The Trajectory Planning And Controller Design Of Similar SCARA Wafer Transmission Robot

With the development of modern industry, the Integrated Circuit (IC) industry has already become the foundation of the world's economy today, the IC equipment industries are driving force and necessary support of the IC industry. As an important part of the IC equipment industry, the merits of the performance of the wafer transmission robot influence the machining accuracy and efficiency of wafer directly. The performance depends on two parts, which are the structure performance and the control system performance of the robot. The main job of this paper is to complete the trajectory planning of the robot and design a reasonable and effective controller for the robot, so as to improve the controlling performance of the wafer transmission robot.Firstly, based on the analysis of the development of trajectory planning at home and abroad and the present situation of research, this paper presents a time-optimal trajectory planning scheme in connection with the similar SCARA wafer transmission robot. During the process of planning, the constraints of kinematics and dynamics were fully considered. Using the iterative method, we obtained the shortest time intervals between adjacent interpolation points. By using five times polynomial interpolation, we finally obtained the smooth track which meets the requirements, and the result of simulation showed that this scheme was feasible.Secondly, we built the dynamic model of the similar SCARA wafer transmission robot, and after further analysis, we found that the system was a coupled nonlinear system. Based on the development of the design researches of robot controller and the present situation of the research, in consideration of the advantages and disadvantages of various means for controlling, and combined with the actual situation, we decided to design the robot controller by using sliding model variable structure control(SMVSC). The simulation results showed that the controller could track the expected trajectory accurately, and the controller of the robot had good robustness when some interference occurred in the system.