Chaos And Its Control Of Redundant Robotic Mechanisms

The redundant robot system is a highly coupling nonlinear dynamic system, with plenty of dynamic performance. And it is meaningful to study the chaotic motion in the system and its use or control to improve the robot's structural and controller design and working performance. In this thesis, research on the chaotic motion and control of redundant robot has been done.Firstly, the basic theories of chaos are introduced. Some effective numerical methods such as phase plot method, Poincare maps method and the largest Lyapunov exponent method for analyzing the chaotic motion in redundant robot systems are presented.Secondly, the relations between the self-motion of a planar redundant robot under the PD controller and the different Jacobian matrix methods for solving the inverse kinematics are gotten for the first time when the end-effector traces a closed-path repeatedly in the workspace with avoiding singularity, obstacles, and minimal joint torques planning respectively; The relations between the self-motion of a spatial redundant robot under the P or PD controller and the different resolved motion control methods for solving the inverse kinematics are obtained for the first time when the end-effector traces a closed-path repeatedly in the workspace.Finally, the delayed feedback based control method is proposed to control the chaotic motions in above-mentioned planar and spatial redundant robots for the first time. The disturbance variable, the delayed time " ", the feedback weight factor "k" and the time of adding delayed control signal are some key parameters for good chaotic control in the method.The software for analyzing and controlling the chaos in theabove-mentioned redundant robots is coded into Matlab.