Hybrid Focre/Position Control And Experimental Investigation Of 5-UPS/PRPU Parallel Machine Tool With Redundant Actuation

PMT (Parallel Machine Tool) is the production of many subjects, including mechanical engineering, electronic engineering, computer science, automatic control and so on. It is one of the most active fields in contemporary science technology. Redundant actuation can help PMT enlarge effective workspace, eliminate the singular configurations, improve its the precision, bearing capacity and dynamic performance. This paper closely combines with needs for development redundancy of PMT and control of a 5-UPS/PRPU parallel machine tool with redundant actuation, focusing on the research of hybrid force/position control system based on the original position control system. The main contributions are as follows:In this paper, the development and characteristics of parallel machine tool are introduced. With that, the development and research status about PMT and PMT with redundant actuation domestic and abroad are expatiated. The production, characteristics and structure of the open CNC system are presented. On this basis, the paper points out the mainly facing issues of parallel machine tool with redundant actuation.They provide theoretical basis that the inverse solutions of 5-UPS/PRPU parallel machine tool with redundant actuation are analyzed and the driving force of redundant branch are solved with the D'Alembert's principle , which paves the way for hybrid force/position control.Based on the original hardware system of the 5-UPS/PRPU parallel machine tool with redundant actuation, two more reasonable hardware systems are designed. Then, the optimum scheme is choosed and a new hardware system is built.Based on the original position control of 5-UPS/PRPU parallel machine tool with redundant actuation, the force control is used to control the redundant branch and the dynamic difference predictive control is proposed. In order to ensure the motion accuracy of PMT, a hybrid force/position control strategy is proposed. Based on the control strategy, the function of this applied software program is developed with Visual Basic 6.0, and the main function is introduced in detail in this paper.The working principle and related parameters setting of Ac servo drive and PMAC PID Notch filter are introduced. The hybrid force/position control system of 5-UPS/PRPU parallel machine tool with redundant actuation is debugged and run, and experiments of the dynamic performance are carried out. The experimental result shows that the hybrid force/position control strategy is accurate and the numerical control software is feasible.