Description:With the rapid development of precision manufacturing industries such as aviation, abrasive tools, ships and automobiles, their requirements for product precision and appearance are becoming higher and higher. Six-dimensional force sensors make intelligent polishing operations more and more widely used in modern manufacturing. Industrial robot operations play a very important role in intelligent manufacturing production lines. Traditional position-controlled robots often cannot meet the requirements of high-precision tasks. Therefore, it is necessary to introduce a force control system into robot control to improve the control accuracy of the robot and control contact force. Control to achieve compliant and constant force polishing of industrial robots. This paper designs an industrial robot constant force polishing system based on force control algorithm, which consists of hardware such as robot body, six-dimensional force sensor, pneumatic polishing machine, electrical proportional pressure regulating valve, constant force polishing device, robot controller and PC. According to the structure and performance requirements of the polishing robot control system, the structural design of the industrial robot constant force polishing workstation and the construction of the experimental platform were completed, and the constant force polishing device was designed according to the requirement for constant contact force during the polishing process. The force control algorithm involved in this system is based on fuzzy PID control, using a six-dimensional force sensor to collect the external force signal received by the robot end as input, and a constant force polishing device installed on the flange at the robot end as output. The additional force signal conversion module, filtering module and gravity compensation module in the control system process the collected analog signals to obtain the actual contact force between the polishing tool and the workpiece; then a mathematical model is established for the system, and the established mathematical model is simulated and analyzed based on MATLAB to verify the feasibility of the force control algorithm. The superiority of the designed polishing force control algorithm was verified through comparative tests; different contact forces were set on the system to verify the stability of the system's contact force change range during the polishing process, and the accuracy of the six-dimensional force sensor in the polishing force control algorithm was laterally verified; Finally, the roughness of the workpiece before and after polishing was compared to verify the feasibility of the polishing control algorithm of the system. Using the force control algorithm of this system, compliant position compensation can be realized during the polishing process, and a constant contact force between the polishing tool and the workpiece can be ensured, thereby completing the constant force polishing operation of the robot to control the compliance of the workpiece. This system can not only achieve the requirement of constant contact force control during the polishing operation, but also take into account the flexibility of the robot and can polish large and complex curved workpieces.