一种机器人砂带磨削的路径规划方法(英文)

机器人砂带磨削系统具有弹性接触和宽行加工两个显著优点,被广泛应用在具有复杂工件的终加工领域,提高表面质量和加工效率。有关在曲率约束下的磨削路径规划研究较为少见。由于工件与接触轮之间存在复杂的弹性接触,因此,机器人磨削路径可以利用接触运动学的一般方法来求解。机器人砂带磨削过程且需要满足一般的砂带磨削工艺要求,其中最重要的是保证接触轮与工件的局部几何特征贴合。在曲率较小的局部,相邻刀位点的弧长加大,以保证加工效率。相反地,在曲率较大的局部,相邻刀位点的弧长较小,以保证加工精度。利用一系列平面与目标曲面相截,得到相应的截平面的轮廓曲线。对于任意一条轮廓线,优化相邻刀位点之间的弧长,在曲率较大的局部增加一个中间刀位点。本文提出了一种包含弧长优化和主曲率匹配的磨削路径生产方法,通过离线仿真验证了有效性,并利用该方法提高了曲面的磨削质量。该路径规划方法为生成光顺且精确的机器人曲面磨削路径提供了理论依据。

A Path Planning Method for Robotic Belt Surface Grinding

The flexible contact and machining with wide strip are two prominent advantages for the robotic belt grinding system, which can be widely used to improve the surface quality and machining efficiency while finishing the workpieces with sculptured surfaces. There lacks research on grinding path planning with the constraint of curvature. With complicated contact between the contact wheel and the workpiece, the grinding paths for robot can be obtained by the theory of contact kinematics. The grinding process must satisfy the universal demands of the belt grinding technologies, and the most important thing is to make the contact wheel conform to the local geometrical features on the contact area. For the local surfaces with small curvature, the curve length between the neighboring cutting locations becomes longer to ensure processing efficiency. Otherwise, for the local areas with large curvature, the curve length becomes shorter to ensure machining accuracy. A series of planes are created to intersect with the target surface to be ground, and the corresponding sectional profile curves are obtained. For each curve, the curve length between the neighboring cutting points is optimized by inserting a cutter location at the local area with large curvatures. A method of generating the grinding paths including curve length spacing optimization is set up. The validity is completely approved by the off-line simulation, and during the grinding experiments with the method, the quality of surface is improved. The path planning method provides a theoretical support for the smooth and accuracy path of robotic surface grinding.