A collision threat avoidance method based on moving target maneuver estimation

Abstract

The application provides a collision threat avoidance method based on moving target maneuver estimation, relates to the field of space safety, and particularly relates to the field of satellite collision warning, and the method comprises the following steps: establishing a relative motion model between a spacecraft and a moving target; determining a cascade observer model for estimating a moving target maneuver strategy according to the relative motion model; constructing a potential function according to the moving target maneuver strategy, task constraints of the spacecraft and maneuver capability of the spacecraft; and determining a collision threat avoidance strategy of the spacecraft based on the potential function and the relative motion model. The scheme can effectively avoid the collision threat caused by the moving target while taking into account the task execution of the spacecraft and the capability constraints of the spacecraft.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of space safety, in particular to the technical field of satellite and application industry, and specifically to a collision threat avoidance method based on moving target maneuver estimation. BACKGROUND

[0002] With the increasing challenges of spacecraft on-orbit operation safety, spacecraft need to have the ability to avoid space collision threats, and the control system, as the core of spacecraft to achieve space collision threat avoidance, has become a research hotspot at home and abroad. The potential function method is an effective method to design collision threat avoidance strategy, but the existing potential function design does not consider task constraints and spacecraft capability constraints, nor does it consider the maneuver strategy of moving targets. Due to the uncertainty and game nature of moving targets, spacecraft are also constrained by tasks and their own capabilities, so the existing potential function design method has limitations, and it is difficult to design an avoidance strategy that takes into account the task execution benefits while effectively avoiding the collision threat caused by moving targets. Therefore, there is an urgent need to provide a collision threat avoidance method based on moving target maneuver estimation. SUMMARY

[0003] The present application provides a collision threat avoidance method based on moving target maneuver estimation, which can effectively avoid the collision threat caused by moving targets while taking into account the spacecraft task execution and its own capability constraints.

[0004] In a first aspect, the present application provides a collision threat avoidance method based on moving target maneuver estimation, comprising:

[0005] establishing a relative motion model between the spacecraft and the moving target;

[0006] determining a cascaded observer model for estimating the moving target maneuver strategy according to the relative motion model;

[0007] constructing a potential function according to the moving target maneuver strategy, the task constraints of the spacecraft and its own maneuver capability;

[0008] determining the collision threat avoidance strategy of the spacecraft based on the potential function and the relative motion model.

[0009] In a second aspect, the present application further provides a collision threat avoidance device based on moving target maneuver estimation, comprising:

[0010] a relative motion module for establishing a relative motion model between the spacecraft and the moving target;

[0011] A construction module is configured to determine a cascade observer model for estimating the moving target maneuvering strategy based on the relative motion model; and to construct a potential function based on the moving target maneuvering strategy, the mission constraints of the spacecraft, and its own maneuvering capability;

[0012] A control module is used to determine a collision threat avoidance strategy for the spacecraft based on the potential function and the relative motion model.

[0013] In a third aspect, the present invention further provides a computing device comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, it implements any of the above-mentioned collision threat avoidance methods based on moving target maneuver estimation.

[0014] In a fourth aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, enables the computer to execute any of the above-mentioned methods for avoiding collision threats based on moving target maneuver estimation.

[0015] In a fifth aspect, an embodiment of the present invention further provides a computer program product, comprising computer instructions, which, when executed by a processor, implement the steps of the method described in any first aspect of this specification.

[0016] This invention provides a collision avoidance method based on moving target maneuver estimation. This method first establishes a relative motion model describing the spacecraft and the moving target. Secondly, a cascade observer model is designed to rapidly estimate the moving target's maneuver strategy, considering both unknown and partially measurable maneuver information. Then, a novel potential function is constructed for designing the threat avoidance strategy, taking into account the spacecraft's mission constraints, its own maneuverability, and the estimated target's maneuver strategy. Finally, based on the designed potential function and the relative motion model, a collision avoidance strategy is determined, and the effectiveness of the proposed collision avoidance strategy is verified through simulation. Thus, the proposed collision avoidance strategy's own maneuverability and all information can be measured by onboard sensors and acquired through information processing. Furthermore, the proposed collision avoidance strategy takes into account the spacecraft's mission constraints, thereby ensuring mission success to a certain extent. Furthermore, the moving target's maneuver strategy is further considered, resulting in a more rational and effective collision avoidance strategy. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings described below are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0018] Figure 1 is a flow chart of a collision threat avoidance method based on moving target maneuver estimation provided by an embodiment of the present application;

[0019] Figure 2 is a hardware architecture diagram of a computing device provided by an embodiment of the present application;

[0020] Figure 3 is a device structure diagram of a collision threat avoidance device based on moving target maneuver estimation provided by an embodiment of the present application;

[0021] Figure 4 is a structure diagram of a control system of a collision threat avoidance device based on moving target maneuver estimation provided by an embodiment of the present application. DETAILED DESCRIPTION

[0022] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will combine the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort fall within the protection scope of the present application.

[0023] Please refer to Figure 1 The embodiments of the present application provide a collision threat avoidance method based on moving target maneuver estimation, which comprises:

[0024] Step 100, establishing a relative motion model between a spacecraft and a moving target;

[0025] Step 102, determining a cascaded observer model for estimating a moving target maneuver strategy according to the relative motion model;

[0026] Step 104, constructing a potential function according to the moving target maneuver strategy, the task constraints of the spacecraft and the maneuver capability of the spacecraft itself;

[0027] Step 106, determining a collision threat avoidance strategy of the spacecraft based on the potential function and the relative motion model.

[0028] In the application, firstly, a relative motion model between a spacecraft and a moving target is established; secondly, a cascaded observer model is designed for fast estimation of the moving strategy of the moving target in the case that the moving information of the moving target is unknown and part of the information is measurable. Then, a new potential function for threat avoidance strategy design is constructed by considering the mission constraints of the spacecraft, the self-moving capability and the estimated moving strategy of the target. Finally, the collision threat avoidance strategy is determined according to the designed potential function and the relative motion model, and the effectiveness of the collision threat avoidance strategy is verified through simulation. Thus, the self-moving capability and the acquisition of all information involved in the application can be measured by on-board sensors and acquired through information processing; at the same time, the mission constraints are considered, so that the benefits of the mission can be ensured to a certain extent in the process of avoidance; and the moving strategy of the moving target is further considered, so that the collision threat avoidance strategy designed in the application is more reasonable and the avoidance effect is better.

[0029] The execution mode of each step is described below. Figure 1

[0030] Firstly, the spacecraft in step 100 includes a man-made satellite, a manned spacecraft (a space station and a manned spacecraft, etc.) and a space probe (a planet probe and a moon probe, etc.).

[0031] In step 100, a relative motion model between the spacecraft and the moving target is established, including:

[0032] The position vectors of the spacecraft and the moving target in the geocentric inertial coordinate system, the three-axis position control input and the three-axis relative motion position therebetween are acquired.

[0033] The relative motion model is determined according to the position vectors, the three-axis position control input and the three-axis relative motion position.

[0034] Specifically, the relative motion model is:

[0035]

[0036] Wherein, x so , y so and z so represent the three-axis relative motion position; r s = [x s , y s , z s ] T and r o = [x o , y o , z o ] T are the position vectors of the spacecraft and the moving target respectively; and ​Respectively, the distance from the spacecraft center of mass, the moving target center of mass to the center of the earth; u s = [u sx ,u sy ,u sz ] T And u o = [u ox ,u oy ,u oz ] T Respectively, the spacecraft three-axis position control input, the moving target three-axis position control input; f r The true anomaly of the reference mass point is f

[0037]

[0038]

[0039] Wherein, e r The eccentricity of the spacecraft orbit is a r The semi-major axis of the spacecraft orbit.

[0040] The three-axis relative motion position vector is defined as ρ1= [x so ,y so ,z so ] T The three-axis relative velocity vector is The spacecraft three-axis position control input u s = [u sx ,u sy ,u sz ] T And the moving target three-axis position control input (maneuvering acceleration) u o = [u ox ,u oy ,u oz ] T The relative motion model is rewritten as follows:

[0041]

[0042] Wherein, g = [g x ,g y ,g z ] T ,

[0043]

[0044] It should be noted that in the present application, (·) represents the first order time derivative relative to the geocentric inertial coordinate system; (··) represents the second order time derivative relative to the geocentric inertial coordinate system.

[0045] In step 102, the cascaded observer model is determined by the following formula:

[0046]

[0047] where s1 is the estimated value of the three-axis relative motion position vector p1; s2 is the estimated value of the three-axis relative velocity vector p2; e s1 = s1 - p1 = [e s1x , e s1y , e s1z ] T , and e s1 is the first estimation error; z1 is the estimated value of s2; z2 is the estimated value of the maneuvering acceleration u o of the moving target; e z1 = z1 - s2 = [e z1x , e z1y , e z1z ] T , and e z1 is the second estimation error; G s1 (e s1 ) = [G s1x , G s1y , G s1z ] T , and G s1l = |e s1l | 1 / 2 sign(e s1l ) ;

[0048] G s2 (e s1 ) = [G s2x , G s2y , G s2z ] T , and G s2l = sign(e s1l ) ; G z1 (e z1 ) = [G z1x , G z1y , G z1z ] T , and

[0049] G z1l = |e z1l | 1 / 2 sign(e z1l ) ; G z2 (e z1 ) = [G z2x , G z2y , G z2z ] T , and G z2l = sign(e z1l); wherein, l=x, y, z; g=[g x y z T ; β1, β2, β3, β4, δ1, δ2, δ3, δ4 are model parameters; A1, A2 are determined by the above formula.

[0050] For step 102, the estimated dynamic target maneuvering strategy includes:

[0051] Step S21, according to the relative motion model and the cascaded observer model, the estimation error dynamics equation is determined; the error dynamics equation is:

[0052]

[0053]

[0054] wherein, e z2 =z2-(-u o )=[e z2x ,e z2y ,e z2z ] T ; u o is the maneuvering acceleration of the dynamic target; e s2 , e z2 are estimation errors respectively; it is assumed that and wherein τ1 and τ2 are normal numbers;

[0055] Step S22, based on the estimation error dynamics equation and the model parameter constraint condition, the model parameters that minimize the estimation error are solved;

[0056] Specifically, after designing the cascaded observer model, the parameters β j (j=1, 2, 3, 4) are selected to satisfy the conditions β1>2, β2>0, and wherein

[0057]

[0058] The parameters δ j (j=1, 2, 3, 4) are selected to satisfy the conditions δ1>2, δ2>0, wherein

[0059]

[0060] Step S23, the model parameters are input into the cascaded observer model, and the dynamic target maneuvering strategy is estimated.

[0061] ​​​It should be noted that the maneuvering strategy of the moving target is the maneuvering acceleration u of the moving target o After the model parameters are determined, the unknown quantity in the error dynamics equation is only u o Therefore, the maneuvering strategy of the moving target can be directly calculated.

[0062] In step 104, according to the maneuvering strategy of the moving target, the task constraints of the spacecraft and the maneuvering capability of the spacecraft, a potential function is constructed as follows:

[0063]

[0064] Wherein, U a is a gravitational potential function; U r is a repulsive potential function of the moving target; ρ1 is a three-axis relative motion position vector between the spacecraft and the moving target; d s , d0 are empirical values; d(v sot ) is the minimum braking distance between the spacecraft and the moving target; p3, p4, p5 are all normal numbers; ρ2 is a three-axis relative velocity vector; a max =a s,max -a o represents the maximum relative acceleration between the spacecraft and the moving target, a s,max represents the maximum acceleration of the spacecraft; a o represents the active acceleration of the moving target, which is obtained by an estimation method. It is assumed that the maximum maneuvering capability of the spacecraft is greater than the maximum maneuvering capability of the target spacecraft. It should be noted that d s , d0 are determined by experience.

[0065] In the present application, considering the continuity of the spacecraft service and the self-capability constraints, and the maneuvering capability and game nature of the moving target, in order to quickly realize the avoidance of the collision threat, after the collision threat is warned, the spacecraft can maneuver in the direction of v sot ≤0, so that the spacecraft can not only maintain a safe distance from the moving target, but also ensure that the projection of the relative velocity vector between the spacecraft and the moving target on the relative position vector is ≤0. Therefore, by constructing the above potential function, the task target, collision threat avoidance and self-capability constraints are considered.v sot is the radial velocity of the moving target relative to the spacecraft.

[0066] In step 106, the collision threat avoidance strategy of the spacecraft is designed by using the potential function combined with the relative motion equation:

[0067]

[0068] In the formula, wherein

[0069]

[0070] Wherein, u s is the three-axis position control input of the spacecraft in the earth-centered inertial coordinate system;A1 and A2 are the first matrix and the second matrix respectively;ρ1 is the three-axis relative motion position vector between the spacecraft and the moving target;ρ2 is the three-axis relative velocity vector; are the first gradient and the second gradient of the potential function respectively;

[0071] At this time, since the data on the right side of the collision threat avoidance strategy formula can be obtained, the control strategy that meets the task and self-capability constraints and can avoid the collision threat of the spacecraft can be directly calculated.

[0072] In the present application, through the operation of the above four steps, the control strategy for avoiding the collision threat of the moving target can be obtained, and compared with the existing technology, the present application has the following beneficial effects: first, the cascade observer is designed, which can effectively and quickly estimate the maneuvering information of the moving target while meeting the efficient calculation. Second, the task constraint, self-manipulation capability constraint and moving target maneuvering strategy are fused into the potential function design, so that the collision threat avoidance strategy designed by the constructed potential function can avoid the collision threat of the moving target while guaranteeing the execution of the business, and the designed avoidance strategy is within the range of achievable capability.

[0073] As shown in Figure 2 , Figure 3 , the embodiment of the present application provides a collision threat avoidance device based on moving target maneuvering estimation. The device embodiment can be realized by software, or realized by hardware or a combination of software and hardware. From the hardware layer, as shown in Figure 2 , it is a hardware architecture diagram of a computing device where the collision threat avoidance device based on moving target maneuvering estimation provided by the embodiment of the present application is located. In addition to the processor, memory, network interface and non-volatile memory shown in Figure 2 , the computing device where the device in the embodiment is usually also can include other hardware, such as a forwarding chip responsible for processing packets and the like. Taking the software implementation as an example, as shown in Figure 3 , as a logically meaningful device, it is formed by the CPU of the computing device where it is located to read the corresponding computer program in the non-volatile memory into the memory for running. The collision threat avoidance device based on moving target maneuvering estimation provided by the embodiment of the present application comprises:

[0074] The relative motion module 300 is used to establish a relative motion model between the spacecraft and the moving target;

[0075] The constructing module 302 is configured to determine a cascaded observer model for estimating a maneuvering strategy of the dynamic target according to a relative motion model, and construct a potential function according to the maneuvering strategy of the dynamic target, a mission constraint of the spacecraft, and a maneuvering capability of the spacecraft.

[0076] The controlling module 304 is configured to determine a collision threat avoidance strategy of the spacecraft based on the potential function and the relative motion model.

[0077] In some specific embodiments, the relative motion module 300 can be configured to perform the step 100 described above, the constructing module 302 can be configured to perform the steps 102 and 104 described above, and the controlling module 304 can be configured to perform the step 106 described above.

[0078] In some specific embodiments, the relative motion module 300 is further configured to perform the following operations:

[0079] obtain a position vector of the spacecraft and the dynamic target in a geocentric inertial coordinate system, a three-axis position control input, and a three-axis relative motion position between the spacecraft and the dynamic target;

[0080] determine the relative motion model according to the position vector, the three-axis position control input, and the three-axis relative motion position.

[0081] In some specific embodiments, the constructing module 302 is further configured to perform the following operations:

[0082] The cascaded observer model is determined by the following formula:

[0083]

[0084] wherein s1 is an estimated value of the three-axis relative motion position vector p1; s2 is an estimated value of a three-axis relative velocity vector p2; e s1 = s1- p1= [e s1x ,e s1y ,e s1z ] T , and e s1 is a first estimation error; z1 is an estimated value of s2; z2 is an estimated value of a maneuvering acceleration u o of the dynamic target; e z1 = z1- s2= [e z1x ,e z1y ,e z1z ] T , and e z1 is a second estimation error; G s1 (e s1 ) = [G s1x , G s1y , G s1z ] T , and G s1l = |es1l | 1 / 2 sign(e s1l );

[0085] Γ s2 (e s1 )=[Γ s2x ,Γ s2y ,Γ s2z ] T , and Γ s2l =sign(e s1l );Γ z1 (e z1 )=[Γ z1x ,Γ z1y ,Γ z1z ] T ,and

[0086] Γ z1l =|e z1l | 1 / 2 sign(e z1l );Γ z2 (e z1 )=[Γ z2x ,Γ z2y ,Γ z2z ] T , and Γ z2l =sign(e z1l ); where l = x, y, z; β1, β2, β3, β4, δ1, δ2, δ3, δ4 are all model parameters; A1 and A2 are the first matrix and the second matrix respectively.

[0087] In some specific implementations, the construction module 302 is further configured to perform the following operations:

[0088] Step S21: Determine the estimated error dynamic equation based on the relative motion model and the cascade observer model; the error dynamic equation is:

[0089]

[0090] in, e z2 =z2-(-u o )=[e z2x ,e z2y ,e z2z ] T ;u o is the maneuvering acceleration of the moving target; e s2 、e z2 are the estimation errors; assuming and Where τ1 and τ2 are positive constants;

[0091] Step S22, based on the estimation error dynamics equation and the model parameter constraint condition, solving the model parameter that minimizes the estimation error;

[0092] Specifically, after designing the cascaded observer model, the parameters β j (j = 1, 2, 3, 4) are selected to satisfy the conditions β1> 2, β2> 0, and wherein

[0093]

[0094] The parameters δ j (j = 1, 2, 3, 4) are selected to satisfy the conditions δ1> 2, δ2> 0, wherein

[0095]

[0096] Step S23, inputting the model parameters into the cascaded observer model to estimate the maneuvering strategy u o of the moving target.

[0097] In some specific embodiments, the construction module 302 is further configured to perform the following operations:

[0098] The constructed potential function is:

[0099]

[0100] wherein, U a is a gravitational potential energy function; U r is a repulsive potential energy function of the moving target; ρ1is a three-axis relative motion position vector between the spacecraft and the moving target; d s , d0are both empirical values; d(v sot ) is the minimum braking distance between the spacecraft and the moving target; p3, p4, p5are all normal numbers; ρ2is a three-axis relative velocity vector.

[0101] In some specific embodiments, the control module 304 is further configured to perform the following operations:

[0102] The collision threat avoidance strategy is determined by the following formula:

[0103]

[0104] wherein, u s is a three-axis position control input of the spacecraft in the geocentric inertial coordinate system; A1, A2are respectively a first matrix and a second matrix; ρ1is a three-axis relative motion position vector between the spacecraft and the moving target; ρ2is a three-axis relative velocity vector; are the first gradient and the second gradient of the potential function respectively.

[0105] like Figure 4 In the control system shown, the ranging and velocity information of the spacecraft and the moving target, including the position vector, velocity vector, acceleration vector, etc., can be obtained by the measurement sensor; the measurement sensor sends the ranging and velocity information to the cascade observer constructed by the construction module to obtain relative position information, relative velocity information and the moving target maneuvering strategy; then, based on the obtained information combined with the mission objectives and its own maneuvering capabilities, an avoidance potential function (i.e., potential function) is constructed, and then the control module (i.e., collision threat avoidance controller) determines the collision threat avoidance strategy of the spacecraft based on its own maneuvering capabilities, the moving target maneuvering strategy and the relative position information and relative velocity information of the two, so as to control the operation of the spacecraft by transmitting the collision threat avoidance strategy to the actuator.

[0106] It should be understood that the structure illustrated in the embodiments of the present invention does not constitute a specific limitation on a collision threat avoidance device based on moving target maneuver estimation. In other embodiments of the present invention, a collision threat avoidance device based on moving target maneuver estimation may include more or fewer components than illustrated, or may combine or separate certain components, or employ different component arrangements. The illustrated components may be implemented in hardware, software, or a combination of both.

[0107] The information interaction, execution process, etc. between the modules in the above-mentioned device are based on the same concept as the embodiment of the method of the present invention. For specific contents, please refer to the description in the embodiment of the method of the present invention and will not be repeated here.

[0108] An embodiment of the present invention further provides a computing device comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, a collision threat avoidance method based on moving target maneuver estimation in any embodiment of the present invention is implemented.

[0109] An embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the processor executes a collision threat avoidance method based on moving target maneuver estimation in any embodiment of the present invention.

[0110] An embodiment of the present application also provides a computer program product, which includes a computer program. A processor of a computer device reads the computer program from a computer-readable storage medium, and the processor executes the computer program, so that the computer device executes a collision threat avoidance method based on moving target maneuver estimation as described in any of the above embodiments.

[0111] Specifically, a system or apparatus equipped with a storage medium on which a software program code for implementing the functions of any of the above-described embodiments is stored, and a computer (or CPU or MPU) of the system or apparatus can be provided, and the computer (or CPU or MPU) can be caused to read out and execute the program code stored in the storage medium.

[0112] In this case, the program code read out from the storage medium can implement the functions of any of the above-described embodiments, and the program code itself and the storage medium which stores the program code constitute the present application.

[0113] Embodiments of the storage medium for supplying the program code include a floppy disk, a hard disk, an optical disk such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW, a magnetic tape, a nonvolatile memory card, and a ROM. Alternatively, the program code can be downloaded from a server computer via a communication network.

[0114] Further, it should be understood by those skilled in the art that not only the program code read out by the computer, but also the operating system or the like operating on the computer based on the instructions of the program code can perform part or all of the actual operations to realize the functions of any of the above-described embodiments.

[0115] Further, it should be understood by those skilled in the art that the program code read out from the storage medium can be written into a memory provided in an expansion board inserted into the computer or a memory provided in an expansion module connected to the computer, and then part or all of the actual operations can be performed by a CPU or the like mounted on the expansion board or the expansion module based on the instructions of the program code to realize the functions of any of the above-described embodiments.

[0116] It should be noted that the terms such as first and second, which are used herein merely to distinguish one entity or operation from another, do not necessarily require or imply that these entities or operations are in any such actual relationship or order. Moreover, the terms "comprising", "including" or any other variant thereof are intended to cover a non-exclusive inclusion, so that a process, method, article or apparatus that includes a list of elements does not include only those elements recited, but can also include other elements not expressly listed or inherent to such process, method, article or apparatus. Without further limitation, an element preceded by "comprising" does not, without more limitations, preclude the existence of additional identical elements in the process, method, article or apparatus that includes the recited element.

[0117] Those skilled in the art can understand that all or part of the steps of the above-mentioned method embodiments can be completed by program instruction related hardware, and the foregoing program can be stored in a computer readable storage medium. When the program is executed, the steps of the above-mentioned method embodiments are executed; and the foregoing storage medium includes various storage media that can store program codes, such as ROM, RAM, magnetic disk or optical disk.

[0118] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A collision threat avoidance method based on moving target maneuver estimation, characterized in that, Comprising: establishing a relative motion model between a spacecraft and a moving target; determining a cascaded observer model for estimating a moving strategy of the moving target according to the relative motion model; constructing a potential function according to the moving strategy of the moving target, mission constraints and self maneuvering capability of the spacecraft; the potential function is: wherein U a is a gravitational potential function; U r is a repulsive potential function of the moving target; based on the potential function and the relative motion model, determining a collision threat avoidance strategy of the spacecraft; the collision threat avoidance strategy is determined by the following formula: 1is a three-axis relative motion position vector between the spacecraft and the moving target; d s , d 0are all empirical values; d ( v sot ) is a minimum braking distance between the spacecraft and the moving target; p 3、 p 4、 p 5are all normal numbers; , the establishing of the relative motion model between the spacecraft and the moving target comprises: 2is a three-axis relative velocity vector; obtaining position vectors of the spacecraft and the moving target in a geocentric inertial coordinate system, three-axis position control inputs and three-axis relative motion positions therebetween; wherein, u s a three-axis position control input for the spacecraft in a geocentric inertial coordinate system; A 1、 A 2 are a first matrix and a second matrix, respectively; determining a relative motion model according to the position vectors, the three-axis position control inputs and the three-axis relative motion positions. 1 is a three-axis relative motion position vector between the spacecraft and the moving target; the cascaded observer model is determined by the following formula: 2 is a three-axis relative velocity vector; 、 are a first gradient and a second gradient of the potential function, respectively.

2. The method of claim 1, wherein, based on the estimation error dynamics equation and a model parameter constraint condition, solving a model parameter that minimizes the estimation error; the model parameter is input into the cascaded observer model to estimate the moving strategy of the moving target. the estimation error dynamics equation is:

3. The method of claim 1, wherein, 6. The method of claim 4, wherein, wherein s 1 is a three-axis relative motion position vector between the spacecraft and the maneuvering target the model parameter constraint condition is: 1 is an estimate of 1 ; s 2 is a three-axis relative velocity vector including: 2 is an estimate of 2 ; , and e s1 is a first estimation error; z 1 is an estimate of 1 ; s 2 is an estimate of 2 ; z 2 is an estimate of the maneuvering acceleration of the maneuvering target; , and e z1 is a second estimation error; , and ; , and ; , and ; , and ; wherein, l = x , y , z ; denotes the first order time derivative with respect to the relative geocentric inertial coordinate system; β 1, β 2, β 3, β 4, a relative motion module, configured to establish a relative motion model between a spacecraft and a moving target; 1, a construction module, configured to determine a cascaded observer model for estimating a moving strategy of the moving target according to the relative motion model; and to construct a potential function according to the moving strategy of the moving target, mission constraints and self maneuvering capability of the spacecraft; 2, a control module, configured to determine a collision threat avoidance strategy of the spacecraft based on the potential function and the relative motion model. 3, the construction module is further configured to perform the following operations: 4 are model parameters; A 1, A 2 are a first and a second matrix, respectively.

4. The method of claim 1, wherein, determining an estimation error dynamics equation according to the relative motion model and the cascaded observer model; based on the estimation error dynamics equation and a model parameter constraint condition, solving a model parameter that minimizes the estimation error; the model parameter is input into the cascaded observer model to estimate the moving strategy of the moving target.

9. A computing device comprising a memory and a processor, the memory having stored therein a computer program, the processor implementing the method of any one of claims 1-6 when executing the computer program.

5. The method of claim 4, wherein, 10. A computer readable storage medium having stored therein a computer program, the computer program, when executed in a computer, causing the computer to perform the method of any one of claims 1-6. wherein , ; ; u o is the maneuvering acceleration of the moving object. ​ ​ wherein β 1, β 2, β 3, β 4, ​ 1, ​ 2, ​ 3, ​ 4 are model parameters; , , , ; , , , .

7. A collision threat avoidance device based on moving target maneuver estimation, for implementing the method of any one of claims 1 to 6, characterized in that, ​ ​ ​ ​ 8. The apparatus of claim 7, wherein, ​ ​ ​ ​ ​ ​

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