Design of an open spot welding robot control system

LIU Lei, HU Guodong, LIU He, WAN Jun
(Chery Automobile Co., Ltd., Wuhu 241009, China)

Abstract: To resolve the abuse brought by close control system, and to consider the technical requirements of robot spot welding, an open spot welding robot control system was designed, the structured hierarchical system and functional modules were provided. Programmable multiaxies controller(PMAC) acted as motion controller, in which robot kinematics arithmetic and servo arithmetic were completed. Servo amplifier adopted the speed control mode. The position loop arithmetic was completed in PMAC, and the speed loop arithmetic was implemented in servo amplifier. The offline programming and the threedimensional simulation were realized. The experimental results show that this structured hierarchical system greatly improves the system independence and flexibility of software and hardware, and the control mode adopted in this system enhances speed loop rigidity and antijamming capability. The offline programming improves the weld quality and work efficiency, and this design meets the highspeed and accuracy requirements of the field applications.
Key words: spot welding robot; control system; programmable multiaxies controller(PMAC); VC