基于多信息体素空间划分的高效自由曲面分层算法

An Efficient Free-form Surface Layering Algorithm Based on Multi-information Voxel Space Division

随着多自由度增材制造技术的发展,直接基于曲面的分层处理和路径规划方法被广泛研究。针对目前曲面分层算法通用性不强、效率低下等问题,提出基于多信息体素空间划分的高效鲁棒的自由曲面分层算法。通过将三角面片表面体素化,快速筛选出相交三角面片,算法时间复杂度由传统算法的平方复杂度降低为线性复杂度,解决了以往曲面分层算法难以处理大尺寸复杂模型的问题。根据三角网格邻接边的拓扑连续性避免同一轮廓环交点在不同求交条件下的重复计算,解决交点重复求交过程因为浮点数计算误差导致的点扩散问题,获取正确曲面轮廓交线环。最后对交线环内部的曲面进行三角剖分,获取曲面内部信息,得到曲面分层结果。测试了不同模型的圆柱面、球面、自由曲面等类型的曲面分层处理以及算法运行时间,验证了本算法的高效性和正确性。在6轴KUKA机器人和2轴变位机组合装备上对螺旋桨模型进行加工试验,证明了本算法的实用性。

With the development of more degree-of-freedom additive manufacturing technology, layered processing and path planning methods directly based on curved surfaces have been extensively studied. Aiming at the current problems such as low generality and low efficiency of the current surface layering algorithm, an efficient and robust free-form surface layering algorithm based on multi-information voxel space division is proposed. This algorithm quickly screens out the intersecting triangles by voxelizing triangular surfaces. The time complexity of the algorithm is reduced from the square complexity of the traditional algorithm to the linear complexity, which solves the problem that the previous surface slicing algorithm is difficult to handle large-scale complex models. According to the topological continuity of the adjacent edges of the triangle mesh, the repeated calculation of the intersection of the same contour loop under different intersection conditions is avoided. the point diffusion problem caused by the float point calculation error in the repeated intersection process of the intersection is solved, and the correct surface contour intersection loop is obtained. Finally, the inner surface of the intersection loop is triangulated to obtain the inner information of the surface, and obtain the surface layering result. The layered processing of cylindrical, spherical, and free-form surfaces of different models and the running time of the algorithm are tested to verify the efficiency and correctness of the algorithm. Processing experiments on the propeller model on the combined equipment of a 6-axis KUKA robot and a 2-axis positioner proves the practicability of the algorithm.