Method and system for measuring micro-amplitude vibration of thin-walled parts based on motion amplification optical flow tracking

Abstract

The invention discloses a method and system for measuring the micro-amplitude vibration of thin-walled parts based on motion amplification optical flow tracking, and relates to the technical field of micro-amplitude vibration measurement of thin-walled parts, mainly obtaining the target vibration frequency through brightness changes; Gray-scale image sequence, amplifying the vibration amplitude; using the optical flow tracking algorithm to process the amplified video, extracting the vibration signal of the target corner point in pixels, and compensating for the attenuation; establishing a measurement mathematical model and converting it Vibration signal for real units. The invention combines the phase Euler amplification method and the optical flow tracking method, effectively solves the problem that the micro-amplitude vibration of thin-walled parts cannot be measured, and has the advantages of convenient operation, high spatial resolution, non-contact and visualized micro-vibration.

Description

technical field [0001] The invention relates to the technical field of micro-amplitude vibration measurement of thin-walled parts, in particular to a method and system for measuring micro-amplitude vibration of thin-walled parts based on motion amplification optical flow tracking. Background technique [0002] The measurement and research of tiny vibration signals are of great significance in both military and civilian applications. This kind of vibration signal generally exists in the vibration of thin-walled parts of aero-engines. According to relevant studies, the vibration amplitude of thin-walled parts of aero-engines is between tens of microns and hundreds of microns. Since thin-walled parts are often used as the main structural form in aero-engines, accurate and efficient acquisition of vibration signals of aero-engines' thin-walled parts is of great significance for research on vibration characteristics analysis, vibration reduction optimization design, and structur...

AI Technical Summary

Problems solved by technology

Optical measurement technology has the advantages of high precision, high sensitivity, non-contact, can be used in flammable and explosive harsh environments, and has no damage to the surface. It has become the main means of high-precision vibration measurement, such as laser vibration measurement and visual vibration measurement. Such methods can independently and objectively complete the measurement of the measured object. Among them, the displacement measured by the laser vibration measurement method can be as small as several microns, and the measurement accuracy can reach tens of nanometers, but the spatial resolution is low; the existing visual measurement method has high spatial resolution. Resolution, non-contact, simple operation, etc., but the measurement accuracy is limited

According to the latest research, the visual vibration measurement platform based on binocular stereo vision can measure the displacement of 0.1mm, but the measurement error reaches 0.028mm, and the diagonal field of view is only 0.2m

At the same time, for the two methods, due to the small vibration amplitude, the naked eye cannot judge and select the appropriate measurement position. To obtain the required measurement position points such as the data of the maximum amplitude position, it is necessary to measure the position of the measured object differently. With a large number of measurements, it is clear that this method is difficult to implement

[0004] To sum up, the existing vibration measurement technology cannot effectively solve the measurement problem of micro-amplitude vibration.

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