A representation method for spatial environment model

Abstract

The present invention provides a method for characterizing a space environment model, including: receiving a task start time, a task end time and a simulation step length; respectively initializing parameters of multiple orbit calculation models and multiple space environment models in an aircraft model; obtaining simulation time according to the task start time, the task end time and the simulation step length, and then respectively obtaining spatial position data of the aircraft at each simulation time and quantitative characterization data of the space environment of each aircraft under each space environment model through the simulation time; and comparing and analyzing the quantitative characterization data of the space environment of the aircraft under different space environment models. The method for characterizing a space environment model provided by the present invention can compare the advantages and disadvantages of different space environment models, and obtain information such as the accuracy, applicability and coverage of the space environment model, providing an important basis for the engineering application of the space environment model.

Description

Technical Field

[0001] The present invention relates to the field of aerospace engineering technology, and in particular to a method for analyzing an on-orbit environment of a spacecraft based on a space multi-radiation environment model. Background Art

[0002] As human beings' research on the space environment continues to deepen, the types and number of space environment models are also increasing. More and more space environment models need to be used and compared with similar existing environment models, so that the space environment models can be well applied to the quantitative characterization and analysis of the space environment during the on-orbit mission of the spacecraft. Therefore, a characterization method of the space environment model is urgently needed to obtain the characterization data of different space environment models during the on-orbit mission of the spacecraft, and to compare and verify the characterization data under different space environment models, so as to provide an important basis for the engineering application of the space environment model. Summary of the invention

[0003] The problem solved by the present invention is how to provide a characterization method for a space environment model, obtain characterization data of different space environment models in which a spacecraft is located during its on-orbit mission, and compare and verify the characterization data under different space environment models, thereby providing an important basis for the engineering application of the space environment model.

[0004] To solve at least one aspect of the above problems, the present invention provides a method for characterizing a spatial environment model, comprising the following steps:

[0005] Step S1, receiving task start time, task end time and simulation step length;

[0006] Step S2, respectively initializing the parameters of multiple orbit calculation models and multiple space environment models in the aircraft model to obtain the initialization parameters of the orbit calculation model and the initialization parameters of the space environment model;

[0007] Step S3, obtaining simulation time according to the task start time, the task end time and the simulation step length, and then obtaining spatial position data of the aircraft at each simulation time and spatial environment quantitative characterization data of the aircraft under each spatial environment model through the simulation time;

[0008] Step S4: performing comparative analysis on the space environment quantitative characterization data of the aircraft under different space environment models.

[0009] Preferably, in step S1, receiving the task start time, task end time and simulation step length includes:

[0010] The Coordinated Universal Time is used as a user description standard for the task start time and the task end time. During internal calculation, the task start time and the task end time are converted into the Julian day.

[0011] Preferably, in step S2, respectively initializing parameters of multiple orbit calculation models and multiple space environment models in the aircraft model includes:

[0012] The data of six orbit numbers corresponding to the mission start time of each orbit calculation model in the aircraft model are obtained; and the initialization parameters of each space environment model are obtained according to the use method of each space environment model.

[0013] Preferably, in step S3, obtaining the simulation time according to the task start time, the task end time and the simulation step length includes:

[0014] Starting from the task start time, the simulation step size is increased in sequence to obtain simulation moments until the task end time is reached, thereby obtaining a plurality of simulation moments between the task start time and the task end time.

[0015] Preferably, in step S3, obtaining the spatial position data of the aircraft at each simulation moment and the spatial environment quantitative characterization data of the aircraft under the spatial environment model at each simulation moment through the simulation moment includes:

[0016] At any simulation moment, the orbit calculation model of the aircraft model is traversed in turn to obtain the spatial position data of the aircraft at each simulation moment, and then in each aircraft model, each space environment model is traversed in turn, and according to the simulation moment and the corresponding space position data and the initialization parameters of the space environment model, the quantitative characterization data of the space where the aircraft is located is obtained.

[0017] Preferably, after step S3, the method further comprises:

[0018] The spatial quantitative characterization data is exported in the form of a data file, and the spatial quantitative characterization data is characterized by a three-dimensional space characterization method and a two-dimensional map characterization method.

[0019] Preferably, characterizing the spatial quantitative characterization data by a three-dimensional spatial characterization method includes:

[0020] Through the mission start time and the initialization parameters of the orbit calculation model, the earth, the sun, the moon, the aircraft and the starry sky background are located and displayed in the three-dimensional scene, the operation trajectory of the aircraft is drawn according to the spatial position information corresponding to each simulation moment, and the quantitative characterization data of the space environment are plotted on the operation trajectory according to the value-color scale to obtain a three-dimensional trajectory cloud map representing the space environment in which the aircraft is located.

[0021] Preferably, the characterizing the spatial quantitative characterization data by a two-dimensional map characterization method comprises:

[0022] The earth longitude and earth latitude of the sub-satellite point of the aircraft are located and displayed in a two-dimensional scene through the mission start time and the initialization parameters of the orbit calculation model. The operation trajectory of the aircraft is drawn according to the spatial position information corresponding to each simulation moment, and the quantitative characterization data of the space environment are plotted on the operation trajectory according to a numerical value-color scale to obtain a two-dimensional trajectory cloud map representing the space environment in which the aircraft is located.

[0023] Preferably, in step S4, the comparative analysis of the space environment quantitative characterization data of the aircraft under different space environment models includes:

[0024] The space environment characterization data of the aircraft under different space environment models are compared to obtain the accuracy, applicability and coverage of different space environment models.

[0025] The present invention determines multiple simulation moments for simulation calculation by receiving a mission start time, a mission end time and a simulation step size, and initializes the parameters of multiple orbit calculation models and multiple space environment models in the aircraft model respectively. Then, the spatial position data of the aircraft at each simulation moment and the spatial environment quantification data of the aircraft in different space environment models are calculated, and then the spatial environment quantification data of the aircraft in different space environment models are compared and verified, thereby comparing the advantages and disadvantages of different space environment models, and obtaining information such as accuracy, applicability and coverage of different space environment models through comparison, thereby providing an important basis for the engineering application of space environment models. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a flow chart of a method for characterizing a spatial environment model in an embodiment of the present invention;

[0027] Figure 2 Schematic diagram of a flow chart of a method for characterizing a spatial environment model in an embodiment of the present invention;

[0028] Figure 3A three-dimensional trajectory cloud map of the space environment model in an embodiment of the present invention;

[0029] Figure 4 It is a two-dimensional trajectory cloud map of the space environment model in an embodiment of the present invention. DETAILED DESCRIPTION

[0030] 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.

[0031] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention can be combined with each other. The meanings of the terms "comprising", "including", "containing", and "having" are non-restrictive, that is, other steps and other ingredients that do not affect the results can be added. The above terms cover the terms "consisting of..." and "consisting essentially of...". Unless otherwise specified, materials, equipment, and reagents are all commercially available. At the same time, it should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0032] The embodiment of the present invention provides a method for characterizing a spatial environment model, such as Figure 1 As shown, the following steps are included:

[0033] Step S1, receiving task start time, task end time and simulation step length;

[0034] Step S2, respectively initializing the parameters of multiple orbit calculation models and multiple space environment models in the aircraft model to obtain the initialization parameters of the orbit calculation model and the initialization parameters of the space environment model;

[0035] Step S3, obtaining simulation time according to the task start time, the task end time and the simulation step length, and then obtaining spatial position data of the aircraft at each simulation time and spatial environment quantitative characterization data of the aircraft under each spatial environment model through the simulation time;

[0036] Step S4: performing comparative analysis on the space environment quantitative characterization data of the aircraft under different space environment models.

[0037] In step S1, the coordinated universal time is used as the user description standard of the task start time and the task end time, and the task start time and the task end time are converted into the Julian day during internal calculation.

[0038] That is to say, the user enters the task start time and task end time in the form of coordinated universal time (year, month, day, minute, and second in the Gregorian calendar), which is convenient for engineering designers to use and set. During internal calculations, the task start time and task end time entered by the user are converted into Julian days. The Julian day is the number of days starting at 12h on January 1, 4573 BC. By converting UTC into Julian days, the description of the difference between two Gregorian calendar moments can be obtained under unified specifications, which is convenient for setting the simulation step size.

[0039] In step S2, the data of the six orbital numbers corresponding to the mission start time of each orbital calculation model of the aircraft model is obtained; according to the use method of each space environment model, the initialization control parameters of each space environment model are obtained. Among them, the six orbital numbers include perigee, apogee, orbital inclination, right ascension of ascending node, argument of perigee and true anomaly; according to the use method of each space environment model, depending on the specific space environment model, the necessary initialization control parameters of the space environment model are received to prepare for subsequent calculations.

[0040] In step S3, starting from the task start time, the simulation step length is sequentially increased to obtain simulation moments until the task end time is reached, and multiple simulation moments between the task start time and the task end time are obtained. That is, during the period from the task start time to the task end time, the simulation step length is sequentially increased on the basis of the task start time to obtain multiple simulation moments, and the obtained simulation moments are used in subsequent simulation calculation processes. Exemplarily, the task start time is set to 12:0:00 on January 1, 2017, the task end time is set to 12:0:00 on January 5, 2017, and the simulation step length is set to 20s, then 20s are sequentially increased on the basis of 12:0:00 on January 1, 2017 as the simulation moment until the task end time 12:0:00 on January 5, 2017 is reached.

[0041] After obtaining multiple simulation moments, at any simulation moment, each orbit calculation model in the aircraft model is traversed in turn to obtain the spatial position data of the aircraft at each simulation moment, and then in each orbit calculation model of the aircraft model, each space environment model is traversed in turn, and according to the simulation moment and the corresponding spatial position data and the initialization parameters of the space environment model, the quantitative characterization data of the space where the aircraft is located is obtained.

[0042] Exemplarily, the mission start time of 12:00:00 on January 1, 2017 is taken as the simulation time, and all orbit calculation models are traversed in sequence to obtain the space position data of the aircraft at 12:00:00 on January 1, 2017. Then, in each orbit calculation model of the aircraft model, each space environment model is traversed in sequence, and the simulation time and the space position data corresponding to the aircraft at the simulation time and the initialization parameters of the space environment model are input to obtain the space quantitative characterization data of the aircraft at the simulation time. By simulating and calculating all simulation moments from the mission start time to the mission end time, the space quantitative characterization data of the aircraft in different orbit calculation models and space environment models can be obtained.

[0043] like Figure 2 As shown, at the beginning of the simulation calculation, the parameters of the mission time, aircraft model and space environment model are initialized first. The mission time includes the mission start time, the mission end time and the simulation step size. The aircraft model parameters include the initialization parameters of the orbit calculation model in the aircraft model. The space environment model obtains the necessary initialization parameters of the space environment model according to the specific usage method; then, the flight state of the aircraft is quantitatively calculated according to the simulation time, and the spatial position data of the aircraft at the simulation time is obtained. Then, according to the simulation time and the corresponding spatial position data and the initialization parameters of the space environment model, a quantitative calculation based on the space environment model is performed to obtain the quantitative representation data of the space environment; then, the orbit calculation models of all space environment models and aircraft models are traversed to obtain all the spatial quantitative representation data of the simulation time, and then the next simulation time is calculated until the calculation data of all simulation times are obtained.

[0044] That is, the interface of the space environment model is divided into a time interface, a space interface and a model control interface for calculation and analysis of the space environment model. The time interface is the current simulation moment, the space interface is the spatial position data of the aircraft calculated according to the current simulation moment, and the model control interface is the initialization parameters of the space environment model. By updating the time interface and the space interface in real time, the spatial quantitative representation data of a space environment model at all simulation moments within the mission time (from the start time of the mission to the end time of the mission) can be obtained.

[0045] After step S3, the method further comprises:

[0046] The spatial quantitative characterization data is exported in the form of a data file, and the spatial quantitative characterization data is characterized by a three-dimensional space characterization method and a two-dimensional map characterization method.

[0047] That is to say, after the simulation calculation of steps S1-S3, the representation of the space environment model of the aircraft is represented by data file representation, three-dimensional space representation and two-dimensional map representation. The data file representation is the most original data information, which has the characteristics of real and reliable data and large data volume, but considering that the data are mainly numerical values, it lacks intuitiveness during use, and it is difficult to distinguish the characteristics in the data due to the large latitude of the data; the three-dimensional space representation can intuitively display the trajectory of the aircraft during the flight around the earth and the environment in front of the user, and can adjust the observation time and zoom in and out according to the needs of the user, so as to give the user an intuitive display, and represent the on-orbit mission status of the aircraft and the quality of the space environment, and support the user to switch different space environment model data and compare and verify the result differences between different space environment models; the two-dimensional map representation can intuitively display the changes in the longitude and latitude of the earth corresponding to the sub-satellite point during the on-orbit operation of the aircraft in front of the user, and can globally display the operation status of the space aircraft around the earth and the changes in the environment.

[0048] Specifically, the spatial quantitative characterization data is characterized by a three-dimensional spatial characterization method, including:

[0049] Through the mission start time and the initialization parameters of the orbit calculation model, the earth, the sun, the moon, the aircraft and the starry sky background are located and displayed in the three-dimensional scene, the operation trajectory of the aircraft is drawn according to the spatial position information corresponding to each simulation moment, and the quantitative characterization data of the space environment are plotted on the operation trajectory according to the value-color scale to obtain a three-dimensional trajectory cloud map representing the space environment in which the aircraft is located.

[0050] Characterizing the spatial quantitative characterization data by a two-dimensional map characterization method, including:

[0051] The earth longitude and earth latitude of the sub-satellite point of the aircraft are located and displayed in a two-dimensional scene through the mission start time and the initialization parameters of the orbit calculation model. The operation trajectory of the aircraft is drawn according to the spatial position information corresponding to each simulation moment, and the quantitative characterization data of the space environment are plotted on the operation trajectory according to a numerical value-color scale to obtain a two-dimensional trajectory cloud map representing the space environment in which the aircraft is located.

[0052] Among them, the three-dimensional space representation method is based on the OSG open source three-dimensional visualization computing and rendering library, and based on data-driven three-dimensional visualization representation technology, including the realization of the earth's near-space. The digital earth engine can support the display of multi-level map tile data, terrain data and place name label information. On the basis of the three-dimensional digital earth, it can support mission simulation and real-time display of space target posture.

[0053] Specifically, in the embodiment of the present invention, the ephemeris data is used to model the orbit of the celestial body in near-Earth space, and the running position and state of the earth, the moon, the sun and the galaxy are realistically simulated. The calculation process includes:

[0054] T1, according to the mathematical simulation system time, convert the time to the Julian day calculated from the base epoch time;

[0055] T2. Using the basic data of celestial bodies in the DE404 ephemeris as a reference, make corrections for precession, proper motion, nutation and aberration according to the celestial body calculation model to obtain the right ascension and declination of the celestial body in the second equatorial coordinate system;

[0056] T3. Through the coordinate conversion module, the coordinates obtained in step T2 are corrected into azimuth and elevation angles related to the longitude and latitude of the observation site, that is, converted into the apparent position in the rectangular coordinate system relative to the space where the earth is located.

[0057] The embodiment of the present invention performs mathematical modeling based on the ephemeris data provided by the JPL laboratory, adopts the DE404 ephemeris, and the reference epoch time is January 1, 2000.

[0058] Based on data-driven three-dimensional visualization of space scenes, we can realize three-dimensional visualization simulation of the operation of aircraft in the near-Earth space universe, and can realize three-dimensional visualization data color cloud map along the motion trajectory of the aircraft.

[0059] In addition, the spatial environment model is verified by the two-dimensional map representation method. The two-dimensional GIS map is divided into different levels of pixel calculation in the two-dimensional visualization through cloud map display, and the corresponding color of the scale corresponding to the pixel is obtained. The color is matched with the pixel to form a two-dimensional visualization spatial environment representation technology, so as to compare the data between different spatial environment models.

[0060] In step S4, the space environment characterization data of the aircraft under different space environment models are compared to obtain the accuracy, applicability and coverage of different space environment models.

[0061] Through steps S1-S3, the spatial quantitative characterization data of the space where the spacecraft is located during its on-orbit operation is calculated. The three-dimensional space characterization method and the two-dimensional map characterization method are combined to compare and verify the space environment model, so as to compare the advantages and disadvantages of different space environment models, and obtain information such as the accuracy, applicability and coverage of the space environment model, providing an important basis for the engineering application of the space environment model.

[0062] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples without specifying specific conditions are usually based on the conditions recommended by the manufacturer.

[0063] Example

[0064] 1.1. Receive the task start time, task end time and simulation step length. The task start time is 12:0:00 on January 1, 2017, the task end time is 12:0:00 on January 5, 2017, and the simulation step length is 20s.

[0065] 1.2. Obtain the data of the six orbital elements corresponding to the mission start time in the orbit calculation model of the aircraft model, which are: SAT_1: perigee 35759.3km, apogee 35759.3km, inclination 0 degrees, right ascension of ascending node 0 degrees, argument of perigee 0 degrees, perigee angle 0 degrees, SAT_2: apogee 26768km, perigee 1000km, inclination 63.4 degrees, right ascension of ascending node 0 degrees, argument of perigee 0 degrees, perigee angle 0 degrees, SAT_3: apogee 800km, perigee 800km, inclination 98 degrees, right ascension of ascending node 0 degrees, argument of perigee 0 degrees, perigee angle 0 degrees, SAT_4: apogee 400km, perigee 400km, inclination 51.5 degrees, right ascension of ascending node 0 degrees, argument of perigee 0 degrees, perigee angle 0 degrees, SAT_5: apogee 35870km, perigee 180km, inclination 6 degrees, right ascension of ascending node 0 degrees, argument of perigee 0 degrees, perigee angle 0 degrees, SAT_6: apogee 33000km, perigee 350km, inclination 18 degrees, right ascension of ascending node 0 degrees, argument of perigee 0 degrees, perigee angle 0 degrees; According to the method of using the space environment model, obtain the initialization parameters of the space environment model;

[0066] 1.3. Based on the task start time of 12:0:00 on January 1, 2017, the simulation time is increased by 20 seconds in sequence until the task end time of 12:0:00 on January 5, 2017 is reached;

[0067] 1.4. Take the mission start time of 12:00:00 on January 1, 2017 as the simulation time, traverse all orbit calculation models in turn, and obtain the space position data of the aircraft at 12:00:00 on January 1, 2017. Then, in each aircraft model, traverse each space environment model in turn, input the simulation time and the space position data corresponding to the aircraft at the simulation time, and the initialization parameters of the space environment model, and obtain the space quantitative representation data of the aircraft at the simulation time; by simulating and calculating all simulation times from the mission start time to the mission end time, the space quantitative representation data of the aircraft in different orbit calculation models and space environment models can be obtained;

[0068] 1.5. Based on the mission start time and the initialization parameters of the orbit calculation model, the earth, sun, moon, aircraft and starry sky background are located and displayed in the three-dimensional scene. The trajectory of the aircraft is drawn according to the spatial position information corresponding to each simulation moment, and the space environment quantitative characterization data is plotted on the trajectory according to the value-color scale to obtain a three-dimensional trajectory cloud map representing the space environment of the aircraft, such as Figure 3 As shown;

[0069] 1.6. The earth longitude and earth latitude of the sub-satellite point of the aircraft are located and displayed in a two-dimensional scene according to the mission start time and the initialization parameters of the orbit calculation model. The operation trajectory of the aircraft is drawn according to the spatial position information corresponding to each simulation moment, and the space environment quantitative characterization data is plotted on the operation trajectory according to the value-color scale to obtain a two-dimensional trajectory cloud map representing the space environment of the aircraft, such as Figure 4 shown.

[0070] like Figure 3 As shown in Figure 1, the three-dimensional trajectory cloud map obtained by the three-dimensional space representation method can verify the environmental distribution and changes of the space environment model in different regions of the earth; Figure 4 As shown, the two-dimensional trajectory cloud map obtained by the two-dimensional map characterization method can verify the changes in different environments of the aircraft during operation through the two-dimensional map trajectory of the sub-satellite point.

[0071] By switching between different spatial environment models of the same type of environment, different spatial quantitative characterization data can be obtained. By comparing and verifying the relative differences, applicable scopes and applicability of different spatial quantitative characterization data, the advantages and disadvantages of different spatial environment models can be compared. Through comparison, information such as the accuracy, applicability and coverage of different spatial environment models can be obtained, providing an important basis for the engineering application of spatial environment models.

[0072] 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 a spatial environment model, characterized in that: The following steps are involved: Step S1, receiving task start time, task end time and simulation step length; Step S2, obtaining data of six orbital numbers corresponding to the mission start time for each orbital calculation model in the aircraft model, respectively initializing parameters of multiple orbital calculation models and multiple space environment models in the aircraft model to obtain initialization parameters of the orbital calculation model, and obtaining initialization parameters of each space environment model according to the use method of each space environment model; Step S3, starting from the task start time, sequentially increase the simulation step length, obtain the simulation time, until the task end time is reached, obtain multiple simulation times from the task start time to the task end time, and then at any simulation time, sequentially traverse the orbit calculation model of the aircraft model to obtain the spatial position data of the aircraft at each simulation time, and then in each aircraft model, sequentially traverse each space environment model, and obtain the spatial quantitative characterization data of the aircraft according to the simulation time and the corresponding spatial position data and the initialization parameters of the space environment model; Exporting the spatial quantitative characterization data in the form of a data file, and characterizing the spatial quantitative characterization data by a three-dimensional spatial characterization method and a two-dimensional map characterization method; Step S4: performing comparative analysis on the spatial quantitative characterization data of the aircraft under different spatial environment models.

2. The method for characterizing a spatial environment model according to claim 1, characterized in that: In step S1, the receiving of the task start time, the task end time and the simulation step length includes: The Coordinated Universal Time is used as a user description standard for the task start time and the task end time. During internal calculation, the task start time and the task end time are converted into the Julian day.

3. The method for characterizing a spatial environment model according to claim 1, characterized in that: The characterizing the spatial quantitative characterization data by a three-dimensional spatial characterization method includes: Through the mission start time and the initialization parameters of the orbit calculation model, the earth, the sun, the moon, the aircraft and the starry sky background are located and displayed in the three-dimensional scene, the operation trajectory of the aircraft is drawn according to the spatial position information corresponding to each simulation moment, and the spatial quantitative characterization data is plotted on the operation trajectory according to the value-color scale to obtain a three-dimensional trajectory cloud map representing the space environment in which the aircraft is located.

4. The method for characterizing a spatial environment model according to claim 1, characterized in that: The characterizing the spatial quantitative characterization data by a two-dimensional map characterization method includes: The earth longitude and earth latitude of the sub-satellite point of the aircraft are located and displayed in a two-dimensional scene through the mission start time and the initialization parameters of the orbit calculation model. The operation trajectory of the aircraft is drawn according to the spatial position information corresponding to each simulation moment, and the spatial quantitative characterization data is plotted on the operation trajectory according to a numerical-color scale to obtain a two-dimensional trajectory cloud map representing the space environment in which the aircraft is located.

5. The method for characterizing a spatial environment model according to claim 1, characterized in that: In step S4, the comparative analysis of the spatial quantitative characterization data of the aircraft under different spatial environment models includes: The space environment characterization data of the aircraft under different space environment models are compared to obtain the accuracy, applicability and coverage of different space environment models.

Images