Aircraft ultraviolet radiation characterization method, device, computer equipment and storage medium

Abstract

The present invention provides a method, device, computer equipment and storage medium for characterizing aircraft ultraviolet radiation, the method comprising: obtaining the current state of motion and operating attitude of the aircraft, and the direction of sunlight; judging whether the aircraft is exposed to ultraviolet radiation according to the state of motion of the aircraft and the direction of sunlight; when the aircraft is exposed to ultraviolet radiation, analyzing the ultraviolet radiation conditions of different exposed surfaces of the aircraft according to the direction of sunlight and the attitude of the aircraft. The present invention characterizes the different degrees of ultraviolet radiation received by different parts of the aircraft surface by obtaining the state of motion and attitude of the aircraft and the direction of sunlight, taking into account the structures and exposed surfaces of different aircraft, and more realistically realizing real-time quantitative characterization of ultraviolet radiation during the on-orbit operation of the aircraft.

Description

Technical Field

[0001] The present invention relates to the field of aerospace technology, and in particular to an aircraft ultraviolet radiation characterization method, device, computer equipment and storage medium. Background Art

[0002] In the low earth orbit environment, in addition to atomic oxygen, which poses a serious threat to aircraft operating in low earth orbit, ultraviolet and vacuum ultraviolet radiation will also have an impact on aircraft materials. Although vacuum ultraviolet radiation accounts for a small proportion of the total solar radiation energy, its role is very important. Photons have very high energy and can strongly ionize the upper atmosphere of the earth to form an ionosphere. When they act on the surface of the aircraft, a photoelectric effect will occur, causing the surface of the aircraft to have static electricity, which will affect the normal operation of the electronic system and magnetic devices in the aircraft. When photons act on materials, the molecules in the materials will produce photoionization and photodecomposition effects, especially destroying the chemical bonds of the polymer materials on the aircraft, causing the materials to lose mass, causing the surface to have gas evolution, and deteriorating the mechanical properties. In addition, volatile condensables will affect the normal operation of the optical and electronic devices on the aircraft, and even cause them to fail. When the molecules on the surface of the material absorb radiation or the energy of radiation, chemical bonds may break, and corresponding physical and chemical changes may occur, thus affecting the structure and properties of the material.

[0003] Since low earth orbit vehicles are exposed to ultraviolet radiation during flight, the performance of the vehicle surface materials will be degraded, which may endanger the operational safety of the vehicle or reduce the service life of the vehicle. Therefore, it is necessary to study the effects of ultraviolet radiation on the vehicle. Summary of the invention

[0004] The problem solved by the present invention is how to characterize the ultraviolet radiation effect on the surface of an aircraft.

[0005] In order to solve the above problems, the present invention provides an aircraft ultraviolet radiation characterization method, comprising:

[0006] Get the current state of motion and attitude of the aircraft, and the direction of sunlight;

[0007] Determining whether the aircraft is exposed to ultraviolet radiation according to the motion state of the aircraft and the direction of the sunlight;

[0008] When the aircraft is exposed to ultraviolet radiation, the ultraviolet radiation conditions of different sun-exposed surfaces of the aircraft are analyzed according to the direction of the sunlight and the posture of the aircraft.

[0009] In one embodiment, obtaining the motion state of the aircraft at the current moment includes:

[0010] Get the relative position relationship between the aircraft and the earth at the current moment;

[0011] The step of judging whether the aircraft is exposed to ultraviolet radiation according to the motion state of the aircraft and the direction of the sunlight comprises:

[0012] Whether the aircraft is exposed to ultraviolet radiation is determined based on the relative position relationship between the aircraft and the earth and the direction of the sunlight.

[0013] In one embodiment, obtaining the relative position relationship between the aircraft and the earth at the current moment includes:

[0014] Using Kepler's six orbital elements to define the initial orbital parameters of the spacecraft;

[0015] According to the initial orbital parameters of the aircraft and the two-body motion equation, the spatial position coordinates of the aircraft in the geocentric J2000 coordinate system at the current moment are obtained.

[0016] In one embodiment, obtaining the direction of sunlight at the current moment includes:

[0017] Get the relative position relationship between the sun and the earth;

[0018] The direction of the sunlight is obtained according to the relative position relationship between the sun and the earth.

[0019] In one embodiment, obtaining the relative position relationship between the sun and the earth includes:

[0020] Obtain the position coordinates of the sun in the second equatorial coordinate system, convert the position coordinates into an apparent position in a rectangular coordinate system relative to the earth through space, and obtain the position of the sun in the geocentric J2000 coordinate system according to the apparent position;

[0021] The step of obtaining the direction of the sunlight according to the relative position relationship between the sun and the earth comprises:

[0022] Assuming that the sunlight received by aircraft operating near the earth is all parallel light, the direction vector pointing from the center of the earth to the center of mass of the sun is obtained according to the position of the sun in the geocentric J2000 coordinate system, the direction vector is inverted and normalized to obtain the direction vector of the sun's ultraviolet light, which is the direction of the sun's rays.

[0023] In one embodiment, obtaining the current operating posture of the aircraft includes:

[0024] Define a satellite body coordinate system, the origin of the satellite body coordinate system is located at the center of mass of the aircraft, the X-axis, Y-axis, and Z-axis of the satellite body coordinate system are respectively the three principal inertia axes of the aircraft, and when the aircraft has no attitude deviation, the X-axis, Y-axis, and Z-axis of the satellite body coordinate system coincide with the X-axis, Y-axis, and Z-axis of the orbital coordinate system, the Z-axis of the orbital coordinate system points to the center of the earth, the X-axis of the orbital coordinate system coincides with the direction of movement of the aircraft, the Y-axis of the orbital coordinate system points to the negative normal direction of the orbital plane of the aircraft, and forms a right-handed rectangular coordinate system with the X-axis and Z-axis of the orbital coordinate system;

[0025] The attitude quaternion of the aircraft in the satellite body coordinate system at the current moment is obtained, and the attitude quaternion q is:

[0026]

[0027] Among them, q1, q2, q3 are vector components, q0 is a scalar component, and q1 2 +q2 2 +q3 2 +q0 2 =1, α is the angle required for the orbital coordinate system to rotate around the spatial rotation axis e to coincide with the satellite body coordinate system, wherein the direction vector of the spatial rotation axis e in the orbital coordinate system is e=(C x , C y , C z ), (C x , C y , C z ) represents direction cosines.

[0028] In one embodiment, judging whether the aircraft is exposed to ultraviolet radiation according to the motion state of the aircraft and the direction of the sunlight includes:

[0029] Obtaining a ground shadow obstruction area according to a relative position relationship between the sun and the earth and a relative position relationship between the aircraft and the earth;

[0030] Determine whether the aircraft enters the earth shadow shielding area when flying around the earth. When the aircraft does not enter the earth shadow shielding area, obtain the coordinates of the direction of the sunlight in the ntw coordinate system, and use the coordinates as the reference incident direction of ultraviolet rays irradiated by the aircraft.

[0031] Among them, the X-axis of the ntw coordinate system points to the forward direction of the aircraft, the Z-axis points to the outside of the center of the earth along the direction of the line connecting the center of the earth and the center of mass of the aircraft, and the Y-axis, X-axis and X-axis form a right-handed rectangular coordinate system.

[0032] The present invention also provides an aircraft ultraviolet radiation characterization device, comprising:

[0033] An acquisition unit is used to acquire the motion state and running attitude of the aircraft at the current moment, and the direction of the sun's rays;

[0034] an analysis unit, for determining whether the aircraft is exposed to ultraviolet radiation according to the motion state of the aircraft and the direction of the sunlight,

[0035] The analysis unit is also used to analyze the ultraviolet radiation conditions of different sun-exposed surfaces of the aircraft according to the direction of the sunlight and the posture of the aircraft when the aircraft is exposed to ultraviolet radiation.

[0036] The present invention also provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the above-mentioned method when executing the computer program.

[0037] The present invention also provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the steps of the aircraft ultraviolet radiation characterization method are implemented.

[0038] The advantages of the aircraft ultraviolet radiation characterization method of the present invention compared with the prior art are:

[0039] The present invention characterizes the different degrees of ultraviolet radiation received by different parts of the aircraft surface by acquiring the motion state and attitude state of the aircraft and the direction of sunlight. It takes into account the structures and sun-receiving surfaces of different aircraft and more realistically realizes real-time quantitative characterization of ultraviolet radiation during the aircraft's on-orbit operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a diagram of the application environment of the aircraft ultraviolet radiation characterization method in an embodiment of the present invention;

[0041] Figure 2 This is a flow chart of the method for characterizing aircraft ultraviolet radiation in an embodiment of the present invention;

[0042] Figure 3 Schematic diagram of the J2000 inertial coordinate system and the satellite body coordinate system in an embodiment of the present invention;

[0043] Figure 4 Schematic diagram of quaternion posture change in an embodiment of the present invention;

[0044] Figure 5 is a simulation calculation flow chart in an embodiment of the present invention;

[0045] Figure 6A diagram showing the spatial relative position relationship between the earth, the sun, and the aircraft in an embodiment of the present invention;

[0046] Figure 7 is the solar ultraviolet light direction output by simulation in the embodiment of the present invention;

[0047] Figure 8 Schematic diagram of an aircraft ultraviolet radiation characterization device in an embodiment of the present invention. DETAILED DESCRIPTION

[0048] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0049] Figure 1 FIG. 1 is an application environment diagram of the aircraft ultraviolet radiation characterization method in an embodiment of the present invention. Figure 1 , the aircraft ultraviolet radiation characterization method is applied to an aircraft ultraviolet radiation characterization system. The aircraft ultraviolet radiation characterization system includes a terminal 110 and a server 120. The terminal 110 and the server 120 are connected via a network. The terminal 110 can be a desktop terminal or a mobile terminal, and the mobile terminal can be at least one of a mobile phone, a tablet computer, a laptop computer, etc. The server 120 can be implemented by an independent server or a server cluster composed of multiple servers.

[0050] During the on-orbit operation of a spacecraft, different parts of the spacecraft's surface will be exposed to varying degrees of ultraviolet radiation due to factors such as its own motion state, attitude changes, its position relative to the sun, and the earth's obstruction, thus affecting the reliability of different positions of the spacecraft.

[0051] In order to characterize the different ultraviolet radiations received by different positions on the surface of an aircraft, an embodiment of the present invention provides a method for characterizing ultraviolet radiation of an aircraft, such as Figure 2 As shown, the method includes:

[0052] Step 210, obtaining the current motion state and running posture of the aircraft and the direction of sunlight;

[0053] Step 220, judging whether the aircraft is exposed to ultraviolet radiation according to the motion state of the aircraft and the direction of the sunlight;

[0054] Step 230: When the aircraft is exposed to ultraviolet radiation, the ultraviolet radiation conditions of different exposed surfaces of the aircraft are analyzed according to the direction of the sunlight and the posture of the aircraft.

[0055] In the embodiment of the present invention, when considering the different ultraviolet radiation levels on the surface of the spacecraft, since the surface of the spacecraft has a complex structure and shape, the ultraviolet radiation levels of various surfaces of the spacecraft will be affected by multiple factors at the same time. For example, considering that the motion state of the aircraft changes in real time during the on-orbit operation of the aircraft, it is necessary to solve the motion state of the aircraft in real time so as to obtain the latest real-time state of the aircraft. Therefore, in this embodiment, it is necessary to obtain the motion state and attitude state of the aircraft at the current moment. In order to be able to take into account the analytical and computational capabilities of different sun-exposed surfaces on the complex structure of the spacecraft, this embodiment also needs to obtain the direction of the sun's rays. Combining the above information, it is possible to solve whether the aircraft is exposed to ultraviolet light, and output the corresponding aircraft operation state at different times.

[0056] In some of the implementation modes, in step 210, obtaining the motion state of the aircraft at the current moment includes: obtaining the relative position relationship between the aircraft and the earth at the current moment, specifically including: using the six elements of the Kepler orbit to define the initial orbital parameters of the aircraft; according to the initial orbital parameters of the aircraft and the two-body motion equations, obtaining the spatial position coordinates of the aircraft in the geocentric J2000 coordinate system at the current moment.

[0057] Furthermore, judging whether the aircraft is exposed to ultraviolet radiation according to the motion state of the aircraft and the direction of the sunlight includes judging whether the aircraft is exposed to ultraviolet radiation according to the relative position relationship between the aircraft and the earth and the direction of the sunlight.

[0058] Here, a brief description of the time and coordinate system involved in the embodiments of the present invention is required.

[0059] In the solution process of the embodiment of the present invention, the simulation time is taken as the axis and the simulation step (seconds) determined by a user is taken as the time interval. The solution is performed moment by moment from the simulation start time until the simulation end time, so as to obtain the real-time and latest status of the aircraft during the orbital mission.

[0060] In this embodiment, Coordinated Universal Time (UTC) is used as the interface for users to connect to the start and end time of the simulation. Coordinated Universal Time, also known as the world's same time, is based on the length of the atomic second and is as close to Greenwich Mean Time (GMT) as possible. In order to ensure that the difference between Coordinated Universal Time and GMT does not exceed 0.9 seconds, the International Central Bureau for Earth Rotation Affairs in Paris will decide to add leap seconds to Coordinated Universal Time if necessary.

[0061] During the orbit calculation process of this embodiment, the mission time and current position of the satellite both use UTC time as input.

[0062] The internal solution process in this embodiment requires that the time change is mathematically calculable. For the convenience of calculation, the Julian day is used to represent the time. The Julian day is the number of days starting from 12h on January 1, 4573 BC. By converting the Gregorian calendar year, month and day into the Julian day, the description of the difference between two Gregorian calendar moments can be obtained under a unified specification, which is convenient for formulating the simulation step size. Similarly, the Julian day is also applicable to the calculation of the earth's rotation angle.

[0063] The formula for calculating the Julian day from the Gregorian calendar is:

[0064]

[0065] Among them, JD represents Julian day, INT() represents rounding, Year represents year in the Gregorian calendar, Month represents month, Day represents day, Hour represents hour, Minute represents minute, and Second represents second.

[0066] The embodiment of the present invention needs to solve each state quantity within each simulation moment to describe the position relationship of the earth in the universe and the flight position and flight attitude of the aircraft in the near-Earth space. The spatial reference coordinate system involved is defined as follows.

[0067] In the embodiment of the present invention, each main solution process is performed in the geocentric J2000 coordinate system. The J2000 coordinate system used is an inertial coordinate system, and the celestial reference coordinate system is defined by the celestial equator and the equinox at J2000 (12:00 on January 1, 2000). Figure 3 As shown, the origin of the J2000 coordinate system coincides with the center of mass of the earth, the X-axis points to the mean equinox at J2000, the Z-axis points to the North Pole, and the Y-axis, X-axis and Z-axis form a right-handed rectangular coordinate system, which is an inertial coordinate system.

[0068] The relative position relationship between the aircraft and the earth in the embodiment of the present invention takes into account that the mass of the earth is much greater than the mass of the aircraft, so a two-body motion model is used to solve the orbit calculation process, and the J2 perturbation term caused by the uneven distribution of the earth's mass is considered to solve the orbit. The initial orbit state of the aircraft is defined by the six elements of the Kepler orbit as a user interface for the user to initialize the satellite orbit mission parameters, specifically: 1) semi-major axis, a, describes the orbit size; 2) eccentricity, e, describes the orbit shape; 3) inclination, i, describes the inclination angle of the orbit plane relative to the equatorial plane; 4) ascending node right ascension, Ω, describes the position of the ascending node relative to the vernal equinox; 5) perigee argument, ω, describes the position of the perigee relative to the ascending node; 6) true anomaly, f, describes the position of the satellite relative to the perigee, and finally obtains the three-dimensional coordinates of the satellite's spatial position in the geocentric J2000 coordinate system.

[0069] In some of the implementation modes, in step 210, obtaining the direction of sunlight at the current moment includes: obtaining the relative position relationship between the sun and the earth, and obtaining the direction of the sunlight according to the relative position relationship between the sun and the earth.

[0070] Among them, obtaining the relative position relationship between the sun and the earth includes: obtaining the position coordinates of the sun in the second equatorial coordinate system, converting the position coordinates into an apparent position in the spatial rectangular coordinate system relative to the earth, and obtaining the position of the sun in the geocentric J2000 coordinate system based on the apparent position.

[0071] Furthermore, obtaining the direction of the sunlight according to the relative position relationship between the sun and the earth includes: assuming that the sunlight received by an aircraft operating near the earth is parallel light, obtaining a direction vector pointing from the center of the earth to the center of mass of the sun according to the position of the sun in the geocentric J2000 coordinate system, inverting the direction vector and normalizing it to obtain a direction vector of solar ultraviolet light, which is the direction of the sunlight.

[0072] In the embodiment of the present invention, considering that the distance between the earth and the sun is much greater than the radius of the sun, the sunlight near the earth uses a parallel light model, that is, it is assumed that the sunlight received by the spacecraft operating near the earth is all parallel light.

[0073] In order to solve the problem of solving the direction of the parallel light of the sun around the earth, it is necessary to solve the relative position relationship between the earth and the sun at any simulation time. The present embodiment adopts the star catalog data provided by the JPL laboratory to carry out mathematical modeling, and preferably adopts the DE404 star catalog. The base epoch time adopted is January 1, 2000. First, according to the correction formula of precession, nutation and aberration of light, the system time obtained in real time is converted to the Julian century number T calculated from the base epoch time, and then the mean position of the base epoch time of the star is corrected by itself with the Julian century number T as the parameter root, thus obtaining the position coordinates of the celestial body in the second equatorial coordinate system, and the coordinates are converted into the apparent position in the rectangular coordinate system of the space relative to the earth through space. Obtain the position of the sun in the geocentric J2000 coordinate system, and then obtain the direction vector of the parallel light of the sun.

[0074] In some implementation modes, in step 210, obtaining the current operating posture of the aircraft includes:

[0075] Define the satellite body coordinate system, and obtain the attitude quaternion of the aircraft in the satellite body coordinate system at the current moment. The attitude quaternion q is:

[0076]

[0077] Among them, q1, q2, q3 are vector components, q0 is a scalar component, and q1 2 +q2 2 +q3 2 +q0 2 =1, α is the angle required for the orbital coordinate system to rotate around the spatial rotation axis e to coincide with the satellite body coordinate system, wherein the direction vector of the spatial rotation axis e in the orbital coordinate system is e=(C x , C y , C z ), (C x , C y , C z ) represents direction cosines.

[0078] In the embodiment of the present invention, in order to describe the attitude change of the satellite body, the satellite body coordinate system is first defined. The origin of the satellite body coordinate system is located at the center of mass of the aircraft. The X-axis, Y-axis, and Z-axis of the satellite body coordinate system are the three principal inertia axes of the aircraft. In the absence of attitude deviation, the three coordinate axes of the satellite body coordinate system (Xs axis, Ys axis, and Zs axis) coincide with the satellite orbit coordinate system. At this time, the Zs axis of the satellite points to the center of the earth, the Xs axis direction coincides with the direction of satellite motion, and the Ys axis points to the negative normal direction of the satellite orbital plane, forming a right-handed rectangular coordinate system with the Xs axis and the Zs axis. Among them, Figure 3 Here α represents the orbital inclination, β represents the longitude of the ascending node, and δ represents the angular distance of the perihelion.

[0079] The posture description method involved in the embodiment of the present invention uses the quaternion posture description method because the Euler angle description method has a singularity problem, that is, there are two sets of Euler angle data describing the same posture state. Therefore, this embodiment uses the quaternion posture description method.

[0080] Quaternion consists of two parts: scalar and vector. The form is

[0081] q=q0+q1i+q2j+q3k=[q s ,q v ];

[0082] Among them, q s Represents the scalar part, the unit is 1; q v represents the vector part, i, j, k are imaginary units. i, j, k can be understood as unit vectors that are orthogonal to each other.

[0083] The geometric description of quaternion is that the direction vector of a certain rotation axis e in the orbital coordinate system is: e = (C x ,C y ,C z ), where C x ,C y ,Cz represents direction cosines, orbital coordinate system O O X O Y O Z O Rotate α around e to get the body coordinate system O b X b Y b Z b ,like Figure 4 As shown. Thus, the attitude quaternion q of the above satellite is obtained.

[0084] In some of the embodiments, judging whether the aircraft is exposed to ultraviolet radiation according to the motion state of the aircraft and the direction of the sunlight includes:

[0085] Obtaining a ground shadow obstruction area according to a relative position relationship between the sun and the earth and a relative position relationship between the aircraft and the earth;

[0086] Determine whether the aircraft enters the earth shadow shielding area when flying around the earth. When the aircraft does not enter the earth shadow shielding area, obtain the coordinates of the direction of the sunlight in the ntw coordinate system, and use the coordinates as the reference incident direction of ultraviolet rays to which the aircraft is irradiated.

[0087] In this embodiment, the calculation of the earth shadow shielding of the space set relationship of the aircraft is mainly performed by calculating whether the satellite flying around the earth enters the area that is not exposed to sunlight due to the earth shielding the ultraviolet radiation of the sun. The solution process is mainly based on the parallel ray model of the sun's ultraviolet light and the cylindrical shadow model of the earth shielding the sun's light to determine whether the aircraft is exposed to ultraviolet light data at each moment.

[0088] The calculation process of the algorithm of the present invention is as follows: when the satellite is operating in a near-Earth space mission orbit, the position of the satellite in space is calculated in real time based on the step size. In each step of the calculation, the three-dimensional coordinates of the satellite in space are calculated first, and then the satellite attitude is calculated, and then it is calculated whether the satellite is in the shadow shielding area. If it is irradiated by sunlight, the direction of the sun is output and used as the reference incident direction of ultraviolet rays. However, it is necessary to transform the direction vector of the solar ultraviolet light into the ntw coordinates of the aircraft ultraviolet solution, and consider the shielding relationship between complex structure spacecraft in combination with the aircraft attitude to characterize the ultraviolet irradiation of the spacecraft.

[0089] Among them, the X-axis of the ntw coordinate system points to the forward direction of the aircraft, the Z-axis points to the outside of the center of the earth along the direction of the line connecting the center of the earth and the center of mass of the aircraft, and the Y-axis, X-axis and X-axis form a right-handed rectangular coordinate system.

[0090] The present invention is further described below in conjunction with specific embodiments.

[0091] The task started at 12:0:00 on January 1, 2017, and the simulation step was 20 seconds.

[0092] In this embodiment, the spacecraft attitude and orbit parameters are initialized in the spacecraft mission. The six parameters of the spacecraft's initial orbit are: semi-major axis 6871 km, eccentricity 0, inclination 60 degrees, right ascension of ascending node 0 degrees, argument of perigee 0 degrees, and perigee angle 0 degrees.

[0093] The simulation calculation process of this embodiment is as follows Figure 5 As shown, the “initialization scenario” refers to receiving user requirements and initializing according to user requirements, including simulation start time, simulation end time, simulation step size, and orbit task initialization parameters.

[0094] After starting the simulation, first perform "orbit extrapolation calculation" to output the latest position coordinates of the aircraft at the current moment, such as Figure 6 As shown, the spatial relative position relationship between the earth, the sun and the spacecraft at 12:56:40 on January 1, 2017;

[0095] Then perform "Earth occlusion judgment" to output whether the aircraft is exposed to ultraviolet light;

[0096] Then solve the "ultraviolet light" and obtain the data of ultraviolet light in the ntw coordinate system, such as Figure 7 As shown, the simulation output is the direction of the solar ultraviolet light under the ntw coordinates of the aircraft at each simulation moment;

[0097] Then perform "structural occlusion characterization considering attitude" to output the latest attitude quaternion of the aircraft at the current moment;

[0098] Then determine whether the current simulation time is the "task end time". If not, the "time step" step amount is the simulation step length to obtain the next simulation time, and continue the cycle of the next simulation time. If so, end the entire simulation task.

[0099] Corresponding to the above-mentioned aircraft ultraviolet radiation characterization method, the embodiment of the present invention also provides an aircraft ultraviolet radiation characterization device, such as Figure 8 As shown, the device comprises:

[0100] An acquisition unit 810 is used to acquire the motion state and running posture of the aircraft at the current moment, and the direction of the sun's rays;

[0101] The analysis unit 820 is used to determine whether the aircraft is exposed to ultraviolet radiation according to the motion state of the aircraft and the direction of the sunlight.

[0102] The analysis unit 820 is also used to analyze the ultraviolet radiation conditions of different sun-exposed surfaces of the aircraft according to the direction of the sunlight and the posture of the aircraft when the aircraft is exposed to ultraviolet radiation.

[0103] Among them, the acquisition unit 810 shown obtains the motion state of the aircraft at the current moment, including: obtaining the relative position relationship between the aircraft and the earth at the current moment, specifically including: using the six elements of the Kepler orbit to define the initial orbital parameters of the aircraft, and according to the initial orbital parameters of the aircraft and the two-body motion equation, obtaining the spatial position coordinates of the aircraft in the geocentric J2000 coordinate system at the current moment.

[0104] The acquisition unit 810 acquires the current operating attitude of the aircraft, including: defining a satellite body coordinate system, and acquiring the attitude quaternion of the aircraft in the satellite body coordinate system at the current moment, wherein the attitude quaternion q is:

[0105]

[0106] Among them, q1, q2, q3 are vector components, q0 is a scalar component, and q1 2 +q2 2 +q3 2 +q0 2 =1, α is the angle required for the orbital coordinate system to rotate around the spatial rotation axis e to coincide with the satellite body coordinate system, wherein the direction vector of the spatial rotation axis e in the orbital coordinate system is e=(C x , C y , C z ), (C x , C y , C z ) represents direction cosines.

[0107] The acquiring unit 810 acquires the direction of the sunlight at the current moment by: acquiring the relative position relationship between the sun and the earth, and acquiring the direction of the sunlight according to the relative position relationship between the sun and the earth.

[0108] Among them, obtaining the relative position relationship between the sun and the earth includes: obtaining the position coordinates of the sun in the second equatorial coordinate system, converting the position coordinates into an apparent position in the rectangular coordinate system in space relative to the earth, and obtaining the position of the sun in the geocentric J2000 coordinate system based on the apparent position.

[0109] Obtaining the direction of the sunlight according to the relative position relationship between the sun and the earth includes: assuming that the sunlight received by the aircraft operating near the earth is parallel light, obtaining the direction vector from the center of the earth to the center of mass of the sun according to the position of the sun in the geocentric J2000 coordinate system, inverting the direction vector and normalizing it to obtain the direction vector of the sun's ultraviolet light, which is the direction of the sunlight.

[0110] The analyzing unit 820 determines whether the aircraft is exposed to ultraviolet radiation according to the motion state of the aircraft and the direction of the sunlight, including: determining whether the aircraft is exposed to ultraviolet radiation according to the relative position relationship between the aircraft and the earth and the direction of the sunlight. In a specific implementation, the data of whether the aircraft is exposed to ultraviolet radiation at each moment can be determined based on the parallel light model of the sun's ultraviolet light and the cylindrical shadow model of the earth blocking the sun's light.

[0111] When the aircraft is exposed to ultraviolet radiation, the analysis unit 820 transforms the direction vector of the sun's ultraviolet light into the ntw coordinates of the aircraft's ultraviolet solution, considers the occlusion relationship between complex structure spacecraft in combination with the aircraft's attitude, characterizes the spacecraft's ultraviolet radiation conditions, and analyzes the ultraviolet radiation conditions of different exposed surfaces of the aircraft.

[0112] In one embodiment, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the following steps when executing the computer program:

[0113] Get the current state of motion and attitude of the aircraft, and the direction of sunlight;

[0114] Determining whether the aircraft is exposed to ultraviolet radiation according to the motion state of the aircraft and the direction of the sunlight;

[0115] When the aircraft is exposed to ultraviolet radiation, the ultraviolet radiation conditions of different sun-exposed surfaces of the aircraft are analyzed according to the direction of the sunlight and the posture of the aircraft.

[0116] In one embodiment, a computer readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented:

[0117] Get the current state of motion and attitude of the aircraft, and the direction of sunlight;

[0118] Determining whether the aircraft is exposed to ultraviolet radiation according to the motion state of the aircraft and the direction of the sunlight;

[0119] When the aircraft is exposed to ultraviolet radiation, the ultraviolet radiation conditions of different sun-exposed surfaces of the aircraft are analyzed according to the direction of the sunlight and the posture of the aircraft.

[0120] In one embodiment, when the computer program is executed by a processor, the steps of the above-mentioned aircraft ultraviolet radiation characterization method are also implemented.

[0121] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided by the present invention can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0122] Although the disclosure is disclosed as above, the protection scope of the disclosure is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the disclosure, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A method for characterizing aircraft ultraviolet radiation, characterized in that: include: Get the current state of motion and attitude of the aircraft, and the direction of sunlight; Determining whether the aircraft is exposed to ultraviolet radiation according to the motion state of the aircraft and the direction of the sunlight; When the aircraft is exposed to ultraviolet radiation, analyzing the ultraviolet radiation conditions of different exposed surfaces of the aircraft according to the direction of the sunlight and the posture of the aircraft; The obtaining of the motion state of the aircraft at the current moment includes: obtaining the relative position relationship between the aircraft and the earth at the current moment; The obtaining of the direction of the sunlight at the current moment comprises: obtaining the relative position relationship between the sun and the earth; obtaining the direction of the sunlight according to the relative position relationship between the sun and the earth; The step of judging whether the aircraft is exposed to ultraviolet radiation according to the motion state of the aircraft and the direction of the sunlight comprises: Obtaining a ground shadow obstruction area according to a relative position relationship between the sun and the earth and a relative position relationship between the aircraft and the earth; Determine whether the aircraft enters the earth shadow shielding area when flying around the earth. When the aircraft does not enter the earth shadow shielding area, obtain the coordinates of the direction of the sunlight in the ntw coordinate system, and use the coordinates as the reference incident direction of ultraviolet rays irradiated by the aircraft. Among them, the X-axis of the ntw coordinate system points to the forward direction of the aircraft, the Z-axis points to the outside of the center of the earth along the direction of the line connecting the center of the earth and the center of mass of the aircraft, and the Y-axis, X-axis and X-axis form a right-handed rectangular coordinate system.

2. The method for characterizing aircraft ultraviolet radiation according to claim 1, characterized in that: The obtaining of the relative position relationship between the aircraft and the earth at the current moment includes: Using Kepler's six orbital elements to define the initial orbital parameters of the spacecraft; According to the initial orbital parameters of the aircraft and the two-body motion equation, the spatial position coordinates of the aircraft in the geocentric J2000 coordinate system at the current moment are obtained.

3. The method for characterizing aircraft ultraviolet radiation according to claim 1, characterized in that: The obtaining of the relative position relationship between the sun and the earth comprises: Obtain the position coordinates of the sun in the second equatorial coordinate system, convert the position coordinates into an apparent position in a rectangular coordinate system relative to the earth through space, and obtain the position of the sun in the geocentric J2000 coordinate system according to the apparent position; The step of obtaining the direction of the sunlight according to the relative position relationship between the sun and the earth comprises: Assuming that the sunlight received by aircraft operating near the earth is all parallel light, the direction vector pointing from the center of the earth to the center of mass of the sun is obtained according to the position of the sun in the geocentric J2000 coordinate system, the direction vector is inverted and normalized to obtain the direction vector of the sun's ultraviolet light, which is the direction of the sun's rays.

4. The method for characterizing aircraft ultraviolet radiation according to claim 1, characterized in that: The acquisition of the current operating attitude of the aircraft includes: Define a satellite body coordinate system, the origin of the satellite body coordinate system is located at the center of mass of the aircraft, the X-axis, Y-axis, and Z-axis of the satellite body coordinate system are respectively the three principal inertia axes of the aircraft, and when the aircraft has no attitude deviation, the X-axis, Y-axis, and Z-axis of the satellite body coordinate system coincide with the X-axis, Y-axis, and Z-axis of the orbital coordinate system, the Z-axis of the orbital coordinate system points to the center of the earth, the X-axis of the orbital coordinate system coincides with the direction of movement of the aircraft, the Y-axis of the orbital coordinate system points to the negative normal direction of the orbital plane of the aircraft, and forms a right-handed rectangular coordinate system with the X-axis and Z-axis of the orbital coordinate system; Get the attitude quaternion of the aircraft in the satellite body coordinate system at the current moment. for: ； in, represents the vector part, , , is the vector component, is a scalar component, and , is the angle required for the orbital coordinate system to rotate around the spatial rotation axis e to coincide with the satellite body coordinate system, wherein the direction vector of the spatial rotation axis e in the orbital coordinate system is , represents direction cosines.

5. An aircraft ultraviolet radiation characterization device, characterized in that: include: An acquisition unit is used to acquire the motion state and running attitude of the aircraft at the current moment, and the direction of the sun's rays; an analysis unit, for determining whether the aircraft is exposed to ultraviolet radiation according to the motion state of the aircraft and the direction of the sunlight, The analysis unit is also used to analyze the ultraviolet radiation conditions of different sun-exposed surfaces of the aircraft according to the direction of the sunlight and the posture of the aircraft when the aircraft is exposed to ultraviolet radiation; The acquisition unit includes a first acquisition unit, and the first acquisition unit is used to acquire the relative position relationship between the aircraft and the earth at the current moment; The acquisition unit further includes a second acquisition unit, the second acquisition unit being used to acquire the relative position relationship between the sun and the earth; and to acquire the direction of the sunlight according to the relative position relationship between the sun and the earth; The analysis unit is specifically used to obtain the earth shadow blocking area according to the relative position relationship between the sun and the earth and the relative position relationship between the aircraft and the earth; determine whether the aircraft enters the earth shadow blocking area when flying around the earth, and when the aircraft does not enter the earth shadow blocking area, obtain the coordinates of the direction of the sun's rays in the ntw coordinate system, and use the coordinates as the reference incident direction of ultraviolet rays irradiated by the aircraft, wherein the X-axis of the ntw coordinate system points to the forward direction of the aircraft, the Z-axis points to the outside of the earth's center along the direction of the line connecting the center of the earth and the center of mass of the aircraft, and the Y-axis, X-axis and X-axis form a right-handed rectangular coordinate system.

6. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the aircraft ultraviolet radiation characterization method according to any one of claims 1 to 4 are implemented.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the aircraft ultraviolet radiation characterization method according to any one of claims 1 to 4 are implemented.

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