Boyd Steven K, Müller Ralph
Institute for Biomedical Engineering, Swiss Federal Institute of Technology (ETH), University Zürich, Zürich, Switzerland.
J Biomech. 2006;39(7):1287-95. doi: 10.1016/j.jbiomech.2005.03.006.
Finite element (FE) modelling based on data from three-dimensional high-resolution computed tomography (CT) imaging systems provides a non-invasive method to assess structural mechanics. Automated mesh generation from these voxel based image data can be achieved by direct conversion to hexahedron elements, however these model representations have jagged edges. This paper proposes an automated method to generate smoothed FE meshes from voxel-based image data. Mesh fairing processes are utilized that allow constraints that control the smoothing process, and are computationally efficient. Surfaces of the mesh on the exterior, as well as interfaces between two tissues, can be smoothed by varying fairing parameters and constraint criteria. The method was tested on a variety of real and simulated three-dimensional data sets, resulting in both hexahedron and tetrahedron meshes. It was shown that the fairing process is linearly related to the number of smoothing iterations, and that peak stresses are reduced in FE simulations of the smoothed models. Although developed for micro-CT data sets, this fast and reliable mesh smoothing method could be applied to any three-dimensional image data where node and element connectivity have been defined.
基于三维高分辨率计算机断层扫描（CT）成像系统数据的有限元（FE）建模提供了一种评估结构力学的非侵入性方法。通过直接转换为六面体单元，可以从这些基于体素的图像数据实现自动网格生成，然而这些模型表示具有锯齿状边缘。本文提出了一种从基于体素的图像数据生成平滑有限元网格的自动化方法。利用了网格光顺处理，该处理允许控制平滑过程的约束，并且计算效率高。通过改变光顺参数和约束标准，可以对网格的外部表面以及两个组织之间的界面进行平滑处理。该方法在各种真实和模拟的三维数据集上进行了测试，生成了六面体和四面体网格。结果表明，光顺过程与平滑迭代次数呈线性关系，并且在平滑模型的有限元模拟中峰值应力降低。尽管该方法是为微CT数据集开发的，但这种快速可靠的网格平滑方法可应用于已定义节点和单元连通性的任何三维图像数据。
