High-orbit different-plane target sequence approaching rendezvous planning method and system
By using hybrid coded genetic algorithm and sequence quadratic planning method in high-orbit multi-objective proximity planning, a nonlinear planning model is constructed, which solves the problems of high propellant consumption and low computational efficiency in the prior art, and achieves rapid Get the effects of rendezvous sequences and orbital change strategies.
Patent Information
- Application Number
- CN202411512703.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-28
- Publication Date
- 2025-02-18
AI Technical Summary
The prior art has high propellant consumption and low computational efficiency in high-orbit multi-target off-plan approach planning, making it difficult to quickly obtain rendezvous sequences and orbital change strategies.
The high-orbital surface target sequence approaches the in-terminal planning method, set initial parameters, determine the orbital change strategy between two adjacent targets, construct a nonlinear planning model, and solve it using a hybrid coded genetic algorithm and sequence quadratic planning method. Get the order of intersection, close observation time, and orbital change velocity increment.
The intersection sequence and orbital change strategy of quickly obtaining multi-star sequence junctions is realized, which reduces propellant consumption, improves calculation efficiency, and is of good engineering practicality.
Smart Images
Figure CN119472760A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of spacecraft orbit control, and in particular relates to a high-orbit out-of-plane target sequence approach rendezvous planning method and system. Background Art
[0002] The geostationary orbit deploys high-value satellite resources such as communications and relays, and it is of great significance to provide on-orbit services for these satellites. On-orbit inspection is the basis for providing services. The orbital planes of GEO orbit satellites vary greatly, and existing technologies are mostly aimed at co-planar approach scenarios. Co-planar approach of multiple targets requires a large consumption of propellant, which is costly and unacceptable. Summary of the invention
[0003] The technical problem solved by the present invention is to overcome the deficiencies of the prior art and provide a method and system for planning a high-orbit, non-planar target sequence approach rendezvous, which can quickly obtain a rendezvous sequence and a trajectory change strategy and has certain engineering value.
[0004] The object of the present invention is achieved through the following technical scheme: a high-orbit, non-planar target sequence approach rendezvous planning method, comprising: setting initial parameters; determining a track change strategy between two adjacent targets; constructing a nonlinear programming model according to the track change strategy between two adjacent targets; using the initial parameters, solving the nonlinear programming model based on a hybrid coding genetic algorithm to obtain a rendezvous sequence and approach observation time of each target; according to the rendezvous sequence and approach observation time of each target, using a sequential quadratic programming method to solve the speed increment for track change in the track change strategy between two adjacent targets.
[0005] In the above-mentioned high-orbit out-of-plane target sequence approach rendezvous planning method, the initial parameters include the orbit elements of the spacecraft at the initial moment and the orbit elements of each observed target at the initial moment.
[0006] In the above high-orbit non-plane target sequence approach rendezvous planning method, the orbital elements of the spacecraft at the initial moment are [a c0 ,e c0 ,i c0 ,Ω c0 ,ω c0 ,f c0 ] T ; Among them, a c0 is the semi-major axis of the spacecraft's orbit at the initial moment, e c0 is the orbital eccentricity of the spacecraft at the initial moment, i c0 is the orbital inclination of the spacecraft at the initial moment, Ω c0 is the right ascension of the ascending node of the orbit at the initial moment of the spacecraft, ω c0 is the orbital perigee argument at the initial moment of the spacecraft, f c0 is the true anomaly angle of the spacecraft orbit at the initial moment.
[0007] In the above high-orbit out-of-plane target sequence approach rendezvous planning method, the orbital element number of the i-th observed target at the initial moment is [a ti ,e ti ,i ti ,Ω ti ,ω ti ,f ti ] T ; Among them, a ti is the semi-major axis of the orbit of the i-th observation target at the initial moment, e ti is the orbital eccentricity of the i-th observation target at the initial moment, i ti is the orbital inclination of the i-th observation target at the initial moment, Ω ti is the right ascension of the orbital ascending node of the i-th observation target at the initial moment, ω ti is the orbital perigee argument of the i-th observation target at the initial moment, f ti is the true anomaly of the orbit of the i-th observed target at the initial moment, and i is a positive integer.
[0008] In the above-mentioned high-orbit out-of-plane target sequence approach rendezvous planning method, determining the trajectory change strategy between two adjacent targets includes: between the two targets, the spacecraft adopts a three-time in-plane tangential trajectory change strategy; among which, the first trajectory change is performed when the apogee is first experienced, the second trajectory change is performed when the perigee is experienced, and the third trajectory change is performed when the apogee is experienced for the last time before the rendezvous.
[0009] In the above-mentioned high-orbit out-of-plane target sequence approach rendezvous planning method, the nonlinear programming model includes optimization variables, constraints and optimization objectives; among which, the optimization variables include the rendezvous order, rendezvous time, the speed increment of three orbit change maneuvers for each target, and the last orbit change time for each target; the constraints include relative distance and solar observation illumination angle; and the optimization objective is to save the most fuel.
[0010] A high-orbit, non-planar target sequence approach rendezvous planning system comprises: a first module for setting initial parameters; a second module for determining a track change strategy between two adjacent targets; a third module for constructing a nonlinear programming model according to the track change strategy between two adjacent targets; a fourth module for solving the nonlinear programming model based on a hybrid coding genetic algorithm using the initial parameters to obtain a rendezvous sequence and approach observation time of each target; and a fifth module for solving a velocity increment for track change in the track change strategy between two adjacent targets using a sequential quadratic programming method according to the rendezvous sequence and approach observation time of each target.
[0011] In the above-mentioned high-orbit out-of-plane target sequence approach and rendezvous planning system, the initial parameters include the orbital elements of the spacecraft at the initial moment and the orbital elements of each observed target at the initial moment.
[0012] In the above high-orbit non-plane target sequence approach rendezvous planning system, the orbital elements of the spacecraft at the initial moment are [a c0 ,e c0 ,i c0 ,Ω c0 ,ω c0 ,f c0 ] T ; Among them, a c0 is the semi-major axis of the spacecraft's orbit at the initial moment, e c0 is the orbital eccentricity of the spacecraft at the initial moment, i c0 is the orbital inclination of the spacecraft at the initial moment, Ω c0 is the right ascension of the ascending node of the orbit at the initial moment of the spacecraft, ω c0 is the orbital perigee argument at the initial moment of the spacecraft, f c0 is the true anomaly of the spacecraft orbit at the initial moment; the orbital element number of the i-th observation target at the initial moment is [a ti ,e ti ,i ti ,Ω ti ,ω ti ,f ti ] T ; Among them, a ti is the semi-major axis of the orbit of the i-th observation target at the initial moment, e ti is the orbital eccentricity of the i-th observation target at the initial moment, i ti is the orbital inclination of the i-th observation target at the initial moment, Ω ti is the right ascension of the orbital ascending node of the i-th observation target at the initial moment, ω ti is the orbital perigee argument of the i-th observation target at the initial moment, f ti is the true anomaly of the orbit of the i-th observed target at the initial moment, and i is a positive integer.
[0013] In the above-mentioned high-orbit out-of-plane target sequence approach rendezvous planning system, determining the trajectory change strategy between two adjacent targets includes: between the two targets, the spacecraft adopts a three-time in-plane tangential trajectory change strategy; wherein, the first trajectory change is performed when the apogee is first experienced, the second trajectory change is performed when the perigee is experienced, and the third trajectory change is performed when the apogee is experienced for the last time before the rendezvous;
[0014] The nonlinear programming model includes optimization variables, constraints and optimization objectives; among them, the optimization variables include the rendezvous order, rendezvous time, the speed increment of three orbit change maneuvers for each target, and the last orbit change time for each target; the constraints include relative distance and solar observation illumination angle; the optimization objective is to save the most fuel.
[0015] Compared with the prior art, the present invention has the following beneficial effects:
[0016] (1) The present invention can quickly obtain the rendezvous sequence and orbit change strategy of multi-satellite sequence rendezvous by planning the rendezvous sequence and time of multiple targets in the outer layer and planning the orbit change strategy between adjacent targets in the inner layer, and has the characteristics of high calculation efficiency and good engineering practicality;
[0017] (2) The present invention can effectively solve the problem of planning the approach of multiple targets in high orbits, complete the approach of multiple targets in sequence within a specified time, and significantly reduce the propellant consumption. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:
[0019] Figure 1 It is a flow chart of a high-orbit, out-of-plane target sequence approach rendezvous planning method provided by an embodiment of the present invention. DETAILED DESCRIPTION
[0020] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to be able to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.
[0021] Figure 1 1 is a flow chart of a high-orbit, non-planar target sequence approach rendezvous planning method provided by an embodiment of the present invention. Figure 1 This embodiment provides a high-orbit, non-planar target sequence approach rendezvous planning method, the method comprising the following steps:
[0022] Step 1: Set initial parameters: determine the initial orbital parameters of the tracking vehicle and each observation target;
[0023] Step 2: Determine the three-tangential pulse orbit change strategy between two adjacent targets to complete the orbit height and phase difference adjustment;
[0024] Step 3: Establish a planning model for the approach observation of high-orbit out-of-plane target sequence, including design variables, constraints, objective functions, etc. The optimization variables include the rendezvous order, rendezvous time, the speed increment of the three orbit change maneuvers for each target, and the last orbit change time for each target. Constraints include relative distance and solar observation illumination angle. The objective function is the sum of the speed increments of the three-pulse orbit change maneuvers for each target in step 2;
[0025] Step 4: Using the orbital parameters of the spacecraft and each target in step 1, solve the optimization model based on the hybrid coding genetic algorithm to obtain the rendezvous sequence and approach observation time of each target;
[0026] Step 5: Based on the rendezvous sequence and observation time obtained in step 4, the sequential quadratic programming method is used to solve the velocity increment for changing track in the track change strategy between two adjacent targets.
[0027] For the given initial orbital conditions of the tracking aircraft and each target, a trajectory change strategy can be found so that the tracking aircraft and each target intersect at the orbital intersection in turn, satisfying the specific relative position and lighting conditions with the target aircraft.
[0028] The present invention determines a trajectory change strategy for achieving a sequential approach between a high-orbit tracking aircraft and out-of-plane targets. First, according to the mission requirements, the current orbital parameters of the tracking aircraft and each target aircraft are given. Secondly, according to the specified trajectory change strategy, a nonlinear programming model for trajectory change planning is established. An inner and outer double-layer planning solver is further constructed. The outer layer uses a hybrid coding genetic algorithm to optimize the rendezvous order and approach time. The inner layer uses a sequential quadratic programming method to solve the cubic pulse velocity increment based on the optimization results of the outer layer to minimize the total velocity increment. Orbital control is implemented according to the orbit control parameters calculated by this method, which can achieve a sequential approach to high-orbit out-of-plane targets.
[0029] The specific steps include:
[0030] Setting initial parameters
[0031] Set the initial parameters and determine the initial orbit parameters of the tracking aircraft. The orbital elements of the aircraft at the initial moment [a c0 ,e c0 ,i c0 ,Ω c0 ,ω c0 ,f c0 ] T , the number of orbital elements of each observation target i at the initial time [a ti ,e ti ,i ti ,Ω ti ,ω ti ,f ti ] T Among them, a c0is the semi-major axis of the spacecraft's orbit at the initial moment, e c0 is the orbital eccentricity of the spacecraft at the initial moment, i c0 is the orbital inclination of the spacecraft at the initial moment, Ω c0 is the right ascension of the ascending node of the orbit at the initial moment of the spacecraft, ω c0 is the orbital perigee argument at the initial moment of the spacecraft, f c0 is the true anomaly of the spacecraft orbit at the initial moment, a ti is the semi-major axis of the orbit of the observed target i at the initial moment, e ti is the orbital eccentricity of the observed target i at the initial moment, i ti is the orbital inclination of the observed target i at the initial moment, Ω ti is the right ascension of the orbital ascending node of the observed target i at the initial moment, ω ti is the orbital perigee argument of the observed target i at the initial moment, f ti is the true anomaly of the orbit of the observed target i at the initial moment.
[0032] Determine the track change strategy and parameters:
[0033] Between the two targets, the spacecraft uses a three-time in-plane tangential trajectory change strategy to complete the orbit height and phase difference adjustment. The details are as follows:
[0034] The first orbit change: a track impulse Δv1 is applied near the apogee of the N1th orbit; where N1 is the number of orbits when the apogee is first passed;
[0035] Second orbit change: Apply a track impulse Δv2 near the perigee of the N2th orbit; where N2 is N1+1;
[0036] The third orbit change: Apply a track impulse Δv3 near the apogee of the N3th orbit, where N3 is the number of orbits when the apogee is last passed before the rendezvous;
[0037] Construct a nonlinear programming model:
[0038] Firstly, a planning model for high-orbit out-of-plane target sequence approach observation is established, including design variables, constraints, objective functions, etc.
[0039] (1) Optimization variables
[0040] The optimization variables include the rendezvous order, rendezvous time, velocity increment of three orbit change maneuvers for each target, and the last orbit change time for each target.
[0041] x1=[q1 q2…q m ]
[0042] x2=[T1 T2…T m ]
[0043] x3=[Δv11 Δv 12 …Δv 1m ]
[0044] x4=[Δv 21 Δv 22 …Δv 2m ]
[0045] x5=[Δv 31 Δv 32 …Δv 3m ]
[0046] x6=[t 31 t 32 …t 3m ]
[0047] Among them, x1 is the patrol sequence of each target, x2 is the approach observation time of each target, x3, x4, x5 are the three-pulse orbit change speed increments of each target, and x6 is the last orbit change time of each target.
[0048] q m is the serial number of the mth approaching observation target, T m is the approach observation time of the mth approaching observation target, Δv 1m is the magnitude of the first track impulse of the mth approaching observation target, Δv 2m is the magnitude of the second track impulse of the mth object approaching the observation target, Δv 3m is the third track impulse magnitude of the mth observation target, t 3m is the last orbit change time of the mth approaching observation target.
[0049] (2) Constraints
[0050] After the aircraft changes its trajectory and maneuvers, when it approaches the observation target, it should meet the observation distance constraint.
[0051] |ρ i |≤ε
[0052] where ρ i is the relative position of the aircraft when it intersects with each target, and ε is the maximum observation distance.
[0053] In order to ensure that each target is under direct light observation conditions, the solar observation angle is required to be less than a certain range.
[0054]
[0055] where θ i is the solar illumination angle when the aircraft intersects with each target, defined as the angle between the relative position vector and the sun vector; sun iis the sun vector when the aircraft intersects with each target, ρ i is the relative position of the aircraft and each target when they intersect, sun i is the solar vector, and θ is the maximum solar observation angle.
[0056] (3) Objective function
[0057] If the optimization goal is to save as much fuel as possible, the objective function is the sum of the speed increments of the trajectory change.
[0058]
[0059] Where f is the objective function value, Δv ij It is the velocity increment of the jth track pulse when the aircraft approaches the target i.
[0060] Analysis shows that the rendezvous order is an integer, the rendezvous time, the speed increment of each target's three orbit change maneuvers, and the last orbit change time of each target are real numbers. This planning problem is a complex mixed integer nonlinear programming problem. A two-level programming algorithm is proposed. The outer layer is used to find the optimal patrol sequence and rendezvous time, and the inner layer is used to plan the orbit change strategy for transferring between two adjacent targets.
[0061] Solving nonlinear programming models based on hybrid coded genetic algorithm:
[0062] The outer optimization variables include intersection order and intersection time.
[0063] x1=[q1 q2 … q m ]
[0064] x2=[T1 T2 … T m ]
[0065] Among them, x1 is the patrol sequence of each target, and x2 is the approach observation time of each target.
[0066] The constraint is that the total time is less than the allowed duration of the task.
[0067] T m ≤t c
[0068] The objective function is the sum of the velocity increments of the track change.
[0069]
[0070] Where Δv i is the total velocity increment of the ith intersection, calculated by inner layer optimization.
[0071] The outer programming problem is a mixed integer nonlinear programming problem, which is solved by a hybrid coded genetic algorithm.
[0072] Solve the speed increment of the track change strategy between two adjacent targets based on sequential quadratic programming:
[0073] In the inner layer planning, the patrol sequence and rendezvous time of each target have been determined, and it is necessary to plan the track change time and maneuvering speed increment to minimize the total speed increment. This paper adopts a three-pulse tangential track change strategy to perform in-plane track transfer.
[0074] In response to the needs of inner-level planning, the following nonlinear programming model is established, which can be described as finding the optimization variable X so that the objective function is minimized while satisfying the constraints.
[0075] J = minf(X)
[0076]
[0077] Among them, J is the objective function value, f(X) is the objective function, and X is the optimization variable. is the speed of the aircraft, Φ(x,t) is the orbital dynamics model, x is the position of the aircraft, t is the orbital extrapolation time, ρ is the observed distance to the target, and ρ t is the observed distance to the target at time t, is the rate of change of the observed distance to the target, is the rate of change of the observed distance to the target at time t, Δv total is the total velocity increment required for orbit transfer, Δv max is the velocity increment constraint.
[0078] (1) Dynamic constraints
[0079] The motion state of the aircraft is represented by x, which includes 3 positions and 3 velocities. Considering the applied maneuver pulse, the motion state of the aircraft satisfies the following dynamic constraints.
[0080]
[0081] In the J2000 coordinate system, the exact dynamic model of the long-range orbit transfer problem is:
[0082]
[0083] where r and v are the position and velocity vectors, μ is the Earth's gravitational constant, is the perturbation acceleration of the Earth's oblateness J2, a sun and a moon are the perturbation accelerations of the sun and moon’s gravity respectively; a F It is the trajectory change acceleration generated by the engine thrust.
[0084] (2) Optimization variables
[0085] According to the long-distance track change model, the first pulse velocity increment Δv1, the second pulse velocity increment Δv2, the third pulse position u3 and the velocity increment Δv3 are required as the optimization variables X.
[0086] X=[Δv1 Δv2 u3 Δv3]
[0087] Where: Δv i is the speed increment of the ith track change, u i is the latitude argument at the i-th orbit change.
[0088] (3) Speed increment constraint
[0089] Assume that the maximum speed increment allowed for this task is Δv max , then the total velocity increment applied during the rendezvous process must satisfy
[0090] Δv total ≤Δv max
[0091] in: n is the total number of track changes.
[0092] (4) Track change terminal constraints
[0093] After the aircraft changes its trajectory and maneuvers, when it approaches the observation target, it should meet the observation distance constraint.
[0094] ρ i |≤ε
[0095] where ρ i is the relative position of the aircraft when it intersects with each target, and ε is the maximum observation distance.
[0096] In order to ensure that each target is under direct light observation conditions, the solar observation angle is required to be less than a certain range.
[0097]
[0098] where θ i is the solar illumination angle when the aircraft intersects with each target, defined as the angle between the relative position vector and the sun vector; sun i is the sun vector when the vehicle intersects each target.
[0099] (5) Optimization goal
[0100] If the optimization goal is to save as much fuel as possible, the objective function is the sum of the speed increments of the three orbit changes.
[0101]
[0102] The methods for solving nonlinear programming problems include penalty function method, approximate programming method, sequential quadratic programming method, etc. This paper adopts sequential quadratic programming method for simulation solution.
[0103] In response to the needs of sequential approach observation of high-orbit out-of-plane targets, this embodiment studies the multi-target sequential rendezvous planning problem. In order to reduce the orbital maneuvering speed increment requirements and avoid adjusting the orbital plane. Taking the orbital plane of the spacecraft as the reference plane, by changing the orbit within the orbital plane, aiming at the target and reaching the vicinity of the target when it passes the orbital plane intersection. After completing the patrol, continue to approach the next target until all target stars are patrolled, and finally approach multiple targets at the corresponding orbital plane intersections in turn.
[0104] In this embodiment, the spacecraft maneuvers multiple times in the orbital plane to achieve sequential encounters with multiple non-plane targets at the intersection of the orbital plane. It is necessary to plan the target rendezvous sequence, rendezvous time, and orbit change strategy. For this purpose, a two-layer planning model is established. The outer layer uses the rendezvous sequence and rendezvous time as optimization variables, which is a mixed integer programming problem and is solved using a hybrid coding genetic algorithm. After determining the rendezvous time of each target, the inner layer uses a nonlinear orbit change planning method based on sequential quadratic programming to solve the three-tangential pulse orbit change strategy for the transfer of two adjacent targets, ultimately minimizing the total orbital maneuvering speed increment. The proposed method can quickly obtain the rendezvous sequence and orbit change strategy, and has certain engineering value.
[0105] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.
Claims
1. A high-orbit, non-planar target sequence approach rendezvous planning method, characterized in that include: Set initial parameters; Determine the trajectory change strategy between two adjacent targets; Construct a nonlinear programming model based on the track change strategy between two adjacent targets; Using the initial parameters, the nonlinear programming model is solved based on the hybrid coding genetic algorithm to obtain the intersection sequence and approach observation time of each target. According to the intersection sequence and approach observation time of each target, the sequential quadratic programming method is used to solve the velocity increment for trajectory change in the trajectory change strategy between two adjacent targets.
2. The high-orbit out-of-plane target sequence approach rendezvous planning method according to claim 1 is characterized by: The initial parameters include the orbital elements of the spacecraft at the initial moment and the orbital elements of each observed target at the initial moment.
3. The high-orbit out-of-plane target sequence approach rendezvous planning method according to claim 2 is characterized by: The number of orbital elements at the initial moment of the spacecraft is [a c0 ,e c0 ,i c0 ,Ω c0 ,ω c0 ,f c0 ] T ; Among them, a c0 is the semi-major axis of the spacecraft's orbit at the initial moment, e c0 is the orbital eccentricity of the spacecraft at the initial moment, i c0 is the orbital inclination of the spacecraft at the initial moment, Ω c0 is the right ascension of the ascending node of the orbit at the initial moment of the spacecraft, ω c0 is the orbital perigee argument at the initial moment of the spacecraft, f c0 is the true anomaly angle of the spacecraft orbit at the initial moment.
4. The high-orbit out-of-plane target sequence approach rendezvous planning method according to claim 2 is characterized by: The number of orbital elements of the i-th observation target at the initial moment is [a ti ,e ti ,i ti ,Ω ti ,ω ti ,f ti ] T ; Among them, a ti is the semi-major axis of the orbit of the i-th observation target at the initial moment, e ti is the orbital eccentricity of the i-th observation target at the initial moment, i ti is the orbital inclination of the i-th observation target at the initial moment, Ω ti is the right ascension of the orbital ascending node of the i-th observation target at the initial moment, ω ti is the orbital perigee argument of the i-th observation target at the initial moment, f ti is the true anomaly of the orbit of the i-th observed target at the initial moment, and i is a positive integer.
5. The high-orbit out-of-plane target sequence approach rendezvous planning method according to claim 1, characterized in that: The strategy for determining the track change between two adjacent targets includes: Between the two targets, the spacecraft adopts a three-time in-plane tangential trajectory change strategy; the first trajectory change is performed when the vehicle first passes through the apogee, the second trajectory change is performed when the vehicle passes through the perigee, and the third trajectory change is performed when the vehicle passes through the apogee for the last time before the rendezvous.
6. The high-orbit out-of-plane target sequence approach rendezvous planning method according to claim 1, characterized in that: The nonlinear programming model includes optimization variables, constraints and optimization objectives; among them, The optimization variables include the rendezvous order, rendezvous time, velocity increment of three orbit change maneuvers for each target, and the last orbit change time for each target; The constraints include relative distance and solar observation illumination angle; The optimization goal is to save the most fuel.
7. A high-orbit, non-planar target sequence approach rendezvous planning system, characterized in that include: The first module is used to set initial parameters; The second module is used to determine the trajectory change strategy between two adjacent targets; The third module is used to construct a nonlinear programming model based on the track change strategy between two adjacent targets; The fourth module is used to solve the nonlinear programming model based on the hybrid coding genetic algorithm using the initial parameters to obtain the intersection sequence and approach observation time of each target; The fifth module is used to solve the velocity increment for changing track in the track change strategy between two adjacent targets using a sequential quadratic programming method according to the intersection order and approach observation time of each target.
8. The high-orbit out-of-plane target sequence approach rendezvous planning system according to claim 7, characterized in that: The initial parameters include the orbital elements of the spacecraft at the initial moment and the orbital elements of each observed target at the initial moment.
9. The high-orbit out-of-plane target sequence approach rendezvous planning system according to claim 8, characterized in that: The number of orbital elements at the initial moment of the spacecraft is [a c0 ,e c0 ,i c0 ,Ω c0 ,ω c0 ,f c0 ] T ; Among them, a c0 is the semi-major axis of the spacecraft's orbit at the initial moment, e c0 is the orbital eccentricity of the spacecraft at the initial moment, i c0 is the orbital inclination of the spacecraft at the initial moment, Ω c0 is the right ascension of the ascending node of the orbit at the initial moment of the spacecraft, ω c0 is the orbital perigee argument at the initial moment of the spacecraft, f c0 is the true anomaly of the orbit at the initial moment of the spacecraft; The number of orbital elements of the i-th observation target at the initial moment is [a ti ,e ti ,i ti ,Ω ti ,ω ti ,f ti ] T ; Among them, a ti is the semi-major axis of the orbit of the i-th observation target at the initial moment, e ti is the orbital eccentricity of the i-th observation target at the initial moment, i ti is the orbital inclination of the i-th observation target at the initial moment, Ω ti is the right ascension of the orbital ascending node of the i-th observation target at the initial moment, ω ti is the orbital perigee argument of the i-th observation target at the initial moment, f ti is the true anomaly of the orbit of the i-th observed target at the initial moment, and i is a positive integer.
10. The high-orbit out-of-plane target sequence approach rendezvous planning system according to claim 1, characterized in that: The strategy for determining the track change between two adjacent targets includes: Between the two targets, the spacecraft adopts a three-time in-plane tangential trajectory change strategy; the first trajectory change is performed when the vehicle first passes through the apogee, the second trajectory change is performed when the vehicle passes through the perigee, and the third trajectory change is performed when the vehicle passes through the apogee for the last time before the rendezvous. The nonlinear programming model includes optimization variables, constraints and optimization objectives; among them, The optimization variables include the rendezvous order, rendezvous time, velocity increment of three orbit change maneuvers for each target, and the last orbit change time for each target; The constraints include relative distance and solar observation illumination angle; The optimization goal is to save the most fuel.