CN103557809A - Multipoint angle measuring device based on CCD - Google Patents

Abstract

Provided is a multipoint angle measuring device based on a CCD. Multiple light spot images are collected through the CCD, and multiple measuring point angles are measured through a computer image processing algorithm. The device is simple in structure, easy and convenient to operate and suitable for multipoint angle measurement.

Description

A kind of multiple spot angle measurement unit based on CCD

Technical field:

The present invention relates to a kind of angle measurement unit, specifically a kind of multiple spot angle measurement unit based on CCD.

Background technology:

Angle measurement unit is conventional laser interferance method, directional light method and grating measuring method etc.Measurements by laser interferometry precision is high, but is easily subject to surrounding environment influence.Grating measuring method complex structure cost is high, can only be for short distance measurement of angle.Patent 97251378.7 discloses a kind of high-precision automatic angle measurer, and the method adopts autocollimation directional light method, process the image that CCD gathers, but the method can only be measured the angle at a measuring point place by microcomputer and image pick-up card.

Summary of the invention:

The object of the invention is to provides a kind of multiple spot angle measurement unit based on CCD for the deficiencies in the prior art.This device adopts CCD and laser to carry out multiple spot measurement of angle, and measuring accuracy is high, and automaticity is high, easy and simple to handle.

Technical scheme of the present invention: a kind of multiple spot angle measurement unit based on CCD, many laser tube transmitting multiple lasers are to a plurality of measuring point catoptrons of measured piece, the multi beam reflected light of catoptron forms luminous point group on same screen, CCD imports luminous point group image into computing machine, is processed the angle that obtains produced simultaneously a plurality of measuring points place by computing machine.

The invention has the beneficial effects as follows: compared with the prior art, the present invention is a kind of multiple spot angle automatic testing equipment based on CCD, and simple in structure, measuring accuracy is high, and automaticity is high, easy and simple to handle.

Accompanying drawing explanation:

Fig. 1 is structural representation of the present invention.

Fig. 2 is measuring point angle measurement schematic diagram.

Mark in figure: 1 measured piece, 2 catoptrons, 3 laser tubes, 4 screens, 5CCD, 6 computing machines.

Embodiment:

As shown in Figure 1, the multiple spot angle measurement unit based on CCD.Comprise 1 measured piece, 2 catoptrons, 3 laser tubes, 4 screens, 5CCD, 6 computing machines.

On described measured piece 1, stick at selected measuring point place 5 measuring points in catoptron 2(Fig. 1), 5 laser tubes 3 incide respectively each measuring point place, by catoptron 2, are reflexed on screen 4 at a distance.CCD5 gathers 5 dot pattern pictures on screen 4, imports computing machine 6 into and carries out image processing.

Computing machine 6 calculates 5 luminous point coordinates, obtains 5 measuring point angles, and result is presented on computer screen, and is kept in data file.

Measuring principle is as follows:

Computing machine is divided into entire image the reflected light variation range of the corresponding measuring point in ，Mei Kuai region, 5 regions, when measured object distortion causes that catoptron rotates, when each luminous point moves on screen 4, corresponds to luminous point coordinate in image and moves.

Single luminous point changes as shown in Figure 2, if laser incides measuring point place catoptron back reflection to A point on screen before loading, load back reflection light and move to B point on screen, A, B two spot distance are d, measuring point is S to screen distance, and the corner b of measuring point place has computing formula: b=d/ (2*S).

Wherein spot distance d is obtained by image processing program.Adopt grey scale centre of gravity formula:

$x_C=\frac{{\mathrm{\Σ}}_{i_0}^{i_f}{\mathrm{\Σ}}_{j_0}^{j_f}j(T-f_{\mathrm{ij}})}{{\mathrm{\Σ}}_{i_0}^{i_f}{\mathrm{\Σ}}_{j_0}^{j_f}(T-f_{\mathrm{ij}})}$

$y_C=\frac{{\mathrm{\Σ}}_{i_0}^{i_f}{\mathrm{\Σ}}_{j_0}^{j_f}i(T-f_{\mathrm{ij}})}{{\mathrm{\Σ}}_{i_0}^{i_f}{\mathrm{\Σ}}_{j_0}^{j_f}(T-f_{\mathrm{ij}})}$

In formula T be dot pattern as gray threshold, f is the gray-scale value of each pixel, x and y are luminous point gray scale centre coordinates.The difference of two luminous point grey scale centre of gravity coordinates is spacing d.

In image processing system, spot distance precision is 0.1 millimeter, and measuring point is 5 meters to screen distance, and measuring point place outer corner measurement precision is 0.1/ (2*5000), i.e. 0.00001 radian.

Claims (1)

1. the multiple spot angle measurement unit based on CCD, it is characterized in that: many laser tubes (3) transmitting multiple laser is to a plurality of measuring point catoptrons (2) of measured piece (1), the multi beam reflected light of catoptron (2) is in the upper luminous point group that forms of same screen (4), CCD(5) import luminous point group image into computing machine (6), by computing machine (6), processed the angle that obtains produced simultaneously a plurality of measuring points place.

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