Abstract: Aiming at the inspection and evaluation problem of aero-engine blade surface with unuiform distribution of tolerance,a new registration method of blade model based on constraint of profile tolerance was developed.According to the definition of contour tolerance,a generation method for blade contour tolerance model based on middle camber line was provided.A mathematic model for registration of blade section profile based on contour tolerance was built,and a solution process to the tolerance constrained registration of blade section profile based on Nelder-Mead simplex method was given.The validity of proposed method was verified by using simmulation data,actual CMM data and theoretic model of blade.The experiment results showed that Nelder-Mead simplex method could be used to resolve the problem of profile tolerence constrained blade model alignment.Campared with the best-fit method,the disscussed method could reduce the number of points outside the profile tolerance zone,which could be adopted as additional reference for blade inspection and evaluation.

Key words: aero-engine blade, tolerance zone, model registration, constraint condition

摘要： 针对公差非均匀分布的发动机叶片叶型检测评估问题,提出一种基于轮廓度公差约束的叶片模型配准方法。根据叶片轮廓度公差定义,给出一种基于中弧线的叶片轮廓度公差模型生成方法。建立了轮廓度公差约束的叶型截面配准数学模型,并给出了基于Nelder-Mead单纯形法的叶型截面带约束配准求解过程。采用仿真数据及实际叶片的三坐标测量数据与理论模型,对所讨论的模型配准方法进行了验证。结果表明,Nelder-Mead单纯型法可用于薄壁叶片模型的带约束配准求解;与最佳贴合配准相比,公差带约束配准方法可减少测量数据点集的超差点数目,为叶片检测评估提供更多参考。

关键词: 发动机叶片, 公差带, 模型配准, 约束条件