SU1283656A1 - Method of determining parameters of rotary motion of objects with diffuse scattering - Google Patents

Abstract

The invention can be used for remote control of rotating objects located in hard-to-reach places. The purpose of the invention is to expand the number of measurable motion parameters by measuring the beats of the surface of a rotating object. In addition, the divergence of the irradiation beam of laser I is measured, photoelectric recording of the scattered light in the Fraunhofer diffraction region with respect to the beam cross section in two regions perpendicular to the beam axis is carried out, then the distance between these two regions is monotonously varied. From the autocorrelation function obtained on the diaphragm 5 and the previously determined angular velocity, the distance from the irradiated area to the center of rotation and the measured angular divergence of the laser beam, the beating of the surface of the rotating object is judged. 1 pe. I (L

Description

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The invention relates to the measurement of motion parameters by optical methods and can be used to determine the beats of rotating objects located in hard to reach places.

The aim of the invention is to measure the beating of the surface of a rotating object.

The drawing shows a device for implementing the proposed method

The device contains a laser 1 and a telescope 2 which is optically aligned and optically aligned with it, a rotating object 3 in the form of a disk with holes, a telescope 4 and a diaphragm 5. The diaphragm 5 is a screen with four holes, grouped in pairs. The first pair is located circumferentially with the center on the beam axis, the Etora pair is located perpendicular to the beam axis. (I.e. on the drawing perpendicular to the circumference there are also radiation receivers 6 and 7 installed directly behind the pairs of holes in the diaphragm 5, autocorrelators 8 and 9 and the processing unit 10.

The method is implemented as follows.

Laser radiation from laser 1 is passed through a telescope 2, irradiates a rotating object 3 with it, forms a picture of a Fraunhofer diffraction from the dimensions of the irradiation beam on the diaphragm 5 with a telescope 4, and records the optical signal that has passed both holes A, A, the photoreceiver 6. The total signal from both the holes are transformed into electrical ones, and the autocorrelator torus 8 builds an autocorrelation signal function, norM1: based on its dispersion. By varying the distance between the holes A, A, on the diaphragm, an optimal view of the autocorrelation function with a p. Pronounced second maximum is obtained.

From the magnitude of the second maximum relative to zero, the angular velocity of rotation of the spotty pattern, and, consequently, the angular velocity of the volume under study, is determined from the magnitude of the second maximum relative to zero and the known radius of the circle where the holes are located.

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The second maximum determines the distance from the center of rotation of the object to the center of the irradiated area of the object and is calculated in block 10. After that, the divergence of the irradiation beam is measured, then the optical signal passing through the second pair B, B j is measured by a photodetector 7 The sum signal from both holes is converted into an electrical one, and autocorrelator 9 builds the autocorrelation signal function normalized to its dispersion. Varya the distance between the holes B ,. .B, on the diaphragm, the optimum form of the autocorrelation function is obtained by a pronounced second maximum.

From the known distance between the holes, the determined angular velocity of the object, the calculated distance from the center of rotation of the object to the center of the irradiated part of the object, the measured divergence of the laser beam, from the value of the second maximum of the autocorrelation function of the signal from the receiver 7 in block 10 calculate the beat value surface of a rotating object.

Claims (1)

Invention Formula The method for determining the parameters of rotational motion of diffusely scattering objects according to ed. St. No. 1046683, characterized in that, in order to measure the beating of a rotating, object, the divergence of the laser beam is measured and additional photoelectric registration of the scattered light is carried out in the Fraunhofer diffraction region relative to the cross section of the laser beam in two regions located on a plane perpendicular the beam axis, symmetrically with respect to a point of a circle of known radius with a center on the beam axis, then monotonously change the distance between these two regions and, using the obtained autocorrelation The function and the previously determined angular velocity, the distance from the irradiated area to the center of rotation, and the divergence of the laser beam determine the beats of the surface of the object.