Research On Key Techniques Of Robot Force/Position Control Grinding And Polishing

Grinding and polishing is an important process for improving the surface quality of workpieces.At present,traditional manual polishing is still the main market,but manual polishing is inefficient and the operation is harmful.This paper combines robot technology and traditional grinding and polishing technology to design a robot force-position hybrid grinding and polishing system,and studies its key strategies such as control strategy,trajectory planning,and process parameters.First of all,a good control model is the key to obtain a high stability and high precision grinding and polishing system.In this paper,the grinding force formula suitable for robot sandpaper grinding and polishing was obtained by deriving and analyzing the grinding force.At the same time,the pressure flow equation of the servo valve and the force balance equation of the compliant actuator at the end of the robot were established based on pneumatic power.Mathematical model of robot grinding and polishing process.In order to improve the performance of the system,a parallel control strategy combining fuzzy PID-based pressure control and robot-end compliant actuator displacement control is used.The simulation in this paper validates the effectiveness of fuzzy PID force control.Secondly,the grinding and polishing trajectory directly affects the machining accuracy.In order to make the robot grinding and polishing system suitable for complex curved surface processing environments,the grinding and polishing trajectory of the surface is planned based on the NURBS(Non-Uniform Rational B-Splines)curve using the constant string height error method,and the robot dynamic posture(Tool Center Point)is used to plan the robot posture to ensure The verticality of the robot surface during grinding and polishing.Offline simulation software is used to verify the rationality of the trajectory planning algorithm.Finally,this paper builds a constant force grinding and polishing platform for FANUC robots.Experiments of plane and surface force and position mixed control were carried out.Considering that the feed speed,abrasive paper size,and grinding and polishing parameters directly affect the grinding and polishing accuracy in grinding and polishing,a single parameter change experiment is designed,and the influence of each parameter on the quality of grinding and polishing is studied,and the plane and surface are verified.The feasibility of using hybrid force-position control algorithm in constant force grinding and polishing.Experiments show that the use of robotic force-level hybrid control for grinding and polishing greatly improves the consistency of the overall quality of the grinding and polishing surface and improves the accuracy of grinding and polishing.