CN108362469B - Size and surface pressure measurement method and apparatus based on pressure sensitive paint and light-field camera - Google Patents
Size and surface pressure measurement method and apparatus based on pressure sensitive paint and light-field camera Download PDFInfo
- Publication number
- CN108362469B CN108362469B CN201810041152.4A CN201810041152A CN108362469B CN 108362469 B CN108362469 B CN 108362469B CN 201810041152 A CN201810041152 A CN 201810041152A CN 108362469 B CN108362469 B CN 108362469B
- Authority
- CN
- China
- Prior art keywords
- picture
- pressure
- value
- model
- light
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000003973 paint Substances 0.000 title claims abstract description 44
- 238000000034 method Methods 0.000 title claims description 15
- 238000009530 blood pressure measurement Methods 0.000 title description 6
- 238000009826 distribution Methods 0.000 claims abstract description 47
- 238000005259 measurement Methods 0.000 claims abstract description 16
- 238000000691 measurement method Methods 0.000 claims abstract description 14
- 238000003825 pressing Methods 0.000 claims abstract description 13
- 230000004927 fusion Effects 0.000 claims abstract description 4
- 230000000007 visual effect Effects 0.000 claims description 61
- 238000013519 translation Methods 0.000 claims description 42
- 239000011159 matrix material Substances 0.000 claims description 22
- 238000012937 correction Methods 0.000 claims description 17
- 238000004364 calculation method Methods 0.000 claims description 13
- 238000003384 imaging method Methods 0.000 claims description 7
- 238000006073 displacement reaction Methods 0.000 claims description 6
- 230000003287 optical effect Effects 0.000 claims description 6
- 241000208340 Araliaceae Species 0.000 claims description 5
- 235000005035 Panax pseudoginseng ssp. pseudoginseng Nutrition 0.000 claims description 5
- 235000003140 Panax quinquefolius Nutrition 0.000 claims description 5
- 230000005284 excitation Effects 0.000 claims description 5
- 235000008434 ginseng Nutrition 0.000 claims description 5
- 230000009466 transformation Effects 0.000 claims description 3
- 238000010586 diagram Methods 0.000 claims 1
- 235000013399 edible fruits Nutrition 0.000 claims 1
- 238000005516 engineering process Methods 0.000 description 11
- 230000007547 defect Effects 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 230000001195 anabolic effect Effects 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000007499 fusion processing Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012634 optical imaging Methods 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 238000012805 post-processing Methods 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 230000011218 segmentation Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M9/00—Aerodynamic testing; Arrangements in or on wind tunnels
- G01M9/06—Measuring arrangements specially adapted for aerodynamic testing
Abstract
The present invention provides the measurement methods of a kind of three-dimensional dimension based on pressure sensitive paint and light-field camera and surface pressing comprising the steps of: picture obtaining step: obtaining the pressure signal light field picture and depth signal light field picture of model respectively；Surface pressure distribution calculates step: model surface pressure-plotting is calculated from pressure signal light field picture；Case depth distribution calculates step: model surface depth profile is calculated from depth signal light field picture；Three-dimensional pressure is distributed generation step: the information of Fusion Model surface pressure distribution figure and the information of model surface depth profile generate threedimensional model pressure-plotting.The present invention also provides a kind of measuring devices for realizing above-mentioned measurement method.The present invention can be realized the fused data that the shooting of separate unit light-field camera single-point obtains model three-dimensional dimension and surface pressure distribution, compared to other pressure sensitive paints and three-dimensionalreconstruction photographing request, hence it is evident that the complexity for reducing system improves the efficiency of measurement.
Description
Technical field
The present invention relates to aerodynamic measurement technical fields, and in particular, to one kind is based on pressure sensitive paint and light-field camera
Size and surface pressure measurement method and apparatus.
Background technique
Pressure sensitive paint (PSP) is as a kind of contactless and high-resolution surface pressure measuring technique, from twentieth century eight
Since the ten's were suggested, it has been widely used in always in air stage combustion research.It is passed with traditional pressure gauge or pressure
Sensor can only obtain pressure data difference point by point, and pressure sensitive paint can disposably measure the pressure distribution on complex model surface.The skill
The oxygen quenching feature of fluorescent molecule is utilized in art, and under suitable shooting condition, measurement accuracy is theoretically limited only by and is used up
The precision of electric explorer.By using suitable pressure sensitive paint substrate and imaging device, static state can adapt to or comprising dynamic fluctuation
Pressure measurement.
Pressure sensitive paint technology, which is developed so far, to be constantly improve, but fixed by paint vehicle temperature sensitivity, model offset deformation, flashing
Error caused by the factors such as property and light degradation can not accomplish to completely eliminate.In addition to improving precision in low speeds flow and in high velocity stream
It is improved other than response frequency in dynamic, how to obtain the pressure distribution of a complex three-dimensional model overall surface is also in the field
Research emphasis.
In recent years, the development of optical field imaging provides a kind of potential polyphaser imaging for threedimensional model pressure sensitive paint measurement
Alternative solution.The set of Free propagation light in " light field " representation space, usually by five dimension parametric equationsDescribe, wherein L is the measurement of light radiation density, (x, y, z) andRespectively indicate light
Space and angle information.Five dimension light fields can be reduced to the four-dimension by two parallel sample planes, i.e. L=L (u, v, s, t),
In (u, v) and (s, t) be respectively light Yu the two planes intersecting point coordinate.In order to record four-dimensional light field, need in camera light
One piece of microlens array is placed at electric transducer the last period distance, if this distance is equal to the focal length of lenticule, obtained new camera
Structure is referred to as to defocus type light-field camera (Defocused Plenoptic Camera), is disambiguation, mentioned below
Light field or light-field camera all refer to the optical imaging system built in this structure basis.Spatially any light can
It is uniquely determined by it with camera main lens and the intersection point of lenticule plane.If remembering, main lens plane is (u, v), and lenticule is flat
Face is then (s, t).By the light of lenticule be considered as having after lenticule re-sampling the four-dimensional light field L of acquisition (u,
V, s, t) ability, light field original photo is done to certain processing, can obtain shooting object depth information.
Now measure complex geometry Aerodynamics Model three-dimensional dimension and pressure distribution be mostly by polyphaser at
The mode of picture is realized.The pressure sensitive paint technology of multi-angle of view formula to the installation of model and polyphaser, arrangement, calibrate and open up optics
The quantity of window is proposed very high requirement.These requirements test especially large tunnel experiment for aerodynamics
It is very unfavorable.
Summary of the invention
For the defects in the prior art, the size based on pressure sensitive paint and light-field camera that the object of the present invention is to provide a kind of
With surface pressure measurement method and apparatus.
The measurement method of the three-dimensional dimension and surface pressing based on pressure sensitive paint and light-field camera provided according to the present invention, packet
Containing following steps:
Picture obtaining step: the pressure signal light field picture and depth signal light field picture of model are obtained respectively；
Surface pressure distribution calculates step: model surface pressure-plotting is calculated from pressure signal light field picture；
Case depth distribution calculates step: model surface depth profile is calculated from depth signal light field picture；
Three-dimensional pressure is distributed generation step: the information and model surface depth profile of Fusion Model surface pressure distribution figure
Information, generate threedimensional model pressure-plotting.
Preferably, the picture obtaining step comprises the steps of:
Pressure signal light field picture obtaining step: wind-tunnel is closed operating condition and is opened under operating condition, is shot using light-field camera purple
The model for being coated with pressure sensitive paint of outer light source excitation, respectively obtains pressure signal light field picture, and be denoted as first pressure light field respectively
Picture, second pressure light field picture；
Depth signal light field picture obtaining step: wind-tunnel is closed under operating condition, is projected pattern using light-field camera shooting
Model.
Preferably, the surface pressure distribution calculates step and comprises the steps of:
Centre visual angle picture obtaining step: it takes out all micro- in first pressure light field picture and second pressure light field picture
The pixel of all taking-ups is pressed the position distribution split of lenticule, respectively obtains the first center by the corresponding pixel of mirror projection centre
Multi-perspective picture and the second centre visual angle picture；
Rotation translation correction step: the first centre visual angle picture and the second centre visual angle picture are rotated and is translated
Correction, the second centre visual angle picture after the first centre visual angle picture and correction after being rectified a deviation respectively；
Light intensity ratio chart piece obtaining step: the first centre visual angle picture after rectifying a deviation is as reference picture, after correction
The first centre visual angle picture respective pixel value and correction after the second centre visual angle picture respective pixel value do division, obtain light
Strong ratio picture；
Model surface calculation of pressure step: it is calculated based on light intensity ratio chart piece and obtains model surface pressure.
Preferably, in centre visual angle picture obtaining step, using pinhole imaging system principle, pass through blank under shooting minimum aperture
Obtain lenticule projection centre；
In rotation translation correction step, rotation translation parameters is obtained based on following formula:
W′on=T(Δx,Δy)RΔθWon
In formula: W 'onFor the picture matrix after rotation translation；T(Δx,Δy)For translation matrix；Δ x, Δ y are translation ginseng
Number；RΔθFor spin matrix；Δ θ is rotation parameter；WonThe picture matrix of operating condition is opened for wind-tunnel；(Δ θ, Δ x, Δ y) are rotation
Translation parameters；argminΔθ,Δx,ΔyΔ θ when () represents bracket Nei Daishi minimalization, Δ x, Δ y value；Sum () is to seek bracket
The algorithm of the sum of interior matrix element value；WoffThe picture matrix of operating condition is closed for wind-tunnel；× represent the element multiplication of corresponding position；
In light intensity ratio chart piece obtaining step, light intensity ratio chart piece passes through Woff./W′onIt obtains, wherein/representative corresponds to position
The element set is divided by；
In model surface calculation of pressure step, is calculated based on following formula and obtains model surface pressure:
In formula: I is the fluorescence intensity got off by cameras record；Ref is reference value, and choosing numerical value when wind-tunnel is closed is ginseng
Examine value；IrefFor with reference to fluorescence intensity；A1With A2It is the pressure sensitive paint coefficient of performance；A1(T) and A2It (T) is the pressure sensitive paint coefficient of performance
Function about temperature；P is surface pressure；PrefFor reference surface pressure.
Preferably, the case depth distribution calculates step and comprises the steps of:
Deep vision picture obtaining step: centre visual angle picture is carried out to depth signal light field picture and obtains operation, is obtained
Lenticule projection centre is symmetrical centre distribution, and size is the deep vision picture of a × a；
EPI slope exports step: the EPI slope k of each pixel in output deep vision pictureepi；
Depth calculation step: according to kepiCalculate the actual depth d on model.
Preferably, the EPI slope output step comprises the steps of:
Step S1: sub-pix translation, translation vector are done to all visual angles in addition to centre visual angleIt counts as follows
It calculates:
In formula: labelindFor the index number of current label；labeltotalFor the total number of labels of setting；labelind∈[0,
labeltotal] and labelindFor integer；labelstepFor the label step-length of setting；kconstFor the translation constant term of setting；
Vector for a non-central view position relative to centre visual angle position；
Step S2: one label of every translationind, the cost value of a × a displacement images collection is calculated, is calculated according to the following formula
Slope k of the pixel in EPI at (x, y) in centre visual angle pictureepi(x,y):
In formula:Label when representing bracket Nei Daishi minimalizationindValue；α is proportionality coefficient；CDIt is flat
Absolute value the sum of of the pictures compared to center picture pixel value difference after shifting；CGIt is pictures after translation compared to center picture ladder
Spend the sum of absolute difference.
Preferably, in depth calculation step, actual depth d is calculated according to the following formula:
In formula: K is number of pixels shared by the corresponding main lens size in unit visual angle；D be main lens light hole straight
Diameter；A is the microimage size of main lens；SpxFor the side length of single pixel；F is the focal length of main lens；fnFor the f- of main lens
Number,U is object distance；R be by the pixel number scaling of original image to view transformation image,OrWherein, the size of the picture at unit visual angle is m × n, and the size of original image is M × N.
Preferably, the value of u and K are sought using measurement calibration: repeatedly shooting calibration plate, every time before shooting, will be calibrated
Plate moves the distance, delta d of a setting along the direction for being parallel to camera primary optical axis；Obtain the k of characteristic point on calibration plateepi, in u
With in set interval, the residual values quadratic sum of u and the K expression formula of d under estimated value is sought with least square method near K estimated value
The value of S (i, j), u and K when to take S (i, j) be minimum value are match value:
In formula: KfinalFor the match value of K；ufinalFor the match value of u；() represents bracket Nei Daishi and takes pole
K when small valueiWith ujValue；KiFor near K estimated value in section i-th of K value；ujFor near u estimated value in section
The value of j-th of u；S is residual values quadratic sum；(i, j) is the coordinate position of characteristic point in set interval near u and K estimated value.
Preferably, using spline curve fitting, the model surface of discrete distribution is deep in three-dimensional pressure distribution generation step
Degree result is converted into continuously distributed by different cross section fitting；
The information of model surface pressure-plotting is coupled with the information of model surface depth profile by corresponding position, is obtained
Obtain threedimensional model pressure-plotting.
Above-mentioned three-dimensional dimension and surface pressing based on pressure sensitive paint and light-field camera is realized the present invention also provides a kind of
The measuring device of measurement method comprising tested model, ultraviolet source, light-field camera and projector only include a light field
Camera, the projector can be in tested model projection patterns.
Compared with prior art, the present invention have it is following the utility model has the advantages that
1, the present invention can be realized the shooting of separate unit light-field camera single-point and obtain model three-dimensional dimension and surface pressure distribution
Fused data, compared to other pressure sensitive paints and three-dimensionalreconstruction photographing request, hence it is evident that the complexity for reducing system improves measurement
Efficiency.
2, the present invention can realize the acquisition of single-point shooting formula threedimensional model pressure distribution under certain shooting condition, effectively
Existing three-dimensional measurement technology and incompatibility of the pressure sensitive paint technology in experimental facilities, experimentation are avoided, is subsequent into one
Walk simplified technology complexity, raising measurement efficiency opens a new road.
3, the present invention realizes measurement while to model three-dimensional dimension and surface pressure distribution using only a camera, can
To effectively improve wind-tunnel operational paradigm.
Detailed description of the invention
Upon reading the detailed description of non-limiting embodiments with reference to the following drawings, other feature of the invention,
Objects and advantages will become more apparent upon:
Fig. 1 is in the embodiment of the present invention for obtaining the device figure of model surface pressure；
Fig. 2 is in the embodiment of the present invention for obtaining the device figure of model surface depth；
Fig. 3 is the application example that the present invention is measured for a particular model；
Fig. 4 is the depth error Distribution value on application example model axis；
Fig. 5 is the measurement method stream of the three-dimensional dimension and surface pressing provided by the invention based on pressure sensitive paint and light-field camera
Cheng Tu；
It is shown in figure: tested model 1；Ultraviolet source 2；Light-field camera 3；Projector 4；Picture obtaining step 101；Surface pressure
Power distribution calculates step 102；Case depth distribution calculates step 103；Three-dimensional pressure is distributed generation step 104.
Specific embodiment
The present invention is described in detail combined with specific embodiments below.Following embodiment will be helpful to the technology of this field
Personnel further understand the present invention, but the invention is not limited in any way.It should be pointed out that the ordinary skill of this field
For personnel, without departing from the inventive concept of the premise, various modifications and improvements can be made.These belong to the present invention
Protection scope.
In the description of the present invention, it is to be understood that, term " on ", "lower", "front", "rear", "left", "right", " perpendicular
Directly ", the orientation or positional relationship of the instructions such as "horizontal", "top", "bottom", "inner", "outside" is orientation based on the figure or position
Relationship is set, is merely for convenience of description of the present invention and simplification of the description, rather than the device or element of indication or suggestion meaning are necessary
It with specific orientation, is constructed and operated in a specific orientation, therefore is not considered as limiting the invention.
As shown in figure 5, the measurement of the three-dimensional dimension and surface pressing provided by the invention based on pressure sensitive paint and light-field camera
Method comprising the steps of: picture obtaining step: the pressure signal light field picture and depth signal light field figure of model are obtained respectively
Piece；Surface pressure distribution calculates step: model surface pressure-plotting is calculated from pressure signal light field picture；Surface is deep
Degree distribution calculates step: model surface depth profile is calculated from depth signal light field picture；Three-dimensional pressure distribution life
At step: the information of Fusion Model surface pressure distribution figure and the information of model surface depth profile generate threedimensional model pressure
Power distribution map.
The picture obtaining step comprises the steps of: pressure signal light field picture obtaining step: wind-tunnel close operating condition with
It opens under operating condition, using the model for being coated with pressure sensitive paint of light-field camera shooting ultraviolet source excitation, respectively obtains pressure signal light
Field picture, and it is denoted as first pressure light field picture, second pressure light field picture respectively；Depth signal light field picture obtaining step:
Wind-tunnel is closed under operating condition, and the model of pattern is projected using light-field camera shooting.In embodiment, picture obtaining step is used and is based on
The pressure measurement means of pressure sensitive paint excitation intensity, 3 d light fields pressure sensitive paint technology are made of two parts.It is model surface first
Fluorescence light field image obtains and calculation of pressure, and followed by model surface 3 d light fields image obtains and depth reconstructs.Model is waited for
The region of survey is placed in the somewhere within focal plane, opens ultraviolet source, so that pressure sensitive paint is issued fluorescence by excitation, utilizes
Light-field camera come obtain wind-tunnel opening and closing when model surface fluorescent image.As shown in Figure 1,3 d light fields pressure sensitive paint technology is the same as two dimension
Pressure sensitive paint system is more similar, unique the difference is that the former is the tradition for replacing the latter to use using light-field camera when wind-tunnel is opened and closed
Camera obtains picture.Model surface 3 d light fields image, which is obtained, obtains no strict sequence with pressure information image.Such as
Shown in Fig. 2, ultraviolet source is closed, opens projector, the stain white background pattern for selecting density proper is projected on model table to be measured
Face, so that stain is uniformly distributed in honeycomb hexagon, the stain gross area accounts for about the 40% to 50% of total projection area.It does not move
The position of light-field camera, shooting obtain the model surface figure under this projection.
The surface pressure distribution calculates step and comprises the steps of: centre visual angle picture obtaining step: taking out the first pressure
Power light field picture pixel corresponding with lenticule projection centres all in second pressure light field picture, the pixel of all taking-ups is pressed
The position distribution split of lenticule respectively obtains the first centre visual angle picture and the second centre visual angle picture；Rotation translation correction
Step: the correction that the first centre visual angle picture and the second centre visual angle picture are rotated and translated, after being rectified a deviation respectively
The first centre visual angle picture and correction after the second centre visual angle picture；Light intensity ratio chart piece obtaining step: after correction
First centre visual angle picture is as reference picture, to the after the first centre visual angle picture respective pixel value and correction after correction
Two centre visual angle picture respective pixel values do division, obtain light intensity ratio chart piece；Model surface calculation of pressure step: it is based on light intensity
Ratio picture, which calculates, obtains model surface pressure.
In embodiment, before doing respective pixel division and obtaining light intensity scaled image, need to do light field original image
Pretreatment.The pretreated first step is the projection centre for obtaining each lenticule on camera photoelectric sensor.Uniformly by one piece
Blank be placed on camera before, aperture is adjusted to the picture that shooting after minimum obtains blank, using 9 × 9 Gaussian Profile to each
Bright spot is fitted, and calculates the lenticule projection centre coordinate of sub-pix.Using the coordinate at each center, can will thereafter pair
The pixel set answered artificially is encoded.It is micro- if the size of original image is M × N under conditions of length is as unit of pixel
The side length of the external square of circle where lens is A；The quantity of lenticule is X × Y.According to the four-dimension referred in background technique
The principle L=L (u, v, s, t) of optical field imaging, each pixel under lenticule are represented relative to the coordinate of its projection centre
One determining (u, v) value, and projection centre of the lenticule on pixel planes determines the value of (s, t).(u, v) value
Meaning can be regarded as light and pass through the different position of main lens, thus take out (u, v) value under all lenticules it is identical some
It is combined by arrangement rule of the lenticule center in photoelectric sensor plane, just can obtain a visual angle by pixel
Image, the case where not falling in lenticule projection centre position for actual picture pixel in anabolic process, used based on neighbour
The interpolation algorithm of nearly sampled point calculates the pixel value at the point.The size of some multi-perspective picture generated can be manually set, this
Place is set as m × n.For theoretically, for the optical field imaging system, the figure at all visual angles on A × a-quadrant inscribed circle can be obtained
Picture.For the model light field original image obtained under the conditions of wind-tunnel opening and closing, only takes the centre visual angle of the two to do subsequent processing, that is, use
The picture that picture element interpolation at lenticule projection centre obtains.
Model translation and rotation caused by pretreated second step needs to consider to open due to wind-tunnel.First by the area of model
Domain is marked off using Threshold segmentation come by background zero setting, if the picture matrix that wind-tunnel opens operating condition is Won, wind-tunnel switch close operating condition
Picture matrix be Woff.Deflection angle when appraising model is closed when wind-tunnel is opened relative to wind-tunnel, with anti-under the angle
To Two Dimensional Rotating matrix RθRotating model eliminates the angle difference of the two model；Translation distance is estimated again, introduces translation matrix
T(Δx,Δy), the model after rotating through is translated, if WonIn certain point coordinate beThen by translating postrotational coordinateTraverse WonModel translation is postrotational when obtaining wind-tunnel unlatching after upper all non-zero points is distributed as Won′.It is right
WoffAnd Won' corresponding position seek dot product, take the element of result to sum, then deflecting translation parameters, (Δ θ, Δ x, Δ y) reply should
With parameter of value when maximum, it may be assumed that
W′on=T(Δx,Δy)RΔθWon
In formula: W 'onFor the picture matrix after rotation translation；T(Δx,Δy)For translation matrix；Δ x, Δ y are translation ginseng
Number；RΔθFor spin matrix；Δ θ is rotation parameter；WonThe picture matrix of operating condition is opened for wind-tunnel；(Δ θ, Δ x, Δ y) are rotation
Translation parameters；argminΔθ,Δx,ΔyΔ θ when () represents bracket Nei Daishi minimalization, Δ x, Δ y value；Sum () is to seek bracket
The algorithm of the sum of interior matrix element value；WoffThe picture matrix of operating condition is closed for wind-tunnel；× represent the element multiplication of corresponding position.
After deflection translation parameters has been determined, light intensity scaled image is sought using the result after deflection, that is, passes through Woff./
W′onIt acquires, wherein the element of/represent corresponding position is divided by.
Based on the Stern-Volmer equation after improvement, operating condition and unlatching the two operating conditions of operating condition are closed by calculating wind-tunnel
The ratio of lower image corresponding position pixel value calculates three-dimensional in conjunction with the calibration equation and parameter to pressure sensitive paint under experimental temperature
The pressure of model surface is distributed:
In formula: I is the fluorescence intensity got off by cameras record；Ref is reference value, and choosing numerical value when wind-tunnel is closed is ginseng
Examine value；IrefFor with reference to fluorescence intensity；A1With A2It is the pressure sensitive paint coefficient of performance；A1(T) and A2It (T) is the pressure sensitive paint coefficient of performance
Function about temperature；P is surface pressure；PrefFor reference surface pressure.
Case depth distribution calculates step and comprises the steps of: deep vision picture obtaining step: to depth signal light field
Picture carries out centre visual angle picture and obtains operation, obtains lenticule projection centre as symmetrical centre distribution, size is the depth of a × a
Spend visual；EPI slope exports step: the EPI slope k of each pixel in output deep vision pictureepi, EPI
(Epipolar Plane Image) be pole geometric graph, EPI slope be same object with visual angle change one kind of displacement
Measurement；Depth calculation step: according to kepiCalculate the actual depth d on model.
In embodiment, with above-mentioned tonogram as treatment process is similar, before handling depth information, estimate for successive depths
The demand of calculating method, the visual angle for needing to take out a part in all visual angles are subject to using these viewing angle distributions are with lenticule
Projection centre be symmetrical centre, size be (a < A, and a is integer) on the square of a × a.It is deep by these pictures cooperations
After spending the input quantity of algorithm for estimating, the result formats of estimation of Depth are to output using centre visual angle picture as template, Centered Graphs
The EPI slope k of on piece every bitepi, the meaning of this slope can regard the displacement pixel number of per unit visual angle point as, be located at pair
It takes just, otherwise takes negative within focal plane.The depth estimation algorithm main body divides the following steps:
Step S1: sub-pix translation, translation vector are done to all visual angles in addition to centre visual angle Wherein labelindFor the index number of current label, labelind∈[0,labeltotal] and be
Integer；labeltotalIt is the total number of labels being manually set, generally takes 60-100；labelstepIt is the label step-length being manually set；
kconstIt is the translation constant term being manually set, the purpose is to make final involved translation distance by depth occupied by model
While degree range is included, and it is unlikely to too many beyond the range；It is the view position relative to centre visual angle position
Vector, for centre visual angle,It can be regarded as zero.
Step S2: one label of every translationind, calculate the cost value (Cost volume) of a × a displacement images collection, cost
The size of value is divided into two parts: first part is set of pixels at pictures (x, y) compared to pixel value difference at center picture (x, y)
Absolute value and CD, second part is gradient at pictures (x, y) compared to gradient difference value absolute value at center picture (x, y)
And CG.The two is α C by the cost value that proportionality coefficient α couples finallyD+(1-α)CG, α ∈ [0,1], α generally takes 0.5.
To labelindLower center image all pixels seek cost value, and to all labelindTraverse, obtain m × n ×
labeltotalMulti-tag cost collection.For kepi(x,y), i.e., slope of the pixel in EPI at (x, y) in centre visual angle picture
Have:
In formula:Label when representing bracket Nei Daishi minimalizationindValue；α is proportionality coefficient；CDIt is flat
Absolute value the sum of of the pictures compared to center picture pixel value difference after shifting；CGIt is pictures after translation compared to center picture ladder
Spend the sum of absolute difference.
Using the thin-lens equation and the design feature of light-field camera, k can be releasedepiBetween actual depth d
Relationship is
In formula: K is number of pixels shared by the corresponding main lens size in unit visual angle；D be main lens light hole straight
Diameter；A is the microimage size of main lens；SpxFor the side length of single pixel；F is the focal length of main lens；fnFor the f- of main lens
Number,U is object distance；R be by the pixel number scaling of original image to view transformation image,OrWherein, the size of the picture at unit visual angle is m × n, and the size of original image is M × N.For theoreticallyWithTwo
Person should be equal, but due in practice and not all camera photoelectric sensor can be covered by lenticule, also or edge
Lenticule quality defect, cause using marginal portion second-rate in the middle original image for needing to remove M × N, if removal
Image size behind edge is M ' × N ', then actual image scaling size is answered are as follows:
Or
In above formula, F and fnIt can accurately be read from the parameter of main lens, SpxIt, also can be from camera as the size of pixel
It is accurately read in manufacturing parameter.Object distance u value is unknown in formula, and the value that lenticule projects the external square side length A of spot can be by estimating
The diameter of lenticule projection round spot under the aperture size is calculated to obtain, subsequent metric is calibrated can be by this estimated value meter in calculating
The K got seeks the optimum solution of u and K as initial value.
The purpose of measurement calibration is to seek accurate u and A value, and way is that multiple shooting is easily obtained kepiCalibration plate, and
Calculate the k of certain characteristic points on calibration plateepi, every time before shooting, calibration plate is moved along the direction for being parallel to camera primary optical axis
Move a known distance, delta d.The pattern of calibration plate must be conducive to kepiAccurate acquisition, the present invention used in pattern be normal
Black and white checkerboard fashion used in the camera calibrated seen.Moving distance Δ d is freely set by high-precision linear displacement platform, initially
Position is generally set to certain slightly far from focal plane, i.e.,It is slightly less than zero, final position generally artificially adjustsIf the sum of shooting is G, then the total distance moved is (G-1) Δ d, in the estimated value K of KestiValue
Some neighbouring section such as (95%Kesti, 105%Kesti) in take Ki, solve about corresponding estimation object distance uestiEquation:
In the estimated value u of uestiSome section such as (95%u near valueesti, 105%uesti) in take uj, according to known
The different k of G groupepi, (K is sought using least square methodi,uj) under parameterResidual sum of squares (RSS), be denoted as S
(i, j) it is closest with true value can to regard fitting result as when residual sum of squares (RSS) minimum, it may be assumed that
In formula: KfinalFor the match value of K；ufinalFor the match value of u；() represents bracket Nei Daishi and takes pole
K when small valueiWith ujValue；KiFor near K estimated value in section i-th of K value；ujFor near u estimated value in section
The value of j-th of u；S is residual values quadratic sum；(i, j) is the coordinate position of characteristic point in set interval near u and K estimated value.
Three-dimensional pressure is distributed in generation step, using spline curve fitting, by the model surface depth results of discrete distribution
Be converted by different cross section fitting it is continuously distributed, by the information of model surface pressure-plotting and model surface depth profile
Information is coupled by corresponding position, obtains threedimensional model pressure-plotting.
Due to the discreteness of label, depth distribution cannot be well matched with curved surface, take the spline curve in Matlab quasi-
Close, by the model surface depth results of discrete distribution by different cross section fitting be converted into it is continuously distributed, improve due to discrete tags
Presence and reduced sampling precision.Finally pressure is merged with the depth data after post-processing can obtain final three-dimensional
Model pressure distribution results, as shown in Figure 3, corresponding point, used in Matching Model involved in fusion process for specific application example
Method it is similar with above-mentioned mode.
Fig. 4 gives depth calculations described in the embodiment of the present invention and pair in true model size in a model axis
Ratio error distribution map, wherein the direction of X-axis is the direction of the top meaning of model.As can be seen that in the biggish feelings of model sectional area
Under condition, the error of estimation of Depth can be efficiently controlled within ± 1mm, top close to model partially due to sectional area becomes
It is small, cause model surface curvature to increase considerably, since global camera resolution is definite value, therefore sectional area becomes smaller and causes reality
The decline of resolution capability, so that depth calculations deviation true value is more.
But generally, the present invention can realize single-point shooting formula threedimensional model pressure distribution under certain shooting condition
It obtains, effectively prevents existing three-dimensional measurement technology and incompatibility of the pressure sensitive paint technology in experimental facilities, experimentation, be
It is subsequent be further simplified technology complexity, improve measurement efficiency open a new road.
The present invention provides a kind of above-mentioned three-dimensional dimension based on pressure sensitive paint and light-field camera and surface pressings realized
The measuring device of measurement method comprising tested model, ultraviolet source, light-field camera and projector, and only includes a light field
Camera, the projector can be in tested model projection patterns.In pressure signal light field picture obtaining step, ultraviolet light is opened
Source is closed projector, and is taken pictures using light-field camera；In depth signal light field picture obtaining step, ultraviolet source is closed, is opened
Projector projects on tested model, and is taken pictures using light-field camera.
Specific embodiments of the present invention are described above.It is to be appreciated that the invention is not limited to above-mentioned
Particular implementation, those skilled in the art can make various deformations or amendments within the scope of the claims, this not shadow
Ring substantive content of the invention.In the absence of conflict, the feature in embodiments herein and embodiment can any phase
Mutually combination.
Claims (8)
1. a kind of measurement method of three-dimensional dimension and surface pressing based on pressure sensitive paint and light-field camera, which is characterized in that include
Following steps:
Picture obtaining step: the pressure signal light field picture and depth signal light field picture of model are obtained respectively；
Surface pressure distribution calculates step: model surface pressure-plotting is calculated from pressure signal light field picture；
Case depth distribution calculates step: model surface depth profile is calculated from depth signal light field picture；
Three-dimensional pressure is distributed generation step: the information of Fusion Model surface pressure distribution figure and the letter of model surface depth profile
Breath generates threedimensional model pressure-plotting；
The picture obtaining step comprises the steps of:
Pressure signal light field picture obtaining step: wind-tunnel is closed operating condition and is opened under operating condition, shoots ultraviolet light using light-field camera
The model for being coated with pressure sensitive paint of source excitation respectively obtains pressure signal light field picture, and be denoted as respectively first pressure light field picture,
Second pressure light field picture；
Depth signal light field picture obtaining step: wind-tunnel is closed under operating condition, and the model of pattern is projected using light-field camera shooting；
The surface pressure distribution calculates step and comprises the steps of:
Centre visual angle picture obtaining step: all lenticules in first pressure light field picture and second pressure light field picture are taken out and are thrown
The pixel of all taking-ups is pressed the position distribution split of lenticule, respectively obtains the first centre visual angle by the corresponding pixel in shadow center
Picture and the second centre visual angle picture；
Rotation translation correction step: the first centre visual angle picture is rotated with the second centre visual angle picture and what is translated entangles
Partially, the second centre visual angle picture after the first centre visual angle picture and correction after being rectified a deviation respectively；
Light intensity ratio chart piece obtaining step: the first centre visual angle picture after rectifying a deviation is as reference picture, to the after correction
The second centre visual angle picture respective pixel value after one centre visual angle picture respective pixel value and correction does division, obtains beam intensity ratio
Example diagram piece；
Model surface calculation of pressure step: it is calculated based on light intensity ratio chart piece and obtains model surface pressure.
2. the measurement method of the three-dimensional dimension and surface pressing according to claim 1 based on pressure sensitive paint and light-field camera,
It is characterized in that, using pinhole imaging system principle, being obtained by blank under shooting minimum aperture in centre visual angle picture obtaining step
Lenticule projection centre；
In rotation translation correction step, rotation translation parameters is obtained based on following formula:
W′on=T(Δ x, Δ y)RΔθWon
In formula: W 'onFor the picture matrix after rotation translation；T(Δ x, Δ y)For translation matrix；Δ x, Δ y are translation parameters；RΔθ
For spin matrix；Δ θ is rotation parameter；WonThe picture matrix of operating condition is opened for wind-tunnel；(Δ θ, Δ x, Δ y) are rotation translation ginseng
Number；argminΔ θ, Δ x, Δ yΔ θ when () represents bracket Nei Daishi minimalization, Δ x, Δ y value；Sum () is to seek matrix in bracket
The algorithm of the sum of element value；WoffThe picture matrix of operating condition is closed for wind-tunnel；× represent the element multiplication of corresponding position；
In light intensity ratio chart piece obtaining step, light intensity ratio chart piece passes through Woff./W′onIt obtains, wherein/represent corresponding position
Element is divided by；
In model surface calculation of pressure step, is calculated based on following formula and obtains model surface pressure:
In formula: I is the fluorescence intensity got off by cameras record；Ref is reference value, and choosing numerical value when wind-tunnel is closed is reference
Value；IrefFor with reference to fluorescence intensity；A1With A2It is the pressure sensitive paint coefficient of performance；A1(T) and A2It (T) is that the pressure sensitive paint coefficient of performance closes
In the function of temperature；P is surface pressure；PrefFor reference surface pressure.
3. the measurement method of the three-dimensional dimension and surface pressing according to claim 1 based on pressure sensitive paint and light-field camera,
It is characterized in that, the case depth distribution calculates step and comprises the steps of:
Deep vision picture obtaining step: centre visual angle picture is carried out to depth signal light field picture and obtains operation, is obtained micro-
Mirror projection centre is symmetrical centre distribution, and size is the deep vision picture of a × a；
EPI slope exports step: the EPI slope k of each pixel in output deep vision pictureepi；
Depth calculation step: according to kepiCalculate the actual depth d on model.
4. the measurement method of the three-dimensional dimension and surface pressing according to claim 3 based on pressure sensitive paint and light-field camera,
It is characterized in that, the EPI slope output step comprises the steps of:
Step S1: sub-pix translation, translation vector are done to all visual angles in addition to centre visual angleIt calculates as follows:
In formula: labelindFor the index number of current label；labeltotalFor the total number of labels of setting；labelind∈ [0,
labeltotal] and labelindFor integer；labelstepFor the label step-length of setting；kconstFor the translation constant term of setting；
Vector for a non-central view position relative to centre visual angle position；
Step S2: one label of every translationind, the cost value of a × a displacement images collection is calculated, calculates center according to the following formula
Slope k of the pixel in EPI at (x, y) in multi-perspective pictureEpi (x, y):
In formula:Label when representing bracket Nei Daishi minimalizationindValue；α is proportionality coefficient；CDAfter translation
Absolute value the sum of of the pictures compared to center picture pixel value difference；CGIt is pictures after translation compared to center picture gradient difference
It is worth the sum of absolute value.
5. the measurement method of the three-dimensional dimension and surface pressing according to claim 4 based on pressure sensitive paint and light-field camera,
It is characterized in that, calculating actual depth d according to the following formula in depth calculation step:
In formula: K is number of pixels shared by the corresponding main lens size in unit visual angle；D is the clear aperture diameter of main lens；A
For the microimage size of main lens；SpxFor the side length of single pixel；F is the focal length of main lens；fnFor the f-number of main lens,U is object distance；R be by the pixel number scaling of original image to view transformation image,Or
Wherein, the size of the picture at unit visual angle is m × n, and the size of original image is M × N.
6. the measurement method of the three-dimensional dimension and surface pressing according to claim 5 based on pressure sensitive paint and light-field camera,
It is characterized in that, seeking the value of u and K using measurement calibration: calibration plate is repeatedly shot, every time before shooting, by calibration plate edge
Be parallel to camera primary optical axis the mobile setting in direction distance, delta d；Obtain the k of characteristic point on calibration plateepi, in u and K
In set interval, the residual values quadratic sum S of u and the K expression formula of d under estimated value is nearby sought with least square method for estimated value
The value of (i, j), u and K when to take S (i, j) be minimum value are match value:
In formula: KfinalFor the match value of K；ufinalFor the match value of u；() represents bracket Nei Daishi minimalization
When KiWith ujValue；KiFor near K estimated value in section i-th of K value；ujFor the jth in section near u estimated value
The value of a u；S is residual values quadratic sum；(i, j) is the coordinate position of characteristic point in set interval near u and K estimated value.
7. the measurement method of the three-dimensional dimension and surface pressing according to claim 1 based on pressure sensitive paint and light-field camera,
It is characterized in that, in three-dimensional pressure distribution generation step, using spline curve fitting, by the model surface depth knot of discrete distribution
Fruit is converted into continuously distributed by different cross section fitting；
The information of model surface pressure-plotting is coupled with the information of model surface depth profile by corresponding position, obtains three
Dimension module pressure-plotting.
8. a kind of three-dimensional dimension realized based on pressure sensitive paint and light-field camera described in any one of claims 1 to 7 and surface
The measuring device of the measurement method of pressure includes tested model, ultraviolet source, light-field camera and projector, which is characterized in that
It only include a light-field camera, the projector can be in tested model projection pattern.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810041152.4A CN108362469B (en) | 2018-01-16 | 2018-01-16 | Size and surface pressure measurement method and apparatus based on pressure sensitive paint and light-field camera |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810041152.4A CN108362469B (en) | 2018-01-16 | 2018-01-16 | Size and surface pressure measurement method and apparatus based on pressure sensitive paint and light-field camera |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108362469A CN108362469A (en) | 2018-08-03 |
| CN108362469B true CN108362469B (en) | 2019-11-01 |
Family
ID=63006390
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810041152.4A Active CN108362469B (en) | 2018-01-16 | 2018-01-16 | Size and surface pressure measurement method and apparatus based on pressure sensitive paint and light-field camera |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108362469B (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111017241B (en) * | 2019-12-19 | 2023-05-23 | 中国航空工业集团公司西安飞机设计研究所 | Wing flow field measuring device and method of double-fuselage unmanned aerial vehicle |
| CN111174958B (en) * | 2020-01-03 | 2021-09-07 | 西北工业大学 | Rotor blade surface universe dynamic pressure measuring device and method based on phase locking method |
| CN111458101A (en) * | 2020-03-12 | 2020-07-28 | 中国空气动力研究与发展中心低速空气动力研究所 | Method for measuring surface pulsating pressure of wind tunnel fixed wing model |
| CN112750156B (en) * | 2020-03-16 | 2022-09-09 | 奕目(上海)科技有限公司 | Light field imaging system, processing method and device |
| CN112393808B (en) * | 2020-11-23 | 2021-12-17 | 南通嘉骏信息科技有限公司 | Temperature compensation method and system for thermal camera |
| CN112268684B (en) * | 2020-12-14 | 2021-03-19 | 中国空气动力研究与发展中心低速空气动力研究所 | Variable azimuth angle surface pressure measuring system and method for low-speed wind tunnel rotor model |
| CN114062712B (en) * | 2021-09-29 | 2022-09-06 | 东南大学 | Single-optical-field-imaging-based synthetic aperture particle image speed measurement method and device |
| CN113834625B (en) * | 2021-10-13 | 2022-02-25 | 中国空气动力研究与发展中心低速空气动力研究所 | Aircraft model surface pressure measuring method and system |
| CN114441090B (en) * | 2022-04-11 | 2022-06-17 | 中国空气动力研究与发展中心高速空气动力研究所 | Quick response pressure-sensitive paint temperature effect correction method |
| CN114608784B (en) * | 2022-05-10 | 2022-07-19 | 中国空气动力研究与发展中心高速空气动力研究所 | Method for obtaining dynamic running pressure matching point of jet flow in jet wind tunnel through ultrasonic velocity jet flow |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5612492A (en) * | 1995-06-07 | 1997-03-18 | Mcdonnell Douglas Corporation | Formulations and method of use of pressure sensitive paint |
| US5731995A (en) * | 1996-04-12 | 1998-03-24 | Mc Donnell Douglas Corp | Method for determining pressure |
| CN203365103U (en) * | 2013-05-13 | 2013-12-25 | 中国航空工业集团公司沈阳空气动力研究所 | Measuring apparatus for fluorescent oil flow friction force filed |
| CN106768822A (en) * | 2017-02-07 | 2017-05-31 | 中国航天空气动力技术研究院 | A kind of flow field boundary layer shear stress measuring method |
| CN107560769A (en) * | 2017-08-23 | 2018-01-09 | 上海交通大学 | A kind of whole audience pressure testing system based on thin layer area source and pressure sensitive paint |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5231898B2 (en) * | 2008-08-27 | 2013-07-10 | 株式会社ミツバ | Pressure measuring device, pressure measuring method, and program for executing the same |
-
2018
- 2018-01-16 CN CN201810041152.4A patent/CN108362469B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5612492A (en) * | 1995-06-07 | 1997-03-18 | Mcdonnell Douglas Corporation | Formulations and method of use of pressure sensitive paint |
| US5731995A (en) * | 1996-04-12 | 1998-03-24 | Mc Donnell Douglas Corp | Method for determining pressure |
| CN203365103U (en) * | 2013-05-13 | 2013-12-25 | 中国航空工业集团公司沈阳空气动力研究所 | Measuring apparatus for fluorescent oil flow friction force filed |
| CN106768822A (en) * | 2017-02-07 | 2017-05-31 | 中国航天空气动力技术研究院 | A kind of flow field boundary layer shear stress measuring method |
| CN107560769A (en) * | 2017-08-23 | 2018-01-09 | 上海交通大学 | A kind of whole audience pressure testing system based on thin layer area source and pressure sensitive paint |
Non-Patent Citations (4)
| Title |
|---|
| 2.4m跨声速风洞压敏漆测量系统研制与应用研究;熊健等;《实验流体力学》;20160630;第30卷(第3期);第76-84页 * |
| Accurate Depth Map Estimation from a Lenslet Light Field Camera;Hae-Gon Jeon等;《CVPR2015》;20151231;第1547-1555页 * |
| Pressure sensitive paint systems for pressure distribution measurements in wind tunnels and turbomachines;R H Engler等;《Measurement Science and Technology》;20001231;第1077–1085页 * |
| 光场单相机三维流场测试技术;丁俊飞等;《实验流体力学》;20161231;第30卷(第6期);第51-58页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108362469A (en) | 2018-08-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108362469B (en) | Size and surface pressure measurement method and apparatus based on pressure sensitive paint and light-field camera | |
| Luhmann et al. | Sensor modelling and camera calibration for close-range photogrammetry | |
| CN109859272B (en) | Automatic focusing binocular camera calibration method and device | |
| CN105716542B (en) | A kind of three-dimensional data joining method based on flexible characteristic point | |
| CN106772417B (en) | A kind of multiple dimensioned infrared spectrum pattern measurement method and system of moving-target various dimensions | |
| CN101373135B (en) | Method and apparatus for measuring three-dimensional curved surface based on instantaneous accidental light irradiation | |
| CN109767476A (en) | A kind of calibration of auto-focusing binocular camera and depth computing method | |
| CN109166154A (en) | Light-field camera calibration method for light field three dimensional particles image reconstruction | |
| CN107610102A (en) | A kind of Displacement measuring method based on Tikhonov regularizations | |
| CN105043720B (en) | The measuring method of infrared fileter refractive index based on single camera | |
| CN105092607A (en) | Method for evaluating surface defects of spherical optical components | |
| CN110044262B (en) | Non-contact precision measuring instrument based on image super-resolution reconstruction and measuring method | |
| Zhang et al. | Accuracy improvement in laser stripe extraction for large-scale triangulation scanning measurement system | |
| CN110514392A (en) | Temperature deformation measuring system and method based on wide-angle lens and image distortion correction | |
| CN109325927A (en) | Industrial camera photography measurement image luminance compensation method | |
| Burke et al. | Deflectometry for specular surfaces: an overview | |
| CN109974618A (en) | The overall calibration method of multisensor vision measurement system | |
| CN110836634B (en) | Four-quadrant detector calibration method capable of adapting to various light beams | |
| CN108007382B (en) | Surface shape measurement device and method based on Structured Illumination | |
| CN109242909A (en) | A kind of line-scan digital camera calibration algorithm towards high-precision two-dimensional dimensional measurement | |
| CN109754413A (en) | A kind of Feisuo type dynamic interferometer bar graph method for registering | |
| CN116907380A (en) | Accurate alignment method and system for measured mirror of point diffraction interferometer based on image information | |
| CN109064517B (en) | Optical axis perpendicularity adjusting method and device | |
| CN108007387B (en) | Surface shape measurement device and method based on Structured Illumination | |
| CN201277864Y (en) | Inner orientation element and distortion test instrument |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20211101 Address after: 200240 No. 800, Dongchuan Road, Shanghai, Minhang District Patentee after: Shi Shengxian Address before: 200240 No. 800, Dongchuan Road, Shanghai, Minhang District Patentee before: SHANGHAI JIAO TONG University |
|
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20211223 Address after: 201109 room 1206, building 1, No. 951, Jianchuan Road, Minhang District, Shanghai Patentee after: Yimu (Shanghai) Technology Co.,Ltd. Address before: 200240 No. 800, Dongchuan Road, Shanghai, Minhang District Patentee before: Shi Shengxian |
|
| CP03 | Change of name, title or address | ||
| CP03 | Change of name, title or address |
Address after: Room 102, 1st Floor, Building 98, No. 1441 Humin Road, Minhang District, Shanghai, 2019; Room 302, 3rd Floor, Building 98; Room 402, 4th Floor, Building 98 Patentee after: Yimu (Shanghai) Technology Co.,Ltd. Address before: 201109 room 1206, building 1, No. 951, Jianchuan Road, Minhang District, Shanghai Patentee before: Yimu (Shanghai) Technology Co.,Ltd. |