CN106441163B - A kind of contactless column measuring for verticality method and device - Google Patents

Abstract

The invention discloses a kind of contactless column measuring for verticality method and devices.The present invention is realized using binocular high-definition camera and laser rays to the real-time measuring for verticality of columnar object, laser rays is as vertical reference, column is imaged in binocular high-definition camera, pass through Edge check and line detection method, it realizes and columnar object edge placement is demarcated, by comparing in a certain range with the columnar verticality of the range measurement of reference line, may be implemented by this programme to columnar high accuracy non-contact, measurement accuracy is at 0.05 °；Two viewing field of camera range Theta=62 °, resolution ratio are used to be located among two cameras for 5K × 5K camera, camera horizontal sextant angle Φ=60 °, one rack of laser, one or more of horizontal and vertical laser rays can be emitted, length is determined according to the height of tested column, laser line length is less than or equal to the height of column, a small-sized industrial personal computer realizes that the squareness measurement to cylinder iron core, device production are simple and convenient to operate, measure accurately.

Description

A kind of contactless column measuring for verticality method and device

Technical field

The present invention relates to industrial measuring for verticality technology, refer specifically to detected column workpiece whether vertical-horizontal work Make the method for platform, it be applied to industrial production, installation and debugging work in, particularly suitable for it is especially big and can not contact measurement ring Border.

Background technique

With the continuous development of machine vision, machine vision mainly simulates the visual performance of people with computer, is not only The simple extension of human eye, it is often more important that the part of functions with human brain --- information is extracted from the image of objective things, It is handled and is understood, eventually for actually detected, measurement and control.The development of existing visible optical sensing, point The application that resolution continuous improvement is machine vision in industrial detection provides extensive space and use scope.Low cost swashs Light technology is constantly mature, has been widely used in industrial production and manufacturing and has received, and the present invention is combined real by machine vision and laser Now to the contactless measuring for verticality of columnar object, it is with a wide range of applications in particular industry production, so that vertically It is easy to detect, quick, accurate to spend.

Summary of the invention

In order to overcome the shortcomings of that physical contact formula measures, the present invention provides a kind of contactless column type object measuring methods And device, this method and device can quickly, in real time, accurately to the measuring for verticality of columnar object.

A kind of contactless column type object measuring method of the present invention the following steps are included:

Step 1: setting covers the laser rays of tested cylindrical objects, and laser rays is as standard vertical referential.Laser Emit vertical linearity laser, laser strip number can be one or more of, can also increase a horizontal laser line as horizontal ginseng It examines, vertical linearity laser rays is as standard vertical referential；

Step 2: making Edge check extraction to binocular camera respectively, extracts column type object edge.Edge based on search Detection method calculates edge strength first, Edge Detection can make Robert operator, Prewitt operator, Sobel operator, Laplacian operator, Canny operator realize edge detection, while carrying out smooth treatment by filtering algorithm.Usually led with single order Number indicates, obtains the gradient of initial data brightness, by this information can search peak in the picture, if I (x) indicates x The brightness of point, then derivative I ' (x) of I (x) indicates are as follows:

I ' (x)=- 1/2*I (x-1)+I (x) -1/2*I (x+1)

Method based on zero crossing is by positioning margin location by the zero cross point for finding the second dervative that image obtains It sets.This method is to seek the change rate of image gradient, and logical zero-crossing examination obtains the local maximum of gradient, and I " (x) can be with table It is shown as:

I " (x)=- I (x-1)+2*I (x)-I (x+1)

Step 3: doing straight-line detection to edge testing result, detects the column type edge of column type object, and smooth, denoising makes figure There was only reference laser lines and tested cylindrical objects cylindrical rim as in.Utilize Hough transformation, Freeman criterion isoline detection side Method realizes straight-line detection.Straight line is ax+by=1 in the general expression of x-y coordinate system, and x, y are projected to a-b as known quantity In coordinate system, any point (x, y) is a curve in a-b coordinate system, and (a, b) of curve intersection most multiple spot is exactly straight line The parameter of equation；Point on image is detected by Hough transformation, and it is most to search curve intersection in a-b coordinate system, this intersection point (a, b) is the parameter of straight line.

Step 4: the deviation of bidimensional is calculated in two edges and vertical reference laser straight line of column type object, calculates inclined Gap from.Column type object two sides straight line in Δ H difference in height both ends and reference laser line pixel difference calculate certain it is one-dimensional on Deflection, Δ N × image resolution ratio are equal to deflection distance.Columnar object skew direction and angle of deviation is calculated by bidimensional Degree.By calculate X, Y-direction deflection distance obtain the angle excursion of columnar object in the x, y direction, according to X, Y-direction it is inclined It tiltedly is mapped to plane coordinate system direction, skew direction is shown using bubble method, determines bubble apart from the center of circle according to angle excursion Distance, X-direction Computing Principle is cylindrical objects edge straight line and difference in height is deviation △ S, the △ S of H criterion distance laser baseline =(s2-s1), deviation angle tan (θ)=△ S/H；

Compared with prior art, the beneficial effects of the invention are as follows

1. various scenes are adapted to, not by environmental restrictions.

2. it is contactless, it is adapted to special popular environment (personnel measure inconvenient).

Detailed description of the invention

Fig. 1 is the contactless column measuring for verticality method schematic diagram of the present invention.

S1 is that two camera distances are tested columnar object distance；S2 is distance between two cameras；

θ is the visual field angular coverage of camera；Φ is camera and horizontal sextant angle range；

Fig. 2 is laser rays schematic diagram of the present invention.

Fig. 3 is the contactless column measuring for verticality method schematic of the present invention.

Fig. 4 is electronics processing detection functional diagram of the present invention.

Fig. 5 is the electronics bubble schematic diagram of testing result of the present invention.

Specific embodiment

For enterprise demand, designs set of device and realize to the real-time measuring for verticality of cylinder iron core, worker is instructed to install. Enterprise demand include: 1000~2300mm of cylinder iron core height, 350~1200mm of cylinder iron core diameter, 0.05 ° of detection accuracy~ 0.1°.Design parameter as shown in figure 1 S1=2000mm, S2=1000mm, viewing field of camera range Theta=62 °, camera horizontal sextant angle Φ= One 60 °, laser rays length=2500mm.Practical Project realizes 0.08 ° of measurement accuracy, meets design requirement.

Claims (1)

1. a kind of verticality measuring method of contactless column verticality measurement device, it is characterised in that application one kind is non-to be connect Touch column verticality measurement device, the device include two cameras, laser and industrial personal computer,

Two viewing field of camera ranges are 62 °, and resolution ratio is 5K × 5K；

The laser is LED laser device；

Two cameras are placed relative to tested column bilateral symmetry, and two cameras are with horizontal line horizontal sextant angle Φ 60 °, the distance between camera and distance meets viewing field of camera coverage area between testee, the object space resolution ratio of camera is extremely Less in the accuracy rating of 1mm；

The laser is located among two cameras, generates the laser that one or more length is less than or equal to column height Line；

The industrial personal computer does Edge check and straight-line detection, realization pair to the two images information obtained respectively from two cameras Column X, Y-direction deviation calculate, and realize to column squareness measurement:

Include the following steps:

(1) laser emits vertical linearity laser, and laser strip number is one or more of, or increases a horizontal laser line and make For horizontal reference, vertical linearity laser rays is as standard vertical referential；

(2) Edge check and filtering carried out to the image that is obtained by camera, Edge Detection using Robert operator, Prewitt operator, Sobel operator, Laplacian operator or Canny operator, while smooth treatment is carried out by filtering algorithm； The gradient that initial data brightness is usually indicated with first derivative, by this information can search peak in the picture, I (x) table Show the brightness of x point, derivative I ' (x) of I (x) indicates are as follows:

I ' (x)=- 1/2*I (x-1)+I (x) -1/2*I (x+1)

Method based on zero crossing is to position marginal position by finding the zero cross point for the second dervative that image obtains, this Method is to seek the change rate of image gradient, and logical zero-crossing examination obtains the local maximum I " (x) of gradient, and I " (x) is indicated are as follows:

I " (x)=- I (x-1)+2*I (x)-I (x+1)

(3) straight-line detection is carried out to the image information of Edge check and filtering processing, detect columnar object two sides edge and Laser rays；Straight-line detection is realized using Hough transformation, Freeman criterion line detection method；Expression of the straight line in x-y coordinate system Formula is ax+by=1, x, y is projected in a-b coordinate system as known quantity, any point (x, y) is in a-b coordinate system (a, b) of one curve, curve intersection most multiple spot is exactly the parameter of linear equation；Point on image is detected by Hough transformation, It is most to search curve intersection in a-b coordinate system, this intersection point (a, b) is the parameter of straight line；

(4) it is one-dimensional to calculate certain for the pixel difference at the both ends and reference laser line according to column type object two sides straight line in Δ H difference in height On deflection, Δ N × image resolution ratio be equal to deflection distance, Δ N be pixel distance values size, pass through calculate X, Y The deflection distance in direction obtains the angle excursion of columnar object in the x, y direction, is mapped to plane according to the deflection of X, Y-direction and sits Mark system direction shows skew direction using bubble method, determines that distance of the bubble apart from the center of circle, X-direction calculate according to angle excursion Principle is cylindrical objects edge straight line and difference in height is deviation △ S, the △ S=(S2-S1) of H criterion distance laser baseline, S2, S1 The respectively size of the distance values at both ends of the cylindrical objects edge straight line in H difference in height and laser baseline, deviation angle tan (θ)=△ S/H, same principle calculate Y-direction.