Research On Constant Force Control Of Robot Grinding

When the industrial grinding and polishing robot grinds the workpiece,the grinding contact force is one of the important factors affecting the quality and efficiency of grinding,and the unstable contact force is one of the main reasons that the damaged parts and make them unqualified.This paper improves the control mode of the robot based on a single position parameter,then establishes an open control system for industrial robots,and designs an adaptive constant force control algorithm for the robot in this open control system to keep the contact force constant during the robot grinding process.And the material removal depth model of robot belt grinding was established.The designed constant force control algorithm is further optimized through the self built robot experimental platform,and the accuracy of the established material removal depth model is verified.Firstly,based on the mechanism of abrasive belt grinding and polishing,the ideal material cutting model of single abrasive was established and analyzed.Through analysis,the influence trend of the normal pressure of robot grinding on material removal was obtained,and the normal pressure of grinding,abrasive belt grinding speed and workpiece feed speed are taken as the main process parameters that affect the grinding effect.In order to realize the robot's constant control of grinding pressure,the PID constant force control algorithm was designed,and it is realized by programming and simulation.According to this,the overall scheme and structure design of the open control system are proposed.Secondly,according to the composition of the abrasive belt itself and the abrasive belt contact wheel have elastic characteristics,using the above three process parameters as variables,combined with the Preston empirical formula and the Hertz elastic contact theory,a material removal depth model for robot abrasive belt grinding was established.And use MATLAB to simulate it,and get the influence law of three process parameters on the theory of material removal depth of belt grinding.Then,taking the industrial real-time Ethernet as the physical connection layer,using the UDP/IP data transmission protocol and the dual thread parallel communication technology,the robot experiment platform based on the RSI application program communication was built.Using VS2010 tool set,the software ofrobot open control system based on C + + is developed,and the self-designed single neuron self-adaptive PID constant force control algorithm is embedded in the control software,which realizes the robot's effective constant force control of grinding process.Finally,aiming at the single neuron coefficient K in the constant force control algorithm,a variety of constant force control experiments are designed.According to the experimental results,a constant force control algorithm with single neuron coefficient K self-adjusting was proposed,which further improves the adaptability and robustness of the controller.According to the derived expression of Preston constant,the Preston constant of the experimental platform was obtained by orthogonal test;then,using three process parameters as variables,a single factor grinding experiment was designed to verify the accuracy of the material removal depth model.