CN117022678B

CN117022678B - Method, system, electronic device and medium for avoiding collision risk

Info

Publication number: CN117022678B
Application number: CN202311094534.0A
Authority: CN
Inventors: 陈倩茹; 唐歌实; 吴新林; 吴凌根; 何镇武; 吴琳琳
Original assignee: Emposat Co Ltd
Current assignee: Beijing Aerospace Yuxing Technology Co.,Ltd.
Priority date: 2023-08-29
Filing date: 2023-08-29
Publication date: 2024-01-26
Anticipated expiration: 2043-08-29
Also published as: CN117022678A

Abstract

The invention relates to the technical field of satellite orbit control, and provides a method, a system, electronic equipment and a medium for avoiding collision risk by combining a time avoidance method and a long-term orbit lifting strategy, wherein the method comprises the following steps: s1: acquiring an orbit control strategy, wherein the orbit control strategy is a scheme of igniting a plurality of circles of satellites in an electric pushing mode in a preset time period, and comprises the time length of each ignition; s2: acquiring collision risk of satellites adopting an orbit control strategy; s3: if the collision risk does not exist, executing the track control strategy; if there is a risk of collision: judging whether the duration of the ith ignition is 0 or not, if not, reducing the duration of the ith ignition in the track control strategy, otherwise, reducing the duration of the (i+1) th ignition in the track control strategy, wherein i=i+1, and forming a new track control strategy; s4: steps S2 to S3 are repeatedly performed until there is no risk of collision. The scheme can realize collision avoidance under the condition of reducing the influence on normal rail lifting task execution as much as possible.

Description

Method, system, electronic device and medium for avoiding collision risk

Technical Field

The invention relates to the technical field of satellite orbit control, in particular to a method, a system, electronic equipment and a medium for avoiding collision risks.

Background

Starting with the application of electric propulsion on communication satellites in the united states beginning in the 90 s of the 20 th century, the number of spacecraft in which electric propulsion was applied on-orbit has nearly doubled over the past 30 years, with the number of applications of space electric propulsion exceeding thousands of stations/suite. Whether or not to apply electric propulsion has become one of the important markers for measuring the technical advancement of satellite platforms. The space electric propulsion can be widely applied to tasks such as position maintenance, attitude control, orbit transfer and main propulsion of spacecraft such as communication satellites, remote sensing satellites, scientific experiment satellites, manned space stations and the like.

The electric propulsion technology is a satellite propulsion technology which utilizes electric energy to accelerate propulsion working medium so as to realize high specific impulse, and low propellant consumption caused by high specific impulse can improve the bearing capacity of effective load under the condition of constant take-off weight, and if the effective load is certain, the carrying capacity of the propellant can be increased so as to improve the service life of the satellite, or the total quality of the satellite can be directly reduced, and the emission cost can be saved.

The electric propulsion thrust is small, the thrust of a single thruster is between tens and hundreds millinewtons, the thrust of the single chemical thruster is only a few percent, and the thrust of the single chemical thruster is a few thousandths of an engine with a orbital transfer task. Because the electric propulsion spacecraft has limited capability, the influence of one-time ignition on the track change is small, the track change is insufficient to reach the target track, and the next ignition can be performed only by charging and energy supplementing for a period of time after one-time ignition process, the track control strategy of the electric propulsion spacecraft usually comprises a plurality of turns and multiple ignition, and is complex.

The prior art does not employ an electric propulsion method to avoid collision risk, and the prior art generally employs a chemical propulsion method to adjust the track height prior to a collision to avoid the collision. The method is a single orbit control adjustment strategy, the iteration of the strategy for calculating the increment range or the time range of the adjustable speed is complex, the method is suitable for the precise adjustment strategy of a single orbit control event, and the method is not suitable for a spacecraft for long-term orbit control execution. Moreover, the thrusters facing the prior art are pulse thrusters, and because the electric thrusters are limited in thrust, the influence of single ignition on track change is small, so that the adjustment of a single ignition strategy is possibly insufficient to avoid a risk target, and the electric thrusters are also not suitable for the spacecraft carrying the electric thrusters.

Therefore, a method, a system, electronic equipment and a medium for avoiding collision risk are needed to be provided, and an avoidance strategy and a control strategy can be fused together through an electric propeller in the process of lifting the track height for a long time, so that collision avoidance can be implemented under the condition that normal track lifting task execution is not affected, and the cost is greatly saved.

The above information disclosed in the background section is only for enhancement of understanding of the background of the application and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art.

Disclosure of Invention

The invention mainly aims to solve the problem that a normal control task is influenced by a single track lifting of a satellite in order to avoid collision, and provides a method, a system, electronic equipment and a medium for avoiding collision risk.

In order to achieve the above object, a first aspect of the present invention provides a method for avoiding collision risk by combining a time avoidance method and a long-term rail lifting strategy, including the following steps:

s1: acquiring an orbit control strategy, wherein the orbit control strategy is a scheme of igniting a plurality of circles of satellites in an electric pushing mode in a preset time period, and comprises the time length of each ignition;

s2: acquiring collision risk of satellites adopting an orbit control strategy;

s3: if the collision risk does not exist, executing the track control strategy; if there is a risk of collision: judging whether the duration of the ith ignition is 0 or not, if not, reducing the duration of the ith ignition in the track control strategy, otherwise, reducing the duration of the (i+1) th ignition in the track control strategy, wherein i=i+1, and the rest of the ignition strategies are kept unchanged to form a new track control strategy; i is a natural number greater than or equal to 1, and i is 1 in the first judgment;

s4: steps S2 to S3 are repeatedly performed until there is no risk of collision.

According to an exemplary embodiment of the present invention, in step S1, the time of each ignition of the satellite is equal in the orbit control strategy.

According to an exemplary embodiment of the present invention, in step S1, the orbit control strategy is a method of satellite ignition for a plurality of consecutive turns of the satellite within a predetermined period of time, each turn being ignited at a rising intersection and/or a falling intersection.

According to an example embodiment of the invention, the method of satellite ignition is consistent with the direction of satellite motion.

According to an exemplary embodiment of the present invention, in step S2, the acquiring the collision risk of the satellite adopting the orbit control strategy includes: and acquiring collision risks of the satellite adopting a control strategy according to the orbit control strategy of the satellite and ephemeris of other spacecrafts.

According to an exemplary embodiment of the present invention, in step S3, the duration of each reduced ignition is unchanged.

According to an exemplary embodiment of the present invention, in step S3, the ignition parameters and ephemeris after the ignition duration is reduced are recalculated before the new orbit control strategy is formed.

As a second aspect of the present invention, the present invention provides a system for adjusting a track control strategy, comprising:

the track control strategy making module is used for making a track control strategy; the orbit control strategy is a scheme that the satellite adopts satellite ignition in an electric pushing mode for a plurality of circles in a preset time period;

the collision risk prediction module is connected with the orbit control strategy assignment module and is used for calculating the collision risk of the satellite adopting the orbit control strategy according to the orbit control strategy;

the collision intervention module is connected with the track control strategy making module and the collision risk prediction module and is used for judging the collision risk and adjusting the ignition duration, and if the collision risk does not exist, the track control strategy is executed; if there is a risk of collision: judging whether the duration of the ith ignition is 0 or not, if not, reducing the duration of the ith ignition in the track control strategy, otherwise, reducing the duration of the (i+1) th ignition in the track control strategy, wherein i=i+1, and the rest of the ignition strategies are kept unchanged to form a new track control strategy; i is a natural number greater than or equal to 1, i is 1 when judging for the first time, and repeatedly judging collision risk and adjusting ignition duration until no collision risk exists;

the orbit control strategy executing module is connected with the orbit control strategy making module and the collision intervention module and used for executing the orbit control strategy.

As a third aspect of the present invention, the present invention provides an electronic apparatus comprising:

one or more processors;

a storage means for storing one or more programs;

the one or more programs, when executed by the one or more processors, cause the one or more processors to implement the electrically-driven adjustment of the tracking strategy.

As a fourth aspect of the present invention, the present invention provides a computer readable medium having stored thereon a computer program which when executed by a processor implements the electrically-driven adjustment of a tracking strategy.

The invention has the advantages that:

the method is suitable for adjusting the track control strategy of one batch for avoiding collision risk by lifting the track height of the high-frequency low-thrust electric propulsion spacecraft, well fuses the avoiding strategy with the control strategy, realizes the implementation of collision avoiding under the condition that the normal track lifting task execution is not influenced, and greatly saves the cost.

The method does not need to consider the position of the intersection target, and is also suitable for the situation that a plurality of collision risks occur or the situation that the ignition position of the original strategy is opposite to the intersection position.

The method is suitable for the situation that the collision early warning calculation false alarm rate is low, evading measures are adopted as soon as possible, and the influence of the adjusted track control strategy on the track control target is minimum.

The invention is also suitable for the track control condition that the lighting condition is strict or the eccentricity ratio in the track lifting process is strict and the ignition position cannot be adjusted.

The invention is also suitable for micro-cow electric thrusters or rail control strategies with longer single ignition time, and even if the latitude amplitude angle of each ignition before a risk circle is adjusted to be opposite to the intersection position, the risk situation can not be avoided.

Drawings

The above and other objects, features and advantages of the present application will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings. The drawings described below are only some embodiments of the present application and other drawings may be obtained from these drawings without inventive effort for a person of ordinary skill in the art.

Fig. 1 schematically shows a block diagram of a system for adjusting an orbit control strategy.

Fig. 2 schematically shows a step diagram of adjusting the orbit control strategy by means of electric pushing.

Fig. 3 schematically shows a flow chart for adjusting the orbit control strategy by means of electric pushing.

Fig. 4 schematically shows a graph of the intersection distance of ephemeris and risk targets over time for two adjustment schemes.

Fig. 5 schematically shows a block diagram of an electronic device.

Fig. 6 schematically shows a block diagram of a computer readable medium.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be embodied in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar parts, and thus a repetitive description thereof will be omitted.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the present application. One skilled in the relevant art will recognize, however, that the aspects of the application can be practiced without one or more of the specific details, or with other methods, components, devices, steps, etc. In other instances, well-known methods, devices, implementations, or operations are not shown or described in detail to avoid obscuring aspects of the application.

The block diagrams depicted in the figures are merely functional entities and do not necessarily correspond to physically separate entities. That is, the functional entities may be implemented in software, or in one or more hardware modules or integrated circuits, or in different networks and/or processor devices and/or microcontroller devices.

The flow diagrams depicted in the figures are exemplary only, and do not necessarily include all of the elements and operations/steps, nor must they be performed in the order described. For example, some operations/steps may be decomposed, and some operations/steps may be combined or partially combined, so that the order of actual execution may be changed according to actual situations.

It will be understood that, although the terms first, second, third, etc. may be used herein to describe various components, these components should not be limited by these terms. These terms are used to distinguish one element from another element. Thus, a first component discussed below could be termed a second component without departing from the teachings of the present application concept. As used herein, the term "and/or" includes any one of the associated listed items and all combinations of one or more.

Those skilled in the art will appreciate that the drawings are schematic representations of example embodiments, and that the modules or flows in the drawings are not necessarily required to practice the present application, and therefore, should not be taken to limit the scope of the present application.

According to a first embodiment of the present invention, the present invention provides a system for adjusting a tracking strategy, as shown in fig. 1, including:

the track control strategy making module 1 is used for making a track control strategy; the orbit control strategy is a scheme that the satellite adopts satellite ignition by adopting an electric pushing mode for a plurality of circles within a preset time period. The orbit control strategy is an orbit control strategy using an electric pushing mode. Because the electric propulsion thrust is small, the thrust of a single thruster is about tens to hundreds millinewtons, and is only a few percent of the thrust of a single chemical thruster and a few thousandths of an engine with a track-changing task; the track control strategy can be ignited at each circle, and the track can be achieved through accumulated adjustment of a plurality of circles after each ignition for a preset time.

The collision risk prediction module 2 is connected with the orbit control strategy assignment module 1 and is used for calculating the collision risk of the satellite adopting the orbit control strategy according to the orbit control strategy.

The collision intervention module 3 is connected with the track control strategy making module 1 and the collision risk prediction module 2 and is used for judging collision risk and adjusting the ignition duration, and if the collision risk does not exist, the track control strategy is executed; if there is a risk of collision: judging whether the duration of the ith ignition is 0 or not, if not, reducing the duration of the ith ignition in the track control strategy, otherwise, reducing the duration of the (i+1) th ignition in the track control strategy, wherein i=i+1, and the rest of the ignition strategies are kept unchanged to form a new track control strategy; i is a natural number greater than or equal to 1, i is 1 when judging for the first time, and repeatedly judging collision risk and adjusting ignition duration until no collision risk exists;

the orbit control strategy executing module 4 is connected with the orbit control strategy making module 1 and the collision intervention module 3 and is used for executing the orbit control strategy.

According to a second embodiment of the present invention, the present invention provides a method for avoiding collision risk in combination with a time avoidance method and a long-term lift rail strategy.

In the prior art, only collision avoidance strategies for pulse orbits are available. There are mainly two types: the short-term evasion strategy adopts a height separation method, namely, under the condition that the forecast time is relatively close, tangential velocity increment is applied by utilizing one pulse so as to increase the distance (radial distance) between the intersection collision time and the track height of the target, and obviously, the required velocity increment is relatively large; the middle-stage evasion strategy adopts a track separation method, namely a method for increasing tangential distance at the moment of intersection collision by utilizing a plurality of small speed increments in track direction when a longer time is from the intersection, and even if the middle-stage evasion strategy is staggered in time with a target, the intersection collision points which pass through simultaneously are changed into the sequential passing through.

According to different conditions of on-orbit operation of the spacecraft, the following three methods can be used for making collision avoidance strategies.

1. The height avoidance method comprises the following steps: the altitude evasion is that in the n+1/2 (n=0, 1,2 …) orbit ring before collision, a speed increment along the track direction is applied to the spacecraft to raise or lower the orbit altitude, so that a radial distance difference exists when the orbit altitude passes through the predicted collision point, and the orbit altitude evades collision with a dangerous object.

2. The time evading method comprises the following steps: in the time avoidance, in the orbit ring n (n is more than or equal to 2) before collision, a few small speed increments along the track direction are applied to the spacecraft, and the orbit height is raised or lowered, so that the moment when the orbit height passes through the predicted collision point is staggered, and the collision with a dangerous target is avoided.

3. The evasion strategy calculation method combined with the control strategy comprises the following steps: on the basis of not influencing the execution of the flight task of the spacecraft, the collision avoidance and the normal flight program of the spacecraft are combined, and the collision avoidance can be selected and carried out simultaneously with the normal orbit maneuver of the spacecraft, namely on the basis of the redundancy control quantity considered by normal control, the control time point of the control strategy or the speed increment along the track direction is subjected to smaller correction, so that the moment or the radial distance of the collision point is staggered, and the purpose of collision avoidance is achieved.

The scheme combines a time evading method and a long-term rail lifting strategy, and the main principle is as follows: on the basis of not influencing the execution of the flight tasks of the satellite (or other spacecrafts), the collision avoidance and the normal flight program of the satellite are combined, and the collision avoidance can be selected to be performed simultaneously with the normal orbit maneuver of the satellite, namely, on the basis of the redundancy control quantity considered by normal control, the control time point of the control strategy or the speed increment along the track direction is subjected to smaller correction, so that the moment or the radial distance of the collision point is staggered, and the purpose of collision avoidance is achieved.

The main method of the scheme is as follows: in the process of lifting the orbit height for a long time, the electric propeller iteratively reduces the ignition time length of the first circle by combining an avoidance strategy calculation method and a time avoidance method combined with the lifting orbit control strategy, namely reduces the speed increment of the first ignition, and carries out collision early warning again, so that the electric propulsion spacecraft can smoothly enter the target orbit.

The scheme is to orbit the low orbit satellite, and the satellite is controlled by the electric propeller to enter the target orbit. The continuous operation time of the electric propulsion is limited by the performance of the satellite-borne battery, and therefore requires a very high number of firings before the satellite enters the target orbit. To ensure that the satellite enters the target orbit, an orbit control strategy needs to be formulated, wherein the time, direction and thrust of each ignition of the satellite are formulated in detail. In order to ensure space safety, the orbit of the satellite needs to be forecasted for avoiding potential collision with other spacecrafts; when potential collision risk exists, the track control strategy needs to be adjusted, the track forecast is updated, and then collision risk assessment is carried out again; to ensure that satellites enter the target orbit while avoiding collision risks. The duration of the track control stage is long, and as the prediction error is accumulated along with time, the calculation of the collision risk needs to be continuously re-tracked and corrected after the track control implementation process, the common track control strategy needs to calculate the collision risk in batches, and one batch comprises multiple ignition.

As shown in fig. 2 and 3, the method for avoiding collision risk by combining the time avoidance method and the long-term lift rail strategy specifically includes the following steps:

s1: and acquiring an orbit control strategy, wherein the orbit control strategy is a scheme of igniting a satellite in a plurality of circles in an electric pushing mode within a preset time period, and comprises the time length of each ignition.

The orbit control strategy is a method for satellite ignition of a plurality of continuous circles of satellites in a preset time period, each circle of satellites is ignited at an intersection point and/or an intersection point, and the satellite ignition method is consistent with the satellite movement direction. In the orbit control strategy, the time of each ignition of the satellite is equal, and the time is t.

The rail control strategy also includes the direction and thrust of each firing. The orbit control strategy can be an inclination angle orbit control strategy or a height orbit control strategy.

The existing collision early warning calculation technology is very dependent on the accuracy of space target orbit determination prediction, and the larger the prediction position error is, the higher the collision probability is. For a normally operated satellite (or other spacecrafts), the control unit can carry out precise orbit determination and prediction on the satellite (or other spacecrafts) to acquire precise ephemeris data; but for spacecraft and space debris in other countries, it is difficult to obtain accurate ephemeris data. If the collision risk cannot be calculated by using the precise ephemeris of two space targets, the false alarm rate of the collision early warning for a long time in the future is very high. For example, a collision warning event after 2 days, there is no risk if no collision measure is taken to update the track recalculation after 1 day. Due to the practical factor, when the precise track data of the collision risk target is inaccurate, avoidance measures are not adopted too early, so that waste of fuel, manpower and the like is caused. However, if the precise ephemeris of two space targets can be obtained, the reliability of collision risk targets is high, the false alarm rate is low, and evasion measures can be taken early. Particularly, the earlier the avoidance strategy using the time avoidance method is, the smaller the speed increment adjustment amount for the avoidance is. For electric propulsion, the original track control strategy is generally track control according to the maximum allowed ignition time, the ignition time is reduced as required for avoiding, and the shorter the reduced ignition time is, the shorter the time to reach the target track is.

Thus, an orbit control strategy is a batch of orbit control strategies for a satellite over a predetermined period of time.

S2: and acquiring collision risk of the satellite adopting an orbit control strategy.

The acquiring collision risk of the satellite adopting the orbit control strategy comprises the following steps: and acquiring collision risks of the satellite adopting a control strategy according to the orbit control strategy of the satellite and ephemeris of other spacecrafts.

S3: if the collision risk does not exist, executing the track control strategy; if there is a risk of collision: judging whether the duration of the ith ignition is 0 or not, if not, reducing the duration of the ith ignition in the track control strategy, otherwise, reducing the duration of the (i+1) th ignition in the track control strategy, wherein i=i+1, and the rest of the ignition strategies are kept unchanged to form a new track control strategy; i is a natural number greater than or equal to 1, and i is 1 at the first judgment.

The duration of each reduced ignition is unchanged and is deltat. Δt depends on the actual parameters of the thruster and the orbit control strategy. Preferably, Δt is 30% -50% of the duration of a single firing in the rail control strategy.

The ignition parameters and ephemeris after decreasing the ignition duration are recalculated before the new orbit control strategy is formed. The orbit of the satellite is different from the original orbit control strategy due to the change of the front ignition parameters, the arrival time of the satellite at a remote place is different, and the back ignition parameters are different, so that recalculation is needed. But this strategy is unchanged, for example, by firing at a remote location for a predetermined time (e.g., 3000 s).

A rail control strategy is executed that does not present a risk of collision.

The advantages of this solution are demonstrated in particular by the following examples:

satellite orbit parameters (J2000 coordinate system):

epoch (UTCG)	8May 2023 04:00:00.000UTCG
		Semi-long axis (m)	6878140
Eccentricity ratio	0.0020000
		Inclination angle (deg)	97.4
Intersection point of rising red meridian (deg)	200
		Near-site argument (deg)	0
Flat angle (deg)	0

Total weight of satellites: 50kg;

thrust: 0.3mN;

energy constraint: at most 3000s per turn.

One batch of the orbit control strategy was 3 days.

Risk target track:

epoch (UTCG)	8May 2023 04:00:00.000UTCG
		Semi-long axis (m)	7376125
Eccentricity ratio	0.117619
		Inclination angle (deg)	95.360
Intersection point of rising red meridian (deg)	245.698
		Near-site argument (deg)	39.413
Flat angle (deg)	269.902

The original track control strategy is that the ignition is carried out for 3000s along the speed direction near each circle of far points.

The satellite will meet the risk target at 2023-05-11:09:00, the meeting location being at a 90 deg. latitude angle of magnitude, the meeting distance being 0.299km.

Since the collision probability of the pre-warning is closely related to the minimum distance between the spacecraft and the dangerous target at the closest moment (Time of Closest Approach, TCA), the embodiment takes the minimum distance of 2km at the closest moment as a threshold.

According to the height avoidance method, even if the position of each ignition is adjusted to 270 ° (the intersection position is 180 ° opposite to the phase), the minimum distance intersection distance at the closest timing is 0.537km, less than 2km, and risks cannot be avoided.

The height avoidance method comprises the following steps: the altitude evasion is that in m+1/2 (m=0, 1,2 …) orbit circles before collision, a speed increment along the track direction is applied to the spacecraft to raise or lower the orbit altitude, so that a radial distance difference exists when the orbit altitude passes through the expected collision point, and collision with an intersection target is avoided. m represents the collision risk circle. Along the track direction refers to along the satellite motion direction.

The altitude avoidance method needs to be ignited at a specified latitude angle of the opposite phase at the intersection position, and the altitude avoidance method for ignition at the specified latitude angle is limited and is not applicable in many cases. The constraints of different spacecrafts on energy sources are different, the constraints of the different spacecrafts on orbit parameters in the orbit raising process are different, for example, some electric thrusters carried by the spacecrafts can only work in an illumination area; some have strict requirements on the eccentricity in the track lifting process; some can only fire at a certain latitude argument or a certain position; if a plurality of collision risk targets appear, the situation height avoidance method such as inconsistent meeting positions is not applicable. For micro-bovine electric thrusters, the risk may not be circumvented even if the latitude angle of each firing is adjusted to be opposite the intersection position before the risk turns due to the very small speed increment that the thruster can provide.

If the method according to the scheme adjusts:

the two preceding n-2 turns of the risk turn (collision meeting turn) of the initial adjustment are preceded by 42 times of ignition, n is the turn number from the beginning of the track control strategy to the collision meeting turn, and n is a natural number.

Iterative calculation 1 st: the 1 st ignition time length is adjusted to 1500s, the subsequent ignition strategy is recalculated, the collision risk is recalculated, and the collision risk still exists with the risk target;

iterative calculation 2: the 1 st ignition time length is adjusted to 0s, the subsequent ignition strategy is recalculated, the collision risk is recalculated, and the collision risk still exists with the risk target;

iterative calculation 3 rd time: the ignition time length of the 2 nd time is adjusted to 1500s, the ignition time length of the 1 st time is 0s, the subsequent ignition strategy is recalculated, the collision risk is recalculated, and the collision risk still exists with the risk target;

iterative calculation 4: and (3) adjusting the time length of the ignition at the 2 nd time to be 0s, the time length of the ignition at the 1 st time to be 0s, recalculating a subsequent ignition strategy, recalculating collision risk, avoiding collision risk with a risk target and avoiding collision risk with other space targets, and executing a track control strategy.

As shown in fig. 4, UTCG represents time, the horizontal axis represents a time line, and the vertical axis represents a distance between a satellite and a risk target in km. The black line represents the intersection distance of the satellite and the risk target after the 1 st iteration of the scheme, the minimum distance of the closest moment is still smaller than 2km, the risk exists, the green line represents the intersection distance of the satellite and the risk target after the 2 nd iteration of the scheme, the minimum distance of the closest moment is still smaller than 2km, the risk exists, the blue line represents the intersection distance of the satellite and the risk target after the 3 rd iteration of the scheme, the minimum distance of the closest moment is still smaller than 2km, the risk exists, the purple line represents the intersection distance of the satellite and the risk target after the 4 th iteration of the scheme, the minimum distance of the closest moment is larger than 2km, the risk does not exist, and the yellow line represents the intersection distance of the satellite and the risk target under the original orbit control strategy. As can be seen from fig. 4, the present solution only reduces the ignition time by 6000 seconds, so that the collision risk can be avoided.

According to the scheme, the method is suitable for adjusting the track control strategy of one batch of high-frequency and low-thrust electric propulsion spacecraft lifting track to avoid collision risks, well fuses the avoiding strategy with the control strategy, realizes implementation of collision avoidance under the condition that normal track lifting task execution is not affected, and greatly saves cost.

The altitude avoidance method of ignition at a specified latitude argument is relatively limited and is not applicable in many cases. The constraints of different spacecrafts on energy sources are different, the constraints of the different spacecrafts on orbit parameters in the orbit raising process are different, for example, some electric thrusters carried by the spacecrafts can only work in an illumination area; some have strict requirements on the eccentricity in the track lifting process; some can only fire at a certain latitude argument or a certain position; if a plurality of collision risk targets appear, the situation height avoidance method such as inconsistent meeting positions is not applicable. For micro-bovine electric thrusters, the risk may not be circumvented even if the latitude angle of each firing is adjusted to be opposite the intersection position before the risk turns due to the very small speed increment that the thruster can provide. However, the invention does not adopt a method for avoiding the height, and simultaneously adjusts the ignition in advance in the initial track control process, so that the position of the intersection target does not need to be considered in the subsequent intersection process, and the invention is also applicable to the situation that a plurality of collision risks occur or the situation that the ignition position of the original strategy is opposite to the intersection position.

According to a third embodiment of the present invention, an electronic device is provided, as shown in fig. 5, and fig. 5 is a block diagram of an electronic device according to an exemplary embodiment.

An electronic device 500 according to this embodiment of the present application is described below with reference to fig. 5. The electronic device 500 shown in fig. 5 is merely an example, and should not be construed as limiting the functionality and scope of use of embodiments of the present application.

As shown in fig. 5, the electronic device 500 is embodied in the form of a general purpose computing device. The components of electronic device 500 may include, but are not limited to: at least one processing unit 510, at least one memory unit 520, a bus 530 connecting the different system components (including the memory unit 520 and the processing unit 510), a display unit 540, etc.

Wherein the storage unit stores program code that is executable by the processing unit 510 such that the processing unit 510 performs steps described in the present specification according to various exemplary embodiments of the present application. For example, the processing unit 510 may perform the steps shown in the second embodiment.

The memory unit 520 may include readable media in the form of volatile memory units, such as Random Access Memory (RAM) 5201 and/or cache memory unit 5202, and may further include Read Only Memory (ROM) 5203.

The storage unit 520 may also include a program/utility 5204 having a set (at least one) of program modules 5205, such program modules 5205 including, but not limited to: an operating system, one or more application programs, other program modules, and program data, each or some combination of which may include an implementation of a network environment.

Bus 530 may be one or more of several types of bus structures including a memory unit bus or memory unit controller, a peripheral bus, an accelerated graphics port, a processing unit, or a local bus using any of a variety of bus architectures.

The electronic device 500 may also communicate with one or more external devices 500' (e.g., keyboard, pointing device, bluetooth device, etc.), devices that enable a user to interact with the electronic device 500, and/or any devices (e.g., routers, modems, etc.) that the electronic device 500 can communicate with one or more other computing devices. Such communication may occur through an input/output (I/O) interface 550. Also, electronic device 500 may communicate with one or more networks such as a Local Area Network (LAN), a Wide Area Network (WAN), and/or a public network, such as the Internet, through network adapter 560. The network adapter 560 may communicate with other modules of the electronic device 500 via the bus 530. It should be appreciated that although not shown, other hardware and/or software modules may be used in connection with electronic device 500, including, but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, data backup storage systems, and the like.

From the above description of embodiments, those skilled in the art will readily appreciate that the example embodiments described herein may be implemented in software, or may be implemented in software in combination with the necessary hardware.

Thus, according to a fourth embodiment of the present invention, the present invention provides a computer readable medium. As shown in fig. 6, the technical solution according to the embodiment of the present invention may be embodied in the form of a software product, which may be stored in a non-volatile storage medium (may be a CD-ROM, a U-disk, a mobile hard disk, etc.) or on a network, and includes several instructions to cause a computing device (may be a personal computer, a server, or a network device, etc.) to perform the above-described method according to the embodiment of the present invention.

The software product may employ any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium can be, for example, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or a combination of any of the foregoing. More specific examples (a non-exhaustive list) of the readable storage medium would include the following: an electrical connection having one or more wires, a portable disk, a hard disk, random Access Memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

The computer readable storage medium may include a data signal propagated in baseband or as part of a carrier wave, with readable program code embodied therein. Such a propagated data signal may take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination of the foregoing. A readable storage medium may also be any readable medium that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. Program code embodied on a readable storage medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

Program code for carrying out operations of the present invention may be written in any combination of one or more programming languages, including an object oriented programming language such as Java, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code may execute entirely on the user's computing device, partly on the user's device, as a stand-alone software package, partly on the user's computing device, partly on a remote computing device, or entirely on the remote computing device or server. In the case of remote computing devices, the remote computing device may be connected to the user computing device through any kind of network, including a Local Area Network (LAN) or a Wide Area Network (WAN), or may be connected to an external computing device (e.g., connected via the Internet using an Internet service provider).

The computer-readable medium carries one or more programs which, when executed by one of the devices, cause the computer-readable medium to implement the functions of the second embodiment.

Those skilled in the art will appreciate that the modules may be distributed throughout several devices as described in the embodiments, and that corresponding variations may be implemented in one or more devices that are unique to the embodiments. The modules of the above embodiments may be combined into one module, or may be further split into a plurality of sub-modules.

From the above description of embodiments, those skilled in the art will readily appreciate that the example embodiments described herein may be implemented in software, or in combination with the necessary hardware. Thus, the technical solution according to the embodiments of the present invention may be embodied in the form of a software product, which may be stored in a non-volatile storage medium (may be a CD-ROM, a U-disk, a mobile hard disk, etc.) or on a network, and includes several instructions to cause a computing device (may be a personal computer, a server, a mobile terminal, or a network device, etc.) to perform the method according to the embodiments of the present invention.

The exemplary embodiments of the present invention have been particularly shown and described above. It is to be understood that this invention is not limited to the precise arrangements, instrumentalities and instrumentalities described herein; on the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A method for avoiding collision risk by combining a time avoidance method and a long-term rail lifting strategy, comprising the following steps:

s2: acquiring collision risk of satellites adopting an orbit control strategy; the acquiring collision risk of the satellite adopting the orbit control strategy comprises the following steps: acquiring collision risk of the satellite adopting the orbit control strategy according to the orbit control strategy of the satellite and ephemeris of other spacecrafts;

s5: steps S2 to S3 are repeatedly performed until there is no risk of collision.

2. The method for combining a time avoidance maneuver and a long term lift-off maneuver to avoid collision risk as recited in claim 1 wherein in step S1, the time of each ignition of the satellites is equal.

3. The method for combining a time avoidance method and a long term lift orbit maneuver to avoid collision risk according to claim 1 wherein in step S1 the orbit maneuver is a scheme of satellite ignition for a plurality of consecutive turns of the satellite within a predetermined time period, each turn being ignited at a rising intersection and/or a falling intersection.

4. The method of claim 2, wherein the direction of satellite ignition is consistent with the direction of satellite motion.

5. The method of claim 1, wherein in step S3, the duration of each reduced ignition is unchanged.

6. The method for combining a time avoidance maneuver and a long term lift rail maneuver to avoid collision risk as recited in claim 1 wherein, in step S3, prior to said forming the new rail maneuver: the ignition parameters and ephemeris after the ignition duration is reduced are recalculated.

7. A system for adjusting a tracking strategy, comprising:

the track control strategy making module is used for making a track control strategy; the orbit control strategy is a scheme that a satellite adopts satellite ignition in an electric pushing mode in a plurality of circles;

the collision risk prediction module is connected with the orbit control strategy making module and is used for calculating the collision risk of the satellite adopting the orbit control strategy according to the orbit control strategy; the acquiring collision risk of the satellite adopting the orbit control strategy comprises the following steps: acquiring collision risk of the satellite adopting the orbit control strategy according to the orbit control strategy of the satellite and ephemeris of other spacecrafts;

the collision intervention module is connected with the track control strategy making module and the collision risk prediction module and is used for judging the collision risk and adjusting the ignition duration, and if the collision risk does not exist, the track control strategy is executed; if there is a risk of collision: judging whether the duration of the ith ignition is 0 or not, if not, reducing the duration of the ith ignition in the track control strategy, otherwise, reducing the duration of the (i+1) th ignition in the track control strategy, wherein i=i+1, and the rest of the ignition strategies are kept unchanged to form a new track control strategy; i is a natural number greater than or equal to 1, i is 1 when judging for the first time, and repeatedly judging collision risk and adjusting the ignition duration until no collision risk exists;

8. An electronic device, comprising:

one or more processors;

a storage means for storing one or more programs;

the one or more programs, when executed by the one or more processors, cause the one or more processors to implement the combined time avoidance method and long-term lift-rail policy avoidance collision risk method of any of claims 1-6.

9. A computer readable medium having stored thereon a computer program, wherein the program when executed by a processor implements the method of combining a time avoidance method and a long-term lift-rail strategy avoidance collision risk as claimed in any one of claims 1 to 6.