Research On A 2-DOF Parallel Robot Control

Parallel robots have the advantages of high rigidity, high burden capacity, no accumulation of positional error, high accuracy, low inertia, so they have become the focus of research in robotics and have extensive and important applications in many aspects such as space flight, busywork in sea and land, computer-aided medical instrument, biological engineering, manufacturing and so on.Low-DOF parallel robots have nice development and application perspective for theirs few drive elements, low cost, simple and compact structure and high practicality value. So it is quite necessary to research them. Based on this, kinematics relations, workspace., trajectory programming and control problems of 2-DOF parallel mechanism, are analyzed and studied in this project.In the research aspect of robot control theory, it is known there exist strong coupling, uncertainties, and great disturbances in robotic system. Meanwhile preferable tracking accuracy is required in tracking control. Hence, it is difficult to carry out tracking control. And sliding mode variable structure control can deal with the non-linear system and provide better robustness for any parameters variety and external disturbances. As a result, a dynamic variable structure controller for parallel robot is designed, and this paper has made an in-depth investigation into the application in the robotic tracking control system. Both simulation results and theoretic analysis proved the stability and fast tracking performances of the control law.In the experiment of numerically controlled parallel mechanism system, this paper adopts the framework of multi-PC and sets up the hardware systems with PC and standard control card. This framework can greatly simplify the structure of the control system and has good reliability and opening ability. In 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.