苏 春 黄 漪

东南大学机械工程学院，南京，211189

装配误差传递建模及其精度可靠性评估

苏 春 黄 漪

东南大学机械工程学院，南京，211189

研究了刚体零件的装配误差建模以及装配精度可靠性评估方法。将零件误差分成位置误差和方向误差，并采用误差矢量加以描述。综合考虑尺寸误差和形位误差，将装配过程误差分成零件内误差和配合面误差，给出主动配合面和被动配合面的定义。针对典型配合面类型，分析误差组成及其计算方法。采用位姿变换矩阵法建立装配误差模型，分析误差在零件内部以及配合面间的传递过程，计算装配总误差并据此确定装配误差的概率分布。给出装配精度可靠度的定义，通过仿真获得装配精度的可靠度指标。以某测量平台的装配过程为例，完成装配过程误差分析和装配精度可靠度评估，验证模型的有效性。

零件内误差；配合面误差；位姿变换矩阵；装配误差；装配精度可靠性

Abstract:The modeling of assembly errors and the precision reliability assessments for rigid parts was investigated. The part errors were divided into position errors and orientation errors, and described with part error vectors. Considering the differences between dimensional errors and geometrical errors, the assembly errors were classified into internal errors of parts and joint surface errors. The concepts of active joint surfaces and passive joint surfaces were proposed. The composition of the errors and their calculation methods were proposed according to typical types of joint surfaces. An assembly error model was developed through the approach of pose transformation matrix, after that the assembly error accumulations and propagations were analyzed, and the assembly errors were calculated. The probability distributions of assembly errors were determined on the basis of statistical analyses. The concept of precision reliability was proposed, and simulation approach was adopted to calculate the reliability, which provides basis for the evaluation of assembly precisions. Case study of a measuring platform was provided, the assembly errors and precision reliability were obtained, the effectiveness of the proposed models were verified.

Keywords:internal error of part; joint surface error; pose transformation matrix; assembly error; assembly precision reliability

0 引言

装配是机械产品研制的重要环节。装配精度不足会影响产品的预期功能，装配精度过剩又会增加生产成本,因此，开展装配误差源及其传递规律研究、分析装配精度可靠性，具有重要意义。

误差源分析是开展装配精度分析的前提。刘伟东等[1]研究了装配误差的传递机理，将装配误差分为几何位置偏差、形状偏差和装配位置偏差等。彭和平等[2]基于装配过程中的形位公差分析，建立了二维装配模型。文献[3]将误差源分为工件自身、定位固定装置、夹具的尺寸误差及形位公差等因素。……