Desing And Simulation Study Of A Light-weight And High-speed Parallel Manipulator

With the rapid development of robot technology, the field of application of parallelmanipulator is more and more widely, so the parallel manipulator has become a newhotspot in the field of robotics today. Aiming at the problem that the parallelmanipulator mechanism is more complicated than the traditional serial manipulator,funded by the research fund of robot of UESTC, Taking a light-weight and high-speed3DOF Delta parallel manipulator for example, the co-simulation technology isinvestigated on the parallel manipulator research on its kinematics analysis, singularityanalysis, static and dynamic characteristics of finite element analysis, and controlstrategy study.Firstly, this paper analyzes the working principle of3DOF parallel manipulatormechanism, and carries out its kinematics analysis. Among then, the inverse kinematicsof3DOF parallel manipulator is obtained through the analytical method. And theforward kinematics of it is obtained through the geometric method. The robotkinematics inverse solution of the analytical method by geometry obtained its ForwardKinematics. In addition, this paper discusses the singular configuration of3DOFparallel manipulator that could happen occur.Secondly, the finite element analysis of static and dynamic characteristics of3DOFparallel manipulator is presented in this paper. Combined with the co-simulationtechnology to achieve data exchange interface between Pro/E and ANSYS software, thispaper builds the finite element analysis model of3DOF parallel manipulator, thencarries on its static stiffness and modal analysis. Through the static stiffness analysis,researching the relationship between different position and structure performance of thelight-weight and high-speed parallel manipulator, found that the end actuator is moreoff-center and close to the workspace boundary, the structure performance is morepoorer; Through the modal analysis, researching the modal shape of former6order ofthe light-weight and high-speed parallel manipulator, found that the modal shape areconcentrated on the follower arm. Then, this paper presents some method to optimizethe structure of the follower arm design, such as increase the virtual constraint in the follower arm, increase the sectional dimension of the follower arm, select low-densityand high-strength material, to avoid deformation and vibration of the parallelmanipulator in high-speed movement.Thirdly, based on fully research SimMechanics toolbox and method to build blockdiagram for mechanical system, this paper applies Pro/E software and SimMechanicsLink interface tool to build SimMechanics block diagram model for the parallelmanipulator, and then carries on the simulation analysis for its kinematics and dynamicsbased on this model.Finally, this paper researches different control strategies of the parallel manipulator,and then achieves a virtual reality co-simulation simulation platform. Determined thecontrol tasks of3DOF parallel manipulator, this paper respectively studies and designsPID controller and fuzzy-PID controller that are used to achieve a space spiral curvetrajectory tracking simulation of the parallel manipulator. Meanwhile, according to thetrajectory tracking RMSE (Root-Mean-Square Error) to compare and analyze theperformance of the two controllers, the results show that self-adapting fuzzy-PIDcontroller can be more suitable for controlling the parallel manipulator that ismulti-input multi-output strongly coupled and nonlinear system.