Research On Control For A New-type 3-translation Parallel Robot

Robot with parallel mechanism has many obvious advantages over serial robot. It features high rigidity, great load and high precision. It has wide applications in space flight, medical treatment and numerically controlled machinery.Kinematics relations of parallel robot are analyzed in this project. Methods to draw three-dimensional images of robot's workspace by compiling programs in MATLAB are presented. A completed parallel robot control system is set up and a detailed track is marked out. An efficient robot control program written in VC++ code, which can drive robot to move along any locus in its workspace with high precision, is designed. After analyzing principles for selecting control laws are presented.In the researching aspect of robot control theory,Variable Structure Control theory is introduced at first.The reaching,stability and presence of the sliding mode are mainly analysed;the sliding mode region ,the chatter of the system and the influnce of the approaching are discussed .For the chatter of the Variable Structure Control Systems and the discrete driving form of the step electromotor,a new VSC algorithm are designed to overcome the shortcoming of the traditional chattering of VSC. Both simulation results and theoretic analysis proved the stability and fast tracking performances of the control law. It is shown from the simulation result that the parallel robot system using the proposed control algorithm does not have the chattering problem. The system has good robustness, and is robust to the uncertainties and disturbance, and has good performance in tracking. The high-accuracy real time control of the parallel robot mechanism is implemented.This dissertation adopts the framework of multi-PC and set up the hardware systems with PC and standard control card. And this framework can greatly simplify the structure of the control system and has good reliability and opening ability. On the end, an efficient robot control program written in VC++ code, which can drive robot to move along any locus in its workspace with high precision, is designed.