Research On Displacement Trajectory Tracking Control Based On 3 - RPS Parallel Manipulator

In recent years, the word of the parallel robot has been no stranger to the wide range of applications in various fields, mainly due to the overall stiffness is relatively largely, actuator host strong running operation is relatively simple. But at the same, it is a MIMO system, and there is a serious nonlinear and strongly coupled, which largely affected the broader application of parallel robots.In this paper, through research the3-RPS parallel robot trajectory tracking control, comparative and analysis of the effect of the different control strategies generated by the trajectory tracking control for the selection of better control measures to improve the performance and quality of the parallel robot system, and provide an important theoretical basis. The contents of this paper are mainly the following aspects:First, analyze the kinematics of the parallel robot. Applying the coordinate transformation method, the Euler angles, and closed solution, it has analyzed the position inverse solution, and draw the parallel robot amount of elongation of the driving lever and the movable position of the platform, and used screw theory to analyze the degree of freedom, the Jacobian matrix, singularity, and verified the method which calculate the degree of freedom of the parallel mechanisms is correct, through the use of the traditional formula of Kutzbach-Grubler. The kinematic analysis provides the theoretical basis for the agency in Matlab modeling and obtaining the driver displacement desired trajectory.Second, analyze the dynamics of the parallel robot, analyzed the driving force of the parallel robot the constraints of torque, and the force of the moving platform branched. Determine the major components of the hydraulic servo system and its transfer function. Plan the parallel robot’s trajectory, according to use the displacement of the parallel robot’s three chain drive pair as the expected trajectories, on the basis of the calculated inverse position, and applying Matlab to model and simulate to grain the expected trajectories of the three driver pairs.Then, design the conventional PID controller, fuzzy controller, and fuzzy PID controller for the parallel robot. That provided important theoretical basis for the trajectory tracking control simulation analysis of the parallel robot.Finally, on the basis of the kinematics and dynamics, applied the designed controller, and based on Matlab simulation software to simulate and analyze the trajectory tracking control, so as to verify to validity of the controller and comparative analyze the control algorithm accuracy and concluded.