Summary of the invention
The purpose of the application is: in view of the above technical problems, the application proposes a kind of image distance measuring instrument and measurement method, with
Improve photogrammetric precision.
In order to achieve the above object, the technical solution of the application is:
A kind of image distance measuring instrument, including fuselage are provided with camera lens and figure corresponding with the camera lens in the fuselage
As sensor, it is additionally provided with laser range finder in the fuselage, it is being emitted from the image distance measuring instrument, produced by the laser range finder
The primary optical axis of raw laser beam and the camera lens is coaxial.
Laser deflection mirror is additionally provided in the fuselage, the laser beam that the laser range finder issues is through the laser deflection
The laser exit beam coaxial with the primary optical axis of the camera lens is obtained after mirror deflection processing.
The laser deflection mirror in the fuselage can be adjusted between the first position and the second position;
It is described when the laser deflection mirror is in the first position between the camera lens and described image sensor
The laser beam of laser range finder transmitting obtains coaxial with the primary optical axis of the camera lens after laser deflection mirror deflection processing
Laser exit beam;
When the laser deflection mirror is in the second position, the ambient light entered from the camera lens is without described
Laser deflection mirror and be emitted directly toward described image sensor.
When the laser deflection mirror is in the first position, the laser deflection mirror generates the laser range finder
Laser beam carry out 90 ° deflection.
The primary optical axis of the camera lens is vertical with the picture plane of described image sensor.
The optical centre for defining the camera lens is defined as the centre of image distance instrument, then measured by the laser range finder
Target range is distance of the centre to target.
It is provided in the fuselage for adjusting the laser deflection mirror between the first position and the second position
Repeated positioning device.
A kind of image distance measurement method is carried out using above-mentioned image distance measuring instrument, method includes the following steps:
1) the image distance measuring instrument is arranged in the first measurement erect-position, in the first measurement erect-position, will be surveyed from the image distance
Laser beam that amount instrument is emitted, being generated by the laser range finder is successively directed at several target points on testee, thus
The distance value of several target points on testee is measured respectively;Also, in the first measurement erect-position, also the image distance is measured
The camera lens of instrument is directed toward testee from different perspectives, includes the multiple pictures of target point to testee shooting;
2) the image distance measuring instrument is transferred to next measurement erect-position, repeated the above steps 1);
3) it repeats the above steps 2) several times, to measure each target on testee respectively in multiple measurement erect-positions
The distance value of point, respectively takes pictures to target point each on testee in multiple measurement erect-positions;
4) after multistation is measured, entirety is carried out the images of all single station shootings and together with measured distance value
It calculates;
Pixel coordinate system op- uv and photo coordinate system o-xy for indicating picture point as the position in plane, sit by pixel
Mark system op- uv is established on the image plane, with image upper left corner opFor coordinate origin, pixel is coordinate unit, each pixel
Coordinate (u, v) indicates pixel line number on the image and columns;In order to establish object space three-dimensional coordinate and image space
Perspective projection relationship between two-dimensional coordinate needs to be converted to pixel coordinate the photo coordinate system o-xy indicated with mm unit,
Using the primary optical axis of optical lens and imaging sensor as the intersection point o of plane is origin, x-axis, y-axis are respectively and image pixel coordinates
U axis, the v axis of system are parallel;Transforming relationship between photo coordinate system and pixel coordinate system is as follows:
In formula (1), dx and dy are that each pixel is expert at respectively to the physical size upward with column;u0And v0For principal point
Coordinate under pixel coordinate system.
Image space coordinate system S-xyz is for indicating that picture point in the position of image space, is fixed on optical lens and image
On sensor, based on optical lens projection centre S and imaging sensor;The origin of image space coordinate system S-xyz is optics
The key light overlapping of axles of the projection centre S of camera lens, z-axis and optical lens, perpendicular to as plane, x-axis, y-axis are flat with the picture respectively
The x-axis of areal coordinate system is parallel with y-axis, and So is the effective focal length f of optical lens;
Object coordinates system O-XYZ, for describing measured target in the position of object space;
If coordinate (X, Y, Z) of the object space point P under object coordinates system, coordinate under image space coordinate system be (X ', Y ',
Z '), coordinate of the corresponding picture point p in image space coordinate system is (x, y ,-f), seat of the projection centre S under object coordinates system
Mark (XS,YS,ZS);According to object space point, projection centre, the three point on a straight line condition of picture point, object coordinates system and image space coordinate are obtained
The relationship of transforming relationship and object space the point coordinate and picpointed coordinate of system:
In formula (2), R is the spin matrix that image space coordinate system is converted to object coordinates system, and the expression of spin matrix is used
Around the rotation angle (ε of three reference axisx,εy,εz) indicate,
R=Rx·Ry·Rz,
The positive direction of rotation is set as right-handed helix direction, i.e., from the axis positive axis to origin in terms of be counter clockwise direction, R is
Orthogonal matrix, R-1=RT;λ is scale factor,
Since in the actual imaging of camera, there are deviation (Δ x, Δ y) for its opposite theoretical position on as plane for picture point;It will
Above formula (2) is unfolded and eliminates scale factor, meanwhile, take the influence of picture point systematic error into account, available collinearity equation formula:
Picture point SYSTEM ERROR MODEL can be 10 parameter models, in addition to principal point deviation (x0,y0) and camera effective focal length f
It outside, further include radial distortion (k caused by lens shape mismachining tolerance1、k2、k3), bias caused by lens group optical center rigging error
Distort (p1、p2) and pixel the length and width dimension scale factor and as plane x-axis and y-axis it is non-orthogonal caused by as plane distort
(b1、b1);Using 10 parameter models, picture point systematic error is as follows:
In formula (4),
The laser ranging identifying body of the first location arrangements spherical shape of target point on the testee, then utilizes the picture
The distance value of the laser ranging identifying body is measured away from measuring instrument, the distance value of measured laser ranging identifying body is considered as correspondence
The distance value of target point.
The photography identifying body of the first location arrangements spherical shape of target point on the testee, is then surveyed using the image distance
Amount instrument measures the distance value of the sharp photography identifying body, and the image of captured photography identifying body is considered as the figure of corresponding target point
Picture.
The advantage of the application is:
The image distance instrument of the application design, during processing and manufacturing, be strict with the emergent ray of laser range finder with
The primary optical axis of camera lens is coaxial, meanwhile, the primary optical axis of camera lens and the picture plane of imaging sensor are vertical.By processing and manufacturing and
The method of later period compensation for calibrating errors realizes above-mentioned geometrical relationship.Therefore, during image distance measuring instrument list station is taken pictures, while to list
A point carries out ranging, this can be improved in the precision of image distance instrument shooting direction.Meanwhile being swashed using the high-precision of image distance instrument itself
Ligh-ranging value, when providing image calculation apart from benchmark and distance restraint, instead of the short baseline rod that existing technology uses,
The range of large scale distance restraint is increased, precision is further improved.
Specific embodiment
The application is described in further detail below by specific embodiment combination attached drawing.The application can be with a variety of
Different forms is realized, however it is not limited to embodiment described in the present embodiment.The purpose of following specific embodiments is provided
It is easy for becoming apparent from present disclosure thorough explanation, wherein the words of the indicating positions such as upper and lower, left and right is only needle
To shown structure in respective figure for position.
However, those skilled in the art may be aware that one or more detail description can be by
Omit, or can also adopt with other methods, component or material.In some instances, some embodiments are not described
Or it is not described later in detail.
In addition, technical characteristic described herein, technical solution can also be in one or more embodiments arbitrarily to close
Suitable mode combines.For those skilled in the art, it should be readily appreciated that method related with embodiment provided herein
Step or operation order can also change.Therefore, any sequence in drawings and examples is merely illustrative purposes, not secretly
Show requirement in a certain order, is required unless expressly stated according to a certain sequence.
It is herein component institute serialization number itself, such as " first ", " second " etc., is only used for distinguishing described object,
Without any sequence or art-recognized meanings.And " connection ", " connection " described in the application, unless otherwise instructed, include directly and
It is indirectly connected with (connection).
Fig. 1 shows a specific embodiment of this image distance measuring instrument of the application (i.e. the measuring instrument of image and distance),
The image distance measuring instrument includes fuselage 1 possessed by the photogrammetric equipment of traditional industry, and camera lens 2 and and mirror are provided in fuselage 1
Corresponding imaging sensor 3.
The key improvements of the present embodiment are: being additionally provided with a laser range finder 4 in above-mentioned fuselage 1, measure from the image distance
Instrument outgoing, the primary optical axis of laser beam and camera lens 2 that is generated by aforementioned laser rangefinder 4 it is coaxial.
In view of the primary optical axis of camera lens 2 should be vertical with the picture plane of imaging sensor 3, clapped to obtain optimal image
Take the photograph quality.If keeping the primary optical axis of the laser beam and camera lens 2 that are directly occurred by laser range finder 4 coaxially arranged, at least can
There are problems that one of following two:
Problem one:, can be because of the screening of laser range finder 4 if laser range finder 4 is arranged between camera lens 2 and imaging sensor 3
Gear, and cause imaging sensor 3 that cannot receive the light entered from camera lens 2, it is unable to complete image taking.
Problem two:, can be because of the screening of imaging sensor 3 if imaging sensor 3 is arranged between camera lens 2 and laser range finder 4
Gear, and the laser beam for causing laser range finder 4 to emit can not go out project from camera lens, so that the ranging to objective body cannot be completed.
If the installation site of above-mentioned laser range finder 4 or imaging sensor 3 in fuselage 1 is adjustable, can lead to
Overregulate the position of laser range finder 4 or imaging sensor 3, and make shooting when laser range finder 4 will not block from camera lens 2 into
The light entered, imaging sensor 3 will not block the laser beam of the transmitting of laser range finder 4 when ranging.
But, because the figure of laser range finder 4 and imaging sensor 3 is all bigger, to guarantee laser range finder 4 or figure
As installation site of the sensor 3 in fuselage 1 is adjustable, the figure of fuselage 1 will necessarily be arranged is very big, and disadvantage is obvious.
In view of the above-mentioned problems, the present embodiment uses a kind of simple and effective solution: being additionally provided with one in fuselage 1
Laser deflection mirror 5, the laser beam (original laser beam) that laser range finder 4 issues obtain after 5 deflection of laser deflection mirror processing
The coaxial laser exit beam with the primary optical axis of camera lens 2.Above-mentioned laser deflection mirror 5 in fuselage 1 can be in first position and
It is adjusted between two positions and aforementioned first position is between camera lens 1 and described image sensor 3.It is arranged in fuselage 1 useful
In the repeated positioning device for adjusting laser deflection mirror 5 between the first position and the second position.
When laser deflection mirror 5 is in the above-mentioned first position between camera lens 1 and imaging sensor 3, laser range finder 4 is sent out
The laser beam penetrated obtains the laser exit beam coaxial with the primary optical axis of camera lens 2 after 5 deflection of laser deflection mirror processing.Swash
The original laser beam that light deflecting mirror 5 issues is not directly coaxial with the primary optical axis of camera lens 2, but passes through the inclined of laser deflection mirror 5
The laser exit beam coaxial with the primary optical axis of camera lens 2 is obtained after turning processing.
More specifically, as shown in Figure 1, when laser deflection mirror 5 is in above-mentioned first position, laser deflection mirror 5 is by laser
The laser beam that rangefinder 4 generates carries out 90 ° of deflections.That is, original laser beam and camera lens 2 that laser deflection mirror 5 issues
Primary optical axis is vertical.
When laser deflection mirror 5 removes from first position and is in said second position, from the ambient light of the entrance of camera lens 2
Without going past laser deflection mirror 5, and it is emitted directly toward imaging sensor 3.
But, if laser deflection mirror 5 is arranged it is sufficiently small, to not influence the incident light of camera lens 2 in image sensing
Image quality on device 3, it is motionless can be fixed on a position for laser deflection mirror 5 in this case.
The primary optical axis of camera lens 2 is vertical with the picture plane of imaging sensor 3, to obtain optimal shooting quality.
The optical centre for defining camera lens 2 is defined as the centre of image distance instrument, then target measured by laser range finder 4 away from
With a distance from for centre to target.
When carrying out image distance measurement using this image distance measuring instrument of the present embodiment, successively following steps:
1) image distance measuring instrument is arranged in the first measurement erect-position first, it, will be from image distance measuring instrument in the first measurement erect-position
Laser beam being emitted, being generated by laser range finder 4 is successively directed at multiple (The more the better) target points on testee, thus
The distance value of multiple target points on testee is measured respectively;Also, in the first measurement erect-position, also by image distance measuring instrument
Camera lens 2 be directed toward testee from different perspectives, successively to shoot multiple pictures to testee, and guarantee captured photo
In the photo comprising at least one target point on testee.It is surveyed in this way, obtaining multiple target points and first on testee
The image measured the distance value of erect-position and measure multiple target points on the testee that erect-position is shot first.
" successively measuring " target point distance value each on testee described in above, does not imply that and is measuring a mesh
And then the distance value of next target point is measured after gauge length value until all target point distance values are continuously measured and finished.Together
Sample, above described " successively shoots " target point each on testee, does not also imply that after shooting a target point
And then next target point is shot until all target points are continuously shot completion.And refer to range measurement and the figure of each target point
Shooting successively carries out, it is impossible to carry out with time point.The measurement of above-mentioned a target point distance and the shooting of image, can phase interpenetrating
Row is injected, all target point distance values can also measured and then target point is shot.
Specifically in the present embodiment, we first carry out ranging to first aim point, and image distance measuring instrument is fixed, immediately
Take pictures to the first aim point.Then ranging is carried out to second target point, image distance measuring instrument is fixed, immediately
Take pictures to the second target point.So operating is advantageous in that, image distance measuring instrument surveys the same target point
Away from shooting when position and angle it is completely the same, ensure that postorder to the computational accuracy of testee model.
If do not handled the target point on testee, and directly by the laser beam directive measured object of image distance measuring instrument
The target point (i.e. the location point of testee itself) of body, it is understood that there may be the laser beam of homed on its target point can only marginally or completely
Image distance measuring instrument cannot be reflexed to, ranging quality and low precision are caused.So the position of the first target point on testee of the present embodiment
The spherical laser ranging identifying body of arrangement is set, it is measured then using the distance value of image distance measuring instrument measurement laser ranging identifying body
The distance value of laser ranging identifying body be considered as the distance value of corresponding target point
Laser ranging identifying body has good laser reflection ability, its received laser beam can largely be reflexed to image distance measurement
Instrument, accurately to measure distance value.
Similarly, if do not handled the target point on testee, and directly to target point (the i.e. quilt of testee
Survey the location point of object itself) it takes pictures, it is difficult to guarantee the quality of shooting image, and is difficult to pick out target point in image
Position.So the photography identifying body of the first location arrangements spherical shape of target point on testee of the present embodiment, then utilizes image distance
Measuring instrument shooting photography identifying body, the image of captured photography identifying body are considered as the image of corresponding target point.
2) image distance measuring instrument is transferred to next measurement erect-position (image distance measuring instrument is moved to next measurement position), weight
Multiple above-mentioned steps 1).
3) it repeats the above steps 2) several times, to measure each target on testee respectively in multiple measurement erect-positions
The distance value of point, respectively takes pictures to target point each on testee in multiple measurement erect-positions.To obtain on testee
The distance value and each target point on the testee of each measurement erect-position shooting of each target point and each measurement erect-position
Image.
4) after multistation is measured, entirety is carried out the images of all single station shootings and together with measured distance value
It calculates, specific as follows:
Pixel coordinate system op- uv and photo coordinate system o-xy for indicating picture point as the position in plane, sit by pixel
Mark system op- uv is established on the image plane, with image upper left corner opFor coordinate origin, pixel is coordinate unit, each pixel
Coordinate (u, v) indicates pixel line number on the image and columns;In order to establish object space three-dimensional coordinate and image space
Perspective projection relationship between two-dimensional coordinate needs to be converted to pixel coordinate the photo coordinate system o-xy indicated with mm unit,
Using the primary optical axis of optical lens and imaging sensor as the intersection point o of plane is origin, x-axis, y-axis are respectively and image pixel coordinates
U axis, the v axis of system are parallel;Transforming relationship between photo coordinate system and pixel coordinate system is as follows:
In formula (1), dx and dy are that each pixel is expert at respectively to the physical size upward with column;u0And v0For principal point
Coordinate under pixel coordinate system.
Image space coordinate system S-xyz is for indicating that picture point in the position of image space, is fixed on optical lens and image
On sensor, based on optical lens projection centre S and imaging sensor;The origin of image space coordinate system S-xyz is optics
The key light overlapping of axles of the projection centre S of camera lens, z-axis and optical lens, perpendicular to as plane, x-axis, y-axis are flat with the picture respectively
The x-axis of areal coordinate system is parallel with y-axis, and So is the effective focal length f of optical lens.
Object coordinates system O-XYZ, also referred to as global coordinate system, for describing measured target in the position of object space.
If coordinate (X, Y, Z) of the object space point P under object coordinates system, coordinate under image space coordinate system be (X ', Y ',
Z '), coordinate of the corresponding picture point p in image space coordinate system is (x, y ,-f), seat of the projection centre S under object coordinates system
Mark (XS,YS,ZS);According to object space point, projection centre, the three point on a straight line condition of picture point, object coordinates system and image space coordinate are obtained
The relationship of transforming relationship and object space the point coordinate and picpointed coordinate of system:
In formula (2), R is the spin matrix that image space coordinate system is converted to object coordinates system, and the expression of spin matrix can
With with the rotation angle (ε around three reference axisx,εy,εz) indicate, generally also write asR=Rx·Ry·Rz。
The positive direction of rotation is set as right-handed helix direction, i.e., from the axis positive axis to origin in terms of be counter clockwise direction, R is
Orthogonal matrix, R-1=RT;λ is scale factor.
Since in the actual imaging of camera, there are deviation (Δ x, Δ y) for its opposite theoretical position on as plane for picture point;It will
Above formula (2) is unfolded and eliminates scale factor, meanwhile, take the influence of picture point systematic error into account, available collinearity equation formula:
Common picture point SYSTEM ERROR MODEL can be 10 parameter models, in addition to principal point deviation (x0,y0) and camera it is effective
It further include radial distortion (k caused by lens shape mismachining tolerance outside focal length f1、k2、k3), lens group optical center rigging error causes
Decentering distortion (p1、p2) and pixel the length and width dimension scale factor and as plane x-axis and y-axis it is non-orthogonal caused by as flat
Area distortion (b1、b1);Using 10 parameter models, the systematic error of picture point is as follows:
In formula (4),
The present embodiment uses the thinking of multistation multi-class data fusion treatment, and digital picture and distance measurement value are carried out whole ask
Solution, provides standard and dimensional constraints by the precision distance measurement value of laser range finder for image measurement, to improve most
Whole measurement accuracy.
The foregoing is a further detailed description of the present application in conjunction with specific implementation manners, and it cannot be said that this Shen
Specific implementation please is only limited to these instructions.For those of ordinary skill in the art to which this application belongs, it is not taking off
Under the premise of from the application design, a number of simple deductions or replacements can also be made.