面向机械臂3D打印的曲面分区算法

Surface Partitioning Algorithm for Robotic Arm 3D Printing

多自由度机械臂3D打印能够突破传统平面分层熔融沉积3D打印工艺单一模型生长方向的限制,支持多方向打印。曲面分层和分区规划是机械臂打印的前提。对于具有多支柱结构或曲面变化率较大的模型经过曲面分层后,会呈现出多岛屿的曲面结构特征。传统的基于空间与平面映射关联的分区方法及基于曲面曲率特性的分区方法存在点面信息丢失、区域关系无法准确构建、子区域数量过多、区域划分不合理等问题。针对这些问题,提出基于曲面分层的复杂多岛屿分区方法。通过遍历每个曲面层信息,判断需要分区的曲面层;采用广度优先搜索算法提取同一封闭区域内的点面信息以及轮廓信息;依据原曲面层点面信息的关联将新存储的面片信息进行更新组合成新的曲面完成区域划分。最终,对具有多支柱结构和外表面凹凸变化较大的两种模型进行分区,路径规划的仿真及机械臂3D打印实验证明了该分区方法的可行性。

The multi-degree-of-freedom robotic arm 3D printing can break through the limitation of the growth direction of a sin⁃gle model in the traditional plane layered fused deposition 3D printing process and support multi-directional printing.Surface layering and partitioning planning are the prerequisites for robotic arm printing.For the model with multi-pillar structure or large surface change rate,after surface layering,it will show surface structure features with multiple islands.The traditional partitioning method based on the association of space and plane mapping and the partitioning method based on surface curvature characteristics have problems such as loss of point and surface information,inability to accurately construct regional relationships,too many sub-regions and unreasonable re⁃gional division.Aiming at these problems,a complex multiple islands partitioning method based on surface layering was proposed.By traversing the information of each surface layer,the surface layer needed to be partitioned was judged;the breadth-first search algorithm was used to extract the point-surface information and contour information in the same closed area;according to the association of the point-surface information of the original surface layer,the newly stored patch information was updated and combined into a new surface to complete the area division.Finally,the two models with multi-pillar structure and large variation of outer surface were partitioned,and the feasibility of the partition method was proved by the simulation of path planning and the 3D printing experiment of the robotic arm.