中文摘要：

零件表面由多个精度存在差异的特征组成,在模型配准时若不考虑精度的影响,则低精度部位的数据会使配准位姿偏离,造成配准结果不准确。为解决此问题,提出一种考虑特征区域精度差异的模型依次配准方法：先用高精度特征区域进行配准,该次配准确定模型变换空间中的一组标准正交基并约束了一些配准主方向;然后用低精度特征来配准,通过将配准变换向正交基上投影和分量置零的方法,使其不影响已有的高精度区域形成的配准约束。该方法使高精度区域有高的配准准确度,低精度区域的配准准确度低,更符合工程实际。通过对立方体仿真模型和整体叶轮工件的模型配准试验,验证了算法的有效性。

英文摘要：

The shape of a mechanical part is composed of a number of specific feature regions, each with their own precision level. If the shape registration between the scanned data and the CAD model is performed when ignoring the precision difference, an inaccurate alignment result will be produced due to the deviation of low fidelity regions. A new registration method taking into consideration of the region precision is proposed. The procedure is divided into several region-to-region matching steps. The regions with high precision are matched. This matching transformation brings a set of standard orthogonal bases for the transformation space, and at the same time it gives registration constraints on some principal directions. The low precision regions are used to do a new matching. By projecting the new transformation on the previous standard orthogonal bases and setting some terms to zero, the model transformation is restricted and has no movement on the principal directions determined by the high precision regions. Our method produces high matching accuracy on high precision regions and low matching accuracy on low precision regions, which is suitable for practical utility in engineering. The experiments on a simulated cube and a real impeller are presented.