Abstract: In order to solve the problem of porous structure design of tissue engineering bone scaffold,a bone scaffold design method based on voxel and Triple Cycle Minimal Surfaces (TPMS) was proposed.Firstly,TPMS expressed by implicit function was used as the basic pore unit for constructing microporous structure.By defining the distance function and Log-Sigmoid function,different structures with TPMS pore elements were constructed.Then,the voxelization algorithm of inverse geometric intersection was used to divide the triangular mesh model into spatial units to determine the target assembly area.Then,through the coordinate transformation of the shape function,the pore unit was mapped into the space unit to construct the spatial domain porous structure.Finally,a Boolean operation was used to obtain a bone scaffold model with porous structure.Experimental results showed that the proposed design method could construct a porous model with controlled pore structure to meet the design requirements of tissue engineering bone scaffold.

Key words: porous structure, bone scaffold, triple cycle minimal surfaces, voxelization

摘要： 为解决组织工程骨支架多孔结构设计问题,提出一种基于体素和三周期极小曲面的骨支架设计方法。采用隐函数表达的三周期极小曲面作为构建微观多孔结构的基础孔隙单元,通过定义距离函数及Log-Sigmoid函数的方法,构建不同结构的三周期极小曲面孔隙单元;采用逆向几何求交体的体素化算法,对三角网格模型进行空间单元划分,进而确定目标装配区域;再通过形函数坐标变换,将孔隙单元映射到空间单元中,从而构建空间域多孔结构;最后采用布尔运算得到具有多孔结构的支架模型。实例结果表明,所提设计方法能构建孔隙结构可控的多孔模型,从而为组织工程骨支架设计提供一种可行的方法。

关键词: 多孔结构, 骨支架, 三周期极小曲面, 体素化