Micro-nano satellite recovery control method for space station health inspection

Abstract

The application discloses a micro-nano satellite recovery control method for space station health inspection, which enables multiple micro-nano satellites to be recovered in sequence through design, first selects a satellite with the minimum orbit waiting time to be recovered, then calculates the difference between the orbit waiting time of all non-recovered satellites and the total time of all recovered micro-nano satellite tasks, increases the orbit waiting time of all satellites with negative difference by an integer period until the difference is negative, then selects a satellite with the minimum difference to be recovered, and repeats the previous step until all satellites are recovered. The method supplements the control method design for the recovery task of micro-nano satellites near the space station in the existing field, and is close to engineering, and can provide technical support for the subsequent micro-nano satellites to perform health detection tasks on the space station.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of spaceflight, and relates to a micro-nano satellite recovery control method for space station health patrol. BACKGROUND

[0002] With frequent human space activities, there are more and more space debris in space, thereby causing collision threats to space stations and other high-value space platforms in orbit. However, at present, when facing the collision threats of space debris, since ground control equipment cannot find these small debris, the measures that can be taken at present depend on astronaut extravehicular activities, imaging equipment on the space station, and the like. However, these measures have problems such as limited extravehicular activity space and time, and too many dead angles of the imaging equipment. In order to overcome the above problems, a micro-nano satellite formation around the space platform can be used to realize health monitoring of the space station.

[0003] In order to realize the health monitoring of the space station by the micro-nano satellite formation, a number of key technologies are needed. Since the micro-nano satellite is small in size and carries little fuel, if the micro-nano satellite formation is to be operated normally, the micro-nano satellites in the formation must be recovered in time for fuel replenishment and simple maintenance (such as shown in the figure). Figure 12 However, how to operate the micro-nano satellites correspondingly lacks corresponding research and methods. SUMMARY

[0004] The application aims to overcome the shortcomings of the prior art and provide a micro-nano satellite recovery control method for space station health patrol, so as to solve the problem in the prior art that there is no scheme for recovering, fuel replenishment, and maintenance during the normal operation of the health patrol task of the micro-nano satellite formation.

[0005] To achieve the above object, the application adopts the following technical scheme:

[0006] A micro-nano satellite recovery control method for space station health patrol, comprising the following steps:

[0007] Step 1: obtaining the orbit waiting period of each micro-nano satellite, and recovering the micro-nano satellite with the smallest orbit waiting period;

[0008] Step 2: obtaining the difference between the total time of the un-recovered micro-nano satellite and the recovered micro-nano satellite, if the difference is positive, executing step 3, otherwise, transforming the orbit waiting period of the micro-nano satellite and repeating step 2 until the difference is positive;

[0009] Step 3: recovering the micro-nano satellite corresponding to the positive difference and the smallest difference in step 2;

[0010] Step 4, repeat step 2 and step 3 until all micro-nano satellites are recovered.

[0011] Further improvements of the present application are:

[0012] Preferably, in step 1 and step 3, the recovery method of a single micro-nano satellite comprises the following steps:

[0013] S1, obtain the flight parameters of a single micro-nano satellite, and divide the relative motion period of the micro-nano satellite into N parts;

[0014] S2, based on the flight parameters, obtain the orbit planning result of the short-range rendezvous segment by solving the two-pulse optimal energy transfer problem;

[0015] S3, obtain the orbit planning result of the translation approach segment through the orbit planning result of the short-range rendezvous segment.

[0016] Preferably, in S1, the flight parameters of the single micro-nano satellite include the input space platform orbital height, the no-fly ball parameters, the maximum pulse velocity of the micro-nano satellite, the maximum transfer time of the short-range rendezvous segment, and the time when the micro-nano satellite receives the recovery instruction.

[0017] Preferably, the specific process of S2 is:

[0018] S2.1, solve the two-pulse optimal energy transfer problem corresponding to the relative position of the micro-nano satellite at any time t to obtain the pulse velocity vector of the starting position and the pulse velocity vector of the target position;

[0019] S2.2, obtain the relative orbit of the micro-nano satellite by recursively passing the pulse velocity vector of the starting position and the pulse velocity vector of the target position through the CW equation, and judge whether the relative orbit is in the no-fly ball; if the relative orbit is in the no-fly ball, execute S2.3, otherwise execute S2.4;

[0020] S2.3, let t=t+Δt, and Δt is obtained by dividing the relative motion period of the micro-nano satellite into N parts;

[0021] S2.4, calculate and store the performance index at the current time;

[0022] S2.5, repeat S2.1-S2.4, wherein the time difference between the time corresponding to the minimum performance index and the initial time is the waiting time of the orbit waiting segment, and according to the solution of the two-pulse optimal energy transfer problem corresponding to the minimum performance index in S2.4, the orbit planning result of the short-range rendezvous segment is obtained by recursively passing through the CW equation.

[0023] Preferably, the calculation formula of the two-pulse optimal energy is:

[0024]

[0025] In the formula, Δv j t represents the j-th pulse of a micro / nano satellite. r X represents the transfer time of the microsatellite, X represents a six-dimensional column vector containing the position and velocity of the microsatellite at a certain moment, and J is a performance indicator that measures the fuel consumption of the microsatellite.

[0026] The formula for calculating the performance index is as follows:

[0027] L=α1·(|Δv1|+|Δv2|)+α2·(t-t0)

[0028] In the formula, α1 and α2 are weighting coefficients representing the trade-off between fuel and time, and satisfy α1+α2=1.

[0029] Preferably, the specific process of S3 is as follows:

[0030] S3.1, Set the end state of the near-distance rendezvous segment to the initial state of the translational approach segment;

[0031] S3.2 Select the weight matrix, solve the algebraic Riccati equation, obtain the optimal state feedback control law for the translation and approach segment, and then obtain the trajectory planning result for the translation and approach segment.

[0032] Preferably, in step 2, the formula for calculating the difference between the total mission time of the unrecovered microsatellites and the recovered microsatellites is as follows:

[0033]

[0034] Where n represents the total number of recovered microsatellites and nanosatellites. This indicates that the recovered microsatellite has been placed in orbit for a period of time. This indicates the short-range rendezvous period during which the microsatellites / nano satellites have been recovered. This indicates that the recovered microsatellite has been moved closer to the target location over a period of time.

[0035] Preferably, in steps 2 and 3, the transformation formula is:

[0036]

[0037] Where T is the relative motion period of the microsatellite / nanosatellite, and m is the value that makes Δt i The smallest positive integer greater than 0.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] This invention discloses a microsatellite recovery control method for space station health monitoring. This method, designed to allow multiple microsatellites to be recovered sequentially, comprises the following main steps: 1. Calculate the orbital waiting time, rendezvous time, and translational approach time for each satellite using a single microsatellite recovery control method. 2. Select the satellite with the shortest orbital waiting time for recovery first. 3. Calculate the difference between the orbital waiting time of all unrecovered satellites and the total mission time of all recovered microsatellites, and increment the orbital waiting time of all satellites with negative differences by an integer number of periods until the difference becomes negative. 4. Select the satellite with the smallest difference for recovery, and repeat the previous step until all satellites are recovered. This method supplements existing control methods for microsatellite recovery missions near space stations, and is closely aligned with engineering practices, providing technical support for subsequent microsatellite health monitoring missions on space stations.

[0040] Furthermore, this invention designs a recovery process for a single microsatellite, dividing the recovery process into: 1. an orbital waiting period, such as... Figure 7 To avoid collision with the space station, the microsatellite, upon receiving the recovery command, can naturally move to a feasible maneuver point in its current orbit before maneuvering. 2. The near-rendezvous phase uses pulse control to complete the transfer from the feasible maneuver point to the starting point of the conical corridor. 3. The translational approach phase, such as... Figure 8 The diagram shows a forced motion from the starting point of the conical corridor to the target point of recovery, achieved using continuous control.

[0041] Furthermore, this invention designs a recovery control method for a single micro / nano satellite, the main steps of which are: 1. Calculate the maneuverable points of the micro / nano satellite over one cycle. 2. Calculate the performance index of each maneuverable point and select a suitable maneuverable point as the endpoint of the orbit waiting segment based on the performance index. 3. Calculate the orbit planning results and endpoint position (starting point of the translational approach segment) based on the selected maneuverable points. 4. Solve the control law and orbit planning results of the translational approach segment using the LQR method.

[0042] This invention introduces the concept of a "no-fly zone" to design a microsatellite recovery control method for space station health monitoring. First, based on the "no-fly zone" concept, a recovery process for a single microsatellite is designed, dividing the recovery process into an orbital waiting phase, a short-range rendezvous phase, and a translational approach phase. Second, based on the designed recovery process, a recovery control method for a single microsatellite is designed using the two-pulse optimal energy transfer problem and LQR control. Finally, considering the simultaneous recovery of multiple microsatellites, a method for calculating the recovery sequence of multiple microsatellites is designed. This method supplements existing microsatellite recovery control methods for space station health monitoring missions, and the algorithm has practical engineering applicability, providing reference and technical support for subsequent related engineering tasks. Attached Figure Description

[0043] Figure 1 This is a flowchart illustrating the design of a micro-nano satellite recovery control method for space station health monitoring according to the present invention.

[0044] Figure 2 This is a flowchart of the single micro / nano satellite recovery process of the present invention;

[0045] Figure 3 This is a flowchart illustrating the design of the single micro / nano satellite recovery control method of the present invention;

[0046] Figure 4 This is a flowchart illustrating the sequential design of the recovery order of multiple micro / nano satellites according to the present invention;

[0047] Figure 5 This is a schematic diagram of the "no-fly ball" and "recycling corridor" of the present invention;

[0048] Figure 6 This is a schematic diagram of the shape parameters of the "no-fly zone" and "recycling corridor" of the present invention;

[0049] Figure 7 This is a schematic diagram of the track waiting section and the short-range rendezvous section of the present invention;

[0050] (a) The diagram shows the short-distance meeting section; (b) The diagram shows the track waiting section;

[0051] Figure 8 This is a schematic diagram of the translational approach section of the present invention;

[0052] Figure 9 This describes the state changes of the micro-nano satellite 3 during the translation and approach phase in the single micro-nano satellite recovery control method of a specific embodiment of the present invention.

[0053] Figure 10 This describes the change in control quantity of the micro-nano satellite 3 during the translation and approach phase in the single micro-nano satellite recovery control method of a specific embodiment of the present invention.

[0054] Figure 11 The images show the orbit planning results for the simultaneous recovery of three micro- and nano-satellites in a specific embodiment of the present invention. (a) Time: 500s; (b) Time: 3000s; (c) Time: 3800s; (d) Time: 9100s.

[0055] Figure 12 This is a schematic diagram of a micro-nano satellite recovery scenario for space station health monitoring, based on the present invention. Detailed Implementation

[0056] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0057] This invention provides a control method for recovering microsatellites and nanosatellites performing health monitoring near a space station. See [link to relevant documentation]. Figure 1 The method comprises three parts: first, the design of a single micro-nano satellite recovery process based on the concept of a "no-fly ball"; second, the design of a control method for the recovery of a single micro-nano satellite, which, based on the designed recovery process, realizes the recovery control method for a single micro-nano satellite under the constraint of collision with the space station; and third, the design of the recovery sequence for multiple micro-nano satellites, which, to ensure that multiple micro-nano satellites do not collide with each other during the recovery process, realizes the successive recovery of multiple micro-nano satellites based on the recovery control method for a single micro-nano satellite.

[0058] Before delving into the specifics, it's necessary to explain the concept of a "no-fly zone." A "no-fly zone" is a broad concept, specifically comprising two parts: the "no-fly zone" itself and the "recycling corridor." For example... Figure 5 and Figure 6 The "no-fly zone" refers to a spherical area with the intersection of the two modules of the space station as the center and an appropriate distance as the radius. Microsatellites and nanosatellites are not allowed to move within this spherical area. The purpose is to prevent microsatellites and nanosatellites from colliding with the space platform when making large-scale transfers near the space station. The "recovery corridor" refers to a cone-shaped area with the recovery target point as the apex. The purpose is to ensure that when microsatellites and nanosatellites approach the recovery target point, their movement always stays within this cone-shaped area, thereby ensuring the final recovery accuracy.

[0059] One embodiment of the present invention discloses a design method for a micro-nano satellite recovery process for space station health monitoring, the design method comprising the following steps:

[0060] S1, Design a general recovery process for single micro-nano satellites used for health inspections of the space station;

[0061] S2, for a single micro-nano satellite for health inspection of the space station, based on the recovery process of S1, a specific recovery control method is designed;

[0062] S3, for multiple micro- and nano-satellites for health inspection of the space station, based on the single micro- and nano-satellite recovery control method of S2, designs a method to determine the recovery order of multiple micro- and nano-satellites.

[0063] One embodiment of the present invention discloses a method for recovering a single micro / nano satellite:

[0064] Based on the concept of a "no-fly zone," and drawing inspiration from the spacecraft rendezvous and docking mission's division of the process into three phases—long-range guidance, short-range guidance, and translational approach—to ensure docking accuracy and safety, the recovery process of microsatellites and nanosatellites is divided into an orbital waiting phase, a short-range rendezvous phase, and a translational approach phase. See also... Figure 2 The specific recovery process for a single microsatellite based on the above three stages is as follows:

[0065] S1.1, the orbital waiting period, refers to the time from when the microsatellite receives the recovery command to when it performs its first maneuver. If the microsatellite were to maneuver immediately after receiving the recovery command, there is a risk of collision with the space platform. To avoid a collision with the space station, the microsatellite can continue to orbit naturally in its current orbit, and then perform a maneuver when it reaches a feasible maneuver point.

[0066] S1.2, the short-range rendezvous phase, refers to the process by which the microsatellite performs its first maneuver to the starting point of the "recovery corridor." After the orbital waiting phase, the microsatellite is transferred to the starting point of the translational rendezvous phase, i.e., the center of the tail of the conical corridor, through pulse control.

[0067] S1.3, the translational approach phase, refers to the process from the starting point of the "recovery corridor" to the final recovery position. This phase employs continuous low-thrust control to force the microsatellite to move in a straight line until it reaches the recovery point. This phase is designed for three purposes: first, to confirm the microsatellite's status before finally approaching the recovery point; second, because the pulse control used in the close-range rendezvous phase has a certain degree of error, the translational approach phase is needed to ensure the final recovery accuracy; and third, to serve as a "buffer phase" to reduce the relatively high speed of the microsatellite relative to the space station after its maneuver.

[0068] One embodiment of the present invention discloses a method for controlling the recovery of a single micro / nano satellite, see [link to relevant documentation]. Figure 3 The method includes the following steps:

[0069] S2.1, Input the space platform orbital altitude h, no-fly ball parameters (radius R, recovery corridor opening α, recovery corridor length l), and the maximum pulse velocity Δv of the microsatellite. max The maximum transfer time t of the short-range intersection segment rmaxAnd the time t0 when the microsatellite receives the recovery command;

[0070] S2.2, the relative motion period T of the micro-nano satellite is divided into N equal segments, forming N time series with an interval of Δt;

[0071] S2.3, by solving the following dual-pulse optimal energy transfer problem corresponding to the relative position of the microsatellite at time t (initial t = t0) using equation (1), the pulse velocity vectors corresponding to the two pulses are obtained, namely the pulse at the initial position and the pulse at the target position. The relative position is the position of the microsatellite relative to the space station, specifically the position vector of the microsatellite in the LVLH coordinate system with the space station as the origin.

[0072]

[0073] In the formula, Δv j t represents the j-th pulse of a micro / nano satellite. r The transfer time of the microsatellite is represented by X, which is a six-dimensional column vector containing the position and velocity of the microsatellite at a certain moment. J is a performance indicator measuring the fuel consumption of the microsatellite; φ and φ v The specific expression is as follows, where it should be noted that φ v This is a matrix introduced during the calculation process.

[0074]

[0075]

[0076]

[0077]

[0078]

[0079] Where Δt = t2 - t1; φ(t2, t1) represents the state transition matrix, i.e., the transition from state t1 to state t2; and n is the orbital angular velocity of the space station.

[0080] S2.4: The pulse velocity vectors corresponding to the two pulses obtained in S2.3 are used to recursively calculate the relative orbit using the CW equation. The relative orbit is the orbit of the microsatellite relative to the space station. Substituting the initial state and starting pulse velocity into the analytical solution of the CW equation, all positions and velocities on the recursively calculated orbit of the microsatellite can be obtained. It is then determined whether the recursively calculated orbit enters a "no-fly zone". If the recursively calculated orbit enters a "no-fly zone", proceed to S2.5; otherwise, proceed to S2.6.

[0081] S2.5, let t = t + Δt, and return to S2.3; refers to calculating the N equally divided time points on the track in sequence to check which points will not enter the no-fly ball during the maneuver;

[0082] S2.6 defines the performance index L = α1·(|Δv1|+|Δv2|)+α2·(t-t0), where α1 and α2 are weighting coefficients representing the trade-off between fuel and time, and satisfy α1+α2=1. The first term characterizes the amount of fuel consumed during the short-range rendezvous segment, and the second term characterizes the amount of time consumed during the orbital waiting segment. Calculate and store the index L at the current moment;

[0083] S2.7, repeat S2.3 to S2.6. When t-t0=T, that is, one orbital cycle, the time difference between the time t corresponding to the minimum value of index L and the initial time is the waiting time of the orbital waiting segment. The orbital planning result of the short-distance rendezvous segment can be derived from the solution of equation (1) corresponding to this time.

[0084] S2.8, Based on the end state of the short-range rendezvous segment obtained in S2.7, take it as the initial state of the translational approach segment;

[0085] S2.9 gives the weight matrices Q and R (used to measure control effectiveness and energy consumption, respectively), solves the corresponding algebraic Riccati equation, and obtains the LQR optimal state feedback control law for the translational approach segment of the micro-nano satellite. Based on the control law, the orbit planning results for the translational approach segment can be further obtained.

[0086] One embodiment of the present invention provides a recovery sequence when multiple microsatellites are recovered simultaneously, based on the single microsatellite recovery control method. See [link to relevant documentation]. Figure 4 The specific recycling method includes the following steps:

[0087] S3.1, Based on the recovery control method for a single microsatellite, calculate the orbital waiting time for each microsatellite. Near-field intersection period and a period of translation and relocation Where i represents the number of the microsatellite;

[0088] S3.2, Select The smallest microsatellite, k, was recovered.

[0089] S3.3, Calculate the unrecovered micro / nano satellites The difference between the total time of all recovered microsatellite and nanosatellite missions (n represents the total number of recovered microsatellites and nanosatellites, This indicates that the recovered microsatellite has been placed in orbit for a period of time. This indicates the short-range rendezvous period during which the microsatellites / nano satellites have been recovered. This indicates that the recovered microsatellite has been moved and approached within a certain period of time.

[0090] S3.4, if Δt i If all are negative, then let (T is the relative motion period of the micro / nano satellite, m is the value that makes Δt) i If the smallest positive integer greater than 0 is selected, proceed to S3.3; otherwise, proceed directly to S3.5.

[0091] S3.5, take Δt i To recover the smallest and most positive micro / nano satellite, and to ensure that all Δt i negative micro-nano satellites

[0092] S3.6, repeat S3.3 to S3.5 until all microsatellites and nanosatellites are recovered, and then count the data of all microsatellites and nanosatellites. As the moment when they begin their close-range rendezvous, it corresponds to t-t0 in the performance index L in S2.6.

[0093] Example

[0094] Assuming the space station is operating in a circular orbit at an altitude of 400 km, a flight formation consisting of three microsatellites and a space platform (their relative flight orbit parameters are detailed in Table 1) is currently conducting a health monitoring mission. During the relatively long mission, the fuel of all three microsatellites will be exhausted. Therefore, it is necessary to recover these three microsatellites to the designated recovery location on the space platform (Table 1) for refueling and to carry out subsequent missions.

[0095] Table 1. Starting and Target Positions for Microsatellite Recovery

[0096]

[0097] It should be noted that, since the recovery process of a single micro-nano satellite will not change regardless of the actual situation, and since the recovery control method for a single micro-nano satellite is also included in Content 1, it will not be described separately in the specific implementation.

[0098] 1. Design of a control method for the recovery of a single micro / nano satellite

[0099] To avoid unnecessary discussion, this section only presents the design of the specific recovery control method for Microsatellite 3.

[0100] S2.1, Input the relevant parameters, see Table 2 for details:

[0101] Table 2 Recycling Control Parameters

[0102]

[0103] S2.2, the relative motion period T = 5490s of the micro-nano satellite is divided into 62 equal parts, forming 62 time series segments with an interval of 90s;

[0104] S2.3, Solve the following dual-pulse optimal energy transfer problem corresponding to the relative position of the micro / nano satellite at time t (initial t = t0):

[0105]

[0106] S2.4, use the CW equation to recursively calculate the relative orbit based on the pulse result obtained in S2.3, and determine whether the recursively calculated orbit enters the "no-fly zone". If the recursively calculated orbit enters the "no-fly zone", proceed to S2.5; otherwise, proceed to S2.6.

[0107] S2.5, let t = t + Δt, and return to S2.3;

[0108] S2.6, define the performance index L = 0.7·(|Δv1|+|Δv2|)+0.3·(t-t0), calculate and store the index L at the current time. Finally, all maneuverable points and their corresponding indices are obtained as follows:

[0109] Table 3. Maneuver Feasibility Points and Corresponding Performance Indicators

[0110]

[0111] S2.7, the performance index L is minimum at t = 450s. Therefore, t = 450s is the end time of the track waiting segment (the start time of the short-range rendezvous segment). From this, the state at the start of the short-range rendezvous segment can also be obtained as [4.0917, -28.8623, -4.0917, -0.014, -0.0041, -0.0021]. T ;

[0112] S2.8, Based on S2.7, the terminal state of the short-range intersection segment is [0,-12,0,0,0,0]. T This is taken as the initial state for translating the ridge segment;

[0113] S2.9, Select the weight matrix Q = I 6×6 And R = 5 × 10 5 ×I 3×3 Solving the corresponding algebraic Riccati equation, the optimal state feedback control law for the translational approach segment of the microsatellite is obtained as u = K·(x f -x), where the expression for matrix K is shown in the equation. Based on the control law, the state changes and control changes of the translational approach segment can be further obtained as follows: Figure 9and Figure 10 As shown.

[0114]

[0115] 3. Sequential design for the recovery of multiple microsatellites and nanosatellites

[0116] S3.1, Based on the recovery control method for a single microsatellite, the orbital waiting time for each microsatellite can be calculated. Near-field intersection period and a period of translation and relocation As shown in the table below:

[0117] Table 4. Time taken for each stage of single microsatellite / nanosatellite recovery.

[0118]

[0119] S3.2, Select The smallest microsatellite, number 3, was recovered.

[0120] S3.3 Calculate the difference between the total mission time of the unrecovered microsatellites 1 and 2 and all recovered microsatellites 3, i.e., Δt1 = 237.9352s and Δt2 = 57.9752s;

[0121] S3.4, because Δt i Therefore, it directly enters S3.5;

[0122] S3.5, take Δt i The smallest and most accurate microsatellite-nano satellite, designated as 2, was recovered.

[0123] S3.6, repeating S3.3 to S3.5, yields the difference in total mission time between the unrecovered microsatellite 1 and the recovered microsatellites 3 and 2, which is Δt1 = -424.7 s. Since Δt1 is negative, let... The final orbital waiting time for all micro and nano satellites is:

[0124] Table 5. Waiting time for simultaneous recovery of multiple microsatellites from their respective orbits.

[0125]

[0126] Meanwhile, the pulse control status of all microsatellites during the near-range rendezvous segment is as follows:

[0127] Table 6

[0128]

[0129] The final orbit planning results for the simultaneous recovery process of the three microsatellites and nanosatellites are as follows: Figure 11 As shown.

[0130] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A micro-nano satellite recovery control method for health inspection of a space station, characterized in that, Includes the following steps: Step 1: Obtain the orbital waiting time for each microsatellite and select the microsatellite with the shortest orbital waiting time for recovery. Step 2: Obtain the difference between the total mission time of the unrecovered micro-nano satellites and the recovered micro-nano satellites. If the difference is positive, proceed to Step 3. Otherwise, change the orbit of the micro-nano satellites after a waiting period and repeat Step 2 until the difference is positive. Step 3: Take the microsatellite that has the smallest positive difference value from Step 2 and recover it. Step 4: Repeat steps 2 and 3 until all microsatellites and nanosatellites have been recovered. In steps 1 and 3, the method for recovering a single microsatellite includes the following steps: S1, obtain the flight parameters of a single microsatellite and decompose the relative motion period of the microsatellite into N parts; S2, based on flight parameters, obtains the trajectory planning results for the short-range rendezvous segment by solving the optimal energy transfer problem of the double pulse; S3, the track planning results for the translation and approaching segment are obtained from the track planning results of the short-distance intersection segment; The specific process of S2 is as follows: S2.1, Solving for any time interval t The problem of optimal energy transfer of two pulses corresponding to the relative positions of micro and nano satellites is solved, and the pulse velocity vectors at the starting position and the target position are obtained. S2.2, use the pulse velocity vector at the starting position and the pulse velocity vector at the target position to recursively obtain the relative orbit of the micro-nano satellite through the CW equation, and determine whether the relative orbit is within the no-fly zone; if the relative orbit is within the no-fly zone, proceed to S2.3, otherwise proceed to S2.4; S2.3, let , This was obtained by dividing the relative motion period of micro- and nano-satellites into N parts; S2.4, calculate and store the performance metrics at the current moment; S2.5, repeat S2.1~S2.4, where the time difference between the time corresponding to the minimum performance index and the initial time is the waiting time of the orbit waiting segment. Based on the solution of the double-pulse optimal energy transfer problem corresponding to the minimum performance index in S2.4, the orbit planning result of the short-range rendezvous segment is obtained by recursion through the CW equation.

2. The microsatellite recovery control method for health inspection of a space station according to claim 1, characterized in that, In S1, the flight parameters of the single microsatellite include the orbital altitude of the input space platform, the parameters of the no-fly zone, the maximum pulse velocity of the microsatellite, the maximum transfer time of the short-range rendezvous segment, and the moment when the microsatellite receives the recovery command.

3. The microsatellite recovery control method for health inspection of a space station according to claim 2, characterized in that, The formula for calculating the optimal energy of the dual pulse is as follows: (1) In the formula, The first micro-nano satellite Subsequent pulses Indicates the transfer time of micro and nano satellites. Represents a six-dimensional column vector containing the position and velocity of micro- and nano-satellites at a given moment. It is a performance indicator for measuring the fuel consumption of micro and nano satellites; The formula for calculating the performance index is as follows: In the formula and The weighting coefficients represent the trade-off between fuel and time, and satisfy the following conditions: .

4. The microsatellite recovery control method for health inspection of a space station according to claim 1, characterized in that, The specific process of S3 is as follows: S3.1, Set the end state of the near-distance rendezvous segment to the initial state of the translational approach segment; S3.2 Select the weight matrix, solve the algebraic Riccati equation, obtain the optimal state feedback control law for the translation and approach segment, and then obtain the trajectory planning result for the translation and approach segment.

5. The microsatellite recovery control method for health inspection of a space station according to claim 1, characterized in that, In step 2, the formula for calculating the difference in total mission time between unrecovered and recovered microsatellites is as follows: in, This indicates the total number of microsatellites and nanosatellites that have been recovered. This indicates that the recovered microsatellite has been placed in orbit for a period of time. This indicates the short-range rendezvous period during which the microsatellites / nano satellites have been recovered. This indicates that the recovered microsatellite has been moved closer to the target location over a period of time.

6. The microsatellite recovery control method for health inspection of a space station according to claim 1, characterized in that, In steps 2 and 3, the transformation formula is: in, The relative motion period of micro- and nano-satellites. In order to make The smallest positive integer.

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