Spindle system operational modal analysis method based on pulse excitation response signal cross-power spectrum function

Abstract

The invention relates to a spindle system operational modal analysis method based on a pulse excitation response signal cross-power spectrum function. The method comprises the following steps: 1) respectively selecting exciting points on a cutter shank of a spindle system and conducting pulse excitation on the spindle system at the selected exciting points by using a steel hammer; 2) acquiring response signals produced by a reference point and response points after pulse excitation; 3) conducting band-pass filtering on the acquired signals; 4) resolving a cross-power spectrum function between the reference point and the response points, and establishing a matrix equation formed by different sampling time data of the cross-power spectrum function; 5) solving a coefficient matrix by using the matrix equation to obtain system poles; 6) recognizing a modal shape and a modal participation factor matrix; 7) conducting modal assurance criterion matrix value calculation, and when the modal assurance criterion matrix value is within a preset reasonable range, obtaining the modal parameters of the spindle system. The spindle system operational modal analysis method based on the pulse excitation response signal cross-power spectrum function has the advantages that quick calculation can be realized, the accuracy is high, the error control effect is better, the testing strength and time can be reduced and the testing efficiency is greatly improved.

Description

technical field

[0001] The invention relates to the technical field of operation mode analysis, in particular to an analysis method for the operation mode of a spindle system. Background technique

[0002] The dynamic characteristics of the spindle system have a direct impact on the machining accuracy and cutting efficiency of the machine tool. Accurately mastering the modal parameters of the spindle system including tool-toolholder-spindle is an important basis for stability prediction and processing parameter optimization. Usually, the excitation is applied at the tip of the tool and the response is picked up to obtain the frequency response function of the tip of the tool, and then the modal parameters of the system are obtained by the experimental modal analysis.

[0003] However, due to the constant replacement of the tool, when the structure of the spindle system changes, the test needs to be re-tested, which increases the test time. The operational modal analysis met...

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