Path Planning And Optimization Of Robotic Belt Grinding System

Industrial robots are now widely used in abrasive belt grinding process,but mainly still use the "teaching-playback" model,once the workpiece shape is complex,it is bound to increase the teaching workload,while inevitably reduce the quality of robot grinding.In order to improve the flexibility and processing quality of robot belt grinding,it is necessary to automatically generate high quality and high efficiency robot belt grinding path,so it is necessary to automatically plan and optimize the path of robot belt grinding system.In this paper,the path planning and optimization of the robot grinding system are carried out.The planning of the workpiece grinding path,the collisionless optimization of the robot motion path,the sort optimization of the robot motion path,and the realization and experimental verification of the path planning and optimization system of the robot grinding system are carried out.Firstly,the path planning method of robot belt grinding is studied.Based on the 3-D model of the workpiece,the data of the surface to be grinding is extracted and pretreated.The method of calculating the cutting step length in the discrete arc parameter domain is proposed,which overcomes the shortcoming of the accuracy and efficiency of the cutter contact path calculated by the curvature estimation method.Based on the iso-scallop method,the grinding path of the abrasive belt is generated.Based on the ball-end cutter path interval calculation method,according to the characteristics of abrasive belt grinding to modify,calculate the path interval of abrasive belt grinding.In the calculation of offset cutter contact line,a new algorithm based on mapping method and contour extraction method is proposed to solve the problem of curve self intersection.Finally,the grinding path of surface is generated,and is transformed into the robot motion path.The experimental results show that the grinding path can be used to achieve the high quality of the grinding surface.Secondly,the method of collisionless optimization of robot motion path is studied.Aiming at the possible collision phenomenon during the robot belt grinding of the workpiece,the principle of collisionless optimization of the robot motion path is studied,and a collisionless optimization method based on the collision layer method is proposed.In theprocess of the grinding path of the workpiece into the robot motion path,a collision layer is formed,and the optimization curve is quickly found in the collision layer based on the neighborhood search method and the recursive method,which greatly reduces the number of collision detection,and generates a collisionless robot motion path according to the optimization curve.Simulation and experiment show that the method can quickly and accurately generate a robot motion path without collision,and realize the robot belt grinding workpiece without collision under the premise of ensuring the processing quality.Finally,the optimization method of robot motion path sorting is studied.when the robot has multiple motion paths,optimizing the order of motion path of the robot in order to reduce the invalid travel in the robot motion path conversion.The problem of robot motion path optimization is modeled and transformed into a generalized traveling salesman problem.Three kinds of strategies are used to improve the basic ant colony algorithm,and the optimization ability and convergence speed of ant colony algorithm are improved by using multi-ants,multi-stage search and neighborhood search.The simulation results show that the length of the empty stroke in the machining process is reduced to 27.25% before optimization,and the improved ant colony algorithm is improved by 5.13% compared with the basic ant colony algorithm.