Online identification method for numerical control machining center based on vibration signals

Abstract

The invention belongs to the field of online flutter identification in the cutting process of a numerical control machining center, and particularly discloses an online flutter identification method for a numerical control machining center based on a vibration signal. The method comprises: collecting spindle vibration signals generated when a numerical control machining center conducts cutting machining, and preprocessing the vibration signal; constructing a multi-scale permutation entropy and a multi-scale power spectrum entropy of the preprocessed signal; splicing the multi-scale permutationentropy and the multi-scale power spectrum entropy to serve as feature vectors to be input into a constructed gradient boosting tree model; and performing iterative training on the vibration signal to obtain an optimal gradient boosting tree model, preprocessing the main shaft vibration signal in the machining process , and then inputting the preprocessed main shaft vibration signal into the optimal gradient boosting tree model, so that on-line identification of flutter of the numerical control machining center is achieved. According to the method, the chatter sensitivity characteristics of the machine tool can be extracted, whether the numerical control machining center chatters or not and the chatter severity can be identified, and the method has the advantages of being high in monitoring real-time performance, high in identification accuracy, good in generalization ability and the like.

Description

technical field [0001] The invention belongs to the technical field of monitoring the machining process of a numerical control machining center, and more particularly relates to an online identification method for flutter of a numerical control machining center based on vibration signals. Background technique [0002] Flutter is a self-excited vibration that is unstable, chaotic, and abnormal. On-line chatter identification of CNC machining center means that during the process of machining workpieces by CNC machining center, computers or other computing equipment can judge and identify whether chatter occurs in CNC machining center by detecting the changes of various types of sensor signals. The chatter identification process of CNC machining center is essentially a pattern recognition process. A complete online chatter identification system consists of the research object (NC machining center), processing conditions, sensor network, sequential signal processing, sensitive f...

AI Technical Summary

Problems solved by technology

[0004] After years of development, the chatter monitoring technology of CNC machining centers has made some progress in breadth and depth, but the current monitoring time and identification accuracy have not yet met the actual monitoring requirements, and its scope of application is limited, far from meeting the requirements of automation and intelligence. , still has certain limitations in practical application, such as insufficient identification accuracy, poor real-time monitoring, and inability to deal with complex processing scenarios and processing conditions.

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