| The parallel manipulator used in free-form surface polishing process has becomea kind of trend, How to improve the accuracy of polishing has become an importanttask in parallel polishing manipulator research. The parallel polishing manipulatorsystem with dynamic feed-forward control which can predict the polishing headvelocity and acceleration, so that the system can respond quickly when it’s trajectorydeviates from a given trajectory. It can improve the system response speed and controlprecision. This will guarantee the practical application and commercially of theparallel polishing machine tool. So the dynamic modeling and dynamic control is animportant part in improve the accuracy of parallel polishing manipulator and have animportant practical significance.This thesis bases on five degree of freedom parallel polishing manipulator, thedynamics equations of parallel polishing manipulator are built up and a simulationexample is made to show in MATLAB. And the optimal controller is designed whichunder the action of random disturbances.Firstly defined the D-H frame for each leg of the parallel polishing manipulator,and then built up the dynamics equations of the parallel polishing manipulator byNewton-Euler method. The dynamics equation in matrix form is given out. Furtherobtain the state equation of the parallel polishing manipulator system.Secondly, base on the state equation of the parallel polishing manipulator system,designed the computed torque controller and optimal controller, and then simulaterespective in MATLAB. Obtain the simulations result respective with disturbance andwithout disturbance, analysis the actual control effect and anti jamming ability ofthese two kinds of control methods.Finally, analyses the parallel polishing manipulator system in randomdisturbance and designed reduced-order observer for random disturbance andreference output. Then obtain the optimal controller for the parallel polishingmanipulator system and simulates it in MATLAB. |
PDF Full Text Request