Abstract
Blend features usually exist in the machining of complex multi-cavity parts; however, the ideal linear boundary of the cavity is shown as an arc curve at actual corner machining, which affects the accuracy of a robot's tool feed position. Focused on this problem, this article presents an automatic tool path planning approach based on blend feature simplification. By analyzing the geometric elements of blend feature, a line segment is constructed to obtain the machining boundary, while the robot tool feed position is accurately measured. On this basis, the coordinates of a robot tool feed position are assigned to the machining element, which can be used to calculate the spatial distance between different cavities. Then, an improved genetic algorithm is applied to improve the optimization of the tool path. The automatic decision of the corresponding work steps is realized by merging and sorting the machining elements. Finally, a corresponding prototype system is presented, with the correctness and validity of the proposed approach being examined, using aircraft structural part machining as an illustrative example.