Visual servoing with LQR control for mobile robots

This paper studies visual-servo control for robust motion of a wheeled mobile robot. First, the kinematic model of a wheeled Pioneer DX3TM mobile robot with a CCD camera is generated. Second, a linear quadratic regulator (LQR) law is developed to control the motion of the robot to a goal location (grasping location). The derived controller, which is a form of image-based visual-servo (IBVS) controller, guarantees asymptotic stability of the closed-loop system. Furthermore, in order to cope with an important robustness issue in visual servoing - maintaining the visual features in the field of view of the camera - a velocity constraint is set in the implementation program. The developed approach is implemented in a laboratory mobile robot and tested. Both simulation and experimental results show good performance with respect to robustness, speed of response, and accuracy. The presented mobile manipulation system is intended for use in a multi-robot cooperative project.