中文摘要：

借鉴CAD模型的自由曲面轮廓度误差评定模型,给出STL模型;把空间点到STL模型的有向距离转化为点到自由曲面的距离的计算方法,并结合带有收缩因子的粒子群算法对自由曲面的轮廓度误差进行评定。该模型成功解决了测量仪检测自由曲面时存在的设计坐标系与检测坐标系不重合的问题。主要工作是用粒子群算法解决被测曲面和设计曲面之间的定位问题,同时简化计算了空间点到STL模型的距离。在搜索空间点所对应三角面片的过程中,兼顾就近原则确定对应顶点,从而提高了搜索效率;最后运用仿真实验验证了算法的可行性。采用该方法能够有效地评定已知CAD模型的自由曲面的轮廓度误差。

英文摘要：

Learning from the freeform surface profile error evaluation of CAD model, STL model was given~ The distance from spatial points to STL model was transformedas that from those points to freeform surface. And particle swarm optimization with a constriction factor was used to evaluate the profile error offreeform surfaces. This model solved the un-repetition between design coordinate system and measurementcoordinate syste The main work was to take the particle swarm optimization to realize the localization between measured surface and design surface ,and,simplified the calculation of the distance fromspatial points to STL model. In the process of hunting the triangular patch corresponding to the spatial point, a method that acorresponding vertex could be found based on the nearest distance was presented, which improved search efficiency. Finally a simulation experiment was performed to demonstrate the validity of the approach. It is indicated that the approach could evaluate the profile errors offreeform surfaces known by CAD model effectively.