Tuning fork resonance frequency quick measuring method based on virtual instrument

Abstract

The invention belongs to the technical field of test and measurement. A turning fork resonance frequency quick measuring method based on a virtual instrument is characterized in that the tuning fork starts oscillation with colored-noise signal excitation, collects signals of an output end of the tuning fork, and then carries out filtration and spectral analysis on the collected signals. The resonance frequency of the tuning fork can be quickly measured by spectral analysis. A measurement system comprises a general-purpose computer, intelligent measuring software, and a special sound card. Theintelligent measuring software generates the colored-noise signals with appointed bandwidth and value of amplitude by driving the special sound card; the colored-noise signals are used as the excitation signals of the input end of the tuning fork; and then the signals of the output end of the tuning fork is obtained by the collection of the special sound card. By the power analysis, the frequencywhich a spectrum peak corresponds to is the resonance frequency of the tuning fork. The method is based on the general purpose computer, uses the sound card as the data acquisition card, and utilizesa LabVIEW virtual instrument platform technology to compile the intelligent measuring software.

Description

technical field [0001] The invention belongs to the technical field of test and measurement, and relates to a method for quickly measuring the resonant frequency of a tuning fork through digital signal processing technology based on virtual instrument technology. Background technique [0002] The tuning fork can be regarded as a two-port network. When it is being measured, it is excited by a sine wave signal to vibrate, and the amplitude of the tuning fork changes with the frequency of the exciting sine wave. The tuning fork filter has the following advantages: simple structure, small size, low temperature coefficient of frequency, large quality factor, narrow passband, low insertion loss, and long life. Therefore, the tuning fork filter is currently widely used in the material detection switch system in the industrial field. [0003] The tuning fork filter needs to be combined with a closed-loop system to work properly. The design of the closed-loop system depends on its o...

AI Technical Summary

Problems solved by technology

However, for mechanical filters such as tuning forks, the start-up time is relatively long. When the frequency band involved is wide and there are many frequency points, the measurement time of this method is relatively long and the work efficiency is relatively low.

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