CN101377405B - Vision measuring method of space round gesture parameter and geometric parameter - Google Patents

Abstract

The invention discloses a vision measurement method for spatial circular attitude parameter and geometric parameter, the coplanar geometrical elements on the spatial circular plain are introduced, and under the condition that the geometric parameter of the coplanar geometrical elements has been known, the non-contact measurement for the parameter of spatial circular radius and so on can be achieved. And the spatial circular attitude parameter can be obtained on the base. The parameter can be obtained just by using one camera. The vision measurement method is simple and easy and has good practicality and reliability.

Description

The vision measuring method of a kind of space round gesture parameter and geometric parameter

Technical field

The present invention relates to the pose measurement technology of space object, relate in particular to the vision measuring method of a kind of space round gesture parameter and geometric parameter.

Background technology

The problem of carrying out the space object pose measurement by single image be in the field of machine vision one basic and important problem all has extensively and important use at aspects such as vision guided navigation, robot location, object identification, vision monitoring and commercial measurements.So-called pose measurement refers to, under the condition that video camera has been demarcated, by the corresponding relation between space three-dimensional primitive (as point and straight line etc.) and the image two dimension primitive, try to achieve the rigid body transformation relation between camera coordinate system and the object coordinates system, thereby can access position and the attitude of object in camera coordinate system.

Pose localization method at present commonly used mainly comprises: based on spatial point to the localization method of picture point correspondence with based on the localization method of space line to image straight line correspondence.Comparatively speaking, stronger based on space line to the localization method noise resisting ability of image straight line correspondence, thus have better robustness.So-called robustness just is meant the robustness of system, and robustness is the key of system survival under unusual and dangerous situation.

Because circle is the basic geometric configuration of object, existence in a large number in many natural scenes and culture is as the pilot hole of various workpiece, parts etc.; The three-dimensional space position of the geometric center of these circles and the precision of radius of circle are to the successful installation of parts, and the integral body of object location, have great significance.Carry out in the method for spatial pose measurement based on single circle at present, the space geometry parameter of circle generally adopts three coordinate measuring machine to measure, the precision of three coordinate measuring machine can satisfy the measuring accuracy requirement of most of occasions to circle, but be subjected to the restriction in place, measurement can only be measured in the place that three coordinate measuring machine is installed, and can not satisfy the measurement needs of the especially large-scale circular hole in erecting stage.

Summary of the invention

In view of this, fundamental purpose of the present invention is to provide the vision measuring method of a kind of space round gesture parameter and geometric parameter, measures complicated and the limited problem of use occasion to solve prior art.

For achieving the above object, technical scheme of the present invention is achieved in that

The invention provides the vision measuring method of a kind of space round gesture parameter and geometric parameter, it is characterized in that, comprising:

Video camera is demarcated, obtained the inner parameter of video camera;

Obtain described video camera and take the measurement image that space circle obtains, and described measurement image is handled, obtain the elliptical edge point in the described measurement image and the unique point of geometric element;

According to the elliptical edge point in the described intrinsic parameters of the camera that obtains, the measurement image, the equation of fitted ellipse calculates the central coordinate of circle of space circle under camera coordinate system and the normal vector on plane, space circle place;

According to the center of circle of described space circle at the coordinate under the camera coordinate system, the normal vector of plane, space circle place under camera coordinate system, and the expression formula of measurement image midplane geometric element, calculate the expression formula of the space geometrical element corresponding with described geometric element;

Obtain the direction coefficient of space geometrical element according to the expression formula of space geometrical element, and obtain the angle of space geometrical element according to described direction coefficient; According to the relativeness between the space geometrical element, from the angle of space geometrical element, choose and obtain true angle, and the true normal vector on plane, definite space circle place;

According to the central coordinate of circle of described space circle and the true normal vector on plane, described space circle place, reach relativeness and known distance between the known space geometrical element, obtain the coordinate in the real space circle radius and the real space circle center of circle.

Described geometric element is orthogonal straight lines or parallel lines.

According to the Zhang Zhengyou planar process described video camera is demarcated.

By the Hessian matrix method described measurement image is handled, obtained the elliptical edge point in the described measurement image and the unique point of geometric element.

The described expression formula that calculates the space geometrical element corresponding with geometric element specifically comprises:

Obtain the equation of the projection plane of described geometric element according to the expression formula of described geometric element;

According to the coordinate of the center of circle under camera coordinate system of described space circle, and the normal vector of plane, described space circle place under camera coordinate system, determine two planes in the space;

According to the equation on determined two planes, and the equation of described projection plane, obtain the expression formula of two groups of space geometrical elements respectively.

The vision measuring method of a kind of space round gesture parameter provided by the present invention and geometric parameter, by the geometric element of introducing with plane, space circle place coplane, based on relativeness between the known spatial element and known distance, at first determined the attitude on plane, space circle place, under the condition of the geometric parameter of known coplane geometric element, realized non-contact measurement to space circle radius and space circle plane attitude parameter, only need a video camera to realize, and method of the present invention is simple, has better practicability and reliability.

Description of drawings

Fig. 1 is the process flow diagram of the vision measuring method of a kind of space round gesture parameter of the present invention and geometric parameter;

Fig. 2 is the synoptic diagram of digital two dimensional surface target among the present invention;

Fig. 3 is the synoptic diagram of space circle pose identification among the present invention;

Fig. 4 is the synoptic diagram that concerns of pose angle among the present invention and normal vector;

Fig. 5 is first width of cloth uncalibrated image in the embodiment of the invention;

Fig. 6 is second width of cloth uncalibrated image in the embodiment of the invention;

Fig. 7 is the 3rd width of cloth uncalibrated image in the embodiment of the invention;

Fig. 8 is the 4th width of cloth uncalibrated image in the embodiment of the invention;

Fig. 9 is the 5th width of cloth uncalibrated image in the embodiment of the invention;

Figure 10 is the synoptic diagram of the digital circular image that generates in the embodiment of the invention;

Figure 11 is for obtaining the ellipse on the plane of delineation and the synoptic diagram of straight line through Flame Image Process in the embodiment of the invention;

Figure 12 is the synoptic diagram of isolated ellipse and parallel lines in the embodiment of the invention.

Embodiment

The technical solution of the present invention is further elaborated below in conjunction with the drawings and specific embodiments.

The vision measuring method of a kind of space round gesture parameter provided by the present invention and geometric parameter as shown in Figure 1, is divided into calibration phase and measuring phases.

Calibration phase:

Step 101 is demarcated video camera, obtains the inner parameter of video camera.

Concrete operations are: 1) set target, target is the digital two dimensional surface target that computing machine generates, and as shown in Figure 2, has the chequered with black and white square of checkerboard on the target, and the unique point that sets in advance is arranged on the target.

The white square summit of choosing close center among Fig. 2 is a unique point, totally 14 * 18 unique points, certainly, the ranks number of unique point can be chosen according to actual needs, and also can freely choose required unique point quantity video camera being carried out timing signal, the unique point of selection is evenly distributed in the whole calibrating image as far as possible.Among Fig. 2, the length of side of black and white square is 50 pixels, and certainly, the length of side of black and white square all can be set according to actual needs.

2) fix the monocular vision sensor, open the power supply of video camera.

3) in the field range of video camera, move freely at least 5 positions of target, whenever move a position, take piece image and store in the computing machine by video camera, the image of among the present invention video camera in the calibration process being taken is called uncalibrated image, and require uncalibrated image to contain target unique point as much as possible, it is parallel to try not between the position of moving process midplane target.

4) extract the image coordinate on black square summit in all uncalibrated images, and the world coordinates of itself and target is stored in the computing machine.

5) (the specific implementation step is seen: calibrating camera Zhangzhengyou. " A flexible newtechnique for camera calibration. " MS Technical Report.Dec.21998) according to the Zhang Zhengyou planar process, obtain the inner parameter of video camera, and store in the computing machine.

It is pointed out that operation only need be carried out once getting final product to Camera calibration, but need guarantee in measuring process, the stationkeeping of video camera, and not significantly vibrations, otherwise, need carry out camera calibration again.Simultaneously, if twice measuring intervals of TIME is long, then be necessary video camera is demarcated again.

Measuring phases:

Step 102, obtain video camera and take the measurement image that space circle obtains, and by the Hessian matrix method (the specific implementation step is seen: Steger C.Unbiased Extraction of Curvilinear Structures from2D and 3D images.Dissertation.1998) measurement image is handled, obtained the elliptical edge point in the measurement image and the unique point of geometric element.

Wherein, measurement image is with in the measurement space of testee as for the monocular vision sensor, and takes the resulting image of space circle by video camera.Geometric configuration can be the orthogonal straight lines of coplane, also can be the parallel lines of coplane, certainly, can also adopt the geometric configuration that possesses other geometric properties according to actual needs.

Step 103, according to the intrinsic parameters of the camera that obtains, the elliptical edge point in the measurement image and the marginal point of geometric configuration, and by Safaree-Rad (the specific implementation step is seen: Reza Safaee-Rad, IvoTchoukanov, and BenHabib. " 3D Location Estimation of Circular Features forMachine Vision " IEEE Transaction on Robotics and Automation, VOL.8 NO.5 Oct.1992) method calculates the central coordinate of circle of single space circle under camera coordinate system and the normal vector on plane, space circle place.

It is pointed out that by single space circle and carry out pose when resolving that there are two in the normal vector that calculates plane, space circle place usually to be separated, and promptly has ambiguous problem.Purpose of the present invention is exactly to determine the true normal vector on plane, space circle place from these two normal vectors, thereby eliminates the ambiguity problem of space circle being carried out existence in the pose identification.

Wherein, the concrete operations of Safaree-Rad method are:

A, according to the inner parameter of elliptical edge point and video camera, match obtains the equation of elliptic equation and geometric configuration;

B, according to the coefficient and the focus of camera of elliptic equation, obtain the normal vector of plane, space circle place under camera coordinate system, and the coordinate of the center of circle of space circle under camera coordinate system.

Be specially: at first, according to the coefficient and the focus of camera of elliptic equation, the photocentre of setting up with video camera is the summit, is the space elliptic cone equation of bus with the ellipse; Again according to the coefficients to construct transformation matrix of space elliptic cone equation, and obtain the eigenwert and the proper vector of transformation matrix; Then,, obtain the normal vector of plane, space circle place under camera coordinate system, and, obtain the coordinate of the center of circle under camera coordinate system of space circle according to transformation matrix and space radius of a circle according to the eigenwert and the proper vector of transformation matrix.

Step 104, according to the center of circle of space circle at the coordinate under the camera coordinate system, the normal vector of plane, space circle place under camera coordinate system, and the expression formula of measurement image midplane geometric element, calculate the expression formula of the space geometrical element corresponding with geometric element.

Step 105, according to the expression formula of space element, and space geometrical element between relativeness, determine the true normal vector on plane, space circle place.

Step 106 according to the central coordinate of circle of described space circle and the true normal vector on plane, described space circle place, reaches the known spatial distance restraint, obtains the coordinate in the real space circle radius and the real space circle center of circle.

The parallel lines that with the geometric configuration is coplane below is an example, and above-mentioned measuring method is further elaborated.As shown in Figure 3, o _c-X _cY _cZ _cThe expression camera coordinate system, o _i-X _iY _iZ _iExpression camera review coordinate system, C is a space circle, π _sBe the plane at C place, π _iBe the plane of delineation of video camera, E _iFor C at π _iOn drop shadow curve, generally be oval, L ₁With L ₂Be π _sOn the pair of parallel straight line,

With

Be respectively the right projection plane of parallel lines, l ₁With l ₂For the space parallel straight line at π _iOn projection line.Focus of camera is f.

Known spatial circle C is at π _iOn be projected as elliptic curve E _i, then can determine one with E _iBe bus, with video camera photocentre o _cSpace elliptic cone for the summit.Determine π _sNormal vector at o _c-X _cY _cZ _cIn value, can be converted into and ask in the space certain plane L at o _c-X _cY _cZ _cIn plane equation, promptly asked for π _sNormal vector, thereby further can be in the hope of π _sAt o _c-X _cY _cZ _cUnder the pose angle, i.e. angle of pitch φ and azimuth angle theta, the relation of pose angle and normal vector as shown in Figure 4, the angle of pitch is the angle on normal vector n and xoy plane, the position angle is the projection n of n on the xoy plane _pAngle with x axle forward.The concrete implementation step of vision measuring method comprises:

Step 1 according to Zhang Zhengyou planar process calibrating camera, obtains the inner parameter A of video camera _Intr, and with A _IntrStore in the computing machine.Concrete camera calibration process aforementionedly has been described in detail, incessantly gives unnecessary details at this.

Step 2 is obtained video camera and is taken the measurement image that space circle obtains, and by the Hessian matrix method measurement image handled, and obtains elliptical edge point and linear edge point coordinate in the measurement image

And will

Store in the computing machine.

Step 3, according to the method for Safaree-Rad, establishing the space radius of a circle is r _Unit=1, r _UnitThe representation unit radius of a circle calculates at camera coordinate system o _c-X _cY _cZ _cDown, the central coordinate of circle C=(X of space circle _C0, Y _C0, Z _C0) and the value n of the normal vector on plane, space circle place ₁=(k ₁, l ₁, m ₁) ^T, n ₂=(k ₂, l ₂, m ₂) ^TThis shows that undertaken having ambiguity when pose resolves by space circle, promptly the normal vector on plane, space circle place exists two to separate in the ordinary course of things.

Step 4, the straight line L of space pair of parallel ₁And L ₂, it is at the plane of delineation π of video camera _iOn be projected as With

l ₁And l ₂Expression formula be respectively:

$l_1:\left\{\begin{array}{c}{a}_1{X}_c+b_1{Y}_c+c_1=0\\ Z_c=f\end{array}\right.---\left(1\right)$

$l_2:\left\{\begin{array}{c}{a}_2{X}_c+b_2{Y}_c+c_2=0\\ Z_c=f\end{array}\right.---\left(2\right)$

According to formula (1), (2) can be in the hope of l ₁And l ₂Corresponding projection plane is respectively:

${\mathrm{\π}}_{L_1}:a_1{X}_c+b_1{Y}_c+\frac{c_1}{f_{\mathrm{unit}}}{Z}_c=0---\left(3\right)$

${\mathrm{\π}}_{L_2}:a_2{X}_c+b_2{Y}_c+\frac{c_2}{f_{\mathrm{unit}}}{Z}_c=0---\left(4\right)$

Step 5 is by the n that obtains ₁, n ₂, C can determine two plane π in the space _sAnd π ' _s:

π _s：k ₁(X _c-X _c0)+l ₁(Y _c-Y _c0)+m ₁(Z _c-Z _c0)＝0 (5)

π′ _s：k ₂(X _c-X _c0)+l ₂(Y _c-Y _c0)+m ₂(Z _c-Z _c0)＝0 (6)

By formula (3), (4), (5) can be in the hope of the straight line in the space

With Expression formula be respectively:

$L_{1-1}:\frac{N_1{X}_c-b_1{w}_1}{L_1}=\frac{N_1{Y}_c+a_1{w}_1}{M_1}=Z_c---\left(7\right)$

$L_{2-1}:\frac{N_2{X}_c-b_2{w}_2}{L_2}=\frac{N_2{Y}_c+a_2{w}_2}{M_2}=Z_c---\left(8\right)$

Wherein, $(L_1,M_1,N_1)=(\left|\begin{array}{cc}{b}_1& c_1\\ l_1& m_1\end{array}\right|,\left|\begin{array}{cc}{c}_1& a_1\\ m_1& k_1\end{array}\right|,\left|\begin{array}{cc}{a}_1& b_1\\ k_1& l_1\end{array}\right|),$ w ₁＝-k ₁X _c0-l ₁Y _c0-m ₁Z _c0，

$(L_2,M_2,N_2)=(\left|\begin{array}{cc}{b}_2& c_2\\ l_1& m_1\end{array}\right|,\left|\begin{array}{cc}{c}_2& a_2\\ m_1& k_1\end{array}\right|,\left|\begin{array}{cc}{a}_2& b_1\\ k_1& l_1\end{array}\right|),$ w ₂＝-k ₁X _c0-l ₁Y _c0-m ₁Z _c0。

By (3), (4), (6) can be in the hope of the straight line in the space

And L _2-2The expression formula of=c " d " is:

$L_{1-2}:\frac{N_1^{\′}{X}_c-b_1{w}_1^{\′}}{L_1^{\′}}=\frac{N_1^{\′}{Y}_c+a_1{w}_1^{\′}}{M_1^{\′}}=Z_c---\left(9\right)$

$L_{2-2}:\frac{N_2^{\′}{X}_c-b_2{w}_2^{\′}}{L_2^{\′}}=\frac{N_2^{\′}{Y}_c+a_2{w}_2^{\′}}{M_2^{\′}}=Z_c---\left(10\right)$

Wherein, $(L_1^{\′},{M^{\′}}_1,N_1^{\′})=(\left|\begin{array}{cc}{b}_1& c_1\\ l_2& m_2\end{array}\right|,\left|\begin{array}{cc}{c}_1& a_1\\ m_2& k_2\end{array}\right|,\left|\begin{array}{cc}{a}_1& b_1\\ k_2& l_2\end{array}\right|),$ w′ ₁＝-k ₂X _c0-l ₂Y _c0-m ₂Z _c0，

$(L_2^{\′},{M^{\′}}_2,N_2^{\′})=(\left|\begin{array}{cc}{b}_2& c_2\\ l_2& m_2\end{array}\right|,\left|\begin{array}{cc}{c}_2& a_2\\ m_2& k_2\end{array}\right|,\left|\begin{array}{cc}{a}_2& b_1\\ k_2& l_2\end{array}\right|),$ w′ ₂＝-k ₂X _c0-l ₂Y _c0-m ₂Z _c0。

Step 6, the direction coefficient (L right according to the space line that calculates ₁, M ₁, N ₁) and (L ₂, M ₂, N ₂) calculated line L _1-1And L _2-1Angle α ₁And the direction coefficient right according to space line (L ' ₁, M ' ₁, N ' ₁) and (L ' ₂, M ' ₂, N ' ₂) calculated line L _1-1And L _2-1Angle α ₂Because the right collimation of space line does not keep under perspective projection transformation, if hypothesis π ₁Represent the true pose on plane, space circle place, then L _1-1And L _2-1Satisfy parallel relation, at this moment L _1-2And L _2-2Can regard L as _1-1And L _2-1With o _cBe the picture of the projective transformation at center, thereby two groups of space lines satisfy:

$\left\{\begin{array}{c}{(L_1,M_1,N_1)}^T\·{(L_1,M_2,N_2)}^T=1\\ {(L_1^{\′},{M^{\′}}_1,N_1^{\′})}^T\·{(L_2^{\′},{M^{\′}}_2,N_2^{\′})}^T\≠1\end{array}\right.---\left(11\right)$

Can judge the true normal direction value on plane, space circle place by formula (11).

Step 7, according to the value of the normal vector on the coordinate figure in the space circle center of circle that calculates and plane, space circle place, and thus can be according to step 3,4,5,6 calculate under camera coordinate system, the equation of space parallel straight line, and can calculate between the space parallel straight line apart from d _Unit

If two straight lines are respectively d to the distance in the space circle center of circle ₁And d ₂, if two straight lines are in the homonymy in the center of circle, d so _Unit=| d ₁-d ₂|, if two straight lines are in the heteropleural in the center of circle, d so _Unit=| d ₁+ d ₂|.

And, by geometric relationship as can be known, arbitrary space π that is parallel in the space _sPlane π _k, being circle with the section line of space elliptic cone, radius corresponding is r _k, while π _kWith projection plane

With

Intersection be parallel lines, and the distance between corresponding parallel lines is d _k, satisfy

If at supposition space circle radius is r _UnitCalculate under=1 the condition that space coplanar straight line sees apart from d _Unit, the distance in known spatial between two parallel lines is under the situation of d, can be in the hope of the true radius of space circle

Try to achieve after the real space circle radius, can try to achieve the true coordinate value of the space circle center of circle under camera coordinate system according to step 3.

By top description as can be seen, the present invention is by the geometric element of introducing with plane, space circle place coplane, relative position relation based on the coplane geometric element, at first determined the pose on plane, space circle place, under the condition of known spatial distance restraint, realized non-contact measurement to space circle radius and space circle plane attitude parameter, simple, and have better practicability and reliability.It is pointed out that geometric element is that the embodiment of the embodiment of orthogonal straight lines of coplane and parallel lines is similar, give unnecessary details no longer in detail among the present invention that difference is the intersection point of orthogonal straight lines and the distance in the space circle center of circle in the known spatial distance.

Further describe measurement effect of the present invention with specific embodiment more below.According to aforesaid operation steps, at first carry out Camera calibration, carry out the pose measurement of space circle then.

Calibration phase:

Adopt the ccd video camera of a Mintron-468P, 16mm Seiko camera lens is formed a monocular vision sensor.At first utilize target shown in Figure 2 that ccd video camera is demarcated, take 5 different positions and obtain 5 width of cloth images, extremely shown in Figure 9 as Fig. 5.Extract the unique point image coordinate among Fig. 5 to Fig. 9, and store in the computing machine; The upper left corner with computer screen is that initial point is set up the target coordinate system, and level is respectively x, the y axle forward of target coordinate system to the right straight down.

Use the Zhang Zhengyou planar process to carry out camera calibration, to obtain its inner parameter:

Intrinsic parameters of the camera: $A=\left(\begin{array}{ccc}2609.050& 0& 380.266\\ 0& 2604.876& 275.588\\ 0& 0& 1\end{array}\right)\mathrm{pixel},$

Distortion parameter is: (k ₁, k ₂)=(0.080996 ,-6.814367);

Calibration result, five width of cloth images on average again projection accuracy be E _RMS=0.115pixel;

Measuring phases:

Take the digital circular image that computing machine generates with video camera, wherein the coordinate of the center of circle in the target coordinate system is (512,384) pixel, as shown in figure 10, carries out the pose measurement of space circle according to above-mentioned step.

Obtain circle and straight line on the plane of delineation by Flame Image Process, for obtain ellipse and the straight line on the plane of delineation through Flame Image Process, Figure 12 is isolated ellipse and parallel lines as shown in figure 11.Through distortion correction, and with after the picture point coordinate transformation is to the normalization coordinate plane, equation and the right equation of coplane straight line that match obtains circular projection on the normalization coordinate plane are:

Equation of a circle: ${0.802X}_I^2+0.237X_I{Y}_I+0.549Y_I^2-{0.008X}_I+0.0006Y_I-0.0003=0;$

Straight-line equation: l ₁:-5.012X _I-Y _I-0.172=0, l ₂:-5.396X _I-Y _I+ 0.248=0.

The hypothesis space radius of circle is 1, tries to achieve its value under camera coordinate system of normal vector on plane, space circle place according to step 3:

n ₁＝(-0.590，-0.236，0.772，1) ^T

n ₂＝(0.598，0.233，0.767，1) ^T

The coordinate in the space circle center of circle is:

c ₁＝(0.2223，-0.0654，39.7872)pixel

c ₂＝(0.1993，-0.0745，39.7873)pixel

With the straight-line equation of the plane of delineation of match, L can be tried to achieve in through type (7), (8) _1-1And L _2-1Parameter be:

L _1-1：(L ₁，M ₁，N ₁) ^T＝(-0.8126，3.9714，0.5922) ^T

L _2-1：(L ₂，M ₂，N ₂) ^T＝(-0.7137，4.02，0.6827) ^T

Can calculate L thus _1-1And L _2-1Between angle be 1.8934 °.

In like manner, but through type (9), (10) are tried to achieve L _1-2And L _2-2Parameter be:

L _1-2：(L′ ₁，M′ ₁，N′ ₁) ^T＝(-0.7266，3.7399，-0.5804) ^T

L _2-2：(L′ ₂，M′ ₂，N′ ₂) ^T＝(-0.8245，4.2851，-0.6599) ^T

And calculate L _1-2And L _2-2Between angle be 0.1327 °.

And then can judge L _1-2And L _2-2The pose parameter of pairing space circle is real space circle pose parameter, and the normalization radius of circle pose parameter of the space circle that obtains is: n=(0.598,0.233,0.767) ^T, C=(0.1993 ,-0.0745,39.7873) pixel.

The distance that can further try to achieve between the straight line of the center of circle to two is respectively:

d ₁＝2.0137pixel，d ₂＝2.0085pixel；

So the distance in the space between two parallel lines is d=d ₁+ d ₂=4.0222pixel.

Distance between the coplane straight line on the known spatial disk is d ₀=400pixel, by step 11 as can be known, real space circle radius should be: r=d ₀/ d=99.4475pixel differs with real space circle radius r _ real=100pixel and to be that 0.5525pixel, relative accuracy are 5.53 ‰.

In addition, can try to achieve real space round gesture parameter on this basis is: n=(0.598,0.233,0.767,1) ^T, C=(19.823 ,-7.410,3956.745).

The above is preferred embodiment of the present invention only, is not to be used to limit protection scope of the present invention.

Claims (5)

1. the vision measuring method of space round gesture parameter and geometric parameter is characterized in that, comprising:

Video camera is demarcated, obtained the inner parameter of video camera;

Obtain described video camera and take the measurement image that space circle obtains, and described measurement image is handled, obtain the elliptical edge point in the described measurement image and the unique point of geometric element;

According to the elliptical edge point in the described intrinsic parameters of the camera that obtains, the measurement image, the equation of fitted ellipse calculates the central coordinate of circle of space circle under camera coordinate system and the normal vector on plane, space circle place;

According to the center of circle of described space circle at the coordinate under the camera coordinate system, the normal vector of plane, space circle place under camera coordinate system, and the expression formula of measurement image midplane geometric element, calculate the expression formula of the space geometrical element corresponding with described geometric element;

Obtain the direction coefficient of space geometrical element according to the expression formula of space geometrical element, and obtain the angle of space geometrical element according to described direction coefficient; According to the relativeness between the space geometrical element, from the angle of space geometrical element, choose and obtain true angle, and the true normal vector on plane, definite space circle place;

According to the central coordinate of circle of described space circle and the true normal vector on plane, described space circle place, reach relativeness and known distance between the known space geometrical element, obtain the coordinate in the real space circle radius and the real space circle center of circle.

2. according to the vision measuring method of described space round gesture parameter of claim 1 and geometric parameter, it is characterized in that described geometric element is orthogonal straight lines or parallel lines.

3. according to the vision measuring method of described space round gesture parameter of claim 1 and geometric parameter, it is characterized in that, described video camera is demarcated according to the Zhang Zhengyou planar process.

4. according to the vision measuring method of described space round gesture parameter of claim 1 and geometric parameter, it is characterized in that, described measurement image is handled, obtain the elliptical edge point in the described measurement image and the unique point of geometric element by the Hessian matrix method.

5. according to the vision measuring method of claim 1 or 2 or 3 or 4 described space round gesture parameter and geometric parameter, it is characterized in that the described expression formula that calculates the space geometrical element corresponding with geometric element specifically comprises:

Obtain the equation of the projection plane of described geometric element according to the expression formula of described geometric element;

According to the coordinate of the center of circle under camera coordinate system of described space circle, and the normal vector of plane, described space circle place under camera coordinate system, determine two planes in the space;

According to the equation on determined two planes, and the equation of described projection plane, obtain the expression formula of two groups of space geometrical elements respectively.

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