A non-time based tracking controller for multiple nonholonomic mobile robots

Event based controller design was first proposed by Xi (1993), where a suitable non-time motion reference is introduced to represent the desired and measurable system output. It has been successfully applied to many areas such as robot motion control, multirobot coordination, force and impact control, robotic teleoperation and manufacturing automation. In this paper, a non-time based tracking controller for multiple nonholonomic mobile robots is proposed by combining the conventional event based control technique with a biologically inspired shunting model first proposed by Grossberg (1982). The proposed control algorithm can generate smooth and continuous velocity control commands. These commands remove the small tracking error constraints in the conventional non-time based controllers. Thus, these controllers keep multiple robots in a required formation and coordinate in the presence of environment change. The effectiveness of the proposed controller is demonstrated by simulation and comparison studies.