基于视觉与边界元法的复杂曲面砂带磨削接触状态快速获取

A Fast Method to Obtain Local Contact Status in Belt Grinding of Complex Surface Based on Vision and BEM

机器人砂带磨削具有高的加工表面质量与效率,但是在加工复杂曲面部件时,难以确定的局部接触状态导致加工过程的精度难以保证,限制了其在高端产业的应用。目前的局部接触状态计算方法难以满足加工中对计算效率的要求。因此,本研究首先对比分析了FEM与BEM在计算接触状态方面的结果,提出采用机器视觉识别砂带上的磨削痕迹得到磨削区宽度,并将其作为BEM的边界条件,最终实现了局部接触状态的快速获取。该方法能够在1 s内计算得到18 mm×18 mm区域大小,精度0.2 mm点云轮廓的接触状态,与FEM计算结果对比,最大误差不超过5.6%。

Robotic belt grinding has higher cutting efficiency and surface quality.However,implicit local contact status makes it is difficult to guarantee processing accuracy and hinders its application in high-end industries,especially when the workpiece has complex contour.And the current local contact status computing methods are inefficient and cannot meet timeliness requirements.Therefore,after analyzing results of FEM and BEM in computing the local contact status,this paper acquires the contact width on abrasive belt based on machine vision.Then the contact width is used as the boundary condition of BEM.Finally,this paper has achieved the contact status fast calculation of the point cloud within 18 mm×18 mm area with the accuracy of 0.2 mm and in 1 s.Compared with FEM calculation results,the maximum error of the contact status obtained by the novel method is no more than 5.6%.