Motion Error Analysis of High-speed Parallel Robots

To enhance the operational speed of robots and minimize energy expenditure, a majority of Delta parallel robots employed in the industry have a lightweight design. At high operating speeds, the lightweight construction of Delta robots often causes elastic deformation and vibration. Traditional analysis and control methods for rigid robots do not ensure positioning accuracy of the Delta robot. To address this problem, in this paper we have chosen the WSC-600DJ Delta robot as the subject of our research. Our focus is on analyzing the robot's rigid-flexible coupling dynamics. Firstly, the active and passive arms of the Delta robot are made flexible using Hypermesh software. And then, the rigid-flexible coupled dynamics model of the Delta robot is established in Adams program. Finally, the end effector trajectory is planned in MATLAB using the modified sinusoidal correcting keystone acceleration curve. The driving angle of each active arm is determined via inverse kinematics solutions, which then is imported into Adams for simulation. By comparing the results of modeling the rigid-flexible coupled dynamics of the Delta robot with the theoretical trajectories of the rigid model, we are able to estimate the positioning errors of the robot's actuators caused by the elastic deformation. The results of this study establish a foundation for designing a high-accuracy control system for this particular robot model.