| The parallel robots, a new robot in structure, has the advantages of stiffness, big-load capability, small error, high precision and a good dynamic performance compared with the traditional serial robots. Now, the parallel robots have been widely used in aerospace, ocean bottom work, computer-aided therapy, precision manufacture, virtual-axis lathe as well as the micro-electro-mechanical systems fields. The parallel robots are becoming a hotspot in study due to its widely applications. As the parallel robots are highly nonlinear, strong coupling and easily-changing systems, the traditional control methods have become less effective. From the view of the control point, there is always a big challenge to seek a good control theory and algorithms of high reliability, robustness, self-adaptability, intelligence and user-friendly to meet the control needs of such complex systems. So it is still difficult and hot in the control area of the parallel robots. The study on the control strategy of the parallel robots in this paper, not only has the high practical value, but also has the academic value.First, the overview of domestic and international research on this subject as well as the development of profiles has not been done, so it is necessary to discuss the study of the content, purpose and the significance. Then with the study of the 6-PTRT parallel robot, it has also analyzed and designed the hardware of the control system. Besides, it analyzes the parallel robot kinematics from the perspective of the relevant robot theories, which sets the foundation for the parallel robot motion control. Secondly, it has established the mathematical model of the control subjects from the control point after the introduction of the parallel robot control. Then it uses the RBF neural network’s ability to any nonlinear function approximation, to find self-learning and self-tuning of PID parameters, which has improved the quality and the precision of the systems combined with the method of the PID control strategy. Finally, from the characteristics of the control system, it has also designed the control software using the VC development tool, which control the parallel robot’s movement. The control results meet the desired requirements and further demonstrate the above-mentioned control method in the parallel robot system. |
