Research On Evaluation Algorithm And Visualization Of Cylindericity Error

Extremely sophisticated manufacturing technology included High-grade,Precision and Advanced(industrial products)is inevitable trend of manufacturing.Ultra precision machining technology is an Engineering Science and technology in pursuit of constantly improving the machining accuracy as the goal,is also a typical kind of extreme manufacturing technology.In the background of "Made in China 2025",ultra precision machining technology is one of the important signs to measure the manufacturing level of our country,which is also the foundation of national high-tech and strategic emerging industries.The processing level of the parts is one of the most basic technical level at the aspect of ultra precision machining technology,which include the theory and algorithm of Form-Position Error evaluation is a very important technical aspect.As one of the most complex detection methods in the evaluation of Form-Position Error,the cylindricity evaluation theory is not yet refined,so this paper makes the following research on cylindricity error evaluation algorithm:(1)Introduce the background of the cylindricity error on digital detection and evaluation research,list of inspection tools and evaluation methods currently used.Introduce the recent internal and aboard research to the problem and the improved algorithm what the related researcher have done.(2)Aimming at the initial baseline of mesh successive approximation algorithm mostly is generation by fitting line of measuring points with least square method,it has the defect that can not be maximized close to the ideal axis.Combined with the evaluation of cylindricity error related literature and referencing roundness,straightness evaluation criteria,starting from the optimization baseline and the grid point,using Genetic Algorithm’s evolutionary principle,this paper proposed a new mesh successive approximation algorithm.(3)Combined with the cylindrical geometry theory and Genetic Algorithm,a high accuracy and high efficiency evaluation algorithm is proposed.In order to getting a stronger adaptability to the precision of different workpiece,this paper establish the variable coefficient search domain of optimized parameters;By homogenizing population initial value with real encoding and combined with a new generation of Genetic Algorithm operator,this complex algorithm enhances the stability.Comparing the results of multiple sets of data by MATLAB prove the practicability of the algorithm.(4)Derivation calculation method of 2D inner convex hull and 3D convex hull based on the calculation method of 2D convex hull referring to the basis of the computational theory.In this paper,the feasibility of solving cylindrical contour with inner and outer convex shells is analyzed,cylindrical inner convex hull algorithm is proposed for measuring the inner contour of cylinder.Combined with the 3D convex hull algorithm,this paper get the total contour of cylinder.The corresponding contour points and the contour map are also given.(5)This paper establish many evaluation model based on Genetic Algorithm,Writing algorithm program for the convenience of visualization of cylindricity error evaluation,which include the iterative graph of the optimal solution based on Genetic Algorithm,the point contact graph based on the accuracy and so on.