Vibration table ultra-low frequency sine sweep signal amplitude recognition method based on sampling in variable sampling rate

Abstract

The invention provides a vibration table ultra-low frequency sine sweep signal amplitude recognition method based on sampling in a variable sampling rate. Firstly, vibration table vibration signals, those are, vibration table sweep signals are acquired and obtained through a vibration sensor arranged on the vibration table; then, the acquired vibration table sweep signals are subjected to anti-aliasing filtering through a low-pass filter to filter the high-frequency part; vibration table sweep signals at equal phase intervals are obtained through a variable sampling rate sampling method; and finally, a least square fitting amplitude recognition method is adopted to realize sweep signal amplitude recognition. The variable sampling rate sampling method is adopted to change time-varying sine sweep signals to standard sine signals, and the signals can be analyzed and processed conveniently; due to the least square fitting, the non-full period signal amplitude can be obtained; the real-time performance requirements of vibration control can be ensured; and due to the combination of the two, the problems of time varying and the non full period existing in ultra-low frequency sine sweep signal amplitude recognition are solved.

Description

technical field [0001] The invention relates to the field of vibration test control, in particular to a method and system for ultra-low frequency sine sweep signal filtering and amplitude identification. Background technique [0002] In the process of transportation, storage and use, the product sometimes encounters very low vibration frequencies, such as earthquakes, ship (ship) borne equipment, vehicle-mounted equipment, and its main fundamental frequency may be as low as below 1Hz. Therefore, relevant tests are required to test the dynamic characteristics and reliability level of the product, and the sine sweep vibration test is one of the basic types of environmental and reliability tests. [0003] At present, the electric vibration table is most used in the laboratory, and the low-frequency end of the domestic and foreign electric vibration table generally starts from 5-10 Hz. With the development of technology, it can already realize the low-frequency vibration of 1-2 ...

AI Technical Summary

Problems solved by technology

[0006] The present invention proposes a vibration table ultra-low frequency sine sweep signal amplitude recognition method based on variable sampling rate sampling, which replaces the traditional tracking filter, root mean square, peak value, and average value amplitude recognition methods, and can effectively solve the problem of ultra-low frequency sweep signals. The problem of low accuracy of amplitude recognition caused by time-varying frequency signal and small amount of data

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