CN108955559A - Three-dimension measuring system structural parameters quick calibrating method under the conditions of one kind is non-parallel - Google Patents
Three-dimension measuring system structural parameters quick calibrating method under the conditions of one kind is non-parallel Download PDFInfo
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- CN108955559A CN108955559A CN201810275219.0A CN201810275219A CN108955559A CN 108955559 A CN108955559 A CN 108955559A CN 201810275219 A CN201810275219 A CN 201810275219A CN 108955559 A CN108955559 A CN 108955559A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
- G01B11/2433—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures for measuring outlines by shadow casting
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B21/00—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant
- G01B21/02—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant for measuring length, width, or thickness
- G01B21/04—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant for measuring length, width, or thickness by measuring coordinates of points
- G01B21/045—Correction of measurements
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- Length Measuring Devices By Optical Means (AREA)
Abstract
The invention discloses it is a kind of it is non-parallel under the conditions of three-dimension measuring system structural parameters quick calibrating method, its advantage may be implemented in projector lens and area array cameras camera lens line and calibration plane be it is non-parallel under the conditions of construct the mathematical model of projected fringe phase Yu object under test apparent height, the values of the structural parameters in measuring system mathematical model is obtained by a kind of quick calibrating method simultaneously, effectively improves precision compared to existing scaling method；Process are as follows: (1) establish it is non-parallel under the conditions of projected fringe phase and testee apparent height mathematical model；(2) stripe pattern that calibration plane is located at initial position is acquired by area array cameras；(3) fringe phase value of the calibration plane on initial position is sought；(4) stripe pattern that calibration plane is located at different location is acquired by area array cameras；(5) fringe phase value of the calibration plane on different location is sought；(6) phase difference value is input in mathematical model, simultaneous solution goes out system structure parameter.
Description
Technical field
The invention belongs to field of optical measuring technologies；It is related to a kind of quick mark of three-dimension measuring system model structure parameter
Determine method, can be used in the 3 D stereo information process using the measuring system acquisition object under test based on structured light projection,
Under the conditions of area array cameras and projector are in non-parallel, it is quickly obtained structural parameters in the system mathematic model.
Background technique
The calibration of system structure parameter is one of the critical issue in the three-dimensional measurement technology based on structured light projection, mark
Determine the accuracy that precision directly determines subsequent measuring targets three-dimensional reconstruction.Due to when actually building three-dimension measuring system
The equipment such as projector, area array cameras, testee, calibration plane are needed, usually in the ideal case, measurement mathematical model is established
In following condition: the line and testee position at projector optical center and area array cameras optical lens center are space
Parallel relation, while the optical axis of area array cameras is that vertical relation, projector optical axis and area array cameras optical axis intersect with calibration plane.
Then the mathematical model of the measuring system is derived by optic triangle method；But above-mentioned condition is to the building of measuring system, instrument
Put and the adjusting of device equipment propose strict requirements, while also limiting the flexibility that instrument and equipment is put；Otherwise pass through
The structural parameters for the measuring system that the mathematical model calibrates will generate large error, and then influence and obtain quilt using the system
The precision of object dimensional steric information is surveyed, will finally generate limitation to a certain extent to the practical application of the measuring system；Cause
It is difficult point that this, which finds the scaling method of the structural parameters of measuring system under non-ideal condition,.
Summary of the invention
The outstanding advantages of this method are able to achieve in projector lens center and area array cameras optical center line and calibration
When plane is angled, i.e., under the conditions of non-parallel, construct the number of projected fringe phase information Yu object under test apparent height
Relational model is learned, while values of the structural parameters in the measuring system mathematical model is obtained by a kind of quick calibrating method；It avoids
Parameter value is obtained by existing scaling method and the problem of error easily occurs, to effectively improve the precision of three-dimension measuring system.
The technical solution adopted by the present invention is three-dimension measuring system structural parameters Fast Calibration side under the conditions of one kind is non-parallel
Method, including the following steps:
(1) establish projector and area array cameras be it is non-parallel under the conditions of projected fringe phase information and testee surface
Height mathematical model；
(2) the setting calibration plane and initial position in high precision mobile platform, using projector by cosine distribution striped
On structured light projection to the calibration plane for being located at initial position, the striped of the location position plane surface is acquired by area array cameras
Image is as initial alignment image；
(3) fringe phase in initial alignment image is acquired using phase extraction algorithms to be distributed, pass through phase unwrapping algorithm
Obtain whole field fringes phase value of the calibration plane on initial position；
(4) using high precision mobile platform will demarcate plane be respectively moved to along camera optical axis direction it is different from initial plane
The position of distance；It is acquired respectively by area array cameras on each position after being modulated by calibration level variation generation phase
New stripe pattern, and as uncalibrated image；
(5) fringe phase on each position in uncalibrated image is acquired using phase extraction algorithms to be distributed, pass through phase solution
Wrap up algorithm and obtain whole field fringes phase value of the uncalibrated image on each position, and with initial position obtained in step (3)
On whole field fringes phase value make it is poor, obtain phase difference value；
(6) the multiple phase difference values obtained according to step (5) are input in the mathematical model as obtained in step (1),
Simultaneous solution goes out the system structure parameter in model.
The invention has the following advantages over the prior art:
1, it includes that equipment is more that the method in the present invention, which preferably solves the three-dimension measuring system based on structured light projection,
The problem of desired spatial relationships relatively difficult to achieve, the present invention this is proposed it is non-parallel under the conditions of system building, model foundation, and
It is deduced the mathematical relationship of phase difference and height, is laid a good foundation for subsequent three-dimensional reconstruction；
2, the method in the present invention preferably solves parameter in common scaling method and independently demarcates and lead to systematic survey
The problem of precision reduces；This method is lower to the requirement of three-dimension measuring system building structure, and calibration process is simple, accuracy is high,
For improving the accuracy and practicability important in inhibiting of the three-dimension measuring system based on structured light projection.
Detailed description of the invention
Fig. 1 is measuring system structural parameters calibration flow chart of the invention；
Fig. 2 be projector and area array cameras be it is non-parallel under the conditions of projected fringe phase and testee apparent height number
Learn model；
Fig. 3 is measuring system structural parameters calibration schematic diagram of the invention, wherein figure (a) is top view, figure (b) is three-dimensional
Structure chart；
Specific embodiment
Three-dimensional measurement structural parameters calibration process based on structured light projection of the invention is as shown in Figure 1, initially set up throwing
Shadow instrument and area array cameras be it is non-parallel under the conditions of projected fringe phase and testee apparent height mathematical model, under this model
The numerical relationship model for deriving phase height acquires calibration plane by area array cameras and is located at initial position and mobile hkIt is high
Stripe pattern after spending position recycles Fourier transform to extract fringe phase information and handle to obtain using Phase- un- wrapping complete
Field phase information, and by asking difference operation to obtain different height position and their phase difference value of initial position, utilize two height
Degree and phase difference relation equation, the parameter value in mathematical model can be obtained by simultaneous solution, effectively simplifies system calibrating
Process；For the measuring system parameters precision for further increasing calibration, calibration plane is carried out using high precision mobile platform multiple
Displacement, and the phase distribution under the conditions of different height with calibration plane initial position is sought respectively, utilize linear fit function
Acquire calibrating parameters value.With reference to the accompanying drawing, the specific implementation process of technical solution of the present invention is described in detail.
1. establish projector and area array cameras be it is non-parallel under the conditions of projected fringe phase information and testee surface it is high
Spend mathematical model
From Figure 2 it can be seen that under the conditions of non-parallel in phase height geometrical relationship model, if D is that testee surface is any
A bit, wherein EpEc=d, EcO=lo, ∠ EcEpEd=α, ∠ AEpO=β, ∠ EpOEd=θ, ∠ EcCO=δ, ∠ DAC=γ.If
It is distributed projecting light intensity where testee on the direction plane x in cosine function.Omitting each parameter footmark (x, y) condition
Under, for Δ OEdEp:
By sine in Δ AOEpIn, it can be obtained:
It is available similarly in Δ ACD:
Set up an office D height be h, then it represents that are as follows:
H=BD=CD sin δ (4)
It is derived by formula (3), (4):
Whereinf0For projected fringe spatial frequency, whereinTo project testee surface D
Point image corresponds to the phase of C point in calibration plane, if O point is space coordinate origin, thenTherefore in triangle Δ ECCO
In have:
It can be obtained by formula (2) and formula (6):
IfTo be projected to A point phase in measured object surface D point phase and corresponding calibration plane, area array cameras is adopted
The phase value of D point mapping calibration plane C point is in collection imageI.e.ThereforeFor testee surface D point and calibration
The phase difference of plane A point, due toIfIt can be obtained by joint in formula (5), (6), (7):
When formula (8) is projector lens center and area array cameras optical center line and calibration plane is any angle α
Phase height numerical relationship model.It is acquired by Fourier transformation phase extraction algorithms any one in collected stripe pattern
Point corresponding phase difference when demarcating plane and being located at initial position with itAfterwards, d, l need to be calibrated0, f0, α,After occurrence,
Testee surface this actual height information can be found out.
Measuring system mathematical model extends to two-dimensional space under the conditions of will be non-parallel, and introduces footmark (x, y), then formula
(8) become:
It can be obtained after formula (9) are carried out formal argument:
IfUnder the conditions of then non-parallel
Testee surface certain point height value can be derived with this relative to the phase difference value relationship of calibration plane initial position are as follows:
By formula (11) it is found that phase differenceWith object under test apparent height h (x, y) be non-zero when, inverse be line
Property corresponding relationship.Therefore two coefficient values of a (x, y) and b (x, y) need to only be calibrated, so that it may according to testee in stripe pattern
Surface arbitrary point phase value finds out the actual height value of the point.
2. acquiring calibration plane by area array cameras is located at the stripe pattern on initial position
The setting calibration plane and initial position h=0 in high precision mobile platform, using projector by cosine distribution striped
Structured light projection acquires the striped of the location position plane surface by area array cameras to being located in the calibration plane of initial position
Image is as initial alignment image；
3. seeking whole field fringes phase value of the calibration plane on initial position
It is acquired using Fourier transform phase extraction algorithms and collects fringe phase distribution map in initial alignment image, passed through
Phase unwrapping algorithm obtains whole field fringes phase value of the calibration plane on initial position
4. acquiring calibration plane by area array cameras is located at the stripe pattern on different location
As shown in figure 3, calibration plane is moved to and is demarcated respectively along the z-axis direction using high-precision two-dimensional mobile platform
Plan range is hkThe position of (x, y) (k=0,1,2...), i.e. height distance；Pass through area array cameras respectively on each position
Acquisition is changed by calibration level generates phase by modulated new stripe pattern, and as uncalibrated image.
5. seeking calibration plane in the whole field fringes phase value being located on different location
It is same to be become by Fourier after the stripe pattern being located on different location using area array cameras acquisition by calibration plane
It changes phase extraction algorithms and phase unwrapping algorithm acquires corresponding full field phase distributionThen itself and calibration
Plane initial position phase difference value are as follows:
6. multiple phase difference values according to acquisition are input in mathematical model, simultaneous solution goes out the ginseng of the system structure in model
Number
Due to demarcating the amount of movement of plane every time it is known that i.e. each height value hk(x, y) is known；When meeting k >=2, i.e.,
A (x, y) and b (x, y) can be determined by simultaneous formula.To improve system calibrating precision, it is corresponding that multiple different height value can be sought
Phase value, using least square method to different height, phase value carry out linear fit, to reduce calibrated error.
Claims (1)
1. the step of three-dimension measuring system structural parameters quick calibrating method is related under the conditions of one kind is non-parallel is as follows:
(1) establish projector and area array cameras be it is non-parallel under the conditions of projected fringe phase information and testee apparent height
Mathematical model；
(2) the setting calibration plane and initial position in high precision mobile platform, using projector by cosine distribution striated structure
Light is projected to being located in the calibration plane of initial position, and the stripe pattern of the location position plane surface is acquired by area array cameras
As initial alignment image；
(3) fringe phase in initial alignment image is acquired using phase extraction algorithms to be distributed, obtained by phase unwrapping algorithm
Demarcate whole field fringes phase value of the plane on initial position；
(4) plane will be demarcated using high precision mobile platform to be respectively moved to and initial plane different distance along camera optical axis direction
Position；It acquires to be changed by calibration level by area array cameras respectively on each position and generates phase by modulated new
Stripe pattern, and as uncalibrated image；
(5) fringe phase on each position in uncalibrated image is acquired using phase extraction algorithms to be distributed, pass through Phase- un- wrapping
Algorithm obtains whole field fringes phase value of the uncalibrated image on each position, and on initial position obtained in step (3)
It is poor that whole field fringes phase value is made, and obtains phase difference value；
(6) the multiple phase difference values obtained according to step (5) are input in the mathematical model as obtained in step (1), simultaneous
Solve the system structure parameter in model.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110849268A (en) * | 2019-12-10 | 2020-02-28 | 南昌航空大学 | Quick phase-height mapping calibration method |
| WO2020192265A1 (en) * | 2019-03-25 | 2020-10-01 | 同方威视技术股份有限公司 | Geometric parameter calibration piece and calibration method for ct device |
| CN112857260A (en) * | 2021-01-14 | 2021-05-28 | 成都铁安科技有限责任公司 | Stripe three-dimensional imaging calibration method and system thereof |
| CN113063368A (en) * | 2021-04-07 | 2021-07-02 | 杭州江奥光电科技有限公司 | Linear laser rotary scanning three-dimensional profile measuring method and device |
| CN114234847A (en) * | 2021-12-08 | 2022-03-25 | 苏州恒视智能科技有限公司 | Grating projection system and automatic correction and compensation method for grating phase shift height measurement |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1213072A (en) * | 1998-09-23 | 1999-04-07 | 西安交通大学 | Mohr phase demodulation method |
| US20010033386A1 (en) * | 2000-01-07 | 2001-10-25 | Kranz David M | Phase profilometry system with telecentric projector |
| CN101936718A (en) * | 2010-03-23 | 2011-01-05 | 上海复蝶智能科技有限公司 | Sine stripe projection device and three-dimensional profile measuring method |
| CN103528543A (en) * | 2013-11-05 | 2014-01-22 | 东南大学 | System calibration method for grating projection three-dimensional measurement |
| CN105866129A (en) * | 2016-05-16 | 2016-08-17 | 天津工业大学 | Product surface quality online detection method based on digital projection |
| CN106767528A (en) * | 2016-12-09 | 2017-05-31 | 佛山市安答科技有限公司 | A kind of scaling method of the grating three-dimension measuring system based on colored annulus scaling board |
-
2018
- 2018-03-26 CN CN201810275219.0A patent/CN108955559A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1213072A (en) * | 1998-09-23 | 1999-04-07 | 西安交通大学 | Mohr phase demodulation method |
| US20010033386A1 (en) * | 2000-01-07 | 2001-10-25 | Kranz David M | Phase profilometry system with telecentric projector |
| CN101936718A (en) * | 2010-03-23 | 2011-01-05 | 上海复蝶智能科技有限公司 | Sine stripe projection device and three-dimensional profile measuring method |
| CN103528543A (en) * | 2013-11-05 | 2014-01-22 | 东南大学 | System calibration method for grating projection three-dimensional measurement |
| CN105866129A (en) * | 2016-05-16 | 2016-08-17 | 天津工业大学 | Product surface quality online detection method based on digital projection |
| CN106767528A (en) * | 2016-12-09 | 2017-05-31 | 佛山市安答科技有限公司 | A kind of scaling method of the grating three-dimension measuring system based on colored annulus scaling board |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2020192265A1 (en) * | 2019-03-25 | 2020-10-01 | 同方威视技术股份有限公司 | Geometric parameter calibration piece and calibration method for ct device |
| US11340177B2 (en) | 2019-03-25 | 2022-05-24 | Nuctech Company Limited | Calibration assembly and method for calibrating geometric parameters of CT apparatus |
| CN110849268A (en) * | 2019-12-10 | 2020-02-28 | 南昌航空大学 | Quick phase-height mapping calibration method |
| CN112857260A (en) * | 2021-01-14 | 2021-05-28 | 成都铁安科技有限责任公司 | Stripe three-dimensional imaging calibration method and system thereof |
| CN113063368A (en) * | 2021-04-07 | 2021-07-02 | 杭州江奥光电科技有限公司 | Linear laser rotary scanning three-dimensional profile measuring method and device |
| CN114234847A (en) * | 2021-12-08 | 2022-03-25 | 苏州恒视智能科技有限公司 | Grating projection system and automatic correction and compensation method for grating phase shift height measurement |
| CN114234847B (en) * | 2021-12-08 | 2024-01-30 | 苏州恒视智能科技有限公司 | Grating projection system and grating phase shift height measurement automatic correction compensation method |
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