UA48774A - Method of noncontact measurement of parameters and determination of vibration oscillation modes of an object - Google Patents

Abstract

The proposed method of noncontact measurement of parameters and determination of vibration oscillation modes of an object involves recording intensity of an optical signal reflected from the vibrating object by using a high-speed videocamera. The amplitude, frequency, and mode of vibration oscillations of rotary or stationary objects are determined from the data obtained in processing videorecords, comparing these data with the records of vibration oscillations obtained by an automatic recorder.

Description

Description of the invention

The invention relates to measuring equipment and can be used to measure parameters of 2 mechanical vibrations of rotating and non-rotating objects.

A known method of non-contact measurement of object vibrations |1| consists in the fact that the object under investigation is probed by ultrasonic vibrations, the reflected frequency-modulated signal is received by the optical receiver, the probing and reflected signals are mixed, and two neighboring Doppler harmonics are separated from the received total signal. The amplitude of 70 oscillations of the object is determined in relation to the powers of these harmonics, and the frequency of oscillations is determined by the difference in their frequencies.

The disadvantage of the known method is that the method allows measuring the oscillations of only flat objects with a small amplitude of oscillations. When determining the oscillations of objects rotating with a low frequency and a large amplitude of oscillations, due to the curvature of the surface and the oscillations of the rotor, the reflected signal arrives with a delay, which leads to an error when superimposing the probing and reflected signals. The presented method 79 does not allow determining the form of oscillations of the objects under investigation. Also, the disadvantage is the use of complex original equipment.

The task of the proposed invention is to simplify the process of measuring vibration parameters and determining the forms of vibrations for rotating and non-rotating objects.

The task is achieved by recording the vibrations of the object using a high-speed video camera, and the amplitude, frequency and shape of the vibrations of both rotating and non-rotating objects are determined by processing video recordings on a personal computer and comparing them with the recording of vibrations on oscilloscope tape.

According to the invention, a high-speed video camera is installed in front of an oscillating object in a plane perpendicular to the direction of oscillations at a distance necessary to obtain a complete picture of the oscillations of the object or 29 of its individual elements. The layout of the equipment is shown in fig. where: « 1 - research object; 2 - high-speed video camera;

Z - personal computer; 4 - incandescent lamp; M 5 - vibrometer PY-19, part 6 - vibration sensor DN-5, 7 - oscilloscope HO71 4M in

Example of implementation: For a better viewing of the object's oscillation process, it was illuminated with a 4 in 1 kW incandescent lamp. Depending on the object's oscillation frequency, the working 325 video recording speed is selected on video camera 2.

To determine the vibration frequency of the object, a vibration sensor DN-5 6 is installed on its surface, the signal from which is fed to the input of the vibrometer PI-19 5. The amplified signal is recorded on the tape of the loop oscilloscope HO71 4M 7.

The resulting video footage is recorded on a personal computer Z using a video card with Z 70 video capture. This allows you to repeatedly view video frames with a recording of object vibrations and save individual fragments in the form of graphic files in the memory of a personal computer. Received files are processed

From" with the help of the graphic package AtsioSad, where the amplitude of oscillations is determined by graphical methods. Processing of the oscillographic tape allows you to determine the frequencies of oscillations of the object, and by comparing the frames of the video recording and the oscilloscope tape to determine the amplitudes of oscillations at these frequencies. The clarity and simplicity of the method allows you to visually determine the forms of oscillations of the object without using complex original equipment. shk The method was tested during the study of the vibrations of the boards of the shelf-type block on a vibrating stand and during the study of the vibrations of the rotating rotors - centrifuges of washing-spinning machines, which made it possible to measure with greater accuracy the shapes and amplitudes of the vibrations of objects in the entire working range Simplicity and visibility 7 method made it possible to obtain a complete picture of the objects' curves. - and 20 Literature:

AS Mo1262295. S.A. Martyugov, S.P. Andreev. The method of non-contact measurement of the oscillating object. Bul.

T" Mez7, 1986.

Claims (1)

The formula of the invention » A method of non-contact measurement of vibration parameters and determination of the forms of oscillations of objects, which includes registration by optical systems of electromagnetic waves that are reflected from an oscillating object, and determination of the parameters of vibrations of an object and its form of oscillations, which differs in that the registration the oscillations of the object 60 are carried out by a high-speed video camera, and the amplitude, frequency and form of oscillations of both rotating and non-rotating objects are determined by processing video recordings on a personal computer and comparing them with the recording of oscillations on the oscilloscope tape. b5