关键词: 三维排样, 不规则排样, 混合表达, 全姿态, 构造算法

Abstract: To solve the bottleneck problems in the three-dimensional irregular packing problems,two improved methods were proposed.First,the vector graphics were hybridized with bitmaps to describe the 3D irregular parts.The parts were described in form of vector graphics during the primary procedure of packing,and then represented by the cube-shaped particles before seeking optimal packing attitude.To eliminate the gaps between the parts and to export the accurate packing layout,the parts were restored again with vector graphics.Second,the concept of all-attitude in aerospace field was introduced.Multiple surface points were evenly arranged on the sphere through the longitudinal and latitudinal lines.Thus,multiple axis of rotation could be determined by taking the center of sphere as the starting point and the surface point as the ending point.In this way,the part could get more rotating shafts than the traditional method,thus greatly improving the optimization search space of the packing attitude.Numerical examples proved that the proposed algorithm had the advantages of fast execution speed and good layout performance.

Key words: three-dimensional packing, irregular packing, hybrid representation, all-attitude, constructive algorithm