Machined part surface vibration line defect detection method

Abstract

The invention discloses a machined part surface chatter mark defect detection method which comprises the following steps: measuring acceleration response signals of a cutter along the horizontal and vertical directions of a machine tool in the current machining process of a part, filtering cutter-pass harmonic components in the acceleration response signals, extracting wavelet entropy characteristics reflecting machining instability intensity in the acceleration response signals, and calculating the chatter mark defect of the machined part, recording the wavelet entropy characteristics as a vibration characteristic; inputting the vibration characteristics into a pre-trained flutter detection model, and judging the flutter state of a current weak-rigidity machining system for machining thepart; and if the part is in the flutter state, the current machining surface of the part has the chatter mark defect. After each part is machined, according to the accuracy of the current flutter detection model, on the basis of an existing flutter detection model, an incremental learning mode is adopted, continuously-accumulated actual measurement vibration information is utilized, some information which can have adverse effects on judgment precision is eliminated step by step, and therefore the accuracy of the flutter detection model is improved, and the accuracy of the flutter detection model is improved. And the detection precision of the machined surface chatter mark defects is high.

Description

technical field [0001] The invention belongs to the field of processing defect detection, and more specifically relates to a method for detecting vibration marks on the surface of a processed part. Background technique [0002] The surface vibration defects of parts determine the service performance and fatigue life of parts. Surface chatter marks are imprints engraved on the surface of the part by the vibration displacement of the cutter teeth during the machining process. Chatter marks are often caused by flutter in machining vibration, and the characteristics of chatter and chatter marks show a high similarity in frequency distribution. Therefore, the flutter information similar to the characteristics of the chattering defect can be extracted from the processing vibration signal as the basis for judging whether there is a chattering defect. [0003] During the machining process, the accurate judgment of machining chatter provides conditions for timely avoiding the deter...

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Problems solved by technology

[0004] Aiming at the above defects or improvement needs of the prior art, the present invention provides a method for detecting chattering defects on the machined surface, the purpose of which is to solve the problem of chatter detection models occurring in the prior art due to the removal of workpiece material and tool wear during the machining process. Parameter drift, which leads to the technical problem of low detection accuracy of surface vibration defects

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