Hybrid target based quasi-phase synchronization orbit design method, medium and device

Abstract

The application provides a quasi-phase synchronous orbit design method based on a mixed target point, a medium and equipment, and belongs to the technical field of orbit design and orbit determination prediction combination. The application bypasses ring surface information inversion under sparse data through definition of the quasi-phase synchronous orbit, constructs an allowable ephemeris data set to represent the ring surface in a limited time; the mixed target point construction is realized based on the allowable ephemeris data set, and the real target point and the virtual target point satisfy the quasi-phase synchronous orbit constraint of quasi-phase synchronization and ring surface renormalization respectively; the quasi-phase synchronous orbit design based on the mixed target point is carried out through the multi-point shooting method under the expression of the optimization problem, the quasi-phase synchronous orbit is successfully constructed, and long-term monitoring of the areocorrelation non-cooperative target is realized. Based on the geometric constraint of the areocorrelation non-cooperative target orbit maintenance, the multi-point shooting is used for orbit design, which is simple and convenient, and can provide stable observation guidance and efficient precise orbit determination priori initial value in actual tasks.

Description

Technical Field

[0001] This invention belongs to the field of orbit design and orbit prediction composite technology, specifically involving a quasi-phase synchronous orbit design method, medium and equipment based on hybrid target points. It is applicable to telescope guidance and precise orbit determination a priori values ​​for non-cooperative targets at translational points in the Earth-Moon space situational awareness, enabling long-term monitoring and cataloging maintenance. Background Technology

[0002] As human exploration of the Earth-Moon space continues to deepen, the Earth-Moon libration point region, as a crucial hub for Earth-Moon transfer and space perception, is becoming increasingly strategically valuable. However, the orbital motion of spacecraft in this region is dominated by multi-body gravity, exhibiting strong nonlinearity and high sensitivity to initial conditions. Furthermore, constraints such as the long distance of ground-based optical observations, interference from lunar background light, and lunar phase changes result in sparse and unevenly distributed observational data, posing significant challenges to the accurate orbit determination and long-term monitoring of non-cooperative spacecraft.

[0003] The existing technology has the following main problems:

[0004] First, the dynamic prediction error diverges sharply. The strong instability in the translational point region causes the orbit prediction error to amplify dramatically in the short term. The predicted trajectory often deviates significantly from the actual trajectory within a few days, making it impossible to capture the target in subsequent observation windows and forcing the monitoring process to be interrupted.

[0005] Second, harsh observation conditions lead to sparse data and uncertainty regarding maneuvers. The target has a low apparent magnitude, strong background noise from moonlight along the Earth-Moon line, and lunar phase changes make long-term observations infeasible, resulting in short and scattered observation arcs. Sparse data makes it difficult to support high-precision orbit determination, and the target may maneuver along unknown trajectories during observation intervals, further exacerbating the difficulty of orbit determination convergence and increasing positioning errors.

[0006] Third, traditional tracking and monitoring models lack global constraints. Existing tracking strategies rely excessively on the latest local trajectory determination results, failing to fully utilize the global dynamic structure information contained in the target's historical motion. They also lack effective error correction and backup mechanisms when the target maneuvers or the model is inaccurate, which can easily lead to target loss and cataloging interruptions.

[0007] Therefore, there is an urgent need to develop a method for orbit construction and monitoring that can adapt to the strong nonlinearity and sparse observation conditions in the Earth-Moon libration region and does not rely on continuous high-precision orbit determination. Summary of the Invention

[0008] This invention addresses the shortcomings of existing technologies by providing a quasi-phase-synchronous orbit design method, medium, and equipment based on hybrid target points. It solves the problems of rapid divergence of prediction errors and difficulty in long-term stable monitoring of non-cooperative spacecraft under sparse observation and strongly nonlinear environments, which are challenges of traditional orbit tracking methods. This invention constructs global geometric constraints by mining invariant torus information from historical ephemeris data and integrating the latest predicted local motion trends to build an equivalent orbit that can maintain phase synchronization with the actual orbit over a relatively long period. This provides reliable support for telescope observation guidance and orbit improvement.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a quasi-phase synchronization orbit design method based on hybrid target points, comprising: Step 1: Obtain the historical ephemeris data of the target spacecraft, which includes orbit extrapolation results and quasi-phase synchronous orbit; Step 2: Construct an initial finite-time torus neighborhood dataset based on historical ephemeris data. By filtering out stable and unstable manifold components, gradually accumulate and classify the dataset to obtain the historical ordinal torus ephemeris set and the latest ordinal torus ephemeris set. The historical ordinal torus ephemeris set contains all filtered ephemeris data, and the latest ordinal torus ephemeris set contains the latest orbit extrapolation results after filtering. Step 3: Calculate the dominant phase parameters based on the historical permissible toroidal ephemeris to characterize the geometric features of the target toroidal surface; Step 4: Based on the dominant phase parameter, extract real target points from the latest ordinal ephemeris set, construct virtual target points based on the historical ordinal ephemeris set using the phase averaging method, and combine the real target points and virtual target points to obtain a hybrid target point set. Step 5: Under the multi-point firing framework, each target in the mixed target set is taken as the firing node, the node state is taken as the optimization variable, the trajectory continuity between adjacent nodes is taken as the constraint, and the objective is to minimize the relative state correction of the real target. Step 6: Perform multi-point target shooting and select the solution that minimizes the correction amount of the actual target state as the quasi-phase synchronous orbit of the target spacecraft.

[0010] Optionally, in step 1, the historical ephemeris data includes ephemeris data for one complete orbital period of the target spacecraft, which is used to construct an initial finite-time toroidal neighborhood dataset.

[0011] Optionally, in step 2, the process of obtaining the historical permissible toroidal ephemeris and the latest permissible toroidal ephemeris is as follows: Based on the dynamic characteristics of the torus, whisker-like structure data corresponding to stable and unstable manifolds are identified and removed. The retained data are accumulated into the historical permissible torus ephemeris, and the data obtained only by the latest orbit extrapolation results are used as the latest permissible torus ephemeris.

[0012] Optionally, in step 3, the dominant phase parameter is obtained by analyzing the angular evolution of orbital states in the historical permissible toroidal ephemeris and extracting the phase corresponding to the dominant frequency that reflects the changes in the toroidal geometry.

[0013] Optionally, in step 4, the method for extracting the real target points is as follows: The latest permissive toroidal ephemeris is sampled at preset fixed time intervals, and the time of the last sampled point is kept consistent with the most recent time in the latest permissive toroidal ephemeris.

[0014] Optionally, in step 4, the virtual target is constructed as follows: Based on the dominant phase parameter, the orbital states in the historical permissible toroidal ephemeris set are divided into different phase sequences according to the preset phase sequence; for each phase, all orbital states that meet the conditions are counted, and the average orbital state is calculated as the state vector of the virtual target point corresponding to that phase; the average extrapolation time of the orbital states between adjacent phases is counted to determine the time distribution of the virtual target point.

[0015] Optionally, in step 5, during the construction of the optimization problem, a threshold for the actual target correction amount is also set.

[0016] Optionally, in step 6, during the solution process, only the target convergence results with correction amounts less than the actual target correction amount threshold are taken as candidate solutions. From the candidate solutions, the solution with the smallest actual target state correction amount is selected as the quasi-phase synchronization orbit. The selected solution is an orbit that satisfies the toroidal neighborhood constraint and the quasi-phase synchronization constraint. The toroidal neighborhood constraint is that the orbital state is located within the target toroidal neighborhood. For the toroidal information set T and the preset distance ε, the orbital state X satisfies d(X,T) ≤ ε, where d represents the distance. The quasi-phase synchronization constraint is that the difference between the parameterized angles of the orbit and the target orbit is less than a preset angle threshold. The target torus and its neighborhood are jointly characterized by the historical permissible torus ephemeris and the dominant phase parameter.

[0017] In a second aspect, the present invention provides a computer-readable storage medium storing a computer program that causes a computer to execute the quasi-phase synchronization orbit design method based on hybrid targets as described in the first aspect.

[0018] Thirdly, the present invention provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, it implements the quasi-phase synchronization orbit design method based on hybrid targets as described in the first aspect.

[0019] The beneficial effects of this invention are: (1) It uses historical ephemeris data of spacecraft to extract the dynamic topology of the torus and provides global geometric constraints by constructing virtual target points, which overcomes the shortcomings of traditional methods that rely only on local orbit determination results and lack long-term robustness; (2) It integrates the latest orbit extrapolation results to construct real target points, maintains the local fitting ability of the target's current motion trend, and the virtual target points and real target points work together to make the constructed quasi-phase synchronous orbit reflect the overall motion law and track the recent real state; (3) Under the conditions of sparse observation and unknown orbits maintaining maneuverability, the method does not require continuous high-precision orbit determination, which can effectively suppress prediction divergence and provide reliable telescope guidance and orbit improvement initial values ​​for subsequent observation windows; (4) Through multi-point target optimization framework and correction threshold control, the obtained orbit maintains phase synchronization with the real orbit to the greatest extent while satisfying the torus geometric constraints, which significantly improves the continuity and stability of long-term tracking of non-cooperative spacecraft. Attached Figure Description

[0020] Figure 1 This is a flowchart illustrating the overall process of the method of the present invention. Figure 2 A schematic diagram showing the selection of quasi-periodic torus and hybrid target points; Figure 3 To observe the observation residuals of non-cooperative targets in the Halo orbit using quasi-phase synchronous orbits and orbit extrapolation results; Figure 4 The observation residuals of non-cooperative targets in the Lyapunov orbit were obtained using quasi-phase synchronous orbits and orbit extrapolation results.

[0021] Figure 5 The diagram shows the orbit extrapolation results and the quasi-phase synchronous orbit, demonstrating the qualitative toroidal neighborhood preservation capability. Figure 6 This is a schematic diagram illustrating the toroidal neighborhood retention time, demonstrating the quantitative toroidal neighborhood retention capability; Detailed Implementation The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0022] In one embodiment, the quasi-phase synchronization orbit design method based on hybrid target points proposed in this invention includes the following steps: Step 1: Obtain historical ephemeris data for the target spacecraft. This data includes orbit extrapolation results and a quasi-phase-synchronous orbit. The historical ephemeris data must contain ephemeris data for at least one complete orbital period of the target spacecraft, used to construct an initial finite-time torus neighborhood dataset.

[0023] Step 2: Construct an initial finite-time torus neighborhood dataset based on historical ephemeris data. By filtering out stable and unstable manifold components, gradually accumulate and classify the dataset to obtain the historical ordinal torus ephemeris set and the latest ordinal torus ephemeris set. The historical ordinal torus ephemeris set contains all filtered ephemeris data, and the latest ordinal torus ephemeris set contains the latest orbit extrapolation results after filtering.

[0024] The iterative screening process includes: identifying and removing whisker-like structure data corresponding to stable and unstable manifolds based on toroidal dynamics; accumulating the retained data into a historical permissible toroidal ephemeris; and using the data obtained solely from the latest orbit extrapolation results as the latest permissible toroidal ephemeris.

[0025] Step 3: Calculate the dominant phase parameters based on the historical permissible toroidal ephemeris to characterize the geometric features of the target toroid. The dominant phase parameters are obtained by analyzing the angular evolution of orbital states in the historical permissible toroidal ephemeris and extracting the phase corresponding to the dominant frequency reflecting changes in the toroidal geometry.

[0026] Step 4: Based on the dominant phase parameters, extract real target points from the latest ordinal ephemeris set, and construct virtual target points based on the historical ordinal ephemeris set using the phase averaging method. Combine the real target points and virtual target points to obtain a hybrid target point set.

[0027] The method for extracting the true target point is as follows: the latest permissive toroidal ephemeris is sampled at a preset fixed time interval, and the time of the last sampled point is kept consistent with the most recent time in the latest permissive toroidal ephemeris to maintain a high degree of confidence in phase synchronization.

[0028] The virtual target is constructed as follows: based on the dominant phase parameter, the orbital states in the historical allowable toroidal ephemeris set are divided into different phase sequences according to the preset phase sequence; for each phase, all orbital states that meet the conditions are counted, and the average orbital state is calculated as the state vector of the virtual target corresponding to that phase, thereby realizing toroidal geometric renormalization; the average extrapolation time of the orbital states between adjacent phases is counted to determine the time distribution of the virtual target, thereby realizing extrapolation time renormalization.

[0029] Step 5: Within the multi-point firing framework, each target in the mixed target set is used as a firing node, the node state is used as the optimization variable, the trajectory continuity between adjacent nodes is used as the constraint, and the objective is to minimize the relative correction amount of the state of the real target. The optimization problem also sets a threshold for the correction amount of the real target; during the solution process, only firing convergence results with correction amounts less than the threshold are considered as candidate solutions.

[0030] Step 6: Perform multi-point target shooting and select the solution that minimizes the correction amount of the actual target state as the quasi-phase synchronous orbit of the target spacecraft.

[0031] The selected solution must satisfy the definition of a quasi-phase synchronous orbit, that is, an orbit that satisfies the following constraints: (1) Constraint 1: Toroidal neighborhood constraint, that is, the orbital state is located within the neighborhood of the target toroidal surface. For the toroidal information set T and the preset distance ε, the orbital state X satisfies d(X,T) ≤ ε; (2) Constraint 2: Quasi-phase synchronization constraint, that is, the difference between the parameterized angles of the orbit and the target orbit is less than the preset angle threshold.

[0032] The target torus and its neighborhood are characterized by a combination of historical permissive torus ephemeris and dominant phase parameters.

[0033] This embodiment focuses on a non-cooperative spacecraft in Halo and Planar Lyapunov orbits near the collinear translation points L1 and L2 of the Earth-Moon system, whose prior ephemeris data has accumulated to approximately one month's worth of historical data. The goal is to construct a quasi-phase-synchronous orbit capable of providing telescope guidance and initial orbit determination values ​​in the next observation window. (Refer to...) Figure 1 The overall process is shown below, and the specific implementation steps are as follows: (1) Obtain historical ephemeris data and calculate the dominant phase parameters of the historical ephemeris data.

[0034] (2) Based on the dominant phase parameters, mixed target data is extracted from historical ephemeris data: the latest segment of permissible toroidal ephemeris data is selected for the real target, and samples are taken at fixed time intervals (e.g., 0.2 days), ensuring that the time of the last sampled point is consistent with the latest ephemeris time to guarantee the confidence of phase synchronization; the state vector of the virtual target is obtained by averaging the historical orbital states of the same phase interval, and its epoch is determined by the average extrapolated time between adjacent phase intervals, thereby simultaneously achieving toroidal geometric renormalization and extrapolated time renormalization, such as Figure 2 As shown.

[0035] (3) Using each node of the mixed target point as the firing node, the node state as the optimization variable, the circular constraint three-body problem dynamic equation between adjacent nodes as the constraint condition, and minimizing the state correction of all real target points as the optimization objective, the multi-point firing problem is solved through Newton iteration. The solution that satisfies the correction threshold and minimizes the average correction of the real target points is taken as the initial quasi-phase synchronization orbit. The first observation window is guided by this orbit, and its observation residual is as follows: Figure 3 and Figure 4 As shown, this value is used as the initial a priori value for precise orbit determination. Combined with the angle measurement data obtained through this window, orbit improvement is performed to obtain a new orbit determination extrapolation result. The toroidal maintenance time of this extrapolation result is compared with that of the quasi-phase synchronous orbit, for example... Figure 5 and Figure 6 As shown.

[0036] (4) Based on the data accumulation from the first orbit determination, the extrapolation results from the first orbit determination are incorporated into the historical data and manifold filtering is performed: data points that are distributed in a whisker-like pattern along the directions of stable and unstable manifolds are identified and removed. The retained data are accumulated and updated into the historical permissible toroidal ephemeris, and the filtered data from this orbit determination extrapolation is used as the new latest permissible toroidal ephemeris. Based on the updated dataset, real and virtual target points are re-extracted in the same way as in step (2).

[0037] (5) Based on the mixed target set obtained in step (4), multi-point target optimization is performed again to design a quasi-phase synchronization orbit for the next observation window. This orbit is also used for telescope guidance and as a priori initial value for the next orbit determination.

[0038] (6) The process of iteratively executing steps (4) to (5) continuously accumulates historical ephemeris data and updates the toroidal neighborhood representation as the observation window advances, thereby continuously constructing new quasi-phase-synchronous orbits. Through the above iterative process, long-term continuous tracking and cataloging of the test target from January to March 2026 was achieved. During this period, each round of quasi-phase-synchronous orbits can effectively suppress forecast divergence under sparse observation conditions and stably provide observation guidance and initial orbit determination values.

[0039] In another embodiment, the present invention provides a computer-readable storage medium storing a computer program that causes a computer to execute the hybrid target-based quasi-phase synchronization orbit design method of the foregoing embodiments.

[0040] In another embodiment, the present invention proposes an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the quasi-phase synchronization orbit design method based on hybrid targets as described in the foregoing embodiments.

[0041] In the embodiments disclosed in this application, a computer storage medium may be a tangible medium that may contain or store programs for use by or in conjunction with an instruction execution system, apparatus, or device. The computer storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of computer storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CDROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0042] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed in this application can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0043] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A quasi-phase synchronization orbit design method based on hybrid target points, characterized in that, include: Step 1: Obtain the historical ephemeris data of the target spacecraft, which includes orbit extrapolation results and quasi-phase synchronous orbit; Step 2: Construct an initial finite-time torus neighborhood dataset based on historical ephemeris data. By filtering out stable and unstable manifold components, gradually accumulate and classify the dataset to obtain the historical ordinal torus ephemeris set and the latest ordinal torus ephemeris set. The historical ordinal torus ephemeris set contains all filtered ephemeris data, and the latest ordinal torus ephemeris set contains the latest orbit extrapolation results after filtering. Step 3: Calculate the dominant phase parameters based on the historical permissible toroidal ephemeris to characterize the geometric features of the target toroidal surface; Step 4: Based on the dominant phase parameter, extract real target points from the latest ordinal ephemeris set, construct virtual target points based on the historical ordinal ephemeris set using the phase averaging method, and combine the real target points and virtual target points to obtain a hybrid target point set. Step 5: Under the multi-point firing framework, each target in the mixed target set is taken as the firing node, the node state is taken as the optimization variable, the trajectory continuity between adjacent nodes is taken as the constraint, and the objective is to minimize the relative state correction of the real target. Step 6: Perform multi-point target shooting and select the solution that minimizes the correction amount of the actual target state as the quasi-phase synchronous orbit of the target spacecraft.

2. The quasi-phase synchronization orbit design method based on hybrid target points as described in claim 1, characterized in that: In step 1, the historical ephemeris data contains ephemeris data for one complete orbital period of the target spacecraft, which is used to construct an initial finite-time toroidal neighborhood dataset.

3. The quasi-phase synchronization orbit design method based on hybrid target points as described in claim 1, characterized in that: In step 2, the process of obtaining the historical permissible toroidal ephemeris and the latest permissible toroidal ephemeris is as follows: Based on the dynamic characteristics of the torus, whisker-like structure data corresponding to stable and unstable manifolds are identified and removed. The retained data are accumulated into the historical permissible torus ephemeris, and the data obtained only by the latest orbit extrapolation results are used as the latest permissible torus ephemeris.

4. The quasi-phase synchronization orbit design method based on hybrid target points as described in claim 1, characterized in that: In step 3, the dominant phase parameter is obtained by analyzing the angular evolution of the orbital states in the historical permissible toroidal ephemeris and extracting the phase corresponding to the dominant frequency that reflects the changes in the toroidal geometry.

5. The quasi-phase synchronization orbit design method based on hybrid target points as described in claim 1, characterized in that: In step 4, the method for extracting the real target points is as follows: The latest permissive toroidal ephemeris is sampled at preset fixed time intervals, and the time of the last sampled point is kept consistent with the most recent time in the latest permissive toroidal ephemeris.

6. The quasi-phase synchronization orbit design method based on hybrid target points as described in claim 1, characterized in that: In step 4, the virtual target is constructed as follows: Based on the dominant phase parameter, the orbital states in the historical permissible toroidal ephemeris set are divided into different phase sequences according to the preset phase sequence; for each phase, all orbital states that meet the conditions are counted, and the average orbital state is calculated as the state vector of the virtual target point corresponding to that phase; the average extrapolation time of the orbital states between adjacent phases is counted to determine the time distribution of the virtual target point.

7. The quasi-phase synchronization orbit design method based on hybrid target points as described in claim 1, characterized in that: In step 5, during the construction of the optimization problem, a threshold for the actual target correction amount is also set.

8. The quasi-phase synchronization orbit design method based on hybrid target points as described in claim 7, characterized in that: In step 6, during the solution process, only the target convergence results with correction amounts less than the actual target correction amount threshold are considered as candidate solutions. From the candidate solutions, the solution with the smallest actual target state correction amount is selected as the quasi-phase synchronization orbit. The selected solution is the orbit that satisfies the toroidal neighborhood constraint and the quasi-phase synchronization constraint. The toroidal neighborhood constraint is that the orbital state is located within the target toroidal neighborhood. For the toroidal information set T and the preset distance ε, the orbital state X satisfies d(X,T) ≤ ε, where d represents the distance. The quasi-phase synchronization constraint is that the difference between the parameterized angles of the orbit and the target orbit is less than a preset angle threshold. The target torus and its neighborhood are jointly characterized by the historical permissible torus ephemeris and the dominant phase parameter.

9. A computer-readable storage medium storing a computer program, characterized in that, The computer program causes the computer to execute the quasi-phase synchronous orbit design method based on hybrid targets as described in any one of claims 1-8.

10. An electronic device, characterized in that, include: The memory, the processor, and the computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, it implements the quasi-phase synchronization orbit design method based on hybrid targets as described in any one of claims 1-8.

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