基于曲面分层的增材制造是目前研究热点之一. 相比于平面路径规划，在曲率任意变化的复杂空间曲面上进行路径规划算法研究较少，尤其是等距路径规划算法. 提出了一种基于体素化和曲线积分思想的空间曲面等距路径规划算法，算法主要包括体素化模型、计算体素点到源曲线的测地距离、生成增材路径等步骤. 该算法精度可控，其精度主要由模型体素化密度决定；与扫描线法相比，从根本上避免了平移路径时由于局部和全局自相交生成的无效环，提高了计算效率. 最后，选取3种典型曲面，分别为由平面组成的简单曲面、圆柱曲面、B样条曲面，进行空间曲面等距路径规划，已验证算法的适用性，并在圆筒试件上进行曲面分层GMAW电弧增材验证试验. 结果表明，该算法可以满足电弧增材制造的精度要求.
The additive manufacturing based on curved layer is one of the hot spots in current research. Compared with plane path planning, the research of path planning algorithm on complex space surface with arbitrary curvature change is less, especially the equidistant path planning algorithm. In this paper, a path planning algorithm based on voxelization and curve integration is proposed. The precision of the algorithm is controlled and mainly depends on the voxelization density of the model. The algorithm mainly includes voxelization model, calculating the shortest distance from voxel point to source curve, generating additive path. Compared with the scanline method, the algorithm avoids the invalid loop generated by local and global self intersection when translating the path, and improves the computational efficiency. Finally, three typical curved surfaces are selected for curved surface equidistant path planning, including sample curved surface, cylindrical surface and B-spline surface, to prove the applicability of the algorithm. The verification test of curved surface layered GMAW arc additive is carried out on the cylinder specimen. Planning and experimental results show that the proposed algorithm has enough accuracy for GMAW arc additive.
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