Dynamic Modeling And Research On Trajectory Tracking Control Of 3-DOF Parallel Manipulator

Parallel mechanism has been widely used by experts and scholars because of its large capacity,high motion precision and flexible structure.Parallel mechanism has been widely used in the fields of fire fighting robot,driver simulation module,swing platform and so on.In this paper,the power of the national science and technology support program,which has independent intellectual property rights,can be further applied to the multi foot robot,the multi rod support dynamic load platform,the multi freedom manipulator and the key component of the multi degree of freedom manipulator,which has high carrying capacity and high precision,has been powered by a new type of weak coupling 3-DOF parallel mechanism.Study of modeling and trajectory tracking control.The main work of this article is as follows:First,on the basis of the detailed analysis of the configuration of the(U+UPS)P+UPS 3-DOF parallel mechanism,the constraint relationship between the branches is analyzed.The Lagrange method is used to establish the dynamic model of the 3-DOF parallel mechanism,which lays a foundation for the follow-up study of the trajectory tracking control algorithm.Secondly,aiming at the trajectory tracking problem of the 3-DOF parallel mechanism,a fuzzy PID controller is designed.The controller uses fuzzy algorithm to adjust the PID parameters.The validity of the fuzzy PID algorithm is further verified by numerical simulation.Compared with the simulation results of the traditional PID control algorithm,the controller effectively reduces the tracking error of each chain.Thirdly,in order to improve the tracking accuracy and anti-interference ability of the 3-DOF parallel mechanism,a fuzzy sliding mode controller is designed.The controller adjusts the parameters of the sliding mode controller by fuzzy algorithm.The simulation results show that the fuzzy sliding mode controller based on the exponential convergence law has the advantage of reducing the trajectory tracking error and improving the anti-interference force.Finally,aiming at(U+UPR)P+UPS parallel manipulator,the experimental platform of 3-DOF parallel manipulator is designed and built.The platform is mainly composed of 3-DOF parallel manipulator,data acquisition card,signal converter,servo motor,servo driver,host computer and motion controller.Based on the experimental platform,fuzzy PID control algorithm and fuzzy sliding mode control algorithm are adopted to track the 3-DOF parallel manipulator.The experimental results show that the dynamic model of the manipulator is reasonable and effective.The designed control scheme is feasible and the experimental platform is correct.The 3-DOF parallel manipulator can track the trajectory under the function of the designed control algorithm.