Abstract: Aiming at the problems of long planning time, low efficiency and long path distances in the process of traditional contact on-line measurement path planning of complex curved workpiece,a contact on-line measurement path planning method of complex curved workpiece was proposed. Firstly, the dynamic collision detection between workpiece and probe was converted into static collision detection by discrete method, and according to the different collision accuracy requirements, the hierarchical collision detection was carried out based on the combination of rough detection and fine detection. Then, to simplify static collision detection, the grid space range was determined based on the AABB (axis-aligned bounding box) bounding box of the workpiece to be measured, considering only the direct contact of the workpiece to the worktable. Lastly, the pheromone of ant colony algorithm was initialized by the 3D path segment which was generated by the A* algorithm. Through the heuristic information function and the probability selection function of the improved ant colony algorithm, the node search principle and strategies to avoid dead cycles or traps was designed, the initial measuring path segment of collision was re-planned to realize the collision avoidance and the optimization measurement path.The research results show that,comparing with the project of planning the measurement sequence after forming the path matrix, the project of collision avoidance after forming the initial path can save 85% of the path planning time; under the same initial path, the path generated by the improved ant colony algorithm is shorter; the measurement path planning method can plan a better measurement path in a short time.

Key words: complex curved; online measurement; path planning; ant colony algorithm

QI Hong-fang, GUO Run-qi. Contact online measurement path planning for complex curved workpiece［J］.Journal of Mechanical & Electrical Engineering, 2021,38(11):1472-1478.