Method for analyzing sensitivity of geometric errors of dual-rotation axes of five-axis CNC machine tool

Abstract

The invention proposes a method for analyzing sensitivity of geometric errors of dual-rotation axes of a five-axis CNC machine tool, and the method comprises the following steps of firstly constructing a mathematical model of geometric errors of the dual-rotation axes based on a multi-body system theory and a homogeneous transformation matrix; performing error parameter sampling by using a Monte Carlo method, and analyzing the sensitivity of the geometric errors of the dual-rotation axes of the CNC machine tool; finally performing sensitivity analysis on the error parameters based on the positions of the specific rotation angles of the dual-rotation axes, and calculating the first-order sensitivity and global sensitivity of each geometric error of the dual-rotation axes at this position bysetting the positions of five groups of specific rotation angles, wherein the Sobol sensitivity analysis method can be used to identify the key geometric error among the 20 geometric errors of the dual-rotation axes, and complete the identification of the geometric errors of the dual-rotation axes of the five-axis CNC machine tool. The method has the advantages of simple detection steps, convenient measurement and high identification accuracy.

Description

technical field [0001] The invention belongs to the technical field of error detection of numerical control machine tools, and in particular relates to a method for identifying geometric errors of dual rotation axes of five-axis numerical control machine tools based on sensitivity analysis. [0002] technical background [0003] Compared with three-axis CNC machine tools, five-axis CNC machine tools have the ability to process complex parts. The reason is that five-axis CNC machine tools have added two rotation axes compared with three-axis CNC machine tools. When the five-axis CNC machine tool is used for machining, the generated tool path has greater flexibility than that of the traditional three-axis machine tool. However, the rotary axis introduces its own error elements during machining, and the geometric error has a great influence on the total error, which affects the machining accuracy of the machine tool to a large extent. [0004] Geometric errors are generally con...

AI Technical Summary

Problems solved by technology

The geometric errors of the rotary axes are coupled with each other, and it is difficult to quickly identify the geometric errors of the dual rotary axes by the general method. Therefore, it is very important to propose a method that can quickly and easily identify the geometric errors of the dual rotary axes of the five-axis CNC machine tool to improve the machining accuracy of the machine tool.

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