The Complex Shape Of The Contour Geometry Of The Error Evaluation Study

Form error makes great effect to the quality of piece parts, it is difficult to evaluate the error of complex curve and surface, the research on the form error evaluation of the complex curve and surface has important theory significance and economic value. In this article, the form error is studied based on matlab and calculating example is presented. The main research is as follows.1,The mathematical model include straightness error, flatness error, Circularity error, cylindricity error, sphere error, taper error are studied, the optimization algorithms based on matlab is used to calculate form error, the error evaluation is presented in detail in this paper.2,According to minimal zone law, the mathematical model of complex curve profile error evaluation is created, the mathematical model of theoretical curve is constructed with NURBS by interpolating design points, the subdivision approximating algorithm is taken for fast calculating the minimum distance between measure points and theoretical profile curve, the position between the measure points and the theoretical profile is matched through coordinate transform to avoid the evaluation error derived from position error, the error evaluation of line profile is presented in detail in this paper.3,According to minimal zone law, the mathematical model of complex surface profile error evaluation is created, The mathematical model of theoretical surface is constructed with NURBS by interpolating design points, the subdivision approximating algorithm is taken for fast calculating the minimum distance between measure points and theoretical surface, the position between the measure points and the theoretical profile is matched through coordinate transform to avoid the evaluation error derived from position error,the BFGS algorithm is taken for calculating nonlinear optimization. The error evaluation of surface profile is presented in detail in this paper.4,A new error evaluation software based on the optimization toolboxes of MATLAB is presented to validate the method of form evaluation. The experiment results show the proposed method can rapidly acquire a better result.