Abstract: To meet the data exchanges requirement of models between five-axis machining simulation system and Computer Aided Design (CAD) and to provide a high efficiency complex initial rough modeling method,a voxelization method oriented to STL model was proposed.The octree model was improved to express the real space by using dual-level structure of external hierarchical tree and internal linear,and the coding calculation rule of this structure's octree model was given.The triangular facets of STL model was taken as the voxelization object to establish the mapping relationships from triangular facets and interior space of STL solid to voxel nodes by coding rules,which could realize the quick locating of voxels.The example showed that the proposed method could produce an accurate 26-adjacent voxel model,and had better time and space performances than traditional octree model.

Key words: virtual machining simulation, data exchange, STL model, octree, voxelization

摘要： 为满足五轴加工仿真系统与CAD系统的模型数据交换需求,提供高效的复杂初始毛坯建模方式,提出一种面向STL模型的体素化方法。改进了传统的八叉树模型,采用外部层次树型和内部线性的双层次结构表达实体空间,并给出了该双层次八叉树模型的编码计算规则。以STL模型三角面片为体素化对象,通过编码规则建立三角面片和STL实体内部空间与体素节点的映射关系,实现表面和内部体素的快速定位。通过实例证明了算法能够保证生成体素模型的26-邻接性,实验结果表明,与传统的八叉树模型相比,该算法具有更好的时间和空间性能。

关键词: 虚拟加工仿真, 数据交换, STL模型, 八叉树, 体素化