CN-115931301-B - Spacecraft surface optical characteristic calculation method, device and storage medium

CN115931301BCN 115931301 BCN115931301 BCN 115931301BCN-115931301-B

Abstract

The invention provides a spacecraft surface optical characteristic calculation method, a device and a storage medium, wherein the method comprises the steps of 1, analyzing the surface micro-nano structure optical characteristic of a spacecraft to obtain the absorbance of the surface micro-nano structure, 2, obtaining new spacecraft surface element material information, 3, performing surface element treatment on the complex surface of the spacecraft to obtain spacecraft surface element normal direction and solar vector information under a J2000 coordinate system, 4, performing blanking judgment on the solar vector and the surface element normal direction to obtain effective surface element information, 5, performing optical scattering characteristic calculation on the effective surface element to obtain the surface element optical cross-sectional area, 6, accumulating all the surface element optical cross-sectional areas to obtain the overall optical cross-sectional area of the spacecraft, calculating the vision star and the like, and obtaining the optical characteristic of the spacecraft. The method has the advantage of high calculation precision, and can realize accurate calculation of the surface optical characteristics of the spacecraft.

Inventors

KANG GUOHUA
HU MIAOMIAO
QIU YUHUAN
WU JUNFENG
CHENG XUNLONG
WU JIAQI
YANG ZHENGHAO
TAO XINYONG
YUAN XINYU
FU YAO

Assignees

南京航空航天大学

Dates

Publication Date: 20260505
Application Date: 20220811

Claims (7)

1. The spacecraft surface optical property calculation method is characterized by comprising the following steps of: step 1, analyzing the optical characteristics of the micro-nano structure on the surface of the spacecraft by a finite time domain difference method to obtain absorbance A bs of the micro-nano structure on the surface; Step 2, endowing the spacecraft material information fr with the absorbance A bs of the surface micro-nano structure in a coefficient multiplication mode to obtain new spacecraft surface element material information (1-A bs ) fr; Step 3, performing surface element treatment on the complex surface of the spacecraft, and obtaining the surface element normal direction and solar vector information of the spacecraft under a J2000 coordinate system through coordinate system conversion; step 4, blanking judgment is carried out on the solar vector and the normal direction of the surface element, so that effective surface element information is obtained; Step 5, calculating the optical scattering characteristics of the effective surface element to obtain the surface element optical cross-sectional area; step 5 includes calculating the optical cross-sectional area of the bin using the formula : , Wherein f r is a bi-directional reflection distribution function of the bin, A bs is the absorption rate of light by the bin microstructure, dA k is the k-th bin area, N represents the total number of bins, theta i is the incident zenith angle, namely the included angle between a solar vector and a bin normal vector N, theta r is the observation zenith angle, namely the included angle between an observation vector and the bin normal vector N, and phi is the observation azimuth angle, namely the included angle between projections I 'and D' of the solar vector I and the observation vector D under the bin dA k ; The calculation formula of f r is as follows: , Wherein the method comprises the steps of Is the diffuse reflection coefficient of the material; specular reflection coefficient of the material; Is a mirror image index; The method comprises the steps of adjusting the reflection intensity of a mirror surface, adjusting the intermediate parameter a > 0, adjusting the intensity of a Fresnel phenomenon, and adjusting the increasing and decreasing speed of a mirror surface reflection component, wherein beta is an included angle between an observation direction and the mirror surface reflection direction, and beta = min { pi/2, beta }; And 6, accumulating the optical cross-sectional areas of all the surface elements to obtain the whole optical cross-sectional area of the spacecraft, calculating the stars and the like, and obtaining the optical characteristics of the spacecraft.
2. The method according to claim 1, wherein in step 1, the analyzing the optical characteristics of the micro-nano structure on the surface of the spacecraft comprises performing three-dimensional modeling of the micro-nano structure in optical characteristic analysis software, and calculating to obtain absorbance A bs of the micro-nano structure on the surface by using a finite time domain difference method.
3. The method according to claim 2, wherein in step 3, by reading an OBJ format file obtained by a bin segmentation software, bin material information after the absorbance of an additional microstructure and bin normal information under a body system are obtained, then according to six spacecraft orbits, position vector information of the spacecraft at each moment is obtained through recursion of an orbit dynamics equation, and a rotation matrix from the body system to a J2000 coordinate system is obtained, so that bin normal and solar vector information under the J2000 coordinate system are obtained.
4. A method according to claim 3, wherein step 4 comprises: Firstly judging self-shielding according to a vector method, and primarily screening effective surface elements, wherein the self-shielding judging conditions comprise: the normal included angle between the solar vector and the surface element is larger than 90 degrees, namely the surface element is not irradiated by sunlight; the normal included angle between the observation vector and the surface element is larger than 90 degrees, namely the surface element is not observed by the detector, If the bin meets any one of the two conditions, namely, judging the bin as an invalid bin and deleting the bin, then judging the mutual shielding of the rest bins according to a Z-buffer blanking algorithm to obtain a final effective bin, wherein the judging condition is that the bin depth value is the largest under the same sight.
5. The method of claim 4, wherein step 6 comprises taking the sun as a reference, knowing that the sun 'S star is equal to-26.74, and after S ocs is obtained, the star' S star is equal to m: , where R is the distance of the observation point from the spatial target.
6. A spacecraft surface optical property calculation apparatus implemented based on the method of any one of claims 1 to 5, comprising: The absorbance calculation module is used for analyzing the optical characteristics of the micro-nano structure on the surface of the spacecraft by a finite time domain difference method to obtain absorbance A bs of the micro-nano structure on the surface; The surface element material information calculation module is used for endowing the spacecraft material information fr with the absorbance A bs of the surface micro-nano structure in a coefficient multiplication mode to obtain new spacecraft surface element material information (1-A bs ) fr; The surface element processing module is used for performing surface element processing on the complex surface of the spacecraft, and acquiring the surface element normal direction and solar vector information of the spacecraft under a J2000 coordinate system through coordinate system conversion; the effective surface element information acquisition module is used for carrying out blanking judgment on the solar vector and the surface element normal direction to obtain effective surface element information; The surface element optical cross-sectional area calculation module is used for calculating the optical scattering characteristics of the effective surface element to obtain the surface element optical cross-sectional area; the optical characteristic calculation module of the spacecraft is used for accumulating the optical cross-sectional areas of all the surface elements to obtain the whole optical cross-sectional area of the spacecraft, calculating the stars and the like, and obtaining the optical characteristics of the spacecraft.
7. A storage medium storing a computer program or instructions which, when executed, implement the method of any one of claims 1 to 5.

Description

Spacecraft surface optical characteristic calculation method, device and storage medium Technical Field The present invention relates to the field of aerospace optics, and in particular, to a method and apparatus for calculating optical characteristics of a spacecraft surface, and a storage medium. Background With the continuous development of on-orbit detection technology, the current on-orbit detection of a spacecraft is developed into comprehensive detection of radar, optics, infrared, laser and the like. Especially for high-value spacecraft in high orbit, the main detection threat is optical detection. Therefore, the development of optical scattering characteristics and optical design research aiming at the high-orbit satellite has great strategic significance for detecting the enemy high-value satellite and hiding the enemy high-value satellite, breaking through the enemy space optical detection monitoring system, competing for space advantages and ensuring national safety. The spacecraft optical technology is a comprehensive technology adopted for reducing the visible light detectable information characteristic of the spacecraft, and aims to reduce the interception probability of an enemy detection system to the maximum extent or greatly shorten the detection distance of the enemy detection system so as to improve the survivability of the spacecraft. The spacecraft optical means mainly has 3 configurations, namely the probability of being detected is reduced by reducing the optical cross-sectional area (Optical Cross Section, OCS), the material is coated with optical absorption paint or is installed and loaded with the optical absorption material, and the maneuvering is carried out to avoid the reflection of sunlight to the observation direction through the posture adjustment. Wherein attitude maneuver is related to the capability of the platform itself, and the limitation is large. Currently mainly around the configuration and materials. However, the scattering characteristics of the spacecraft are less studied at present, and most of the scattering characteristics are focused on the research of macroscopic optical characteristics, so that the influence of the surface structure of the spacecraft on the optical characteristics of the spacecraft body is ignored, and the modeling of the optical characteristics of the surface of the spacecraft is not accurate enough, therefore, the prior art lacks an evaluation algorithm for the optical characteristics of the surface of the spacecraft, the optical characteristics of the spacecraft can be accurately calculated, and the effective evaluation of the performance is realized. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a spacecraft surface optical characteristic calculation method which can calculate and analyze the optical characteristic of a spacecraft, greatly improve the performance evaluation precision and realize the accurate modeling of the surface optical characteristic of the spacecraft. In order to achieve the above purpose, the invention adopts the following technical scheme: A spacecraft surface optical property calculation method comprises the following steps: step 1, analyzing the optical characteristics of the micro-nano structure on the surface of the spacecraft by a finite time domain difference method to obtain absorbance A bs of the micro-nano structure on the surface; Step 2, endowing the spacecraft material information fr with the absorbance A bs of the surface micro-nano structure in a coefficient multiplication mode to obtain new spacecraft surface element material information (1-A bs) fr; Step 3, performing surface element treatment on the complex surface of the spacecraft, such as surface element segmentation through 3Dmax, and obtaining the surface element normal direction and solar vector information of the spacecraft under a J2000 coordinate system through coordinate system conversion; step 4, blanking judgment is carried out on the solar vector and the normal direction of the surface element, so that effective surface element information is obtained; Step 5, calculating the optical scattering characteristics of the effective surface element to obtain the surface element optical cross-sectional area; And 6, accumulating the optical cross-sectional areas of all the surface elements to obtain the whole optical cross-sectional area of the spacecraft, calculating the stars and the like, and obtaining the optical characteristics of the spacecraft. In step1, analyzing the optical characteristics of the micro-nano structure on the surface of the spacecraft includes performing three-dimensional modeling on the micro-nano structure in optical characteristic analysis software (such as FDTD Solutions), and calculating by using a finite time domain difference method to obtain the absorbance A bs of the micro-nano structure on the surface. In step 3, by reading an OBJ format file obtained by bin segment