A method of sensitivity analysis and precision prediction for geometric errors of five-axis machine tools based on multi-body system theory

Abstract

In order to ensure the mechanical performance and machining accuracy of the machine tool, the problem of mutual deviations of the machine tool moving parts in the machining process, which cause machining errors and subsequent accuracy prediction difficulties, is solved.Firstly, the structure and motion mechanism of the machine tool are analysed, and a static accuracy model of the machine tool machining posture relationship is established using multi-body system theory and coordinate transformation, and the measured deviation values are fitted and solved according to the formula, and the geometric error law affecting machining accuracy and the distribution of machining point error values in the machine tool motion space are explored. Then the response surface method is used to simplify the solution. Finally, the blade is selected as the machined part and the machining trajectory is extracted for experiments to obtain the error distribution range of the machining surface of the blade.The final experimental results surface, along the Z-directional component and the integrated average compensation rate reached 42.6% and 89.6% respectively, verifying the effectiveness of the method in this paper.

Unified framework for geometric error compensation and shape-adaptive scanning in five-axis metrology systems

“…In the realm of sensitivity analysis for geometric errors, two principal methodologies prevail: local sensitivity analysis (LSA) and global sensitivity analysis (GSA). LSA employs techniques such as partial derivatives [68][69][70] to scrutinize the model's output changes in response to minor variations in input parameters. Its primary aim is to evaluate the gradient of the output function at specific input values.…”