基于几何配准的三维模型几何比对方法研究

针对设计师在进行协同建模时无法快速查看模型变更信息的问题，提出了快速比 对两个模型几何差异的方法。首先，通过等步长采点获取两个模型的点云数据；然后，利用主 元分析法计算两个点云的特征向量从而获取点云的参考坐标系，推导两个点云参考坐标系的坐 标变换，将两个点云调整到一致，即可实现点云的初始配准；最后，利用最近点迭代法对两个 点云进行精确配准，记录配准后两个点云中的非重叠区域，可获取两个点云的几何差异区域。 测试结果表明该方法可以有效识别两个模型的几何差异。

Research on Geometric Comparison of 3D Models#br# Based on Geometric Registration

In order to help designers to check model changes quickly in a collaborative design, this paper focuses on how to rapidly compare geometric differences between two 3D models. First, the equidistant point clouds of two models are computed, and then a reference coordinate system of each point cloud is obtained by using the principal component analysis method. A transformation is then found to match the two point clouds to achieve an initial registration. Finally, the ICP (iterative closest point) method is used to realize accurate registration for the two point clouds. By computing the non-overlapping domain after the exact registration, we obtain the geometric differences between the two point clouds. The numerical example shows that the proposed method can effectively recognize the geometric differences of two 3D models.