Abstract: The batch layout of various types of parts in additive manufacturing has problems such as high printing time cost and low utilization of workbench space,and the impact of the height of the parts needs to be considered.The batch layout problem includes two sub-problems,the part placement strategy on the workbench and the allocation of molding batches.The placement strategies involve the forming direction selection,the part collision detection,and the positioning strategies.Based on the established forming direction criterion,the polygons were used to represent the projected contour of parts.Based on no-fit polygon,an improved orbital sliding approach was proposed to determine the collision-free emission range of polygonal parts with three categories.A new bottom-left positioning strategy to place parts was proposed,which integrated an improved constructive approach and fit degree.A strategy of the used maximum area in a worktable was proposed to achieve the part molding batch allocation.On the basis of above research,a batch layout algorithm based on the optimal foraging algorithm was proposed.The algorithm used the double coding to express the part placement order and the rotation angle,and realized batch layout optimization by taking minimum completion time as the objective.The proposed algorithm was compared with three comparison algorithms based on some library parts,and the results showed that the proposed method could effectively improve the space utilization of additive manufacturing and shorten the completion time.

Key words: additive manufacturing, batch layout, optimal foraging algorithm, three-dimensional nesting

摘要： 增材制造中多种类零件分批排样存在打印时间成本高和工作台空间利用率低等问题,且需考虑零件高度的影响。分批排样问题包括零件在工作台上放置策略和成型批次分配两个子问题。放置策略涉及成型方向选择、零件碰撞检测和定位策略。基于建立的成型方向准则,利用多边形表示零件投影轮廓,提出基于临界多边形的改进移动碰撞法以确定3种不同形态多边形零件的免碰撞排放范围,提出新的左下定位策略放置零件,新定位策略融合了改进的建设性方法和契合度;提出单机台面积占用最大化策略实现零件成型批次分配。基于上述研究,提出基于最优觅食算法的分批排样算法,算法采用双重编码表达零件放置顺序和旋转角度,以最小化完工时间为目标实现优化分批排样。以案例库零件为对象,与3种对比算法比较,表明所提方法的方案能有效提高增材制造的空间利用率和缩短完工时间。

关键词: 增材制造, 分批排样, 最优觅食算法, 三维排样