CN105405144B - Extraterrestrial target OCS quick calculation methods based on OpenGL dual picks - Google Patents
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T7/00—Image analysis
- G06T7/0002—Inspection of images, e.g. flaw detection
- G06T7/0004—Industrial image inspection
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T17/00—Three dimensional [3D] modelling, e.g. data description of 3D objects
- G06T17/20—Finite element generation, e.g. wire-frame surface description, tesselation
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T17/00—Three dimensional [3D] modelling, e.g. data description of 3D objects
- G06T17/20—Finite element generation, e.g. wire-frame surface description, tesselation
- G06T17/205—Re-meshing
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T2207/00—Indexing scheme for image analysis or image enhancement
- G06T2207/30—Subject of image; Context of image processing
- G06T2207/30232—Surveillance
Abstract
The present invention discloses a kind of extraterrestrial target OCS quick calculation methods based on OpenGL dual picks, including Step 1: extraterrestrial target is modeled；Step 2: parse threedimensional model and name each bin；Step 3: rendering model, visible bin pickup is carried out according to detector orientation to model, illumination bin pickup is carried out to model according to light source azimuth, obtains two bin set；Step 4: occuring simultaneously to the conjunction of above-mentioned two bin collection, the visible illumination bin of detector is obtained；Step 5: calculating the OCS values of each bin in the common factor obtained, and then calculate the OCS values of extraterrestrial target.The problem of efficiency is low when the present invention calculates extraterrestrial target OCS for current finite element method, function, quick obtaining visible face metamessage, to calculate the OCS values of target are picked up using OpenGL bin.This method not only avoid cumbersome elimination of hidden, can also obtain the details such as material, the summit of each bin, can quickly calculate the complex spatial object OCS being made up of various material.
Description
Technical field
The present invention relates to a kind of extraterrestrial target OCS (optical cross-section area, optical cross section) quick meter
Calculation method, belong to Space Target Surveillance technical field, for extraterrestrial target OCS quick calculating, help to carry out extraterrestrial target
The work such as Optical characteristics and Space object identification.
Background technology
Extraterrestrial target refers to the spacecraft and space junk in cosmic space operation.The OCS of extraterrestrial target is its important category
Property, pair determination Space Target Surveillance scheme, development target characteristics analysis and target identification are significant, to extraterrestrial target
OCS numerical computations are always the study hotspot in Space Target Surveillance field.
Extraterrestrial target optical cross-section area OCS definition is：
OCS=∫Afr(θi,θr)cosθicosθrdA (1)
For the small patches with area dA, its normal vector isBy the Unit Vector at model geometric center to the sun
Measure and beUnit vector by model geometric center to detector isThen θiForWithAngle and satisfaction
θrForWithAngle and satisfactionWherein ' ' is dot product；fr(θi,θr) it is BRDF (Bi-
Directional Reflectance Distribution Function, bidirectional reflectance distribution function) functional value, for anti-
Lambert's body target that rate is ρ is penetrated, it is respectively identical to BRDF values, i.e. fr(θi,θr)=ρ/π, BRDF numerical value corresponding to unlike material
It is different.For extraterrestrial target optical observation, the brightness of target is generally represented with magnitude, and magnitude again can be by the OCS of target
Value reckoning obtains, therefore also turns into measurement object brightness in the approximately uniform terrestrial space of intensity of illumination, the OCS of extraterrestrial target
Determinant attribute.From formula (1), the OCS of extraterrestrial target is only relevant with target materials, shape, incidence and the angle of emergence, and with detection
Device distance and performance parameter are unrelated, have wider purposes.
The limit of integration of above formula is the visible illuminating area of detector (effective bin), the part bin be light irradiate and
It is simultaneously visible for detector.For extraterrestrial target, incident sunshine can be considered the directional light of single direction, including the earth is anti-
Other light penetrated including light can be ignored.
In the existing computational methods to extraterrestrial target OCS, analytic method and FInite Element can be largely classified into.Analytic method is to use
Analytical expression describes the OCS numerical value in each angle, and precision is higher but is only applicable to the object of simple geometric shape, as flat board,
Spheroid, cube, cylinder, circular cone etc., often goal hypothesis is the solid of given shape in engineering, and then estimated using analytic method
Its OCS value is counted, evaluated error is larger.
Finite element rule is that object module is split as to large number of small patches, determines the visible illumination bin of detector
The OCS values of each bin are calculated afterwards, and most at last all bin OCS are cumulative to obtain the OCS values of target.Wherein, to effective bin (both
By illumination again it is visible by detector) analysis be FInite Element key technology.At present, the main method of effective bin is analyzed such as
Under：
Target is split as many small bins first, by the file of certain format, such as summit file, bin topology text
Apex coordinate, normal vector and representative material type of each small patches of the records such as part etc..Next need according to bin
Normal vector, incident sunshine direction vector and observed direction vector judge whether bin is visible, find out effective bin, this mistake
Journey is also referred to as primary occlusion judgement.On this basis, mutual screening of these small patches in illumination and observed direction is also judged
Gear relation, the small patches blocked by other bins are weeded out, this judgement is referred to as secondary shadowing, also referred to as target
Elimination of hidden.The deterministic process mutually blocked between bin is complicated and operand is huge, and its cycle criterion number is N2(N is face
First quantity), for a fairly large number of complex spatial object of bin, elimination of hidden is time-consuming longer.Simultaneously as shadowing be with
Bin center is according to what is carried out, certain error be present, reduces the method for this error and only increases bin quantity, this enters again
One step adds operand.If reducing bin quantity, increase bin area, between bin mutually the analytical error of hiding relation with
And will be significantly increased with the difference of realistic model, OCS computational accuracies reduce, and this contradiction, which turns into, restricts Finite element arithmetic sky
Between target OCS bottleneck problem.
Currently, in the extraterrestrial target OCS computational methods based on finite element theory, there is also the blanking side based on OpenGL
Method, this method read the pixel value after projection, and then extrapolate model by will realize elimination of hidden on model projection to screen
Flat-profile view and material situation.This method only for single material target, when simultaneously various material be present when, this method
No longer it is applicable.2010, in the STK 9.2.1 of AGI companies of U.S. issue, issued photoelectricity infrared module EOIR, the module by
U.S. space dynamic experiment room is developed, and can calculate the OCS values of extraterrestrial target.But the module is equally only applicable to single material
Model, applicability is limited.Technology proposed by the present invention aims to solve the problem that conventional finite element method elimination of hidden process is cumbersome, utilizes
The problems such as OpenGL can not handle various material target when reading pixel.
The content of the invention
The invention provides a kind of extraterrestrial target OCS quick calculation methods based on OpenGL dual picks, pass through
OpenGL pickup function, extraterrestrial target model is picked up respectively and in direction of illumination and the visible bin of detector direction and takes its friendship
Collection (i.e. significant surface member set), realizes the extraction to significant surface metamessage, and binding model parsing data and BRDF data calculate every
The OCS values of the individual effectively OCS values of bin and the acquisition target that finally adds up.The present invention is entered by OpenGL to Computer graphics hardware
Row operation, completion model is shown and the pickup of effective bin, not only can quick and precisely complete elimination of hidden, moreover it is possible to fully obtain
Significant surface metamessage including summit, material, improve the ability for calculating more material target OCS.
The purpose of the present invention implements by the following technical programs：
Extraterrestrial target OCS quick calculation methods based on OpenGL dual picks, including：
Step 1: extraterrestrial target is modeled using 3 d modeling software；
Step 2: parse threedimensional model and name each bin；
Step 3: using OpenGL rendering models, visible bin pickup is carried out to model according to detector orientation, according to light
Source orientation carries out illumination bin pickup to model, obtains two bin set；
Step 4: occuring simultaneously to the bin collection conjunction picked up twice in step 3, the visible illumination bin of detector is obtained；
Step 5: calculating the OCS values of each bin in the common factor obtained, all bin OCS that add up are worth to extraterrestrial target
OCS values.
It is described that extraterrestrial target is modeled using 3 d modeling software in step 1, including：Using 3 d modeling software to sky
Between target be modeled, model is divided into several Triangular object models, and retain the information of each bin, file is preserved into .3ds
Form.
The 3 d modeling software is Creator or 3DMAX；And/or
The information for retaining each bin, including retain the material and vertex information of each bin.
In step 2, the parsing threedimensional model simultaneously names each bin, including：Model file in analyzing step one,
Named to each Triangular object model parsed and record its summit, material information；
In step 3, it is also necessary to open OpenGL depth buffers and depth test, object module is being drawn based on OpenGL
Mutual hiding relation between Shi Tixian bins.
In step 3, when carrying out visible bin pickup, the observation visual angle to object module, observation visual angle are set twice
Determined by the actual illumination of extraterrestrial target and observation angle；And/or
Described pickup is the method that OpenGL obtains designated area bin information, pickup scope be whole drawing window with
Ensure to cover model region；And/or
It is described according to light source azimuth to model carry out illumination bin pickup, based on the extraterrestrial target run in track only by
The illumination of the sun.
In step 4, the visible illumination bin of detector that obtains is as the effective bin for calculating whole model OCS, ginseng
Calculated with follow-up OCS.
In step 5, the OCS values of each bin in the common factor of acquisition are calculated, including according to each bin vertex information computational chart
Face normal vector and bin area, its OCS is calculated with reference to each bin material.
When calculating the single effectively OCS of bin, calculate area, normal vector used in OCS and be all from solving in step 2
The data of analysis；The bin Material Name parsed according to step 2, in conventional extraterrestrial target Facing material BRDF, (bidirectional reflectance is distributed
Function) the BRDF parameters of the material are obtained in database；The OCS values of the bin are calculated with reference to above-mentioned parameter；And/or
Preferably, the conventional extraterrestrial target Facing material BRDF databases, to store conventional extraterrestrial target surface material
The BRDF parameters of matter, the database can be measured by BRDF measuring apparatus and obtain initial data, and then can calculate Phong moulds
The parameter value of the BRDF models such as type, five parameter semiempirical statistical models.For lambert's body target, can be resolved according to its reflectivity
BRDF。
The OCS values for calculating extraterrestrial target, refer on the basis of each effectively bin OCS calculating, will be all effective
Bin OCS values are cumulative to obtain the OCS values of whole extraterrestrial target model.
The problem of efficiency is low when the present invention calculates extraterrestrial target OCS for current finite element method, utilizes OpenGL face
Member pickup function, quick obtaining visible face metamessage, to calculate the OCS values of target.This method not only avoid cumbersome blanking
Processing, can also obtain the details such as material, the summit of each bin, can quickly calculate and be answered by what various material was formed
Miscellaneous extraterrestrial target OCS.
Brief description of the drawings
The present invention is described in further detail below according to drawings and examples.
Fig. 1 is KH-12 satellites threedimensional model and its element attribute schematic diagram, wherein, Fig. 1 a are right using Creator 2.6
The result that KH-12 satellites are modeled；Fig. 1 b are KH-12 satellite threedimensional model element attributes.
Fig. 2 is simple cylinder threedimensional model and its element attribute schematic diagram, wherein, Fig. 2 a are simple cylinder three-dimensional moulds
Type；Fig. 2 b are simple cylinder threedimensional model element attributes.
Fig. 3 is the object module schematic diagram read in based on OpenGL programmings, wherein, Fig. 3 a are KH-12 dummy satellites；Fig. 3 b
It is simple cylinder model.
Fig. 4 is OpenGL coordinate systems and anglec of rotation schematic diagram.
Fig. 5 is lambert's cylinder schematic diagram.
Fig. 6 is inventive algorithm and theoretical value contrast schematic diagram；Wherein, Fig. 6 a are that OCS result of calculations contrast in experiment 1
Figure；Fig. 6 b are OCS calculation error figures in experiment 1；Fig. 6 c are OCS result of calculation comparison diagrams in experiment 2；Fig. 6 d are OCS in experiment 2
Calculation error figure.
Fig. 7 is the flow chart of the present invention.
Embodiment
Quickly to be counted as shown in fig. 7, the embodiments of the invention provide a kind of extraterrestrial target OCS based on OpenGL dual picks
Calculation method, including：
Step 1: extraterrestrial target is modeled using 3 d modeling software；
Step 2: parse threedimensional model and name each bin；
Step 3: using OpenGL rendering models, visible bin pickup is carried out to model according to detector orientation, according to light
Source orientation carries out illumination bin pickup to model, obtains two bin set；
Step 4: occuring simultaneously to the bin collection conjunction picked up twice in step 3, the visible illumination bin of detector is obtained；
Step 5: calculating the OCS values of each bin in the common factor obtained, all bin OCS that add up are worth to extraterrestrial target
OCS values.
It is described that extraterrestrial target is modeled using 3 d modeling software in step 1, including：Using 3 d modeling software to sky
Between target be modeled, model is divided into several Triangular object models, and retain the information of each bin, file is preserved into .3ds
Form.
The 3 d modeling software is Creator or 3DMAX；And/or
The information for retaining each bin, including retain the material and vertex information of each bin.
In step 2, the parsing threedimensional model simultaneously names each bin, including：Model file in analyzing step one,
Named to each Triangular object model parsed and record its summit, material information；
In step 3, it is also necessary to open OpenGL depth buffers and depth test, object module is being drawn based on OpenGL
Mutual hiding relation between Shi Tixian bins.
In step 3, when carrying out visible bin pickup, the observation visual angle to object module, observation visual angle are set twice
Determined by the actual illumination of extraterrestrial target and observation angle；And/or
Described pickup is the method that OpenGL obtains designated area bin information, pickup scope be whole drawing window with
Ensure to cover model region；And/or
It is described according to light source azimuth to model carry out illumination bin pickup, based on the extraterrestrial target run in track only by
The illumination of the sun.
In step 4, the visible illumination bin of detector that obtains is as the effective bin for calculating whole model OCS, ginseng
Calculated with follow-up OCS.
In step 5, the OCS values of each bin in the common factor of acquisition are calculated, including according to each bin vertex information computational chart
Face normal vector and bin area, its OCS is calculated with reference to each bin material.
When calculating the single effectively OCS of bin, calculate area, normal vector used in OCS and be all from solving in step 2
The data of analysis；The bin Material Name parsed according to step 2, in conventional extraterrestrial target Facing material BRDF, (bidirectional reflectance is distributed
Function) the BRDF parameters of the material are obtained in database；The OCS values of the bin are calculated with reference to above-mentioned parameter；And/or
Preferably, the conventional extraterrestrial target Facing material BRDF databases, to store conventional extraterrestrial target surface material
The BRDF parameters of matter, the database can be measured by BRDF measuring apparatus and obtain initial data, and then can calculate Phong moulds
The parameter value of the BRDF models such as type, five parameter semiempirical statistical models.For lambert's body target, can be resolved according to its reflectivity
BRDF。
The OCS values for calculating extraterrestrial target, refer on the basis of each effectively bin OCS calculating, will be all effective
Bin OCS values are cumulative to obtain the OCS values of whole extraterrestrial target model.
The step of being proposed according to the above embodiment of the present invention, embodiment is decomposed as follows：
1) extraterrestrial target three-dimensional modeling
Extraterrestrial target is modeled using 3 d modeling software, model is divided into some Triangular object models and retains bin
Material information, file preserved into ' .3ds ' form.Fig. 1 is the result being modeled using Creator 2.6 to KH-12 satellites
(Fig. 1 a) and its element attribute (Fig. 1 b).Attribute includes component names, texture and bin quantity, and wherein title (' Name ') is mould
The component names that type is included, different parts, texture or material are general also different.The total bin quantity of the model is more than 5000
It is individual, belong to complex target.The object module of simple shape can certainly be established, cylinder as shown in Figure 2 only has a kind of material
Matter, bin quantity also only have 396.
2) parse ' .3ds ' model file and redraw threedimensional model using OpenGL
' .3ds ' model file has unified structure, is easy to programming to read.The form can stably preservation model grid
Information and texture mapping information, are also compatible with underlying bones and basic animation.3ds model files are formed by many pieces, and each block is first
Thereafter information category is first described, i.e., how the block forms, and the information category of block identifies that block further comprises with ID
Next piece of relative position information, therefore, even if not knowing about the implication of a block, it can also be easily skipped, because
The next piece of skew byte number relative to the block original position is indicated in current block.When reading 3ds files, the present invention is only
Vertex data, each object Material Name and bin index information, other information need to be read then to skip.
In 3ds file structures, the bin quantity that each part contains is different, and each bin then includes corresponding summit respectively
Index to determine three point coordinates.The bin of reading is stored in chained list in order, each bin comprising numbering, vertex index,
The information such as material.
According to the Triangular object model information stored in chained list, bin is drawn out one by one using OpenGL.Need exist for noting
Meaning, needed while bin is drawn to each bin name (utilize OpenGL orders glLoadName (m_iName),
Wherein m_iName is bin title), the entitled integer numeral since 0, the purpose of name is easy for subsequently being picked up.
(Fig. 3 a are KH-12 dummy satellites to the object module drawn according to the method described above, and Fig. 3 b are simple circles as shown in Figure 3
Type cylinder models), due to not needing texture information when bin picks up, the bin of drafting is also just without stickup texture picture.
3) illumination bin and the visible bin of detector are picked up using OpenGL pickups function
Before being picked up, first have to rotate model to appropriate visual angle.
The rotation at illumination visual angle, that is, need that (user perspective is along Z by the image projection that illumination is seen to user perspective
Axle forward direction hopes that, to origin, origin is the center of drawing window) under.In OpenGL rendering models, window is being drawn at coordinate system center
The center of mouth, X-axis is from origin to the right for just, Y-axis is then from origin upwards for just, Z axis and XOY plane are in right-handed system, such as Fig. 4
It is shown.
Order from the origin of coordinates to light source the unit vector of (sun) be, will under OpenGL coordinate systems
The anglec of rotation that illumination visual angle rotates to be user perspective is
On the basis of two above angle is resolved, twice call OpenGL rotation functions, complete around X-axis rotation and around
The rotation of Y-axis, rotation function are as follows
After sun visual angle is rotated to user perspective according to the method described above, function is picked up to visible bin using OpenGL
It is picked up.Pickup scope should be set before pickup, pickup scope of the invention is whole drawing window, and phase is arrived in pickup result storage
Answer in array, remember that its bin collection is combined into A1.
Equally, after detector observation visual angle is rotated to user perspective, the visible bin of detector is picked up and remembered
Its bin collection is combined into A2.
A=A1 ∩ A2 are taken, wherein " ∩ " represents to occur simultaneously, then the bin in set A is the visible illumination bin of detector, will
Follow-up OCS is participated in calculate.
4) bin OCS is calculated
During target OCS based on finite element theory is calculated, integration is changed into cumulative, if there is N number of face in certain computing in set A
Member, then target OCS calculation formula be changed into
Wherein, AlFor the area of l-th of bin, θliFor the bin normal direction and solar vector (target's center to the sun
Vector) between angle, θlrBetween the bin normal direction and detector vector (vector of target's center to detector)
Angle, frFor the BRDF values of the material, it can read from database or be resolved according to its reflectivity.In the mistake of analytic modell analytical model
The coordinate on three summits of the bin has been obtained in journey, has been designated as respectivelyWith(arranged counterclockwise), then its per unit system
Line vectorAnd AlIt can be expressed as
Wherein,Multiplication cross is represented, ' | | ' represent modulus.
So far, all variables in l-th of bin OCS calculating process have showed, and then can be obtained according to formula (2)
To the OCS values of whole target.
5) checking of inventive algorithm
The actual value of complex target OCS values is difficult to obtain, and also model can not just be verified using complex target.In view of
There are analytic solutions in the OCS of simple geometry body, here by taking lambert's cylinder as an example, the checking present invention puies forward the correctness of algorithm.
Here two groups of different test angles, contrast theoretical value and Numerical Simulation Results of the present invention are taken respectively.Cylinder is sat
Mark system is as shown in Figure 5：
Wherein, OS is light source vector, and OD is detector vector, and OS and Y-axis angle are η, projections of the OS in XOZ planes with
Z axis overlaps, and the angle of OD and Y-axis is γ, and its projection and Z axis angle in XOZ planes is β, if the hemisphere of lambert's cylinder
Reflectivity is ρ2π, then its BRDF is ρ2π/π.Show that lambert's cylinder OCS expression formulas are as follows：
Wherein R is bottom surface radius, and L is cylinder height.Here R=1, L=5, ρ are taken2π=0.5.
Experiment 1：η=γ=0, β is made to calculate OCS and its error result as shown in Fig. 6 a, 6b by 0 ° to 180 ° change.It is real
Test 2：β=0, η=45 ° are made, γ calculates OCS and its error result as shown in Fig. 6 c, 6d by 0 ° to 180 ° change.
Abscissa is that (abscissa is β angles to angle value in Fig. 6 a, Fig. 6 b, and abscissa is γ angles in Fig. 6 c, Fig. 6 d in Fig. 6
Degree, unit are degree), ordinate is OCS values (as shown in Fig. 6 a, Fig. 6 c, unit is square metre) respectively and its percentage error is (by mistake
Difference and absolute value × 100 of theoretical value ratio, as shown in Fig. 6 b, Fig. 6 d, dimensionless).
By the above, contrast experiment can see, and the present invention carries algorithm and theoretical calculation degree is higher, and error is respectively less than
0.08%, show that its precision is higher.Algorithm is run under internal memory 4G, dominant frequency 3.3GHz 32 Win7 operating systems, is completed complete
The OCS computings that portion is 180 times, required time are about 2 seconds, and average single operation time only has 0.01 second, it is seen that its calculating speed it
Hurry up, this also fully demonstrated the present invention quick and precisely the characteristics of.It is complete for complex target model KH-12 of the bin more than 5000
14 seconds are needed into the OCS computings of 180 times, average single operation time is less than 0.1 second, fully meets the reality to complex target OCS
When high-accuracy arithmetic demand.
Claims (10)
1. the extraterrestrial target OCS quick calculation methods based on OpenGL dual picks, including：
Step 1: extraterrestrial target is modeled using 3 d modeling software；
Step 2: parse threedimensional model and name each bin；
Step 3: using OpenGL rendering models, visible bin pickup is carried out to model according to detector orientation, according to light source side
Position carries out illumination bin pickup to model, obtains two bin set；
Step 4: occuring simultaneously to the bin collection conjunction picked up twice in step 3, the visible illumination bin of detector is obtained；
Step 5: calculating the OCS values of each bin in the common factor obtained, all bin OCS that add up are worth to the OCS of extraterrestrial target
Value.
2. the extraterrestrial target OCS quick calculation methods based on OpenGL dual picks, its feature exist as claimed in claim 1
In,
It is described that extraterrestrial target is modeled using 3 d modeling software in step 1, including：Using 3 d modeling software to space mesh
Mark is modeled, and model is divided into several Triangular object models, and retains the information of each bin, and file is preserved into .3ds lattice
Formula.
3. the extraterrestrial target OCS quick calculation methods based on OpenGL dual picks, its feature exist as claimed in claim 2
In,
The 3 d modeling software is Creator or 3DMAX；And/or
The information for retaining each bin, including retain the material and vertex information of each bin.
4. the extraterrestrial target OCS quick calculation methods based on OpenGL dual picks as described in one of claims 1 to 3, its
It is characterised by,
In step 2, the parsing threedimensional model simultaneously names each bin, including：Model file in analyzing step one, to every
One Triangular object model parsed is named and records its summit, material information；
5. the extraterrestrial target OCS quick calculation methods based on OpenGL dual picks, its feature exist as claimed in claim 1
In,
In step 3, it is also necessary to open OpenGL depth buffers and depth test, the body when drawing object module based on OpenGL
Mutual hiding relation between existing bin.
6. the extraterrestrial target OCS quick calculation methods based on OpenGL dual picks as described in claim 1 or 5, its feature
It is,
In step 3, when carrying out visible bin pickup, the observation visual angle to object module is set twice, observation visual angle is by sky
Between the actual illumination of target and observation angle determine；And/or
The described pickup of visible bin and the pickup of illumination bin is the method that OpenGL obtains designated area bin information, picks up model
Enclose be whole drawing window with ensure to cover model region；And/or
It is described that illumination bin pickup is carried out to model according to light source azimuth, based on the extraterrestrial target run in track only by the sun
Illumination.
7. the extraterrestrial target OCS quick calculation methods based on OpenGL dual picks, its feature exist as claimed in claim 1
In,
In step 4, the effective bin for obtaining the visible illumination bin of detector as the whole model OCS of calculating, after participation
Continuous OCS is calculated.
8. the extraterrestrial target OCS quick calculation methods based on OpenGL dual picks, its feature exist as claimed in claim 1
In,
In step 5, the OCS values of each bin in the common factor of acquisition are calculated, including according to each bin vertex information gauging surface method
Line vector and bin area, its OCS is calculated with reference to each bin material.
9. the extraterrestrial target OCS quick calculation methods based on OpenGL dual picks, its feature exist as claimed in claim 8
In,
When calculating the single effectively OCS of bin, calculate area, normal vector used in OCS and be all from what is parsed in step 2
Data；The bin Material Name parsed according to step 2, in conventional extraterrestrial target Facing material BRDF（Bidirectional reflectance is distributed letter
Number）The BRDF parameters of the material are obtained in database；The OCS values of the bin are calculated with reference to above-mentioned parameter；And/or
The conventional extraterrestrial target Facing material BRDF databases, to store the BRDF of conventional extraterrestrial target Facing material ginsengs
Number, the database can be measured by BRDF measuring apparatus and obtain initial data, and then can calculate Phong models, five parameters half
The parameter value of empirical model；For lambert's body target, BRDF can be resolved according to its reflectivity.
10. the extraterrestrial target OCS quick calculation methods based on OpenGL dual picks, its feature exist as claimed in claim 1
In,
The OCS values for calculating extraterrestrial target, refer on the basis of each effectively bin OCS calculating, will whole effective bins
OCS values are cumulative to obtain the OCS values of whole model.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103487789A (en) * | 2013-09-23 | 2014-01-01 | 北京航空航天大学 | Radar cross section quick acquisition method applied to multiple scattering of complex target |
| CN104573257A (en) * | 2015-01-22 | 2015-04-29 | 北京航空航天大学 | High-speed algorithm for judging electromagnetic shelter based on surface element space diversity |
| CN104573368A (en) * | 2015-01-13 | 2015-04-29 | 北京航空航天大学 | Surface element projection based triangular cross-sectional ray tube electromagnetic ray tracing algorithm |
-
2015
- 2015-11-16 CN CN201510784884.9A patent/CN105405144B/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103487789A (en) * | 2013-09-23 | 2014-01-01 | 北京航空航天大学 | Radar cross section quick acquisition method applied to multiple scattering of complex target |
| CN104573368A (en) * | 2015-01-13 | 2015-04-29 | 北京航空航天大学 | Surface element projection based triangular cross-sectional ray tube electromagnetic ray tracing algorithm |
| CN104573257A (en) * | 2015-01-22 | 2015-04-29 | 北京航空航天大学 | High-speed algorithm for judging electromagnetic shelter based on surface element space diversity |
Non-Patent Citations (5)
| Title |
|---|
| 基于面元分组的电磁遮挡算法及其优化;姬金祖 等;《北京航空航天大学学报》;20090430;第35卷(第4期);第453-456页 * |
| 基于面元法的航母雷达散射截面计算;张国华 等;《国防科技大学学报》;20011231;第23卷(第5期);第79-83页 * |
| 基于面元网格化的空间目标光学特性计算方法;鲍文卓 等;《哈尔滨工业大学学报》;20100531;第42卷(第5期);第710-715页 * |
| 激光主动探测空间目标的成像仿真;韩意 等;《激光与红外》;20091031;第39卷(第10期);第1051-1054页 * |
| 目标表面遮蔽函数参数的反演与BRDF统计建模的优化;黄朝军 等;《红外与激光工程》;20101031;第39卷(第5期);第883-886、891页 * |
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