二维不规则排样背景下的零件像素化表达算法

Pixelated expression algorithm of parts under background of two-dimensional irregular layout

针对目前主流的零件表达方式,当零件外形呈现出凹多边形特性且顶点数目较多时,冲突检测算法明显变慢的问题,提出了一种零件像素化表达方法,即在零件包围盒上布置多个方形微粒,然后,通过二维布尔变量数组存储微粒是否被占用的信息,提出了微粒"占用"的判断算法。算例1研究了像素图生成速度与微粒边长和零件外形的关系;算例2则研究了零件像素化程度与排样性能的关系,最后,给出了推荐的微粒边长。推荐微粒边长可令排样计算速度和排样效果取得最佳的平衡。同时,算例2还与商用排样软件SigmaNest进行了对比,实验结果表明,如果使用推荐的微粒边长,本文算法得到的材料利用率高于SigmaNest算法,且计算耗时只有后者的2.8%。

For the current mainstream expression way of parts,when the shape of part exhibits concave polygonal characteristics and the number of vertices is larger,the conflict detection algorithm is significantly slower.Based on the above issue,a pixelated expression method of part was proposed,which was to arrange multiple square particles on the part bounding box,and then based on the information that whether the particles were occupied which was stored by two-dimensional Boolean variable array,the judgment algorithm of particles being occupied was proposed.Furthermore,the relationships between the speed of pixel image generation and the side length of particles and the shape of part were studied by calculation example 1,and the relationship between the pixelization degree of part and the performance of layout was studied by calculation example 2.Finally,the recommended side length of particles was given,which made the best balance between the layout calculation speed and the layout effect.At the same time,the calculation example 2 was compared with the commercial layout software SigmaNest.The experimental results show that if the recommended side length of particles is used,the material utilization ratio of algorithm in this paper is higher than that of SigmaNest,and the calculation time is only 2.8%of the latter.