the locomotion is the change of constraint conditions. In this paper we realize crawling motion by an underactuated robot. By changing the location of the fixed point of the robot to the environment, the constraint of the system is changed. A control law based on partial feedback linearization is proposed and stability of the closed-loop system is discussed. We discuss trajectory planning of the robot based on the geometric relation. Experiments have been carried out to demonstrate the effectiveness of the proposed controller.