| In recent years, more and more attention has been paid on the theory and application research of Nonholonomic control systems which is involved in the study of constrained robot, spacecraft etc.. The research has great significance in areas of industry and National force.After summarizing the research background and development of nonholonomic mobile robots this paper primarily deals with the stabilization problem. For the robust trajectory tracking problem with parameter uncertainties in the models further research and experiment have been done to conditions of kinematics, dynamics and with actuator dynamics included respectively, using variable structure control and adaptive control algorithm. One two-wheel driven mobile robot experimental platform used to validate the control methods proposed is developed, the control section is consisted of a PC as â– the central control and computing unit, two Dc servo motor of 80watts and other peripheral circuit, primary experiments are carried out in this installation.One of the important features of nonholonomic systems is that there does not exist any time-invariant smooth state feedback laws to the stabilization problem, therefore time-varying feedback or discontinuous feedback should be utilized. In chapter 2 a piecewise smooth feedback laws is proposed which can stabilize the system to a single point equilibrium from any initial positions.For the kinematics of mobile robot, parameter uncertainties mainly come from diameters of the driven wheels because of wearing between the wheels and the ground in practical application. Moreover to decrease shake when the mobile robot moves around, the wheels are always encircled a layer of rubber, so distortion of the wheel is unavoidable because of the mass of the mobile robot, In chapter 3 variable structure controller and adaptive controller is developed respectively for the robust trajectory tracking problem with parameter uncertainties exist based on the kinematics of the mobile robot.
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