Mars atmospheric density inversion method, Mars atmospheric density inversion device and electronic equipment

Abstract

The invention discloses a Mars atmospheric density inversion method and device and electronic equipment, and relates to the field of aviation measurement and control or other related technical fields, and the method comprises the steps: monitoring the operation state of a Mars detector in a Mars detection orbit, and collecting the operation data of the Mars detector; drawing a running diagram of the Mars probe based on the running data; calculating the energy attenuation of the Mars probe on a near fire point on a working diagram and in each highly symmetric interval by using a highly symmetric principle and based on the operation data; inverting the average atmospheric density in each highly symmetric interval of the Mars atmosphere based on energy attenuation; and reducing the average atmospheric density in each height symmetric interval to a specific height position to obtain the atmospheric density of each height position of the Mars atmosphere. According to the invention, the technical problem that the measurement and control precision is low when the Mars atmospheric density is inverted by expanding the inversion time interval in the related technology is solved.

Description

Technical Field

[0001] The present invention relates to the field of aerospace measurement and control or other related technical fields. Specifically, it relates to a method and device for inverting the density of the Martian atmosphere, as well as an electronic device. Background Technique

[0002] In the field of aerospace measurement and control, especially in Mars exploration missions, understanding the characteristics of the Martian atmosphere is crucial for ensuring the safe operation of the detector. The atmospheric environment of Mars not only affects the orbit maintenance and adjustment of the detector, but also has a profound impact on the braking during the landing phase and the ballistic design of the sampling return mission. The accurate measurement of the Martian atmospheric density can provide key data support for the orbit design and control of the detector, ensuring that it can accurately execute the established tasks.

[0003] In the related art, the density of the Martian atmosphere is inverted by expanding the inversion time interval. This method can obtain relatively accurate energy attenuation to a certain extent. However, the consequence of this measurement and control method is that the height resolution of the inversion result will be reduced to dozens of kilometers. The height resolution here refers to the ability of the inversion method to distinguish the subtle changes in the atmospheric density in the vertical direction. When the integration interval increases, the inversion calculation actually takes the average atmospheric density of the atmospheric segment passed by the detector during this time interval as the output of the inversion. If the detector passes through an atmospheric layer with a height span of dozens of kilometers during this longer time period, then what is obtained by inversion will be a result containing the average value of the atmospheric density in the entire height interval, rather than the density value at a specific height. Physically, this means that the finally obtained density distribution is relatively rough and cannot accurately describe the atmospheric changes at each height, resulting in low measurement and control accuracy.

[0004] In view of the above problems, no effective solution has been proposed yet. Summary of the Invention

[0005] Embodiments of the present invention provide a method and device for inverting the density of the Martian atmosphere, as well as an electronic device, so as to at least solve the technical problem of low measurement and control accuracy in the related art when inverting the density of the Martian atmosphere by expanding the inversion time interval.

[0006] According to one aspect of an embodiment of the present invention, there is provided a method for inverting the density of the Martian atmosphere, including: monitoring the operating state of a Mars probe in a Mars exploration orbit and collecting the operating data of the Mars probe; drawing an operating graph of the Mars probe based on the operating data, wherein the height position of the periapsis and multiple height symmetric intervals of the Martian atmosphere are marked on the operating graph; using the height symmetry principle and calculating the energy attenuation due to atmospheric drag of the Mars probe at the periapsis and in each height symmetric interval on the operating graph based on the operating data; inverting the average atmospheric density in each height symmetric interval of the Martian atmosphere based on the energy attenuation; and reducing the average atmospheric density in each height symmetric interval to a specific height position to obtain the atmospheric density at each height position of the Martian atmosphere.

[0007] Optionally, after drawing the operating graph of the Mars probe based on the operating data, it further includes: determining the height position of the periapsis and the flight time when the Mars probe passes through the periapsis based on the operating trajectory in the operating graph; taking the height position of the periapsis as a reference position, dividing the operating graph into regions to obtain multiple height symmetric intervals and the corresponding end point flight times of each height symmetric interval, wherein the periapsis is the lowest point of the operating graph, the operating graph is symmetrically distributed on both sides with the periapsis as the center, and the height value of the maximum height of the height symmetric interval is less than or equal to a preset height threshold.

[0008] Optionally, the step of calculating the energy attenuation due to atmospheric drag of the Mars probe in each height symmetric interval on the operating graph based on the operating data includes: for each height symmetric interval, determining the minimum height and the maximum height of the height symmetric interval; calculating the energy attenuation when the Mars probe passes through the minimum height twice in the height symmetric interval to obtain a first energy attenuation; calculating the energy attenuation when the Mars probe passes through the maximum height twice in the height symmetric interval to obtain a second energy attenuation; using the height symmetry principle, calculating the difference between the first energy attenuation and the second energy attenuation, and obtaining the energy attenuation of the Mars probe in each height symmetric interval based on the difference, wherein the height symmetry principle means that when the Mars probe operates in the Mars exploration orbit, it will pass through each height symmetric interval twice, and the energy attenuation during the two passes through the same height symmetric interval is equal, and using the average value of the energy attenuation during the two passes through the same height symmetric interval as the energy attenuation of the Mars probe in this height symmetric interval.

[0009] Optionally, the step of calculating the energy decay of the Mars probe when passing through the minimum height twice in the height symmetry interval to obtain the first energy decay includes: determining two endpoint flight times corresponding to passing through the minimum height twice in the operation diagram, and obtaining the operation data of the Mars probe at each endpoint flight time; calculating the energy values of the Mars probe at each endpoint flight time based on the operation data of the Mars probe at each endpoint flight time and the energy calculation formula; calculating the difference between the energy values of the Mars probe at the two endpoint flight times to obtain the energy decay of the Mars probe when passing through the minimum height twice in the height symmetry interval, and obtaining the first energy decay.

[0010] Optionally, the energy calculation formula is expressed as: where m represents the mass of the probe, v represents the velocity of the probe, x and y represent the position of the probe, ω is the angular velocity of Mars' rotation, represents the kinetic energy of the probe, V S and V M represent the gravitational potential energy of the sun and Mars on the probe, represents the rotational potential energy generated by the rotation of Mars.

[0011] Optionally, the step of inverting the average atmospheric density in each height symmetry interval of the Mars atmosphere based on the energy decay includes: calculating the average atmospheric density in each height symmetry interval of the Mars atmosphere based on the energy decay of the Mars probe in each height symmetry interval and the atmospheric density inversion formula, where the atmospheric density inversion formula is expressed as: ρ represents the average atmospheric density in each height symmetry interval of the Mars atmosphere, ΔE represents the energy decay of the Mars probe in each height symmetry interval, represents the work done by the solar radiation pressure, C D is the drag coefficient, A is the windward area of the probe, m is the mass of the Mars probe, v represents the running velocity of the Mars probe, and Δt represents the time difference for the Mars probe to pass through each height symmetry interval.

[0012] Optionally, the step of reducing the average atmospheric density in each height symmetry interval to a specific height position includes: selecting multiple detection points in each height symmetry interval; calculating the atmospheric density of each detection point based on the relative atmospheric density formula; calculating the difference in atmospheric density between the atmospheric density of each detection point and the average atmospheric density of the height symmetry interval, and selecting the detection point with the smallest difference in atmospheric density as the target detection point of the height symmetry interval; reducing the average atmospheric density in the height symmetry interval to the height position corresponding to the target detection point of the height symmetry interval.

[0013] Optionally, the relative atmospheric density formula is expressed as: where ρ0 and ρ z are the atmospheric densities at heights z 0 and z respectively, m is the average molecular mass, g is the acceleration due to gravity, R is the ideal gas constant, and T is the temperature.

[0014] According to another aspect of the embodiments of the present invention, there is also provided an inversion device for the Martian atmospheric density, including: a collection unit for monitoring the operating state of a Mars probe in a Mars exploration orbit and collecting the operating data of the Mars probe; a plotting unit for plotting an operating diagram of the Mars probe based on the operating data, wherein the height position of the periapsis and multiple height symmetry intervals of the Martian atmosphere are marked in the operating diagram; a calculation unit for calculating the energy attenuation due to atmospheric drag of the Mars probe at the periapsis and in each height symmetry interval on the operating diagram by using the height symmetry principle and based on the operating data; an inversion unit for inversely calculating the average atmospheric density in each height symmetry interval of the Martian atmosphere based on the energy attenuation; and a reduction unit for reducing the average atmospheric density in each height symmetry interval to a specific height position to obtain the atmospheric density at each height position of the Martian atmosphere.

[0015] Optionally, the inversion device for the Martian atmospheric density further includes: a first determination module for determining the height position of the periapsis and the flight time when the Mars probe passes through the periapsis based on the flight trajectory in the operating diagram; a first division module for dividing the operating diagram with the height position of the periapsis as the reference position to obtain a plurality of the height symmetry intervals and the corresponding end-point flight times of each height symmetry interval, wherein the periapsis is the lowest point of the operating diagram, the operating diagram is symmetrically distributed on both sides with the periapsis as the center, and the height value of the maximum height of the height symmetry interval is less than or equal to a preset height threshold.

[0016] Optionally, the calculation unit includes: a second determination module configured to determine, for each of the height-symmetric intervals, the minimum height and the maximum height passed through by the height-symmetric interval twice; a first calculation module configured to calculate the energy attenuation of the Mars probe when passing through the minimum height twice in the height-symmetric interval to obtain a first energy attenuation; a second calculation module configured to calculate the energy attenuation of the Mars probe when passing through the maximum height twice in the height-symmetric interval to obtain a second energy attenuation; and a third calculation module configured to calculate, using the height-symmetry principle, the difference between the first energy attenuation and the second energy attenuation, and obtain the energy attenuation of the Mars probe in each height-symmetric interval based on the difference, where the height-symmetry principle means that when the Mars probe operates on the Mars exploration orbit, it will pass through each height-symmetric interval twice, and the energy attenuation when passing through the height-symmetric interval twice is equal, and the average of the energy attenuations when passing through the same height-symmetric interval twice is used as the energy attenuation of the Mars probe in the height-symmetric interval.

[0017] Optionally, the first calculation module includes: a first acquisition sub-module configured to determine, in the operation diagram, the two end-point flight times corresponding to passing through the minimum height twice, and acquire the operation data of the Mars probe at each end-point flight time; a first calculation sub-module configured to calculate the energy values of the Mars probe at each end-point flight time based on the operation data of the Mars probe at each end-point flight time and the energy calculation formula; and a second calculation sub-module configured to calculate the difference between the energy values of the Mars probe at the two end-point flight times to obtain the energy attenuation of the Mars probe when passing through the minimum height twice in the height-symmetric interval, and obtain the first energy attenuation.

[0018] Optionally, the energy calculation formula is expressed as: where m represents the mass of the probe, v represents the velocity of the probe, x and y represent the position of the probe, ω is the angular velocity of Mars' rotation, represents the kinetic energy of the probe, V S and V M represent the gravitational potential energy of the sun and Mars on the probe, represents the rotational potential energy generated by Mars' rotation.

[0019] Optionally, the inversion unit includes: a fourth calculation module configured to invert the average atmospheric density in each height-symmetric interval of the Mars atmosphere based on the energy attenuation of the Mars probe in each height-symmetric interval and the atmospheric density inversion formula, where the atmospheric density inversion formula is expressed as: ρ represents the average atmospheric density in each height-symmetric interval of the Mars atmosphere, ΔE represents the energy attenuation of the Mars probe in each height-symmetric interval, represents the work done by the solar radiation pressure, C DCd is the drag coefficient, A is the frontal area of the detector, m is the mass of the Mars detector, v represents the running speed of the Mars detector, and Δt represents the time difference of the Mars detector passing through each height symmetric interval.

[0020] Optionally, the reduction unit includes: a first selection module for selecting a plurality of detection points within each of the height symmetric intervals; a fifth calculation module for calculating the atmospheric density of each detection point based on the relative atmospheric density formula; a second selection module for calculating the atmospheric density difference between the atmospheric density of each detection point and the average atmospheric density of the height symmetric interval, and selecting the detection point with the smallest atmospheric density difference as the target detection point of the height symmetric interval; a first reduction module for reducing the average atmospheric density within the height symmetric interval to the height position corresponding to the target detection point of the height symmetric interval.

[0021] Optionally, the relative atmospheric density formula is expressed as: where ρ 0 and ρ z are the atmospheric densities at heights z 0 and z respectively, m is the average molecular mass, g is the acceleration due to gravity, R is the universal gas constant, and T is the temperature.

[0022] According to another aspect of the embodiments of the present invention, there is also provided an electronic device, including one or more processors and a memory, where the memory is used to store one or more programs, and when the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the inversion method of the Mars atmospheric density as described in any one of the above.

[0023] In this application, through the following steps: monitoring the operating state of the Mars detector in the Mars detection orbit, collecting the operating data of the Mars detector, and drawing an operating diagram of the Mars detector based on the operating data, where the height position of the periapsis and a plurality of height symmetric intervals of the Mars atmosphere are marked in the operating diagram, and then using the height symmetry principle and calculating the energy attenuation of the Mars detector due to atmospheric drag at the periapsis and within each height symmetric interval on the operating diagram based on the operating data, and inversely calculating the average atmospheric density within each height symmetric interval of the Mars atmosphere based on the energy attenuation, and finally reducing the average atmospheric density within each height symmetric interval to a specific height position to obtain the atmospheric density at each height position of the Mars atmosphere.

[0024] In this application, the operation data of the Mars probe in the Mars exploration orbit is collected in real time, and the Mars atmospheric density is inverted based on the real-time operation data. When inverting the Mars atmospheric density, the height symmetry method is adopted, which can invert the atmospheric density within a shorter time interval and a smaller height range, achieving the purpose of improving the height resolution of the atmospheric density inversion, obtaining the technical effect of enhancing the measurement and control accuracy of the Mars atmospheric density, and thus solving the technical problem in the related art that when inverting the Mars atmospheric density by expanding the inversion time interval, the measurement and control accuracy is relatively low. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings described herein are used to provide a further understanding of the present invention, form a part of this application, and the schematic embodiments and descriptions thereof of the present invention are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0026] Figure 1 is a flowchart of an optional method for inverting the Mars atmospheric density according to an embodiment of the present invention;

[0027] Figure 2 is an operation diagram of an optional Mars probe according to an embodiment of the present invention;

[0028] Figure 3 is a schematic diagram of the inversion principle of an optional Mars atmospheric density according to an embodiment of the present invention;

[0029] Figure 4 is a schematic diagram of an optional inversion process of the Mars atmospheric density according to an embodiment of the present invention;

[0030] Figure 5 is a schematic diagram of an optional inversion process based on height symmetry according to an embodiment of the present invention;

[0031] Figure 6 is a schematic diagram of an optional device for inverting the Mars atmospheric density according to an embodiment of the present invention;

[0032] Figure 7 is a hardware structure block diagram of an electronic device (or mobile device) for a method of inverting the Mars atmospheric density according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0034] It should be noted that the terms "first", "second", etc. in the specification, claims and above-mentioned drawings of the present invention are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0035] For the convenience of those skilled in the art to understand the present invention, the following explanations are made for some terms or nouns involved in the embodiments of the present invention:

[0036] Mars Atmosphere and Volatile Evolution mission, abbreviated as MAVEN, is a Mars exploration project used to study the upper atmosphere of Mars, especially the atmospheric escape process, and the interaction between the Martian atmosphere and the solar wind.

[0037] Atmospheric model MarsGram, a numerical model used to simulate and predict the state of the Martian atmosphere.

[0038] It should be noted that the method and device for inverting the Martian atmospheric density in this application can be used in the field of aerospace measurement and control technology. In the case of inverting the Martian atmospheric density based on the highly symmetric method, it can also be used in any field other than the field of aviation measurement and control. In the case of inverting the Martian atmospheric density based on the highly symmetric method, the application field of the method and device for inverting the Martian atmospheric density in this application is not limited.

[0039] It should be noted that the relevant information (including but not limited to user equipment information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in this application are information and data authorized by the user or fully authorized by all parties. And the processing of the relevant data, such as collection, storage, use, processing, transmission, provision, disclosure and application, all comply with the relevant laws, regulations and standards of the relevant regions, take necessary confidentiality measures, do not violate public order and good customs, and provide corresponding operation entrances for users to choose to authorize or refuse. For example, an interface is set between this system and relevant users or institutions. Before obtaining relevant information, a request for acquisition needs to be sent to the aforementioned users or institutions through the interface, and after receiving the consent information feedback from the aforementioned users or institutions, the relevant information is obtained.

[0040] It should be noted that when collecting and analyzing customer information in this application, corresponding operation entrances are provided for users to choose to agree or reject the results of automated decision-making; if the user chooses to reject, the expert decision-making process will be entered.

[0041] The following embodiments of the present invention can be applied to various systems / applications / devices for inverting the density of the Martian atmosphere. By drawing an operation diagram and adopting the highly symmetric method, the present invention can invert the density of the Martian atmosphere within a shorter time interval and a smaller altitude range, significantly improving the altitude resolution of the atmospheric density inversion, providing a more detailed altitude profile of the atmospheric density, and further improving the measurement and control accuracy and the accuracy of the measurement and control results.

[0042] By accurately calculating the energy attenuation of the detector on the large elliptical orbit due to atmospheric drag, this solution can more accurately reflect the impact of the atmospheric density on the aircraft, thereby improving the accuracy of the inverted density value.

[0043] When calculating the average atmospheric density on the Martian surface, the present invention not only considers the orbital accuracy of the interval endpoints within the highly symmetric interval of the Martian atmosphere, but also fully utilizes the orbital data at all times within the highly symmetric interval, enhancing the stability and reliability of the inversion results. At the same time, by reducing the average atmospheric density to a fixed altitude, the problem of unclear physical meaning of the average density in the traditional inversion method is overcome, providing density data with clear physical meaning for the orbital design and control of spacecraft.

[0044] The present invention will be described in detail below in conjunction with each embodiment.

[0045] Embodiment 1

[0046] According to an embodiment of the present invention, an embodiment of a method for inverting the density of the Martian atmosphere is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than here.

[0047] Figure 1 is a flowchart of an optional method for inverting the density of the Martian atmosphere according to an embodiment of the present invention, as Figure 1 shown, the method includes the following steps:

[0048] Step S101, monitor the operating state of the Mars detector in the Mars exploration orbit and collect the operating data of the Mars detector.

[0049] It should be noted that a Mars probe is a spacecraft specifically designed to explore Mars. It carries various scientific instruments and equipment and is capable of performing multiple tasks such as orbital flight, landing, and roving to study the geological structure, atmospheric environment, hydrological history, and potential signs of life on Mars.

[0050] Furthermore, a Mars exploration orbit refers to the orbital path along which a Mars probe orbits Mars. Depending on the different exploration tasks, the probe may adopt various orbital modes: a large elliptical orbit, where the orbit of the probe is elliptical, with a significant altitude difference between the periapsis (the point in the orbit closest to the Martian surface) and the apoapsis (the point in the orbit farthest from the Martian surface). This orbit allows the probe to conduct high-resolution observations at the periapsis and low-resolution but wide-coverage observations at the apoapsis, while using the gravity of Mars for orbital maneuvers to save fuel. A polar orbit, with an orbital inclination of 90 degrees, where the probe passes over the north and south poles of Mars, enabling uniform global coverage of Mars. A low orbit, which is relatively close to the Martian surface, allowing for high-resolution observations but requiring more fuel to counter atmospheric drag and maintain the orbit. A high orbit, which is farther from the Martian surface, suitable for global observations and communication relay, with less fuel consumption. When the Mars probe operates in the Mars exploration orbit, it needs to switch between different orbits according to different exploration tasks to adapt to different exploration stages and task requirements. For example, the probe may first conduct preliminary global observations in a high orbit and then reduce to a low orbit or a large elliptical orbit through orbital maneuvers for more detailed Mars exploration work.

[0051] Inverting the Martian atmospheric density based on the probe orbit data to obtain accurate Martian atmospheric density values can provide important data support for the orbital design of Mars probes, the landing braking, and the ballistic design of sample return, which is of great significance for Mars exploration. In step S101 above, when inverting the Martian atmospheric density, it is first necessary to continuously monitor the operating state of the Mars probe and collect in real-time the operating data of the Mars probe in the Mars exploration orbit, including key information such as its position, velocity, and orbital parameters. To ensure that all inversion calculations are performed based on accurate probe orbit state data, thereby improving the accuracy of atmospheric density inversion.

[0052] Step S102, draw an operation diagram of the Mars probe based on the operation data.

[0053] In the above step S102, an operation diagram of the Mars probe is drawn based on the real-time operation data of the Mars probe. By drawing the operation diagram, the position changes of the probe on the Mars exploration orbit can be clearly shown, including its latitude, longitude, and orbital altitude, so as to more intuitively present the operation state of the probe in the atmospheric environment at different altitudes, providing a visual reference and data basis for subsequent atmospheric density inversion. The height position of the periapsis and multiple height symmetry intervals of the Mars atmosphere are marked in the operation diagram. Generally speaking, the Mars atmosphere is very thin above 300 km. The periapsis and multiple height symmetry intervals within the height threshold range are important areas for atmospheric density inversion.

[0054] Figure 2 is an optional operation diagram of a Mars probe according to an embodiment of the present invention. As Figure 2 shown, the operation diagram takes time as the abscissa and operation altitude as the ordinate. The operation altitude refers to the height of the Mars probe from the Mars surface. In the related art, through the energy decay within a relatively large time range, such as the energy decay within the time range of [t 1 , t 2 , the atmospheric density within the height range of [h 1 , h 2 is inverted. Since the Mars atmosphere is very thin above 300 km, only when the probe passes near the periapsis does the energy change, and the time for the probe to pass through the periapsis is very short. Taking MAVEN as an example, the time for each orbit to operate below 300 km is only 700 - 900 s, and the shorter the force application time, the smaller the energy consumption. Therefore, when the traditional method inverses the atmospheric density near the periapsis, only by increasing the integration interval [t 1 , t 2 can a more accurate energy decay be obtained, resulting in a height resolution of the inversion result reaching dozens of kilometers, making the inversion result include the average atmospheric density within a relatively large height symmetry interval, that is, the finally obtained is a relatively rough density distribution, which cannot accurately describe the atmospheric changes at each height, resulting in a lower measurement and control accuracy.

[0055] Optionally, after drawing the operation diagram of the Mars probe based on the operation data, it further includes: determining the height position of the periapsis and the flight moment when the Mars probe passes through the periapsis based on the operation trajectory in the operation diagram; taking the height position of the periapsis as the reference position, dividing the operation diagram into regions, obtaining multiple height symmetry intervals and the corresponding endpoint flight moments of each height symmetry interval. Among them, the periapsis is the lowest point of the operation diagram, and the operation diagram is symmetrically distributed on both sides with the periapsis as the center. The height value of the maximum height of the height symmetry interval is less than or equal to a preset height threshold.

[0056] In some embodiments, after drawing the operation graph of the Mars probe based on the operation data, the operation trajectory of the Mars probe is divided into intervals through the operation graph to support more detailed and accurate atmospheric density inversion analysis. Specifically, the height position of the periapsis and the flight time when the Mars probe passes through the periapsis are determined through the lowest point of the operation graph, and with the periapsis as the reference position, multiple height-symmetric intervals are divided. Since the operation trajectory of the Mars probe is symmetrically distributed with the periapsis as the center point, each height-symmetric interval corresponds to four endpoint flight times. In addition, when the operation height reaches a certain threshold, the Martian atmosphere is thin, which has no practical significance for studying the Martian atmospheric density. Therefore, the selected height-symmetric intervals are all within the preset height threshold range.

[0057] It should be noted that the purpose of the region division is to decompose the operation graph into several symmetric sub-regions to facilitate the accurate inversion of the atmospheric density at each height.

[0058] Step S103: Utilize the height symmetry principle and calculate the energy attenuation due to atmospheric drag of the Mars probe on the operation graph at the periapsis and within each height-symmetric interval based on the operation data.

[0059] In the above step S103, after successfully drawing the operation graph of the Mars probe based on the operation data, the height symmetry principle is further adopted to analyze the energy attenuation of the probe affected by atmospheric drag near the periapsis and within each height-symmetric interval where it operates. Energy attenuation is the basis for inverting the atmospheric density. Figure 3 It is a schematic diagram of an optional inversion principle of the Martian atmospheric density according to an embodiment of the present invention. Based on the defect in the related art that the height resolution accuracy is relatively small due to increasing the integration interval for inverting the atmospheric density, the present application proposes to calculate the energy attenuation of the Mars probe within each height range through the height symmetry method. As Figure 3 shown, when the Mars probe operates on the Mars exploration orbit, it will pass through the same height twice. When the probe passes near the periapsis, the orbital height changes rapidly, while the changes in latitude and longitude are relatively small. There are two time intervals [t 2 , t 1 and [t' 1 , t' 2 , and the corresponding height change ranges of the probe are both [h 1 , h 2 . Thus, the Mars probe has two time intervals [t 2 , t 1 and [t' 1 , t' 2The average atmospheric density inside is almost equal, and the energy decay caused by atmospheric drag is also almost the same. Therefore, the average atmospheric density in this altitude range can be inverted by using the energy decays of the detector at the same altitude range in two time intervals, which can improve the altitude resolution of the inversion result.

[0060] Optionally, the steps of calculating the energy decay of the Mars detector due to atmospheric drag in each altitude symmetric interval on the operation graph based on the operation data include: for each altitude symmetric interval, determining the minimum altitude and the maximum altitude of the altitude symmetric interval; calculating the energy decay of the Mars detector when passing through the minimum altitude twice in the altitude symmetric interval to obtain the first energy decay; calculating the energy decay of the Mars detector when passing through the maximum altitude twice in the altitude symmetric interval to obtain the second energy decay; using the altitude symmetry principle, calculating the difference between the first energy decay and the second energy decay, and obtaining the energy decay of the Mars detector in each altitude symmetric interval based on the difference, where the altitude symmetry principle means that when the Mars detector operates on the Mars exploration orbit, it will pass through each altitude symmetric interval twice, and the energy decays when passing through this altitude symmetric interval twice are equal, and using the average value of the energy decays when passing through the same altitude symmetric interval twice as the energy decay of the Mars detector in this altitude symmetric interval.

[0061] Specifically, when calculating the energy decay in each altitude symmetric interval, first determine the maximum altitude and the minimum altitude of each altitude symmetric interval, and calculate the energy decays of the Mars detector when passing through the minimum altitude and the maximum altitude twice respectively to obtain the first energy decay and the second energy decay. According to the altitude symmetry principle, the Mars detector will pass through this altitude symmetric interval in two time intervals. Therefore, use the average value of the first energy decay and the second energy decay as the energy decay of the Mars detector when passing through this altitude symmetric interval.

[0062] Through the above steps, using the altitude symmetry method, the Mars atmospheric density can be inverted in a shorter time interval and a smaller altitude range, significantly improving the altitude resolution of the atmospheric density inversion, being able to provide a more detailed altitude profile of the atmospheric density, thereby improving the measurement and control accuracy and enhancing the accuracy of the measurement and control results.

[0063] Optionally, the steps of calculating the energy decay of the Mars detector when passing through the minimum altitude twice in the altitude symmetric interval to obtain the first energy decay include: determining the two end flight times corresponding to passing through the minimum altitude twice in the operation graph, and obtaining the operation data of the Mars detector at each end flight time; calculating the energy values of the Mars detector at each end flight time based on the operation data of the Mars detector at each end flight time and the energy calculation formula; calculating the difference between the energy values of the Mars detector at the two end flight times to obtain the energy decay of the Mars detector when passing through the minimum altitude twice in the altitude symmetric interval, and obtaining the first energy decay.

[0064] In some embodiments, when calculating the energy attenuation at the minimum altitude, it specifically includes: in the operation graph, find the flight times of the two end points corresponding to the minimum altitude. These two times respectively correspond to the moments when the Mars probe enters and leaves the minimum altitude. Thereby, the time range for calculating the energy attenuation is locked to ensure that the energy change is caused by the action of the Mars atmospheric drag on the probe. Then, according to the flight times of the end points, extract the operation data of the Mars probe at each flight time of the end points from the operation data, including but not limited to position, velocity, attitude, and mass, etc. These operation data are the basis for calculating the energy attenuation, and accurate data can ensure the reliability of the calculation results. Then, according to the energy calculation formula, calculate the energy values at each flight time of the end points, and calculate the difference between the energy values at the two flight times of the end points to obtain the energy attenuation caused by the atmospheric drag during the time when the Mars probe passes through the minimum altitude within the symmetric interval of a certain altitude twice. Similarly, following the above calculation steps of the energy attenuation, it is also possible to calculate the energy attenuation caused by the atmospheric drag during the time when the Mars probe passes through the maximum altitude within the symmetric interval of a certain altitude twice.

[0065] Optionally, the energy calculation formula is expressed as: where m represents the mass of the Mars probe, v represents the velocity of the Mars probe, x and y represent the position of the Mars probe, ω is the angular velocity of the Mars rotation, represents the kinetic energy of the Mars probe, V S and V M represent the gravitational potential energy of the sun and Mars on the Mars probe, represents the rotational potential energy generated by the Mars rotation.

[0066] In some embodiments, the energy attenuation of the Mars probe within the symmetric altitude interval is the basis for inverting the atmospheric density, and the energy attenuation is calculated based on the energy values of the Mars probe at each specific moment. Substitute the operation data of the Mars probe at each flight time of the end points into the energy calculation formula to calculate the energy values of the Mars probe at each flight time of the end points. The specific energy calculation formula can be expressed as: That is, the energy value is composed of the kinetic energy of the Mars probe, the gravitational potential energy of the sun and Mars on the Mars probe, and the rotational potential energy generated by the Mars rotation.

[0067] Step S104, invert the average atmospheric density within each symmetric altitude interval of the Mars atmosphere based on the energy attenuation.

[0068] It should be noted that after calculating the energy attenuation of the Mars probe passing through each symmetric altitude interval, the average atmospheric density within each symmetric altitude interval of the Mars atmosphere can be inverted according to the energy attenuation value.

[0069] Optionally, the step of inverting the average atmospheric density in each symmetric interval of different altitudes in the Martian atmosphere based on the energy decay includes: calculating the average atmospheric density in each symmetric interval of different altitudes in the Martian atmosphere based on the energy decay of the Mars probe in each symmetric interval and the atmospheric density inversion formula, where the atmospheric density inversion formula is expressed as: ρ represents the average atmospheric density in each symmetric interval of different altitudes in the Martian atmosphere, and ΔE represents the energy decay of the Mars probe in each symmetric interval. represents the work done by the solar radiation pressure, and C D is the drag coefficient, A is the windward area of the probe, m is the mass of the Mars probe, v represents the running speed of the Mars probe, and Δt represents the time difference of the Mars probe passing through each symmetric interval.

[0070] Specifically, when the Mars probe is operating in the Mars exploration orbit, it is affected by the gravitational force of the celestial body center and other perturbing forces. Here, the perturbing forces are divided into conservative perturbing forces and non-conservative perturbing forces. The mechanical energy of the probe is conserved under the action of conservative forces, while non-conservative forces change the mechanical energy. For a Mars-orbiting probe, the non-conservative forces are mainly atmospheric drag and radiation pressure perturbing force. The radiation pressure perturbing force can be accurately calculated through the radiation pressure model. Therefore, the atmospheric density of Mars can be inverted by calculating the energy decay of the probe. The total energy of the Mars probe in the Mars-fixed coordinate system can be expressed as Equation (1).

[0071]

[0072] Among them, represents the kinetic energy of the probe, V S and V M represent the gravitational potential energies of the sun and Mars, represents the rotational potential energy generated by the rotation of Mars, ω is the angular velocity of Mars' rotation, (x, y) represents the position coordinates of the Mars probe, and E n represents the work done by non-conservative forces. E n can be expressed as the integral of atmospheric drag and solar radiation pressure along the Mars exploration orbit path, as shown in Equation (2).

[0073] E n = ∫f drag · vdt + ∫f solar · vdt (2)

[0074] The work done by non-conservative forces in a certain time period is equal to the change in the mechanical energy of the probe. Denote the mechanical energies of the probe at times t 0 and t 1 as E 0 and E 1 respectively. In the time interval Δt = t 1 - t 0 the work done by non-conservative forces is E1 -E 0 , where the work done by atmospheric resistance can be expressed as formula (3), C D is the atmospheric drag coefficient.

[0075]

[0076] Finally, substituting equation (3) into equation (1), the inversion formula of the Martian atmospheric density can be expressed as equation (4). In the perigee region, the Martian atmospheric density is about 0.5 to 4 kg / km 3 , A is the windward area of ​​the detector, which belongs to the transitional flow field of rarefied gas. The drag coefficient C is calculated using Monte Carlo simulation and free molecular flow method. D About 2.13.

[0077]

[0078] Combined with formula (4), after calculating the energy attenuation of the Mars probe in each highly symmetrical interval of the Martian atmosphere, the energy attenuation value is entered into formula (4) to invert the average atmospheric density in each highly symmetrical interval of the Martian atmosphere, that is, ρ represents the average atmospheric density in each highly symmetrical interval of the Martian atmosphere, ΔE represents the energy attenuation of the Mars probe in each highly symmetrical interval, represents the work done by sunlight pressure, C D is the drag coefficient, A is the windward area of ​​the probe, m is the mass of the Mars probe, v represents the running speed of the Mars probe, and Δt represents the time difference for the Mars probe to pass through each highly symmetrical interval.

[0079] Based on the above steps S103 and S104, Figure 3 As shown, the time of near-fire is determined as t p , near-fire height h p ,The first step is to find the orbit height h before and after the perigee 1 Corresponding to time t 1 and t' 1 , calculate the corresponding detector energy E 1 and E′ 1 , according to the energy decay ΔE 1 =E 1 -E 1 'Calculate twice through h 1 The energy decay at t p Height at time h p The density at p ; The second step, in [t 1 , t' 1 ] Find the next orbital height h outside the interval 2 Corresponding to time t 2and t' 2 , calculate the corresponding detector energy E 2 and E' 2 , t 2 to t' 2 The energy attenuation is ΔE 2 = E 2 - E'', thus, according to the principle of high symmetry, the energy attenuation from t 2 to t 1 is Invert the average density ρ 21 in the range of h 1 - h 2 according to ΔE 12 ; In the third step, repeat the second step, continuously search for the next orbital height h i outside the interval [t i , t'], until the orbital height reaches the preset height threshold, then stop the inversion. Through the above steps, the atmospheric density in the height ranges of h i+1 , h p , h 1 - h 2 , h 2 - h 3 , ……, h n-1 - h n can be inverted.

[0080] Step S105, reduce the average atmospheric density in each height symmetry interval to a specific height position to obtain the atmospheric density at each height position in the Martian atmosphere.

[0081] The height symmetry method uses the energy attenuation twice within a height symmetry interval to invert the average atmospheric density in this height symmetry interval, and the inversion resolution can be significantly improved. However, there are still two problems: First, the inversion result only represents the average atmospheric density in a certain height range. Since the atmospheric density changes rapidly with height, the physical meaning of the average atmospheric density along the height is not clear; Second, when calculating the energy attenuation in an interval, it depends on the orbital accuracy at the end points of the interval, and all the orbital data within the interval are not fully utilized. To solve these two problems, in the above step S105, after successfully inverting and calculating the average atmospheric density of the Mars detector in each height symmetry interval, by reducing the average atmospheric density to a specific height position, the problem of the ambiguous physical meaning of the average density value is effectively solved, and the spatio-temporal resolution and accuracy of the atmospheric density inversion result are significantly improved.

[0082] Specifically, through a Mars atmosphere model, such as MarsGram, the atmospheric density of a Mars probe at each specific altitude within a height-symmetric interval is calculated point by point. Then, the point closest to the average atmospheric density value of the height-symmetric interval is selected, and the average atmospheric density of the height-symmetric interval is reduced to a specific altitude position to obtain the atmospheric density at each altitude position in the Mars atmosphere.

[0083] Optionally, the step of reducing the average atmospheric density within each height-symmetric interval to a specific altitude position includes: selecting multiple detection points within each height-symmetric interval; calculating the atmospheric density of each detection point based on the relative atmospheric density formula; calculating the difference in atmospheric density between the atmospheric density of each detection point and the average atmospheric density of the height-symmetric interval, and selecting the detection point with the smallest difference in atmospheric density as the target detection point for the height-symmetric interval; reducing the average atmospheric density within the height-symmetric interval to the altitude position corresponding to the target detection point of the height-symmetric interval.

[0084] It should be noted that in the embodiments of the present invention, a relative atmospheric density formula is defined, and the atmospheric density at each altitude position can be calculated through the relative relationship between each position. Specifically, within each height-symmetric interval, multiple detection points are evenly selected, and these points should cover the entire height range of the interval to ensure that there are enough data points within the height-symmetric interval for accurate comparison and to avoid reduction errors caused by improper selection of point positions. Based on the relative atmospheric density formula, the altitude position and atmospheric density at the periapsis are used as reference values to calculate the atmospheric density value corresponding to each selected detection point. The relative atmospheric density formula takes into account factors such as the variation of the gravitational field with altitude, atmospheric composition, and temperature, and can more accurately predict the atmospheric density at a specific altitude. This step provides a data basis for subsequent calculation of the difference in atmospheric density.

[0085] Furthermore, the calculated atmospheric density values of each detection point are compared with the average atmospheric density value within the height-symmetric interval, and the difference between the two is calculated. The detection point with the smallest difference in atmospheric density is selected as the target detection point for the height-symmetric interval. Through quantitative analysis of the difference, it is ensured that the altitude position of the target detection point can most accurately reflect the characteristics of the average atmospheric density, improving the accuracy of the reduction process.

[0086] Optionally, the relative atmospheric density formula is expressed as: where ρ 0 and ρ z are the atmospheric densities at altitudes z 0 and z respectively, m is the average molecular mass, g is the acceleration due to gravity, R is the ideal gas constant, and T is the temperature.

[0087] Finally, the relative atmospheric density formula uses the height position of a known atmospheric density as a reference point. According to the height position and atmospheric density of the reference point, the atmospheric density of each detection point can be calculated, which is specifically expressed as: The above ρ 0 and ρ z are the atmospheric densities at heights z 0 and z respectively (ρ 0 can select the periapsis), m is the average molecular mass, g is the acceleration due to gravity, R is the ideal gas constant, and T is the temperature.

[0088] By reducing the average atmospheric density within the height symmetric interval to a specific height position, when calculating the average atmospheric density on the Martian surface in the present invention, not only the orbital accuracy of the interval endpoints within the height symmetric interval of the Martian atmosphere is considered, but also the orbital data at all times within the height symmetric interval are fully utilized, enhancing the stability and reliability of the inversion result. It overcomes the problem of unclear physical meaning of the average density in traditional inversion methods and provides density data with clear physical meaning for the orbital design and control of spacecraft.

[0089] Through the above steps, monitor the operating state of the Mars probe in the Mars exploration orbit, collect the operating data of the Mars probe, and draw an operating diagram of the Mars probe based on the operating data. Among them, the height position of the periapsis and multiple height symmetric intervals of the Mars atmosphere are marked on the operating diagram. Then, using the height symmetry principle and based on the operating data, calculate the energy decay due to atmospheric drag of the Mars probe at the periapsis and within each height symmetric interval on the operating diagram, and invert the average atmospheric density within each height symmetric interval of the Mars atmosphere based on the energy decay. Finally, reduce the average atmospheric density within each height symmetric interval to a specific height position to obtain the atmospheric density at each height position of the Mars atmosphere.

[0090] In this embodiment, the operating data of the Mars probe in the Mars exploration orbit are collected in real time, and the atmospheric density of Mars is inverted according to the real-time operating data. When inverting the atmospheric density of Mars, the height symmetry method is adopted, which can invert the atmospheric density within a shorter time interval and a smaller height range, achieving the purpose of improving the height resolution of atmospheric density inversion, obtaining the technical effect of improving the measurement and control accuracy of the Martian atmospheric density, and thus solving the technical problem of low measurement and control accuracy in the related art when inverting the Martian atmospheric density by expanding the inversion time interval.

[0091] The following is a detailed description in combination with another optional specific implementation manner.

[0092] The embodiment of the present invention proposes an atmospheric density inversion method that can be widely applied to various types of orbits, which can improve the spatio-temporal resolution and accuracy of atmospheric density inversion.Figure 4 It is a schematic diagram of an optional inversion process of the Martian atmospheric density according to an embodiment of the present invention. As Figure 4 shown, the inversion process of the Martian atmospheric density specifically includes:

[0093] Step 1, calculate the energy attenuation of the detector due to atmospheric drag;

[0094] When the Mars detector operates in the Mars exploration orbit, it is affected by the gravitational force of the celestial body center and other perturbing forces. These perturbing forces are divided into conservative perturbing forces and non-conservative perturbing forces. The mechanical energy of the detector is conserved under the action of conservative forces, while non-conservative forces change the mechanical energy. For a Mars-orbiting detector (i.e., a Mars detector), the non-conservative forces are mainly atmospheric drag and radiation pressure perturbing force. The radiation pressure perturbing force can be accurately calculated through the radiation pressure model. Therefore, the Martian atmospheric density can be inverted by calculating the energy attenuation of the detector. The total energy of the detector can be expressed by Equation (1) in the Mars-fixed coordinate system.

[0095]

[0096] Among them, represents the kinetic energy of the detector, V S and V M represent the gravitational potential energies of the sun and Mars, represents the rotational potential energy generated by the rotation of Mars, ω is the angular velocity of Mars' rotation, (x, y) represents the position coordinates of the Mars detector, and E n represents the work done by non-conservative forces. E n can be expressed as the integral of atmospheric drag and solar light pressure along the orbital path (Mars exploration orbital path), as shown in Equation (2).

[0097] E n =∫f drag ·vdt + ∫f solar ·vdt (2)

[0098] The work done by non-conservative forces during a certain time period is equal to the change in the mechanical energy of the detector. Denote the mechanical energies of the detector at times t 0 and t 1 as E 0 and E 1 respectively. In the time interval Δt = t 1 -t 0 , the work done by non-conservative forces is E 1 -E 0 , where the work done by atmospheric drag can be expressed by Equation (3), and C D is the atmospheric drag coefficient.

[0099]

[0100] Therefore, substituting Equation (3) into Equation (1), the atmospheric density can be written as Equation (4). In the perigee region, the Martian atmospheric density is approximately 0.5 - 4 kg / km 3 , where A is the windward area of the detector, belonging to the transitional flow regime of rarefied gas. The drag coefficient C is calculated using the Monte Carlo simulation and free molecular flow method D which is approximately 2.13.

[0101]

[0102] Step 2: Invert the average atmospheric density within a certain altitude symmetric interval using the altitude symmetry method;

[0103] In Equation (4), ρ represents the average atmospheric density on the satellite path within the time interval Δt. The selection of Δt depends on the orbital accuracy of the detector and the magnitude of ρ itself. That is, the larger ρ is, the higher the orbital accuracy, and the smaller the value of Δt can be. Since the Martian atmosphere is extremely rarefied above 300 km, the energy of the detector only changes when it passes near the perigee, and the time for the detector to pass through the perigee is very short. Taking MAVEN as an example, the time for each orbit to operate below 300 km is only 700 - 900 s. According to the non-conservative force energy consumption formula (2), the shorter the force application time, the smaller the energy consumption generated. Therefore, when using the traditional method to invert the atmospheric density at the perigee, only by increasing the integration interval [t 1 , t 2 can a more accurate energy decay be obtained, resulting in a height resolution of the inversion result reaching several tens of kilometers and a relatively low inversion accuracy. Since the atmospheric density changes rapidly with altitude, the average atmospheric density within a relatively large altitude symmetric interval loses its physical meaning and engineering application value. To improve the inversion resolution, the embodiments of the present invention propose to invert the atmospheric density of a certain altitude symmetric interval based on the altitude symmetry principle by using the two energy decays in the same altitude symmetric interval.

[0104] When the detector passes near the perigee, the orbital altitude changes rapidly, while the changes in latitude and longitude are relatively small. As Figure 3 shown, there are two time intervals [t 2 , t 1 and [t' 1 , t' 2 before and after passing through the perigee. The corresponding altitude change range of the detector is [h 1 , h 2 , and the corresponding average atmospheric densities are almost equal, and the energy decays caused by atmospheric drag are also almost the same. Therefore, the average atmospheric density of this altitude range can be inverted by using the two energy decays of the detector within the two time intervals and the same altitude range, which can significantly improve the height resolution of the inversion result.

[0105] Figure 5It is a schematic diagram of an optional inversion process based on a highly symmetric inversion according to an embodiment of the present invention. As Figure 5 shown, the inversion process of the Martian atmosphere based on the highly symmetric method includes:

[0106] In the first step, determine that the periapsis time is t p , and the periapsis altitude is h p ;

[0107] In the second step, calculate the energy attenuation ΔE 1 within the range of [h p h 1 h’ 1 = E 1 - E′ 1 , and calculate the energy attenuation ΔE 2 within the range of [h p h 2 h’ 2 = E 2 - E 2 ′;

[0108] Find the corresponding times t 1 and t’ 1 at the orbital altitudes h 1 before and after the periapsis, calculate the corresponding detector energies E 1 and E′ 1 , and calculate the energy attenuation at h 1 = E 1 - E 1 ′ for the two passes through h 1 . Invert the density ρ p at the altitude h p at time t p .

[0109] Outside the interval [t 1 , t’ 1 , find the next orbital altitude h 2 corresponding to the times t 2 and t’ 2 , calculate the corresponding detector energies E 2 and E′ 2 . The energy attenuation from t 2 to t’ 2 is ΔE 2 = E 2 - E′ 2 . Thus, according to the principle of high symmetry, the energy attenuation from t 2 to t 1 is Invert h 21 - h 1 - h 2Average atmospheric density ρ within a highly symmetric interval 12 (i.e., );

[0110] Step 3: Repeat Step 2 to calculate the energy attenuation ΔE within the range of [h i-1 h p h’ i-1 , where ΔE i-1 = E i-1 - E′ i-1 , and calculate the energy attenuation ΔE within the range of [h i h p h’ i , where ΔE i = E i - E′ i ;

[0111] Repeat the above steps to continuously find the next orbital altitude h outside the interval of [t i , t’ i until the orbital altitude reaches the preset altitude threshold (illustrated by h i+1 > 300 km in Figure 5 ), then stop the inversion. Through the above steps, the atmospheric density within the altitude range of h i+1 , h p - h 1 , h 2 - h 2 , ……, h 3 - h n-1 - h n can be inverted.

[0112] Step 3: Reduce the average atmospheric density within a certain altitude-symmetric interval to a certain altitude.

[0113] The altitude-symmetric method uses the energy attenuation twice within an altitude-symmetric interval to invert the average atmospheric density within this interval, and the inversion resolution can be significantly improved. However, there are still two problems: First, the inversion result only represents the average atmospheric density within a certain altitude range. Since the atmospheric density changes rapidly with altitude, the physical meaning of the atmospheric density averaged along the altitude is not clear; Second, when calculating the energy attenuation within an interval, it depends on the orbital accuracy at the endpoints of the interval, and all the orbital data within the interval are not fully utilized. To solve these two problems, the embodiments of the present invention propose a method for reducing the average atmospheric density within an altitude-symmetric interval and the average energy of the spacecraft to a fixed altitude.

[0114] The distribution of the atmospheric density with altitude is mainly controlled by the gravity field and decreases exponentially with increasing altitude, as shown in Equation (5), where ρ 0 and ρ z are the atmospheric densities at altitudes z 0The atmospheric density at z, m is the average molecular mass, g is the acceleration due to gravity, R is the ideal gas constant, and T is the temperature.

[0115]

[0116] While the detector orbit altitude varies within a certain range, it also includes small-scale variations in latitude and local time. The empirical atmospheric model also considers the variation of atmospheric density with latitude and local time based on this formula. Therefore, it is considered that although the empirical atmospheric model cannot give the accurate absolute value of atmospheric density, it can accurately describe its variation trend within a certain symmetric altitude range. Thus, the following formula holds. There is a point h within the altitude symmetric range [h 1 , h 2 where the atmospheric model density at this point is equal to the average value of the atmospheric model density in the range [h 0 , h 1 , h 2 . At the same time, the average atmospheric density inverted in the range [h 1 , h 2 can represent the inverted value of the atmospheric density at h 0 , as shown in Equation (6).

[0117]

[0118] The specific calculation process is shown in the figure. First, use the atmospheric model MarsGram to calculate the atmospheric density ρ 1 , h 2 on the detector trajectory within the range [h mi point by point; then, according to the average atmospheric density ρ 1 , h 2 within the range [h 12 ; next, find the value closest to ρ mi in ρ 12 , and the corresponding altitude is denoted as h 0 ; finally, it is considered that the average atmospheric density ρ 1 , h 2 inverted by the energy attenuation in the interval represents the atmospheric density value at h 12 , h 0 .

[0119] In the embodiments of the present invention, through the altitude symmetry principle, the Martian atmospheric density is inverted within a shorter time interval and a smaller altitude range, so that the altitude resolution of the atmospheric density inversion is significantly improved, and a more detailed atmospheric density altitude profile can be provided, thereby improving the measurement and control accuracy and the accuracy of the measurement and control results.

[0120] In the embodiments of the present invention, by accurately calculating the energy attenuation of the detector on the large elliptical orbit due to atmospheric drag, this solution can more accurately reflect the influence of atmospheric density on the aircraft, thereby improving the accuracy of the inverted density value.

[0121] When calculating the average atmospheric density on the surface of Mars in the embodiments of the present invention, not only the orbital accuracy of the interval endpoints within the highly symmetric interval of the Mars atmosphere is considered, but also the orbital data at all times within the highly symmetric interval are fully utilized, enhancing the stability and reliability of the inversion result. At the same time, by reducing the average atmospheric density to a fixed altitude, the problem of unclear physical meaning of the average density in the traditional inversion method is overcome, providing density data with clear physical meaning for the orbital design and control of spacecraft.

[0122] A detailed description will be given below in combination with another embodiment.

[0123] Embodiment 2

[0124] An inversion device for the atmospheric density of Mars provided in this embodiment includes a plurality of implementation units. Each implementation unit corresponds to each implementation step in Embodiment 1 above. The specific implementation manner and beneficial effects can refer to the foregoing method embodiment and will not be elaborated here.

[0125] Figure 6 is a schematic diagram of an optional inversion device for the atmospheric density of Mars according to the embodiments of the present invention. As Figure 6 shown, the inversion device for the atmospheric density of Mars may include: an acquisition unit 61, a plotting unit 62, a calculation unit 63, an inversion unit 64, and a reduction unit 65, where

[0126] The acquisition unit 61 is configured to monitor the operating state of the Mars detector in the Mars exploration orbit and acquire the operating data of the Mars detector;

[0127] The plotting unit 62 is configured to plot an operating diagram of the Mars detector based on the operating data, where the height position of the periapsis and multiple highly symmetric intervals of the Mars atmosphere are marked in the operating diagram;

[0128] The calculation unit 63 is configured to utilize the principle of high symmetry and calculate the energy attenuation of the Mars detector due to atmospheric drag at the periapsis and within each highly symmetric interval on the operating diagram based on the operating data;

[0129] The inversion unit 64 is configured to invert the average atmospheric density within each highly symmetric interval of the Mars atmosphere based on the energy attenuation;

[0130] The reduction unit 65 is configured to reduce the average atmospheric density within each highly symmetric interval to a specific height position to obtain the atmospheric density at each height position of the Mars atmosphere.

[0131] The above-mentioned device for inverting the density of the Martian atmosphere monitors the operating state of a Mars probe in a Mars exploration orbit through an acquisition unit 61, and acquires the operating data of the Mars probe; a plotting unit 62 plots an operating graph of the Mars probe based on the operating data, wherein the height position of the periapsis and multiple height symmetry intervals of the Martian atmosphere are marked on the operating graph; a calculation unit 63 uses the height symmetry principle and calculates the energy attenuation due to atmospheric drag of the Mars probe at the periapsis and within each height symmetry interval on the operating graph based on the operating data; an inversion unit 64 inversely calculates the average atmospheric density within each height symmetry interval of the Martian atmosphere based on the energy attenuation; and a reduction unit 65 reduces the average atmospheric density within each height symmetry interval to a specific height position to obtain the atmospheric density at each height position of the Martian atmosphere.

[0132] In this embodiment, the operating data of the Mars probe in the Mars exploration orbit is collected in real time, and the density of the Martian atmosphere is inversely calculated according to the real-time operating data. When inversely calculating the density of the Martian atmosphere, the height symmetry method is adopted, which can inversely calculate the atmospheric density within a shorter time interval and a smaller height range, achieving the purpose of improving the height resolution of the atmospheric density inversion, obtaining the technical effect of improving the measurement and control accuracy of the Martian atmosphere density, and further solving the technical problem of relatively low measurement and control accuracy in the related art when inversely calculating the density of the Martian atmosphere by expanding the inversion time interval.

[0133] Optionally, the device for inverting the density of the Martian atmosphere further includes: a first determination module, configured to determine the height position of the periapsis and the flight moment when the Mars probe passes through the periapsis based on the flight trajectory in the operating graph; a first division module, configured to divide the operating graph with the height position of the periapsis as the reference position to obtain multiple height symmetry intervals and the corresponding end-point flight moments of each height symmetry interval, wherein the periapsis is the lowest point of the operating graph, the operating graph is symmetrically distributed on both sides with the periapsis as the center, and the height value of the maximum height of the height symmetry interval is less than or equal to a preset height threshold.

[0134] Optionally, the calculation unit includes: a second determination module for determining the minimum height and the maximum height of each highly symmetric interval; a first calculation module for calculating the energy decay of the Mars probe when passing through the minimum height twice in the highly symmetric interval to obtain a first energy decay; a second calculation module for calculating the energy decay of the Mars probe when passing through the maximum height twice in the highly symmetric interval to obtain a second energy decay; and a third calculation module for calculating the difference between the first energy decay and the second energy decay by using the highly symmetric principle, and obtaining the energy decay of the Mars probe in each highly symmetric interval based on the difference, where the highly symmetric principle means that when the Mars probe operates on the Mars exploration orbit, it will pass through each highly symmetric interval twice, and the energy decays of the two passes through the same highly symmetric interval are equal, and the average value of the energy decays of the two passes through the same highly symmetric interval is used as the energy decay of the Mars probe in this highly symmetric interval.

[0135] Optionally, the first calculation module includes: a first acquisition sub-module for determining the two end-point flight times corresponding to passing through the minimum height twice in the operation graph, and acquiring the operation data of the Mars probe at each end-point flight time; a first calculation sub-module for calculating the energy values of the Mars probe at each end-point flight time based on the operation data of the Mars probe at each end-point flight time and the energy calculation formula; and a second calculation sub-module for calculating the difference between the energy values of the Mars probe at the two end-point flight times to obtain the energy decay of the Mars probe when passing through the minimum height twice in the highly symmetric interval, and obtaining a first energy decay.

[0136] Optionally, the energy calculation formula is expressed as: where m represents the mass of the probe, v represents the velocity of the probe, x and y represent the position of the probe, and ω is the angular velocity of Mars' rotation, represents the kinetic energy of the probe, V S and V M represent the gravitational potential energy of the sun and Mars on the probe, represents the rotational potential energy generated by Mars' rotation.

[0137] Optionally, the inversion unit includes: a fourth calculation module for inverting the average atmospheric density in each highly symmetric interval of the Mars atmosphere based on the energy decay of the Mars probe in each highly symmetric interval and the atmospheric density inversion formula, where the atmospheric density inversion formula is expressed as: ρ represents the average atmospheric density in each highly symmetric interval of the Mars atmosphere, ΔE represents the energy decay of the Mars probe in each highly symmetric interval, represents the work done by the solar radiation pressure, C DCd is the drag coefficient, A is the frontal area of the detector, m is the mass of the Mars detector, v represents the running speed of the Mars detector, and Δt represents the time difference of the Mars detector passing through the symmetric intervals at each altitude.

[0138] Optionally, the reduction unit includes: a first selection module for selecting a plurality of detection points within each symmetric altitude interval; a fifth calculation module for calculating the atmospheric density of each detection point based on the relative atmospheric density formula; a second selection module for calculating the atmospheric density difference between the atmospheric density of each detection point and the average atmospheric density of the symmetric altitude interval, and selecting the detection point with the smallest atmospheric density difference as the target detection point of the symmetric altitude interval; a first reduction module for reducing the average atmospheric density within the symmetric altitude interval to the altitude position corresponding to the target detection point of the symmetric altitude interval.

[0139] Optionally, the relative atmospheric density formula is expressed as: where ρ 0 and ρ z are the atmospheric densities at altitudes z 0 and z respectively, m is the average molecular mass, g is the acceleration due to gravity, R is the ideal gas constant, and T is the temperature.

[0140] The above-mentioned Mars atmospheric density inversion device may further include a processor and a memory. The above-mentioned acquisition unit 61, drawing unit 62, calculation unit 63, inversion unit 64, reduction unit 65, etc. are all stored in the memory as program units, and the corresponding functions are implemented by the processor executing the above-mentioned program units stored in the memory.

[0141] The above-mentioned processor contains a kernel, and the kernel retrieves the corresponding program units from the memory. One or more kernels can be set, and the Mars atmospheric density is inverted by adjusting the kernel parameters.

[0142] The above-mentioned memory may include non-permanent memory in a computer-readable medium, forms such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash memory (flash RAM), and the memory includes at least one storage chip.

[0143] According to another aspect of the embodiments of the present invention, there is also provided a computer-readable storage medium. The computer-readable storage medium includes a stored computer program, wherein when the computer program runs, it controls the device where the computer-readable storage medium is located to execute any one of the above-mentioned Mars atmospheric density inversion methods.

[0144] According to another aspect of the embodiments of the present invention, there is also provided an electronic device, including one or more processors and a memory, where the memory is used to store one or more programs, and when the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the inversion method of the atmospheric density of Mars in any one of the above.

[0145] According to another aspect of the embodiments of the present invention, there is also provided a computer program product, the computer program product includes a computer program, and when the computer program is executed by a processor, the inversion method of the atmospheric density of Mars in any one of the above is implemented.

[0146] The present application also provides a computer program product, which is adapted to execute a program initialized with the following method steps when executed on a data processing device: monitoring the operating state of a Mars probe in a Mars exploration orbit and collecting the operating data of the Mars probe; drawing an operating diagram of the Mars probe based on the operating data, where the operating diagram marks the height position of the periapsis and multiple height symmetry intervals of the Mars atmosphere; using the height symmetry principle and calculating the energy attenuation of the Mars probe due to atmospheric drag at the periapsis and within each height symmetry interval on the operating diagram based on the operating data; inverting the average atmospheric density within each height symmetry interval of the Mars atmosphere based on the energy attenuation; and reducing the average atmospheric density within each height symmetry interval to a specific height position to obtain the atmospheric density at each height position of the Mars atmosphere.

[0147] The present application also provides a computer program product, which is adapted to execute a program initialized with the following method steps when executed on a data processing device: after drawing the operating diagram of the Mars probe based on the operating data, it further includes: determining the height position of the periapsis and the flight time when the Mars probe passes through the periapsis based on the operating trajectory in the operating diagram; taking the height position of the periapsis as a reference position, dividing the operating diagram into regions to obtain multiple height symmetry intervals and the corresponding end-point flight times of each height symmetry interval, where the periapsis is the lowest point of the operating diagram, the operating diagram is symmetrically distributed on both sides with the periapsis as the center, and the height value of the maximum height of the height symmetry interval is less than or equal to a preset height threshold.

[0148] The present application also provides a computer program product which, when executed on a data processing device, is adapted to execute a program initialized with the following method steps: The step of calculating the energy decay of the Mars probe due to atmospheric drag in each height symmetric interval on the operation graph based on the operation data includes: for each height symmetric interval, determining the minimum height and the maximum height of the height symmetric interval; calculating the energy decay of the Mars probe when passing through the minimum height twice in the height symmetric interval to obtain a first energy decay; calculating the energy decay of the Mars probe when passing through the maximum height twice in the height symmetric interval to obtain a second energy decay; using the height symmetry principle to calculate the difference between the first energy decay and the second energy decay, and obtaining the energy decay of the Mars probe in each height symmetric interval based on the difference, where the height symmetry principle means that when the Mars probe operates on the Mars exploration orbit, it will pass through each height symmetric interval twice, and the energy decays when passing through the height symmetric interval twice are equal, and using the average value of the energy decays when passing through the same height symmetric interval twice as the energy decay of the Mars probe in the height symmetric interval.

[0149] The present application also provides a computer program product which, when executed on a data processing device, is adapted to execute a program initialized with the following method steps: The step of calculating the energy decay of the Mars probe when passing through the minimum height twice in the height symmetric interval to obtain a first energy decay includes: determining the two endpoint flight times corresponding to passing through the minimum height twice in the operation graph, and obtaining the operation data of the Mars probe at each endpoint flight time; calculating the energy values of the Mars probe at each endpoint flight time based on the operation data of the Mars probe at each endpoint flight time and the energy calculation formula; calculating the difference between the energy values of the Mars probe at the two endpoint flight times, and obtaining the energy decay of the Mars probe when passing through the minimum height twice in the height symmetric interval, to obtain a first energy decay.

[0150] The present application also provides a computer program product which, when executed on a data processing device, is adapted to execute a program initialized with the following method steps: The energy calculation formula is expressed as: where m represents the mass of the probe, v represents the velocity of the probe, x and y represent the position of the probe, ω is the angular velocity of Mars' rotation, represents the kinetic energy of the probe, V S and V M represent the gravitational potential energy of the sun and Mars on the probe, represents the rotational potential energy generated by Mars' rotation.

[0151] The present application also provides a computer program product, which, when executed on a data processing device, is adapted to execute a program initialized with the following method steps: The step of inverting the average atmospheric density in each symmetric interval of different altitudes of the Martian atmosphere based on energy attenuation includes: calculating the average atmospheric density in each symmetric interval of different altitudes of the Martian atmosphere based on the energy attenuation of the Mars probe in each symmetric interval of different altitudes and the atmospheric density inversion formula, where the atmospheric density inversion formula is expressed as: ρ represents the average atmospheric density in each symmetric interval of different altitudes of the Martian atmosphere, and ΔE represents the energy attenuation of the Mars probe in each symmetric interval of different altitudes. represents the work done by the solar radiation pressure, and C D is the drag coefficient, A is the windward area of the probe, m is the mass of the Mars probe, v represents the running speed of the Mars probe, and Δt represents the time difference of the Mars probe passing through each symmetric interval of different altitudes.

[0152] The present application also provides a computer program product, which, when executed on a data processing device, is adapted to execute a program initialized with the following method steps: The step of reducing the average atmospheric density in each symmetric interval of different altitudes to a specific altitude position includes: selecting multiple detection points in each symmetric interval of different altitudes; calculating the atmospheric density of each detection point based on the relative atmospheric density formula; calculating the atmospheric density difference between the atmospheric density of each detection point and the average atmospheric density of the symmetric interval of different altitudes, and selecting the detection point with the smallest atmospheric density difference as the target detection point of the symmetric interval of different altitudes; reducing the average atmospheric density in the symmetric interval of different altitudes to the altitude position corresponding to the target detection point of the symmetric interval of different altitudes.

[0153] The present application also provides a computer program product, which, when executed on a data processing device, is adapted to execute a program initialized with the following method steps: The relative atmospheric density formula is expressed as: where ρ 0 and ρ z are the atmospheric densities at altitudes z 0 and z respectively, m is the average molecular mass, g is the acceleration due to gravity, R is the universal gas constant, and T is the temperature.

[0154] Figure 7 is a hardware structure block diagram of an electronic device (or mobile device) for implementing the method for inverting the Martian atmospheric density according to an embodiment of the present invention. As Figure 7 shown, the electronic device may include one or more processors ( Figure 7In the figure, 702a, 702b, ……, 702n are used to illustrate that the processor 702 may include, but is not limited to, a processing device such as a microprocessor MCU or a programmable logic device FPGA, and a memory 704 for storing data. In addition, it may further include: a display, an input / output interface (I / O interface), a universal serial bus (USB) port (which may be included as one of the ports of the I / O interface), a network interface, a keyboard, a power supply, and / or a camera. Those of ordinary skill in the art can understand that Figure 7 The structure shown is only schematic and does not limit the structure of the above-mentioned electronic device. For example, the electronic device may further include more or fewer components than those shown in Figure 7 the figure, or have a different configuration from that shown in Figure 7 the figure.

[0155] The serial numbers of the above-mentioned embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0156] In the above-mentioned embodiments of the present invention, the descriptions of the respective embodiments have their own emphases. For parts not detailed in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

[0157] In the several embodiments provided by the present application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only illustrative. For example, the division of the units can be a logical function division, and in actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces, and the indirect couplings or communication connections of the units or modules can be in electrical or other forms.

[0158] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0159] In addition, in each embodiment of the present invention, the functional units can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units.

[0160] When the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), mobile hard disks, magnetic disks, or optical discs.

[0161] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for inverting the density of the Martian atmosphere, characterized in that: include: Monitoring the operating status of the Mars probe in the Mars exploration orbit and collecting operating data of the Mars probe; Drawing an operation diagram of the Mars probe based on the operation data, wherein the height position of the perigee and the height symmetry intervals of multiple Martian atmosphere layers are marked in the operation diagram; Using the principle of height symmetry and based on the operation data, the energy attenuation of the Mars probe due to atmospheric drag at the perigee and in each height symmetry interval on the operation diagram is calculated; Inverting the average atmospheric density in each highly symmetrical interval of the Martian atmosphere based on the energy decay; The average atmospheric density within each of the highly symmetric intervals is converted to a specific altitude position to obtain the atmospheric density at each altitude position in the Martian atmosphere.

2. The method according to claim 1, characterized in that After drawing an operation diagram of the Mars probe based on the operation data, the method further includes: Determine the altitude position of the perigee and the flight time of the Mars probe passing through the perigee based on the operation trajectory in the operation diagram; Taking the height position of the near-fire point as the reference position, the operation diagram is divided into regions to obtain a plurality of highly symmetrical intervals and the endpoint flight times corresponding to each of the highly symmetrical intervals, wherein the near-fire point is the lowest point of the operation diagram, and the operation diagram is symmetrically distributed on both sides with the near-fire point as the center, and the height value of the maximum height of the highly symmetrical interval is less than or equal to a preset height threshold.

3. The method according to claim 1, characterized in that The step of calculating the energy attenuation of the Mars probe due to atmospheric drag in each highly symmetrical interval on the operation diagram based on the operation data comprises: For each of the highly symmetric intervals, determining a minimum height and a maximum height of the highly symmetric interval; Calculate the energy attenuation of the Mars probe passing through the minimum height twice in the height symmetry interval to obtain a first energy attenuation; Calculate the energy attenuation of the Mars probe passing through the maximum height twice in the height symmetry interval to obtain a second energy attenuation; The principle of height symmetry is used to calculate the difference between the first energy attenuation and the second energy attenuation, and the energy attenuation of the Mars rover in each height symmetry interval is obtained based on the difference. The principle of height symmetry means that when the Mars rover is operating on the Mars exploration orbit, it will pass through each height symmetry interval twice, and the energy attenuation of passing through the height symmetry interval twice is equal. The average value of the energy attenuation of passing through the same height symmetry interval twice is used as the energy attenuation of the Mars rover in the height symmetry interval.

4. The method according to claim 3, characterized in that: The step of calculating the energy attenuation of the Mars probe passing through the minimum height twice in the highly symmetric interval to obtain a first energy attenuation comprises: Determine the flight times of two endpoints corresponding to two passes through the minimum altitude in the operation diagram, and obtain the operation data of the Mars probe at each endpoint flight time; Calculating the energy value of the Mars probe at each endpoint flight time based on the operating data of the Mars probe at each endpoint flight time and the energy calculation formula; The difference in energy values ​​of the Mars probe at the two endpoints of the flight is calculated to obtain the energy attenuation of the Mars probe when it passes the minimum height twice in the highly symmetric interval, and the first energy attenuation is obtained.

5. The method according to claim 4, characterized in that The energy calculation formula is expressed as: Where m is the mass of the probe, v is the velocity of the probe, x and y are the positions of the probe, and ω is the angular velocity of Mars' rotation. represents the detector kinetic energy, V S and V M represents the gravitational potential energy of the Sun and Mars on the probe, Represents the rotational potential energy generated by Mars' rotation.

6. The method according to claim 1, characterized in that The step of inverting the average atmospheric density in each highly symmetrical interval of the Martian atmosphere based on the energy attenuation comprises: The average atmospheric density in each highly symmetrical interval of the Martian atmosphere is calculated based on the energy attenuation of the Mars probe in each highly symmetrical interval and the atmospheric density inversion formula, wherein the atmospheric density inversion formula is expressed as: ρ represents the average atmospheric density in each highly symmetrical interval of the Martian atmosphere, ΔE represents the energy attenuation of the Mars probe in each highly symmetrical interval, represents the work done by sunlight pressure, C D is the drag coefficient, A is the windward area of ​​the probe, m is the mass of the Mars probe, v represents the running speed of the Mars probe, and Δt represents the time difference for the Mars probe to pass through each highly symmetrical interval.

7. The method according to claim 1, characterized in that The step of converting the average atmospheric density in each of the highly symmetric intervals to a specific height position comprises: Selecting a plurality of detection points in each of the highly symmetric intervals; Calculate the atmospheric density at each detection point based on the relative atmospheric density formula; Calculate the atmospheric density difference between the atmospheric density of each detection point and the average atmospheric density of the highly symmetric interval, and select the detection point with the smallest atmospheric density difference as the target detection point of the highly symmetric interval; The average atmospheric density within the highly symmetric interval is converted to the height position corresponding to the target detection point within the highly symmetric interval.

8. The method according to claim 7, characterized in that The relative atmospheric density formula is expressed as: Among them, ρ0 and ρ z are the atmospheric densities at altitudes z0 and z respectively, m is the average molecular mass, g is the acceleration due to gravity, R is the ideal gas constant, and T is the temperature.

9. An inversion device for the density of the Martian atmosphere, characterized in that: include: A collection unit, used to monitor the operating status of the Mars probe in the Mars exploration orbit and collect operating data of the Mars probe; A drawing unit, configured to draw an operation diagram of the Mars probe based on the operation data, wherein the height position of the perigee and the height symmetry intervals of multiple Martian atmosphere layers are marked in the operation diagram; A calculation unit, for calculating the energy attenuation of the Mars probe due to atmospheric drag at the perigee and in each highly symmetrical interval on the operation diagram based on the operation data by using the highly symmetrical principle; An inversion unit, used for inverting the average atmospheric density in each highly symmetric interval of the Martian atmosphere based on the energy attenuation; The reduction unit is used to reduce the average atmospheric density in each of the highly symmetric intervals to a specific altitude position to obtain the atmospheric density at each altitude position in the Martian atmosphere.

10. An electronic device, characterized in that: It includes one or more processors and a memory, wherein the memory is used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the inversion method of the Martian atmosphere density as described in any one of claims 1 to 8.

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