A spacecraft dual-side intersatellite laser link space capture method and system

Abstract

The present invention discloses a method and system for capturing a spacecraft's bilateral intersatellite laser link in space. The system aims to address the technical issue of coupling the pointing degrees of freedom in existing methods of capturing a spacecraft's bilateral intersatellite laser link. The method includes acquiring key indicator data for the capture mission and determining whether the key indicator data meets a preset first capture condition, a preset second capture condition, or a preset third capture condition. Based on the corresponding capture conditions, the system then selects a guidance law coordinate system conversion method, an iterative pointing adjustment method using a spacecraft attitude control system and movable optical components, or a method for individually constraining pointing degrees of freedom to execute laser link capture, thereby generating multiple bidirectional intersatellite laser links.

Description

Technical Field

[0001] The present invention relates to the technical field of spacecraft laser capture, and in particular to a spacecraft bilateral intersatellite laser link space capture method and system. Background Art

[0002] With the development of space technology, the application of laser links between spacecraft is becoming increasingly widespread. Currently, intersatellite laser links are primarily used for intersatellite communications, but they can also be used for high-sensitivity ranging in areas such as constellation formation maintenance, gravity field measurements, and space gravitational wave detection.

[0003] Due to factors such as orbit prediction errors, errors in the adjustment and control of spacecraft pointing devices, and errors in the measurement and control of spacecraft absolute attitude, spacecraft participating in an intersatellite laser link cannot accurately determine the position of the opposing spacecraft or its own current laser pointing. Therefore, the opposing spacecraft typically exists within the pointing mechanism's coordinate system with a certain probability density. The region where the opposing spacecraft may exist with a certain probability is called the uncertainty region. When the uncertainty region is larger than the effective divergence cone angle of the outgoing beam, the spacecraft cannot directly transmit the outgoing beam to the opposing spacecraft. Therefore, before using an intersatellite laser link, space capture is usually required.

[0004] Existing methods for capturing intersatellite laser links on two sides of a spacecraft typically install each intersatellite laser optical path in a movable optical assembly, meaning there are two movable optical assemblies on the spacecraft. Because the movable optical assembly can only rotate in one dimension, in the yaw direction of the spacecraft's attitude, it cannot independently perform two-dimensional spatial scanning. Therefore, spatial scanning of the space gravitational wave detector in the pitch direction must be performed by invoking the spacecraft's attitude control system. When one of the intersatellite laser links on one side of the two-sided intersatellite laser link has completed spatial capture, the spacecraft's attitude control system and the corresponding movable optical assembly switch to tracking control mode to keep the pointing of that side aligned with the opposite spacecraft. At this point, the three pointing degrees of freedom (pitch, yaw, and roll) of the spacecraft's attitude, controlled by the spacecraft's attitude control system, cannot be directly used for spatial capture of the intersatellite laser link on the other side, resulting in coupling of the pointing degrees of freedom of the spacecraft's two-sided intersatellite laser link. Summary of the Invention

[0005] The present invention provides a method and system for spatial capture of spacecraft bilateral inter-satellite laser links, which are used to solve the technical problem of coupling of pointing degrees of freedom in spatial capture of spacecraft bilateral inter-satellite laser links caused by existing spatial capture methods of spacecraft bilateral inter-satellite laser links.

[0006] A first aspect of the present invention provides a space capture method for a spacecraft bilateral intersatellite laser link, which is applied to a spacecraft group. The method comprises:

[0007] Acquiring key indicator data of a capture task, and determining whether the key indicator data of the capture task satisfies a preset first capture condition, a preset second capture condition, or a preset third capture condition;

[0008] When the capture mission key indicator data meets the preset first capture condition, performing intersatellite laser link capture on the spacecraft group using a unilateral intersatellite laser link space capture method and a guidance law coordinate system conversion method to generate multiple bidirectional intersatellite laser links;

[0009] When the capture mission key indicator data satisfies the preset second capture condition, performing intersatellite laser link capture on the spacecraft group using a spacecraft attitude control system and a movable optical component iterative pointing adjustment method to generate multiple bidirectional intersatellite laser links;

[0010] When the key indicator data of the capture mission meets the preset third capture condition, the spacecraft group is captured using the unilateral intersatellite laser link space capture method and the pointing degree of freedom constraint method to generate multiple bidirectional intersatellite laser links.

[0011] Optionally, the spacecraft group includes a first spacecraft, a second spacecraft, and a third spacecraft; the preset guidance law includes a first guidance law; and the method of using a unilateral intersatellite laser link space capture method and a guidance law coordinate system conversion method to perform intersatellite laser link capture on multiple spacecraft to generate multiple bidirectional intersatellite laser links includes:

[0012] adjusting the orientation of the first side movable optical assembly of the second spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the first side movable optical assembly corresponding to the second spacecraft, determining the adjusted orientation of the first side movable optical assembly of the second spacecraft, and generating an outgoing light beam;

[0013] Based on the adjusted direction of the movable optical component on the first side of the second spacecraft, using the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the third spacecraft;

[0014] When the third spacecraft receives the outgoing light beam, the third spacecraft corrects the orientation of the second side movable optical component of the third spacecraft based on the outgoing light beam, and generates a retroreflected light beam to be transmitted to the second spacecraft;

[0015] When the second spacecraft receives the retroreflected light beam, the movable optical assembly on the first side of the second spacecraft is controlled to stop spatial scanning, and the adjustment direction of the movable optical assembly on the first side of the second spacecraft is corrected using the retroreflected light beam, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the third spacecraft;

[0016] performing, based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of a second side movable optical assembly corresponding to the second spacecraft, pointing adjustments of the movable optical assemblies of the second spacecraft and the first spacecraft, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft;

[0017] Based on the guidance law in the uncertainty area of ​​the yaw-pitch coordinate system of the second side movable optical component corresponding to the first spacecraft, the pointing of the movable optical components of the first spacecraft and the third spacecraft are adjusted to generate a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

[0018] Optionally, the step of adjusting the pointing directions of the movable optical components of the second spacecraft and the first spacecraft based on the guidance law in the uncertainty region in the yaw-pitch coordinate system of the second side movable optical component corresponding to the second spacecraft, and generating a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft includes:

[0019] converting the guidance law in the uncertainty region of the yaw-pitch coordinate system of the second movable optical assembly corresponding to the second spacecraft to determine the guidance law in the uncertainty region of the roll coordinate system of the bilateral pointing angle of the second movable optical assembly corresponding to the second spacecraft about the pointing angle of the first movable optical assembly;

[0020] adjusting the orientation of the second movable optical assembly on the second side of the second spacecraft based on a guidance law in an uncertainty region in a roll coordinate system around the orientation of the movable optical assembly on the first side of the second spacecraft, determining the adjusted orientation of the second movable optical assembly on the second side of the second spacecraft, and generating an outgoing light beam;

[0021] Based on the adjusted direction of the movable optical component on the second side of the second spacecraft, using the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the first spacecraft;

[0022] When the first spacecraft receives the outgoing light beam, the first spacecraft uses the outgoing light beam to correct the direction of the movable optical component on the first side of the first spacecraft, and generates a retroreflected light beam to be transmitted to the second spacecraft;

[0023] When the second spacecraft receives the reflected light beam, the second side movable optical component of the second spacecraft is controlled to stop spatial scanning, and the reflected light beam is used to correct the adjustment direction of the second side movable optical component of the second spacecraft, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft.

[0024] Optionally, the step of adjusting the pointing directions of the movable optical components of the first spacecraft and the third spacecraft based on the guidance law in the uncertainty region in the yaw-pitch coordinate system of the movable optical component on the second side corresponding to the first spacecraft, and generating a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft includes:

[0025] converting a guidance law in an uncertainty region in a yaw-pitch coordinate system of the second movable optical assembly corresponding to the first spacecraft to determine a guidance law in an uncertainty region in a roll coordinate system of a bilateral pointing angle of the second movable optical assembly corresponding to the first spacecraft and around the pointing angle of the first movable optical assembly;

[0026] Adjusting the orientation of the second movable optical assembly on the first spacecraft based on a guidance law in an uncertainty region in a roll coordinate system around the orientation of the first movable optical assembly on the second side of the first spacecraft based on the included angle of the two-side orientation of the second movable optical assembly corresponding to the first spacecraft, determining the adjusted orientation of the second movable optical assembly on the first spacecraft, and generating an outgoing light beam;

[0027] Based on the adjusted direction of the movable optical component on the second side of the first spacecraft, using the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the third spacecraft;

[0028] When the third spacecraft receives the outgoing light beam, the outgoing light beam is used to correct the direction of the movable optical component on the first side of the third spacecraft, and a retroreflected light beam is generated and transmitted to the first spacecraft;

[0029] When the first spacecraft receives the return beam, the second side movable optical component of the first spacecraft is controlled to stop spatial scanning, and the return beam is used to correct the adjustment direction of the second side movable optical component of the first spacecraft, thereby generating a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

[0030] Optionally, the method of iteratively adjusting the pointing direction of a spacecraft attitude control system and a movable optical component is used to capture the spacecraft group through an intersatellite laser link to generate multiple bidirectional intersatellite laser links, including:

[0031] adjusting the orientation of the first movable optical assembly on the second spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the first movable optical assembly on the second spacecraft, determining the adjusted orientation of the first movable optical assembly on the second spacecraft, and generating an outgoing light beam corresponding to the first movable optical assembly on the second spacecraft;

[0032] adjusting the orientation of the second side movable optical assembly of the second spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the second side movable optical assembly corresponding to the second spacecraft, determining the adjusted orientation of the second side movable optical assembly of the second spacecraft, and generating an outgoing light beam corresponding to the second side movable optical assembly of the second spacecraft;

[0033] Based on the adjusted direction of the movable optical component on the first side of the second spacecraft, using the outgoing light beam corresponding to the movable optical component on the first side of the second spacecraft to perform spatial scanning on the uncertain area corresponding to the first spacecraft;

[0034] Based on the adjusted direction of the second side movable optical component of the second spacecraft, using the outgoing light beam corresponding to the second side movable optical component of the second spacecraft to spatially scan the uncertain area corresponding to the third spacecraft;

[0035] When the third spacecraft receives the outgoing light beam corresponding to the second side movable optical assembly of the second spacecraft, the third spacecraft uses the outgoing light beam corresponding to the second side movable optical assembly of the second spacecraft to correct the direction of the second side movable optical assembly of the third spacecraft, and generates a return light beam corresponding to the second side movable optical assembly of the third spacecraft and transmits it to the second spacecraft;

[0036] When the first spacecraft receives an outgoing light beam corresponding to the first side movable optical component of the second spacecraft, the first spacecraft uses the outgoing light beam corresponding to the first side movable optical component of the second spacecraft to correct the direction of the first side movable optical component of the first spacecraft, and generates a retroreflected light beam corresponding to the first side movable optical component of the first spacecraft and transmits it to the second spacecraft;

[0037] When the second spacecraft receives the retroreflected light beam corresponding to the second side movable optical assembly of the third spacecraft and the retroreflected light beam corresponding to the first side movable optical assembly of the first spacecraft, controlling the first side movable optical assembly and the second side movable optical assembly of the second spacecraft to stop spatial scanning;

[0038] Based on the retroreflected light beam corresponding to the second side movable optical assembly of the third spacecraft and the retroreflected light beam corresponding to the first side movable optical assembly of the first spacecraft, alternately using the spacecraft attitude control system and the first side movable optical assembly and the second side movable optical assembly of the second spacecraft to iteratively correct the attitude of the second spacecraft, the adjusted orientation of the first side movable optical assembly, and the adjusted orientation of the second side movable optical assembly, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft, and a bidirectional intersatellite laser link between the second spacecraft and the third spacecraft;

[0039] adjusting the orientation of the second movable optical assembly on the first spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the second movable optical assembly corresponding to the first spacecraft, determining the adjusted orientation of the second movable optical assembly on the first spacecraft, and generating an outgoing light beam corresponding to the second movable optical assembly on the first spacecraft;

[0040] Based on the adjusted direction of the movable optical component on the second side of the first spacecraft, using the outgoing light beam corresponding to the movable optical component on the second side of the first spacecraft to perform spatial scanning on the uncertain area corresponding to the third spacecraft;

[0041] When the third spacecraft receives the outgoing light beam corresponding to the second side movable optical component of the first spacecraft, the spacecraft attitude control system and the first side movable optical component and the second side movable optical component of the third spacecraft are alternately used to iteratively correct the attitude of the third spacecraft, the adjustment direction of the first side movable optical component, and the adjustment direction of the second side movable optical component, and generate a retroreflected light beam corresponding to the first side movable optical component and the retroreflected light beam corresponding to the second side movable optical component of the third spacecraft, which are emitted to the first spacecraft;

[0042] When the first spacecraft receives the retroreflected light beam corresponding to the first side movable optical component and the retroreflected light beam corresponding to the second side movable optical component of the third spacecraft, controlling the second side movable optical component of the first spacecraft to stop spatial scanning;

[0043] Based on the reflected light beam corresponding to the first side movable optical component and the reflected light beam corresponding to the second side movable optical component of the third spacecraft, the spacecraft attitude control system and the first side movable optical component and the second side movable optical component of the first spacecraft are alternately used to iteratively correct the attitude of the first spacecraft, the direction of the first side movable optical component, and the adjusted direction of the second side movable optical component, and generate a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

[0044] Optionally, the adopting the unilateral intersatellite laser link space capture method and the pointing degree of freedom constraint method to perform intersatellite laser link capture on the spacecraft group to generate multiple bidirectional intersatellite laser links includes:

[0045] adjusting the orientation of the first side movable optical assembly of the second spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the first side movable optical assembly corresponding to the second spacecraft, determining the adjusted orientation of the first side movable optical assembly of the second spacecraft, and generating an outgoing light beam;

[0046] Based on the adjusted direction of the movable optical component on the first side of the second spacecraft, using the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the third spacecraft;

[0047] When the third spacecraft receives the outgoing light beam, the third spacecraft corrects the orientation of the second side movable optical component of the third spacecraft based on the outgoing light beam, and generates a retroreflected light beam to be transmitted to the second spacecraft;

[0048] When the second spacecraft receives the retroreflected light beam, the movable optical assembly on the first side of the second spacecraft is controlled to stop spatial scanning, and the adjustment direction of the movable optical assembly on the first side of the second spacecraft is corrected using the retroreflected light beam, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the third spacecraft;

[0049] determining a pointing error of the second side movable optical assembly of the second spacecraft based on the corrected actual direction of the outgoing light beam emitted by the first side movable optical assembly of the second spacecraft;

[0050] Determining, based on the pointing error of the second side movable optical assembly of the second spacecraft, a guidance law for the second spacecraft in an uncertainty region in a roll coordinate system around the pointing angle of the second side movable optical assembly, corresponding to the second spacecraft;

[0051] adjusting the orientation of the second movable optical assembly on the second side of the second spacecraft based on a guidance law in an uncertainty region in a roll coordinate system around the orientation of the movable optical assembly on the first side of the second spacecraft, determining the adjusted orientation of the second movable optical assembly on the second side of the second spacecraft, and generating an outgoing light beam;

[0052] Based on the adjusted direction of the movable optical component on the second side of the second spacecraft, using the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the first spacecraft;

[0053] When the first spacecraft receives the outgoing light beam, the first spacecraft corrects the orientation of the movable optical component on the first side of the first spacecraft based on the outgoing light beam, and generates a retroreflected light beam to be transmitted to the second spacecraft;

[0054] When the second spacecraft receives the retroreflected light beam, controlling the second side movable optical component of the second spacecraft to stop spatial scanning, and using the retroreflected light beam to correct the adjustment direction of the second side movable optical component of the second spacecraft, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft;

[0055] determining a pointing error of a second side movable optical assembly of the first spacecraft based on the corrected actual direction of the outgoing light beam emitted by the first side movable optical assembly of the first spacecraft;

[0056] Determining, based on the pointing error of the second movable optical assembly on the first spacecraft, a guidance law for the first spacecraft in an uncertainty region in a roll coordinate system around the pointing angle of the second movable optical assembly on both sides of the first spacecraft;

[0057] Adjusting the orientation of the second movable optical assembly on the first spacecraft based on a guidance law in an uncertainty region in a roll coordinate system around the orientation of the first movable optical assembly on the second side of the first spacecraft based on the included orientation angle of the second movable optical assembly on the first spacecraft, determining the adjusted orientation of the second movable optical assembly on the first spacecraft, and generating an outgoing light beam;

[0058] Based on the adjusted direction of the movable optical component on the second side of the first spacecraft, using the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the third spacecraft;

[0059] When the third spacecraft receives the outgoing light beam, the third spacecraft corrects the orientation of the movable optical component on the first side of the third spacecraft based on the outgoing light beam, and generates a retroreflected light beam to be transmitted to the first spacecraft;

[0060] When the first spacecraft receives the return beam, the second side movable optical component of the first spacecraft is controlled to stop spatial scanning, and the return beam is used to correct the adjustment direction of the second side movable optical component of the first spacecraft, thereby generating a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

[0061] A second aspect of the present invention provides a spacecraft dual-side intersatellite laser link space capture system, which is applied to a spacecraft group. The system includes:

[0062] An acquisition module is used to acquire key indicator data of a capture task and determine whether the key indicator data of the capture task meets a preset first capture condition, a preset second capture condition, or a preset third capture condition;

[0063] a first capture module, configured to, when the capture mission key indicator data satisfies the preset first capture condition, perform intersatellite laser link capture on the spacecraft group using a unilateral intersatellite laser link space capture method and a guidance law coordinate system conversion method, thereby generating a plurality of bidirectional intersatellite laser links;

[0064] a second capture module configured to, when the capture mission key indicator data satisfies the preset second capture condition, perform intersatellite laser link capture on the spacecraft group using a spacecraft attitude control system and a movable optical component iterative pointing adjustment method to generate multiple bidirectional intersatellite laser links;

[0065] The third capture module is used to perform intersatellite laser link capture on the spacecraft group using the unilateral intersatellite laser link space capture method and the pointing degree of freedom constraint method when the key indicator data of the capture mission meets the preset third capture condition, thereby generating multiple bidirectional intersatellite laser links.

[0066] A third aspect of the present invention provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the space capture method for a spacecraft bilateral inter-satellite laser link as described in any one of the above items.

[0067] A fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed, implements the steps of the space capture method for a spacecraft bilateral inter-satellite laser link as described in any one of the above items.

[0068] A fifth aspect of the present invention provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions, wherein when the program instructions are executed by a computer, the computer is caused to perform the steps of the space capture method for a spacecraft bilateral inter-satellite laser link as described in any one of the above items.

[0069] It can be seen from the above technical solutions that the present invention has the following advantages:

[0070] The above technical solution of the present invention provides a spacecraft bilateral intersatellite laser link space capture method, which is applied to a spacecraft group. First, key indicator data of the capture mission is obtained, and it is judged whether the key indicator data of the capture mission meets the preset first capture condition, the preset second capture condition or the preset third capture condition; then, when the key indicator data of the capture mission meets the preset first capture condition, the spacecraft group is captured with an intersatellite laser link by using a unilateral intersatellite laser link space capture method and a guidance law coordinate system conversion method, and a plurality of bidirectional intersatellite laser links are generated; when the key indicator data of the capture mission meets the preset second capture condition, the spacecraft attitude control system and the movable optical component iterative pointing adjustment method are used to capture the spacecraft group with an intersatellite laser link, and a plurality of bidirectional intersatellite laser links are generated; finally, when the key indicator data of the capture mission meets the preset third capture condition, the spacecraft group is captured with an intersatellite laser link by using a guidance law coordinate system conversion method. A single-sided intersatellite laser link space capture method and a method for constraining the pointing degrees of freedom one by one are used to capture the intersatellite laser link of a spacecraft group to generate multiple bidirectional intersatellite laser links. Based on the above scheme, it is judged whether the acquired key indicator data of the capture mission meets the preset first capture condition, the preset second capture condition or the preset third capture condition, and then according to the satisfied corresponding capture conditions, the corresponding method is adopted to execute laser link capture to generate multiple bidirectional intersatellite laser links. Based on the specific capture conditions, the present invention selects a single-sided intersatellite laser link space capture method, a guidance law coordinate system conversion method, a spacecraft attitude control system and a movable optical component iteratively adjusting the pointing method, and a method for constraining the pointing degrees of freedom one by one, which can realize the decoupling of the pointing degrees of freedom in the space capture of the spacecraft's bilateral intersatellite laser link, thereby achieving the purpose of realizing the space capture of the spacecraft's bilateral intersatellite laser link. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0072] Figure 1 A flowchart of the steps of a spacecraft bilateral intersatellite laser link space capture method provided in Example 1 of the present invention;

[0073] Figure 2 A schematic diagram of an inter-satellite laser link in a typical triangular constellation provided in the first embodiment of the present invention;

[0074] Figure 3 A flowchart of the steps for performing intersatellite laser link space capture using a unilateral intersatellite laser link space capture method and a guidance law coordinate system conversion method, provided in the second embodiment of the present invention;

[0075] Figure 4 A schematic diagram of the concepts on a single spacecraft involved in the guidance law coordinate system conversion method provided in the second embodiment of the present invention;

[0076] Figure 5 A flow chart of bidirectional intersatellite laser link space capture for performing second-side intersatellite laser link space capture using a guidance law coordinate system conversion method provided in the second embodiment of the present invention;

[0077] Figure 6 A flowchart of the steps for performing space capture of an intersatellite laser link using a spacecraft attitude control system and a movable optical component iterative pointing adjustment method, provided in the third embodiment of the present invention;

[0078] Figure 7 A schematic diagram of the concepts on a single spacecraft involved in the spacecraft attitude control system and the method for iteratively adjusting the pointing direction of a movable optical component provided in the third embodiment of the present invention;

[0079] Figure 8 A flowchart of a bilateral bidirectional intersatellite laser link space capture method using a spacecraft attitude control system and a movable optical component to iteratively adjust the pointing direction of a bilateral intersatellite laser link provided in the third embodiment of the present invention;

[0080] Figure 9 A flowchart of the steps for performing intersatellite laser link capture using the one-sided intersatellite laser link space capture method and the pointing degree of freedom constraint method provided in the fourth embodiment of the present invention;

[0081] Figure 10 A schematic diagram of the concepts on a single spacecraft involved in the method for constraining the pointing degrees of freedom one by one provided in the fourth embodiment of the present invention;

[0082] Figure 11 A flow chart of a bidirectional intersatellite laser link space capture for performing space capture of a second-side intersatellite laser link using a method of constraining the pointing degrees of freedom one by one, provided in the fourth embodiment of the present invention;

[0083] Figure 12 This is a structural block diagram of a spacecraft dual-side intersatellite laser link space capture system provided in Example 5 of the present invention;

[0084] Wherein, the following are the explanations of the reference numerals: 2-1, spacecraft No. 1 (first spacecraft); 2-2, spacecraft No. 2 (second spacecraft); 2-3, spacecraft No. 3 (third spacecraft); 2-4, movable optical assembly on the first side of spacecraft No. 1; 2-5, movable optical assembly on the second side of spacecraft No. 1; 2-6, movable optical assembly on the first side of spacecraft No. 2; 2-7, movable optical assembly on the second side of spacecraft No. 2; 2-8, movable optical assembly on the first side of spacecraft No. 3; 2-9, movable optical assembly on the second side of spacecraft No. 3; 2-10, intersatellite laser link L1; 2-11, intersatellite laser link L1'; 2-12, intersatellite laser link L2; 2-13, intersatellite laser link L2'; 2-14, intersatellite laser link L3; 2-15, intersatellite laser link L3'; 1. Movable optical component on the first side; 2. Movable optical component on the second side; 3. Direction of movable optical component on the first side; 4. Direction of movable optical component on the second side; 5. Yaw direction of movable optical component on the first side; 6. Pitch direction of movable optical component on the first side; 7. Yaw direction of movable optical component on the second side; 8. Pitch direction of movable optical component on the second side; 9. Roll direction around the direction of movable optical component on the first side; 10. Direction of angle between two sides; 11. Uncertain area in yaw-pitch coordinate system of movable optical component on the first side; 12. Uncertain area in yaw-pitch coordinate system of movable optical component on the second side; 13. Uncertain area in roll coordinate system of two sides pointing angle between movable optical component on the second side; 14. Spacecraft. DETAILED DESCRIPTION

[0085] The embodiments of the present invention provide a method and system for spatial capture of spacecraft bilateral inter-satellite laser links, which are used to solve the technical problem of coupling of pointing degrees of freedom in spatial capture of spacecraft bilateral inter-satellite laser links caused by existing spacecraft bilateral inter-satellite laser link spatial capture methods.

[0086] In order to make the purpose, features, and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0087] See also Figure 1 , Figure 1 This is a flowchart of the steps of a spacecraft bilateral inter-satellite laser link space capture method provided in Example 1 of the present invention.

[0088] The present invention provides a spacecraft bilateral intersatellite laser link space capture method, which is applied to a spacecraft group, and includes:

[0089] Step 101: Acquire key indicator data of a capture task, and determine whether the key indicator data of the capture task meets a preset first capture condition, a preset second capture condition, or a preset third capture condition.

[0090] The key indicator data of the capture mission include the installation matrix error of the movable optical component, the time required to perform the capture mission, the propellant consumption, and the time required to perform the capture mission using the guidance law coordinate system conversion method.

[0091] Please note that Figure 2 The spacecraft group includes three spacecraft (i.e., a first spacecraft, a second spacecraft, and a third spacecraft), each of which is equipped with two movable optical components, and two intersatellite laser links (bidirectional intersatellite laser links) are formed between the two spacecraft through the movable optical components.

[0092] Step 102: When the key indicator data of the capture mission meets the preset first capture condition, the spacecraft group is captured using the unilateral intersatellite laser link space capture method and the guidance law coordinate system conversion method to generate multiple bidirectional intersatellite laser links.

[0093] It should be noted that the preset first capture condition is that when the installation matrix error of the movable optical component is less than 1% of the uncertainty area, the time required to execute the capture mission is less than or equal to the capture window time on the orbit, and the propellant consumption is less than or equal to the propellant consumption pre-allocated for the capture mission, it indicates that the key indicator data of the capture mission meets the preset first capture condition, and the unilateral intersatellite laser link space capture method and the guidance law coordinate system conversion method are preferably used.

[0094] Furthermore, the guidance law coordinate system conversion method refers to that after the capture of the first-side intersatellite laser link is completed, the space scanning guidance law formulated in the two-dimensional yaw-pitch coordinate system of the second-side movable optical component body coordinate system is converted to the "bilateral pointing angle-roll around the pointing of the first-side movable optical component" coordinate system, and the second-side movable optical component executes the pointing adjustment component in the direction of the bilateral pointing angle, and the spacecraft attitude control system executes the pointing adjustment component in the direction of the roll around the pointing of the first-side movable optical component, thereby realizing the execution of the same space scanning guidance law as the first-side intersatellite laser link in the second-side movable optical component body coordinate system to complete space capture.

[0095] This method can be considered a basic decoupling method for dual-side intersatellite laser link space capture. Its advantage lies in making the second-side intersatellite laser link space capture mission equivalent to a single-side intersatellite laser link space capture mission. This allows all intersatellite laser link space capture missions in the constellation to reuse the same single-side intersatellite laser link capture mission process and guidance law, reducing the design difficulty of the constellation intersatellite laser link capture scheme. A drawback of this method is the low accuracy of the guidance law execution. In particular, when the installation matrix of the movable optical assembly in the spacecraft body coordinate system has unknown errors, the conversion matrix from the two-dimensional yaw-pitch coordinate system of the second-side movable optical assembly body coordinate system to the dual-side pointing angle-roll coordinate system around the first-side movable optical assembly pointing will have unknown errors. Furthermore, because the pointing of the first-side movable optical assembly also has unknown errors in the spacecraft body coordinate system, the spacecraft attitude control system cannot accurately adjust the spacecraft attitude to roll around the first-side movable optical assembly pointing. These unknown errors reduce the accuracy of the guidance law execution for the second-side intersatellite laser link space scan, increasing the risk of missed scans in the space scan. Another drawback of this method is its high time and propellant consumption costs. This is because the guidance law for the single-sided intersatellite laser link space scan used in this method is optimized for the single-sided intersatellite laser link space capture mission and is generally not optimal for the second-side intersatellite laser link space capture mission. In particular, the first-side intersatellite laser link, which has already completed space capture, can provide additional pointing correction information for the second-side intersatellite laser link space capture mission. Under such conditions, applying the guidance law for the single-sided intersatellite laser link space scan to the second-side intersatellite laser link space capture mission will result in scanning some scan points that can be excluded and no longer need to be scanned. Another drawback of this method is the risk of controller conflict. Different controllers for the movable optical assembly and the spacecraft attitude are prone to coupling and even conflict, especially when the controllers for the movable optical assembly and the spacecraft attitude each have closed-loop feedback control for pointing. Based on the above advantages and disadvantages, the guidance law coordinate system transformation method is suitable for tasks where the movable optical components are installed with sufficient precision or the installation matrix of the movable optical components can be accurately measured on-orbit, is insensitive to the time consumption cost and propellant consumption cost of the space scanning process, and is capable of designing appropriate multi-controller collaborative pointing control schemes.

[0096] Step 103: When the key indicator data of the capture mission meets the preset second capture condition, the spacecraft attitude control system and the movable optical component iterative pointing adjustment method are used to capture the spacecraft group through intersatellite laser links to generate multiple bidirectional intersatellite laser links.

[0097] It should be noted that the preset second capture condition is that when the installation matrix error of the movable optical component is greater than or equal to 1% of the uncertainty area, it indicates that the key indicator data of the mission meets the preset second capture condition, and the spacecraft attitude control system and the movable optical component iterative adjustment pointing method are preferred.

[0098] Furthermore, the method for iteratively adjusting the pointing of the spacecraft attitude control system and the movable optical component refers to designing an appropriate constellation inter-satellite laser link capture process so that all spacecraft do not need to complete the space capture of the inter-satellite laser link on one side before performing the space capture of the inter-satellite laser link on the other side, but first complete the bilateral space scan and then measure the incident angle of the bilateral return light beams, to ensure that each spacecraft can simultaneously obtain continuous irradiation of the return light beams on both sides when performing the spacecraft attitude and pointing correction of the movable optical component. On this basis, the spacecraft attitude control system and the movable optical component are used alternately to iteratively adjust the spacecraft attitude and the bilateral pointing angle until the bilateral pointing is adjusted to the correct value within the tolerance range at the same time.

[0099] One advantage of this method is its high reliability. The spacecraft attitude control system and the movable optical assembly alternately control the pointing direction, eliminating the need for coordinated control of the two controllers. This avoids complex controller design and the risk of controller coupling and conflict. Another advantage is that the method requires low precision for the movable optical assembly's mounting matrix in the spacecraft coordinate system. Theoretically, even if the movable optical assembly's mounting matrix in the spacecraft coordinate system has large unknown errors, making it impossible for the movable optical assembly to coordinate with the spacecraft attitude control system, as long as the spacecraft attitude control system and the movable optical assembly each independently adjust the pointing direction to minimize the bilateral pointing error, the spacecraft attitude and the bilateral pointing angle will converge to their unique correct values ​​with increasing iterations. A drawback of this method is that the constellation capture process is complex and the capture scheme design is difficult. Designing an appropriate capture process may be difficult in constellations with complex intersatellite laser link structures. Given these advantages and disadvantages, this method of iteratively adjusting the pointing direction of the spacecraft attitude control system and the movable optical assembly is suitable for missions with high reliability requirements, low precision of the movable optical assembly mounting matrix, and simple intersatellite laser link structures.

[0100] Spacecraft that use iterative pointing adjustments using a spacecraft attitude control system and movable optical components are generally unsuitable for coordinated pointing control. Therefore, guidance laws that adjust pointing in only one direction at a time, such as line scanning or rectangular scanning, are preferred over guidance laws generally considered optimal, such as equidistant spiral scanning or hexagonal scanning. The spatial scanning of the bilateral uncertainty region can be performed sequentially or simultaneously. When performing bilateral uncertain area space scanning in sequence, it is particularly emphasized that when the capture sensor on one side receives the reflected light beam emitted by the receiving spacecraft, no pointing correction is performed and the tracking control mode is not entered, but the space scanning on the other side is performed instead until the capture sensors on both sides receive the reflected light beam at the same time; when performing bilateral uncertain area space scanning at the same time, it is particularly emphasized that the guidance laws on both sides must be synchronized in their respective pitch directions, and the spacecraft attitude is controlled by the spacecraft attitude control system to perform the pitch adjustment of bilateral pointing at the same time. Since the pitch axis of the spacecraft attitude cannot be simultaneously aligned with the pitch axis of the first side movable optical component and the second side movable optical component when adjusting the pitch of bilateral pointing at the same time, parasitic pointing adjustment in the yaw direction of bilateral pointing will be caused when performing the pitch adjustment of bilateral pointing. Therefore, a guidance law that is insensitive to parasitic pointing adjustment in the yaw direction, such as branch scanning, is preferred.

[0101] Step 104: When the key indicator data of the capture mission meets the preset third capture condition, the intersatellite laser link capture of the spacecraft group is performed using the unilateral intersatellite laser link space capture method and the pointing degree of freedom constraint method to generate multiple bidirectional intersatellite laser links.

[0102] It should be noted that the preset third capture condition is that when the time required to perform the capture mission using the guidance law coordinate system conversion method is greater than the capture window time on the orbit, or the propellant consumption is greater than the propellant consumption pre-allocated for the capture mission, it indicates that the key indicator data of the capture mission meets the preset third capture condition, and the unilateral intersatellite laser link space capture method and the pointing degree of freedom constraint method are preferred.

[0103] Furthermore, the method of constraining the pointing degrees of freedom one by one refers to formulating the space-scanning guidance law for the second-side intersatellite laser link based on the principle of traversing the parameter space of the pointing degrees of freedom, rather than the conventional method of formulating the space-scanning guidance law in the two-dimensional yaw-pitch coordinate system of the second-side movable optical assembly body. The space capture process is the process of finding a correct combination of pointing execution values. Under a certain capture success rate requirement, the possible correct execution values ​​of all pointing degrees of freedom form a finite parameter space, and one or more pointing execution value combinations in this parameter space are correct. When the first intersatellite laser link in the dual-sided intersatellite laser link has completed space capture, the execution values ​​of the pitch and yaw directions of the spacecraft attitude (based on the pointing direction of the first-side movable optical component) and the one-dimensional pointing execution value of the first-side movable optical component in the spacecraft attitude yaw direction have been fully constrained. These three pointing execution values ​​are part of a correct pointing execution value combination. At this time, the second-side intersatellite laser link only needs to traverse the remaining parameter space of the remaining two underconstrained pointing degrees of freedom (the one-dimensional pointing execution value of the second-side movable optical component in the spacecraft attitude yaw direction and the roll around the pointing direction of the first-side movable optical component) to complete the space scan, without having to implement the same guidance law as the first-side intersatellite laser link.

[0104] This method specifically emphasizes that the remaining parameter space for the two underconstrained pointing degrees of freedom is generally smaller than the parameter space achievable by the same guidance law as the first-side intersatellite laser link. When formulating the guidance law within this remaining parameter space (i.e., the one-dimensional pointing execution value of the second-side movable optical assembly in the spacecraft attitude yaw direction, in the roll coordinate system around the first-side movable optical assembly), this method can choose, based on the actual conditions of the spacecraft attitude control system and the second-side movable optical assembly controller, a guidance law that relies on coordinated pointing control or an alternate pointing control law between the two. One advantage of this method is that it minimizes time and propellant consumption because it avoids spatial scanning of ineffective areas, minimizing the number of scanning points used in the spatial scanning process. Another advantage is that this method is insensitive to the accuracy of data such as the movable optical assembly mounting matrix, as it does not require coordinate system transformations for the guidance law. A drawback of this method is that it increases the difficulty of constellation capture scheme design, requiring the design of two different guidance laws for the dual-side intersatellite laser link space capture mission and requiring a detailed breakdown and precise estimation of the components of the pointing error. Based on the above advantages and disadvantages, the method of constraining the degrees of freedom one by one is suitable for tasks that are sensitive to the time consumption cost and propellant consumption cost of the capture process.

[0105] For comparison purposes, the existing technologies can be used as a reference. A typical implementation of space capture involves the transmitting spacecraft actuating its pointing mechanism to adjust its pointing direction, causing the outgoing beam to follow a pre-set trajectory within the two-dimensional yaw-pitch coordinate system of the pointing mechanism's main coordinate system. This allows for spatial scanning of the uncertainty region within the receiving spacecraft until the uncertainty region is covered. This pre-set trajectory is called a guidance law, which is typically proactively formulated by the capture solution designer within the two-dimensional yaw-pitch coordinate system of the pointing mechanism's main coordinate system based on the extent of the uncertainty region and other factors. While the transmitting spacecraft performs the spatial scan, the receiving spacecraft uses a capture sensor to receive the laser beam from the transmitting spacecraft. At some point during the transmitting spacecraft's spatial scan, the capture sensor on the receiving spacecraft is temporarily illuminated by the laser beam. The capture sensor on the receiving spacecraft then measures the incident angle of the incoming beam and, based on the measurement results, accurately corrects the pointing direction of its own pointing mechanism before accurately transmitting a return beam back to the transmitting spacecraft. The capture sensor on the transmitting spacecraft measures the incident angle of the reflected beam and, based on the measurement results, accurately adjusts the pointing direction of its own pointing mechanism, accurately transmitting the outgoing beam to the receiving spacecraft, thereby establishing a bidirectional intersatellite laser link. Once the bidirectional intersatellite laser link is established, the pointing mechanisms of the transmitting and receiving spacecraft can each continuously track the incident angle of the incoming beam they receive, thereby maintaining the laser link.

[0106] The spacecraft attitude control system is the most basic pointing mechanism, adjusting the orientation of the intersatellite laser optical path, which is fixed to the spacecraft platform, by controlling the spacecraft's attitude. The spacecraft attitude control system provides three degrees of freedom (DOF) for the spacecraft's attitude: pitch, yaw, and roll. This is sufficient to achieve spatial capture of a single opposing spacecraft. However, in constellation formations, a spacecraft may need to capture more than one opposing spacecraft, and the angle between the orientations of two (or more) opposing spacecraft is often not fixed. Therefore, additional DOFs are required. For spacecraft requiring bilateral intersatellite laser link spatial capture, at least one degree of freedom (DOF) is required to enable two-dimensional spatial scanning on both sides. Therefore, four DOFs are the minimum required for bilateral spatial capture.

[0107] Existing intersatellite laser link technologies or products typically increase the pointing freedom by installing a dedicated two-dimensional rapid pointing mechanism for each side of the intersatellite laser link, ensuring that each side of the intersatellite laser link can complete two-dimensional space scanning without invoking the spacecraft's attitude control system. This design avoids the problem of coupling the pointing freedom of bilateral intersatellite laser link space capture by excessively increasing the pointing freedom. Dedicated rapid pointing mechanisms are usually composed of gimbals, periscope-type optical systems, rapid deflection mirrors, etc. In addition to increasing the pointing freedom, installing a dedicated rapid pointing mechanism can also significantly reduce the difficulty, time consumption, and propellant consumption of space capture missions. However, it will also increase the manufacturing and adjustment costs of the spacecraft, technical difficulties, risks, and optical path noise in the intersatellite laser link.

[0108] Space-based gravitational wave detection missions are a typical example of space missions that utilize constellation formations and intersatellite laser link technology. Typically, three spacecraft form a triangular constellation to perform high-sensitivity intersatellite laser interferometer ranging (LIIR) to detect gravitational wave signals. For high-sensitivity space-based gravitational wave detectors, such as China's Tianqin and Taiji missions, and Europe's Laser Interferometer Space Antenna (LISA) program, dedicated rapid pointing mechanisms can induce optical path tilt within the LIR optical path, leading to changes in the optical path length to be measured. This is known as the tilt-length coupling effect. This tilt-length coupling effect can severely interfere with the scientific measurement mission of space-based gravitational wave detectors. Therefore, these detectors cannot increase their pointing freedom by installing conventional dedicated rapid pointing mechanisms. For these space-based gravitational wave detectors, the source of pointing freedom, in addition to the spacecraft attitude control system, is a highly stable movable optical assembly capable of one-dimensional rotation in the spacecraft's attitude yaw direction. This movable optical assembly incorporates the entire scientific measurement optical path and rotates with it, thereby preventing optical path tilt and, consequently, the tilt-length coupling effect. The movable optical assembly, which contains the entire scientific measurement optical path and rotates together, also means that the capture sensor's line of sight and the emission direction of the outgoing beam are synchronously corrected. That is, when the incident angle of the incident beam on the capture sensor is corrected, the emission direction error of the outgoing beam is also corrected. For spacecraft with dual-sided intersatellite laser links, each intersatellite laser optical path is typically installed in a movable optical assembly, meaning that there are two movable optical assemblies on the spacecraft. Because the movable optical assembly can only rotate in one dimension in the spacecraft's yaw direction and cannot independently perform two-dimensional spatial scanning, the spacecraft's spatial scanning in the pitch direction must be performed by calling the spacecraft's attitude control system. When one of the intersatellite laser links on one side has completed space capture, the spacecraft attitude control system and the corresponding movable optical components switch to tracking control mode to keep the pointing of this side continuously aligned with the opposite spacecraft. At this time, the three pointing degrees of freedom of the spacecraft attitude pitch, yaw, and roll controlled by the spacecraft attitude control system cannot be directly used for the space capture of the intersatellite laser link on the other side, thus resulting in the problem of coupling of the pointing degrees of freedom of the space capture of the two-sided intersatellite laser links on the spacecraft.

[0109] In response to the above problems, the present invention proposes a method for space capture of spacecraft bilateral intersatellite laser links, which can overcome the problem of coupling of pointing degrees of freedom in space capture of spacecraft bilateral intersatellite laser links, thereby realizing a feasible method for space capture of bilateral intersatellite laser links. Specifically, based on the specific capture target and capture conditions, one or more of the three methods of guidance law coordinate system conversion method, spacecraft attitude control system and movable optical component iterative pointing adjustment method, and pointing degree of freedom one by one constraint method are selected, which can realize decoupling of pointing degrees of freedom in space capture of spacecraft bilateral intersatellite laser links, thereby achieving the purpose of space capture of spacecraft bilateral intersatellite laser links.

[0110] In an embodiment of the present invention, a spacecraft bilateral intersatellite laser link space capture method is provided, which is applied to a spacecraft group. First, key indicator data of the capture mission is obtained, and it is determined whether the key indicator data of the capture mission meets the preset first capture condition, the preset second capture condition or the preset third capture condition. Then, when the key indicator data of the capture mission meets the preset first capture condition, a single-sided intersatellite laser link space capture method and a guidance law coordinate system conversion method are used to perform laser link capture on the spacecraft group to generate multiple bidirectional intersatellite laser links. When the key indicator data of the capture mission meets the preset second capture condition, a spacecraft attitude control system and a movable optical component iterative pointing adjustment method are used to perform laser link capture on the spacecraft group to generate multiple bidirectional intersatellite laser links. Finally, when the key indicator data of the capture mission meets the preset third capture condition, a single-sided intersatellite laser link space capture method and a guidance law coordinate system conversion method are used to perform laser link capture on the spacecraft group to generate multiple bidirectional intersatellite laser links. A single-sided intersatellite laser link space capture method and a method for constraining the pointing degrees of freedom one by one are used to perform laser link capture on a spacecraft group to generate multiple bidirectional intersatellite laser links. Based on the above scheme, it is determined whether the acquired key indicator data of the capture mission meets the preset first capture condition, the preset second capture condition or the preset third capture condition, and then according to the satisfied corresponding capture conditions, the corresponding method is used to execute laser link capture to generate multiple bidirectional intersatellite laser links. Based on the specific capture conditions, the present invention selects a single-sided intersatellite laser link space capture method, a guidance law coordinate system conversion method, a spacecraft attitude control system and a movable optical component iteratively adjusting the pointing method, and a method for constraining the pointing degrees of freedom one by one, which can realize the decoupling of the pointing degrees of freedom in the space capture of the spacecraft's bilateral intersatellite laser link, thereby achieving the purpose of realizing the space capture of the spacecraft's bilateral intersatellite laser link.

[0111] See also Figure 3 , Figure 3 A flowchart of the steps for performing intersatellite laser link space capture using a unilateral intersatellite laser link space capture method and a guidance law coordinate system conversion method is provided for the second embodiment of the present invention. The process may include the following steps:

[0112] Step 301: Based on the guidance law in the uncertainty area in the yaw-pitch coordinate system of the first side movable optical component corresponding to the second spacecraft, adjust the direction of the first side movable optical component of the second spacecraft, determine the adjusted direction of the first side movable optical component of the second spacecraft, and generate an outgoing light beam.

[0113] Step 302: Based on the adjusted direction of the movable optical component on the first side of the second spacecraft, use the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the third spacecraft.

[0114] Step 303: When the third spacecraft receives the outgoing light beam, the direction of the movable optical component on the second side of the third spacecraft is corrected based on the outgoing light beam, and a retroreflected light beam is generated and transmitted to the second spacecraft.

[0115] Step 304: When the second spacecraft receives the reflected light beam, the movable optical component on the first side of the second spacecraft is controlled to stop spatial scanning, and the adjusted direction of the movable optical component on the first side of the second spacecraft is corrected using the reflected light beam to generate a bidirectional intersatellite laser link between the second spacecraft and the third spacecraft.

[0116] Please note that Figure 4, for a general unilateral intersatellite laser link space capture method (unilateral intersatellite laser link space capture method), a space capture of a bidirectional intersatellite laser link consisting of the intersatellite laser link L1 (2-10) and the intersatellite laser link L1' (2-11) (i.e., a bidirectional intersatellite laser link between the second spacecraft and the third spacecraft) is performed. Spacecraft No. 2 2-2 (the second spacecraft) serves as the transmitting spacecraft. According to the guidance law in the uncertainty area in the yaw-pitch coordinate system of the first side movable optical component corresponding to the second spacecraft (that is, the guidance law in the uncertainty area 11 in the yaw-pitch coordinate system of the first side movable optical component), the spacecraft actively adjusts the pointing direction 3 of the first side movable optical component, that is, adjusts the pointing direction of the first side movable optical component of the second spacecraft, and generates an outgoing light beam. Based on the adjusted pointing direction, the outgoing light beam is used to perform spatial scanning of the uncertainty area corresponding to the third spacecraft (that is, the uncertainty area 11 in the yaw-pitch coordinate system of the first side movable optical component), wherein the pointing adjustment component in the yaw direction 5 of the first side movable optical component is executed by the first side movable optical component 1, and the pointing adjustment component in the pitch direction 6 of the first side movable optical component is executed by controlling the attitude of the spacecraft 14 by the spacecraft attitude control system. At some point during this process, spacecraft 3 2-3 (the third spacecraft), acting as the receiving spacecraft, received the outgoing beam from spacecraft 2 2-2. It then corrected the pointing direction of spacecraft 3's second-side movable optical assembly 2-9 and sent a return beam back to spacecraft 2 2-2. After receiving the return beam, spacecraft 2 2-2 stopped its spatial scan and corrected the pointing direction of spacecraft 2's first-side movable optical assembly 2-6. This completed the spatial capture of the bidirectional intersatellite laser link consisting of intersatellite laser link L1 (2-10) and intersatellite laser link L1' (2-11).

[0117] Step 305: Based on the guidance law in the uncertainty region in the yaw-pitch coordinate system of the second side movable optical component corresponding to the second spacecraft, the pointing of the movable optical components of the second spacecraft and the first spacecraft are adjusted to generate a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft.

[0118] Specifically, step 305 may include the following sub-steps S51-S55:

[0119] Step S51: converting the guidance law in the uncertainty region of the yaw-pitch coordinate system of the second movable optical assembly corresponding to the second spacecraft to determine the guidance law in the uncertainty region of the roll coordinate system of the second movable optical assembly's bilateral pointing angle around the first movable optical assembly's pointing angle.

[0120] Step S52: Based on the guidance law in the uncertainty region in the roll coordinate system around the pointing of the second movable optical component on the first side of the second spacecraft, the pointing of the second movable optical component on the second side of the second spacecraft is adjusted based on the included pointing angle of the second movable optical component on both sides of the second spacecraft, the adjusted pointing of the second movable optical component on the second side of the second spacecraft is determined, and an outgoing light beam is generated.

[0121] Step S53: Based on the adjusted direction of the movable optical component on the second side of the second spacecraft, the outgoing light beam is used to perform spatial scanning on the uncertain area corresponding to the first spacecraft;

[0122] Step S54: When the first spacecraft receives the outgoing light beam, the outgoing light beam is used to correct the direction of the movable optical component on the first side of the first spacecraft, and a retroreflected light beam is generated and transmitted to the second spacecraft;

[0123] Step S55: When the second spacecraft receives the reflected light beam, the second side movable optical component of the second spacecraft is controlled to stop spatial scanning, and the reflected light beam is used to correct the adjustment direction of the second side movable optical component of the second spacecraft, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft.

[0124] Please note that Figure 4-Figure 5, using the guidance law coordinate system conversion method, the space capture of the bidirectional intersatellite laser link composed of the intersatellite laser link L3 (2-14) and the intersatellite laser link L3' (2-15) (i.e., the bidirectional intersatellite laser link between the second spacecraft and the first spacecraft) is carried out. Spacecraft No. 2-2 serves as the transmitting spacecraft, and actively adjusts the pointing direction of the second side movable optical component of the second spacecraft (i.e., the second side movable optical component pointing direction 4) in accordance with the guidance law in the uncertainty area in the yaw-pitch coordinate system of the second side movable optical component corresponding to the second spacecraft, i.e., the guidance law in the uncertainty area 12 in the yaw-pitch coordinate system of the second side movable optical component, and then performs a spatial scan of the uncertainty area 12 in the yaw-pitch coordinate system of the second side movable optical component (i.e., the uncertainty area corresponding to the first spacecraft). However, since the pointing adjustment components in the yaw direction 7 and the pitch direction 8 of the second side movable optical component cannot be directly controlled, it is necessary to It is necessary to first convert the guidance law formulated in the uncertainty area 12 in the yaw-pitch coordinate system of the second-side movable optical component into the guidance law in the uncertainty area 13 in the roll coordinate system of the second-side movable optical component - the bilateral pointing angle of the second-side movable optical component - around the first-side movable optical component (that is, the guidance law in the uncertainty area in the roll coordinate system of the second-side movable optical component corresponding to the second spacecraft - the bilateral pointing angle of the second-side movable optical component), wherein the pointing adjustment component in the bilateral pointing angle direction 10 is executed by the second-side movable optical component 2, and the pointing adjustment component in the roll direction 9 around the first-side movable optical component is executed by the spacecraft attitude control system to control the attitude of the spacecraft 14. At some point during this process, spacecraft 1 (2-1), acting as the receiving spacecraft, receives an outgoing beam from spacecraft 2-2. It then corrects the orientation of spacecraft 1's movable optical assembly 2-4 on its first side and sends a return beam back to spacecraft 2-2. After receiving the return beam, spacecraft 2-2 stops scanning and corrects the orientation of spacecraft 2's movable optical assembly 2-7 on its second side. This completes the space capture of the bidirectional intersatellite laser link consisting of intersatellite laser link L3 (2-14) and intersatellite laser link L3' (2-15). Figure 5 The spacecraft number in the presented space capture flow chart corresponds to this step.

[0125] In this embodiment, the transmitting spacecraft obtains the current installation matrix of the first-side and second-side movable optical components, calculates the required coordinate transformation matrix therefrom, and transforms the guidance law pre-established in the two-dimensional yaw-pitch coordinate system of the second-side movable optical component body coordinate system into the "bilateral pointing angle-roll around the pointing of the first-side movable optical component" coordinate system; the transmitting spacecraft performs space scanning according to the guidance law in the "bilateral pointing angle-roll around the pointing of the first-side movable optical component" coordinate system until the second-side capture sensor receives the reflected light beam; and subsequent steps such as the transmitting spacecraft pointing correction are executed.

[0126] Step 306: Based on the guidance law in the uncertainty region in the yaw-pitch coordinate system of the second side movable optical assembly corresponding to the first spacecraft, the pointing of the movable optical assemblies of the first spacecraft and the third spacecraft are adjusted to generate a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

[0127] Specifically, step 306 may include the following sub-steps S61-S65:

[0128] Step S61: Convert the guidance law in the uncertainty region of the yaw-pitch coordinate system of the second movable optical assembly corresponding to the first spacecraft to determine the guidance law in the uncertainty region of the roll coordinate system of the second movable optical assembly's bilateral pointing angle relative to the first movable optical assembly's pointing angle.

[0129] Step S62: Based on the guidance law in the uncertainty region in the roll coordinate system around the pointing of the second movable optical assembly on the first side of the first spacecraft, which is the included pointing angle between the two sides of the second movable optical assembly corresponding to the first spacecraft, the pointing of the second movable optical assembly on the first side of the first spacecraft is adjusted, the adjusted pointing of the second movable optical assembly on the first side of the first spacecraft is determined, and an outgoing light beam is generated.

[0130] Step S63: Based on the adjusted direction of the movable optical component on the second side of the first spacecraft, use the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the third spacecraft;

[0131] Step S64: When the third spacecraft receives the outgoing light beam, the outgoing light beam is used to correct the direction of the movable optical component on the first side of the third spacecraft, and a retroreflected light beam is generated and transmitted to the first spacecraft;

[0132] Step S65: When the first spacecraft receives the reflected light beam, the movable optical component on the second side of the first spacecraft is controlled to stop spatial scanning, and the adjusted direction of the movable optical component on the second side of the first spacecraft is corrected using the reflected light beam to generate a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

[0133] Please note that Figure 4, using the guidance law coordinate system conversion method, the space capture of the bidirectional intersatellite laser link composed of the intersatellite laser link L2 (2-12) and the intersatellite laser link L2' (2-13) is carried out (i.e., the bidirectional intersatellite laser link between the first spacecraft and the third spacecraft). Spacecraft No. 1 2-1 serves as the transmitting spacecraft, and actively adjusts the pointing direction 4 of the second side movable optical component (i.e., the pointing direction of the second side movable optical component of the first spacecraft) in accordance with the preset guidance law in the uncertainty area in the yaw-pitch coordinate system of the second side movable optical component corresponding to the first spacecraft, i.e., the guidance law in the uncertainty area 12 in the yaw-pitch coordinate system of the second side movable optical component. Then, the uncertainty area 12 in the yaw-pitch coordinate system of the second side movable optical component (i.e., the uncertainty area corresponding to the third spacecraft) is spatially scanned. However, since the pointing adjustment components in the yaw direction 7 and the pitch direction 8 of the second side movable optical component cannot be directly controlled It is necessary to first convert the guidance law formulated in the uncertainty region 12 in the yaw-pitch coordinate system of the second-side movable optical component into the guidance law in the uncertainty region 13 in the roll coordinate system of the second-side movable optical component bilateral pointing angle - around the first-side movable optical component (that is, the guidance law in the uncertainty region in the roll coordinate system of the second-side movable optical component bilateral pointing angle - around the first-side movable optical component corresponding to the second spacecraft), wherein the pointing adjustment component in the direction of the bilateral pointing angle 10 is executed by the second-side movable optical component 2, and the pointing adjustment component in the roll direction 9 around the first-side movable optical component is executed by the spacecraft attitude control system controlling the attitude of the spacecraft 14. At some point during this process, spacecraft 3 2-3, acting as the receiving spacecraft, receives the outgoing beam from spacecraft 1 2-1. It then corrects the orientation of spacecraft 3's first side movable optical assembly 2-8 and sends a return beam back to spacecraft 1 2-1. After receiving the return beam, spacecraft 1 2-1 stops its spatial scan and corrects the orientation of spacecraft 1's second side movable optical assembly 2-5. This completes the spatial capture of the bidirectional intersatellite laser link consisting of intersatellite laser link L2 (2-12) and intersatellite laser link L2' (2-13).

[0134] It is worth mentioning that the "guidance law" is a preset scanning trajectory for rotating the outgoing light beam to perform spatial scanning of the uncertain area. After completing the construction of multiple bidirectional intersatellite laser links, other subsequent processes are continued, such as fine pointing correction, device calibration and parameter estimation, etc. If there are no subsequent processes, the spatial capture of the three bidirectional intersatellite laser links of the triangular constellation is completed.

[0135] In an embodiment of the present invention, the method of guidance law coordinate system conversion is suitable for tasks in which the movable optical component is installed with sufficient precision or the installation matrix of the movable optical component can be accurately measured on-orbit, is insensitive to the time consumption cost and propellant consumption cost of the space scanning process, and is capable of designing an appropriate multi-controller collaborative pointing control scheme.

[0136] See also Figure 6 , Figure 6 This is a flowchart of the steps for performing space capture of an intersatellite laser link using a spacecraft attitude control system and a movable optical component iterative pointing adjustment method, provided in Example 3 of the present invention. The process may include the following steps:

[0137] Step 601: Based on the guidance law in the uncertainty area in the yaw-pitch coordinate system of the first-side movable optical component corresponding to the second spacecraft, adjust the direction of the first-side movable optical component of the second spacecraft, determine the adjusted direction of the first-side movable optical component of the second spacecraft, and generate an outgoing light beam corresponding to the first-side movable optical component of the second spacecraft.

[0138] Step 602: Based on the guidance law in the uncertainty area in the yaw-pitch coordinate system of the second side movable optical component corresponding to the second spacecraft, adjust the direction of the second side movable optical component of the second spacecraft, determine the adjusted direction of the second side movable optical component of the second spacecraft, and generate an outgoing light beam corresponding to the second side movable optical component of the second spacecraft.

[0139] Step 603: Based on the adjusted direction of the movable optical component on the first side of the second spacecraft, use the outgoing light beam corresponding to the movable optical component on the first side of the second spacecraft to perform spatial scanning on the uncertain area corresponding to the first spacecraft.

[0140] Step 604: Based on the adjusted direction of the second side movable optical component of the second spacecraft, use the outgoing light beam corresponding to the second side movable optical component of the second spacecraft to perform spatial scanning on the uncertain area corresponding to the third spacecraft.

[0141] Step 605: When the third spacecraft receives the outgoing light beam corresponding to the second side movable optical component of the second spacecraft, the outgoing light beam corresponding to the second side movable optical component of the second spacecraft is used to correct the direction of the second side movable optical component of the third spacecraft, and a return light beam corresponding to the second side movable optical component of the third spacecraft is generated and emitted to the second spacecraft.

[0142] Step 606: When the first spacecraft receives the outgoing light beam corresponding to the first side movable optical component of the second spacecraft, the outgoing light beam corresponding to the first side movable optical component of the second spacecraft is used to correct the direction of the first side movable optical component of the first spacecraft, and a return light beam corresponding to the first side movable optical component of the first spacecraft is generated and emitted to the second spacecraft.

[0143] Step 607: When the second spacecraft receives the reflected light beam corresponding to the second side movable optical component of the third spacecraft and the reflected light beam corresponding to the first side movable optical component of the first spacecraft, the first side movable optical component and the second side movable optical component of the second spacecraft are controlled to stop spatial scanning.

[0144] Step 608: Based on the reflected light beam corresponding to the second side movable optical component of the third spacecraft and the reflected light beam corresponding to the first side movable optical component of the first spacecraft, the spacecraft attitude control system and the first side movable optical component and the second side movable optical component of the second spacecraft are alternately used to iteratively correct the attitude of the second spacecraft, the adjustment direction of the first side movable optical component and the adjustment direction of the second side movable optical component to generate a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft and a bidirectional intersatellite laser link between the second spacecraft and the third spacecraft.

[0145] Please note that Figure 7-Figure 8, using the spacecraft attitude control system and the method of iteratively adjusting the pointing of the movable optical components, the bidirectional intersatellite laser link composed of the intersatellite laser link L1 (2-10) and the intersatellite laser link L1' (2-11) and the bidirectional intersatellite laser link composed of the intersatellite laser link L3 (2-14) and the intersatellite laser link L3' (2-15) are space captured. Spacecraft No. 2-2 serves as the transmitting spacecraft, and in accordance with the preset guidance law in the uncertainty area in the yaw-pitch coordinate system of the first side movable optical component corresponding to the second spacecraft and the guidance law in the uncertainty area in the yaw-pitch coordinate system of the second side movable optical component corresponding to the second spacecraft, that is, the guidance law in the uncertainty area 11 in the yaw-pitch coordinate system of the first side movable optical component and the guidance law in the uncertainty area 12 in the yaw-pitch coordinate system of the second side movable optical component, it actively adjusts the pointing direction 3 of the first side movable optical component (that is, the pointing direction of the first side movable optical component of the second spacecraft) and the pointing direction 4 of the second side movable optical component (that is, the pointing direction of the second side movable optical component of the second spacecraft) in sequence or simultaneously, and generates a corresponding outgoing light beam to the first side movable optical component. An uncertainty area 11 in the yaw-pitch coordinate system of the movable optical component on one side (i.e., the uncertainty area corresponding to the first spacecraft) and an uncertainty area 12 in the yaw-pitch coordinate system of the movable optical component on the second side (i.e., the uncertainty area corresponding to the third spacecraft) are spatially scanned, wherein the pointing adjustment component in the yaw direction 5 of the movable optical component on the first side is executed by the movable optical component on the first side 1, the pointing adjustment component in the pitch direction 6 of the movable optical component on the first side is executed by the attitude control system for controlling the attitude of the spacecraft 14, the pointing adjustment component in the yaw direction 7 of the movable optical component on the second side is executed by the movable optical component on the second side 2, and the pointing adjustment component in the pitch direction 8 of the movable optical component on the second side is executed by the attitude control system for controlling the attitude of the spacecraft 14. At a certain moment in this process, spacecraft No. 3 2-3 and spacecraft No. 1 2-1, which serve as receiving spacecraft, receive the outgoing light beam emitted by spacecraft No. 2 2-2, thereby correcting the pointing of the second side movable optical component 2-9 of spacecraft No. 3 and the pointing of the first side movable optical component 2-4 of spacecraft No. 1, and transmitting a return light beam to spacecraft No. 2 2-2. After receiving the return light beams on both sides, spacecraft No. 2 2-2 stops spatial scanning and begins to alternately use the spacecraft attitude control system and the two-sided movable optical components (i.e., the first side movable optical component and the second side movable optical component of the second spacecraft) to iteratively correct the attitude of spacecraft 14, the pointing 3 of the first side movable optical component, and the pointing 4 of the second side movable optical component (i.e., the attitude of the second spacecraft, the adjusted pointing of the first side movable optical component, and the adjusted pointing of the second side movable optical component). Each correction aims to minimize the incident angle error of the two-sided return light beams on the capture sensor, until the incident angle errors on both sides are simultaneously less than the preset tolerance, and the correction is completed.Thus, the space capture of the bidirectional intersatellite laser link consisting of the intersatellite laser link L1 (2-10) and the intersatellite laser link L1' (2-11), and the bidirectional intersatellite laser link consisting of the intersatellite laser link L3 (2-14) and the intersatellite laser link L3' (2-15) has been completed. Figure 8 The spacecraft number in the presented space capture flow chart corresponds to this step.

[0146] It is worth mentioning that when the capture sensor on one side of the transmitting spacecraft has received the return beam, the pointing correction on this side is not performed immediately, but the pointing correction is performed only after the capture sensors on both sides receive the return beam at the same time; at the same time, the space capture of the intersatellite laser link on both sides is not performed in the order of completing the space capture of the intersatellite laser link on one side first and then the space capture of the intersatellite laser link on the other side, but the space capture of the intersatellite laser link on both sides is completed simultaneously; in addition, the entire process of performing space scanning and correcting pointing does not use the spacecraft attitude control system and the movable optical component for coordinated pointing control, but uses the spacecraft attitude control system and the movable optical component alternately for pointing control, and preferably adopts guidance laws such as line scanning and rectangular scanning that adjust the pointing in only one direction at a time.

[0147] In this embodiment, S1, the transmitting spacecraft performs spatial scanning of the bilateral intersatellite laser links sequentially or simultaneously according to a pre-established guidance law until the bilateral capture sensors receive the reflected light beams; S2, the spacecraft attitude is adjusted with the goal of minimizing the incident angle errors of the bilateral return light beams on the capture sensors; S3, the movable optical components are adjusted with the goal of minimizing the incident angle errors of the bilateral return light beams on the capture sensors; S4, steps S2-3 are repeated until the incident angle errors of the bilateral return light beams on the capture sensors are both less than the preset tolerances.

[0148] Step 609: Based on the guidance law in the uncertainty area in the yaw-pitch coordinate system of the second-side movable optical component corresponding to the first spacecraft, adjust the direction of the second-side movable optical component of the first spacecraft, determine the adjusted direction of the second-side movable optical component of the first spacecraft, and generate an outgoing light beam corresponding to the second-side movable optical component of the first spacecraft.

[0149] Step 6010: Based on the adjusted direction of the movable optical component on the second side of the first spacecraft, use the outgoing light beam corresponding to the movable optical component on the second side of the first spacecraft to perform spatial scanning on the uncertain area corresponding to the third spacecraft.

[0150] Step 6011: When the third spacecraft receives the outgoing light beam corresponding to the second-side movable optical component of the first spacecraft, the spacecraft attitude control system and the first-side movable optical component and the second-side movable optical component of the third spacecraft are alternately used to iteratively correct the attitude of the third spacecraft, the adjustment direction of the first-side movable optical component, and the adjustment direction of the second-side movable optical component, and generate a return light beam corresponding to the first-side movable optical component and the second-side movable optical component of the third spacecraft to transmit to the first spacecraft.

[0151] Step 6012: When the first spacecraft receives the return light beam corresponding to the first side movable optical component and the second side movable optical component of the third spacecraft, the second side movable optical component of the first spacecraft is controlled to stop spatial scanning.

[0152] Step 6013: Based on the reflected light beam corresponding to the first side movable optical component and the reflected light beam corresponding to the second side movable optical component of the third spacecraft, alternately use the spacecraft attitude control system and the first side movable optical component and the second side movable optical component of the first spacecraft to iteratively correct the attitude of the first spacecraft, the direction of the first side movable optical component, and the adjusted direction of the second side movable optical component, and generate a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

[0153] Please note that Figure 7, using the spacecraft attitude control system and the method of iteratively adjusting the pointing of the movable optical components, the space capture of the bidirectional intersatellite laser link consisting of the intersatellite laser link L2 (2-12) and the intersatellite laser link L2' (2-13) was carried out. Spacecraft No. 1 2-1 serves as the transmitting spacecraft. At this time, the intersatellite laser link L3 (2-14) has been established, which is equivalent to the return beam from spacecraft No. 2 2-2. At this time, spacecraft No. 1 2-1 skips the spatial scanning of the uncertainty region 11 in the yaw-pitch coordinate system of the first side movable optical component, and directly adjusts the pointing direction 4 of the second side movable optical component (the pointing direction of the second side movable optical component of the first spacecraft) according to the guidance law in the uncertainty region in the yaw-pitch coordinate system of the second side movable optical component corresponding to the first spacecraft, and performs a spatial scan of the uncertainty region 12 in the yaw-pitch coordinate system of the second side movable optical component (the uncertainty region corresponding to the third spacecraft). The pointing adjustment component of the second side movable optical component in the yaw direction 7 is performed by the second side movable optical component 2, and the pointing adjustment component in the pitch direction 8 of the second side movable optical component is performed by the spacecraft attitude control system controlling the attitude of the spacecraft 14. At some point during this process, spacecraft 3 2-3, acting as the receiving spacecraft, receives an outgoing beam from spacecraft 1 2-1. It then uses the spacecraft attitude control system and the movable optical assembly to iteratively adjust its orientation, alternating between the spacecraft attitude control system and the two-sided movable optical assembly to iteratively correct its spacecraft attitude and the orientation of the two-sided movable optical assembly. After the correction is complete, it transmits a return beam to spacecraft 1 2-1. After receiving the two-sided return beams, spacecraft 1 2-1 ceases its spatial scanning and begins iteratively adjusting its orientation and the orientation of the two-sided movable optical assembly, alternating between the spacecraft attitude control system and the two-sided movable optical assembly until the correction is complete. This completes the spatial capture of the bidirectional intersatellite laser link consisting of intersatellite laser link L2 (2-12) and intersatellite laser link L2' (2-13).

[0154] It is worth mentioning that after completing the construction of multiple bidirectional intersatellite laser links, other subsequent processes are executed, such as fine pointing correction, device calibration and calibration, parameter estimation, etc. If there are no subsequent processes, the spatial capture of the three bidirectional intersatellite laser links in the triangle constellation is completed.

[0155] In an embodiment of the present invention, the spacecraft attitude control system and the method for iteratively adjusting the pointing of the movable optical component are suitable for tasks with high reliability requirements, low precision of the movable optical component installation matrix, and simple constellation inter-satellite laser link structure.

[0156] See also Figure 9 , Figure 9A flowchart of the steps for performing intersatellite laser link acquisition using the one-sided intersatellite laser link space acquisition method and the pointing degree of freedom constraint method provided in the fourth embodiment of the present invention. The process may include the following steps:

[0157] Step 901: Based on the guidance law in the uncertainty area in the yaw-pitch coordinate system of the first side movable optical component corresponding to the second spacecraft, adjust the direction of the first side movable optical component of the second spacecraft, determine the adjusted direction of the first side movable optical component of the second spacecraft, and generate an outgoing light beam.

[0158] Step 902: Based on the adjusted direction of the movable optical component on the first side of the second spacecraft, use the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the third spacecraft.

[0159] Step 903: When the third spacecraft receives the outgoing light beam, the direction of the movable optical component on the second side of the third spacecraft is corrected based on the outgoing light beam, and a retroreflected light beam is generated and transmitted to the second spacecraft.

[0160] Step 904: When the second spacecraft receives the reflected light beam, the movable optical component on the first side of the second spacecraft is controlled to stop spatial scanning, and the adjusted direction of the movable optical component on the first side of the second spacecraft is corrected using the reflected light beam to generate a bidirectional intersatellite laser link between the second spacecraft and the third spacecraft.

[0161] Please note that Figure 10Using a conventional single-sided intersatellite laser link spatial capture method, a bidirectional intersatellite laser link consisting of intersatellite laser link L1 (2-10) and intersatellite laser link L1' (2-11) is spatially captured. Spacecraft 2-2 serves as the transmitting spacecraft and actively adjusts the orientation 3 of the first movable optical assembly (the orientation of the first movable optical assembly of the second spacecraft) in accordance with a preset guidance law for the uncertainty region in the yaw-pitch coordinate system of the first movable optical assembly corresponding to the second spacecraft (i.e., the guidance law for the uncertainty region 11 in the yaw-pitch coordinate system of the first movable optical assembly). The spacecraft performs a spatial scan of uncertainty region 11 in the yaw-pitch coordinate system of the first movable optical assembly (i.e., the uncertainty region corresponding to the third spacecraft). The orientation adjustment component of the first movable optical assembly in the yaw direction 5 is performed by the first movable optical assembly 1, while the orientation adjustment component in the pitch direction 6 of the first movable optical assembly is performed by the spacecraft attitude control system controlling the attitude of the spacecraft 14. At some point during this process, spacecraft 3 2-3, acting as the receiving spacecraft, receives the outgoing beam from spacecraft 2 2-2. It then corrects the pointing direction of spacecraft 3's second-side movable optical assembly 2-9 and sends a return beam back to spacecraft 2 2-2. After receiving the return beam, spacecraft 2 2-2 stops its spatial scanning and corrects the pointing direction of spacecraft 2's first-side movable optical assembly 2-6. This completes the spatial capture of the bidirectional intersatellite laser link consisting of intersatellite laser link L1 (2-10) and intersatellite laser link L1' (2-11).

[0162] Step 905: Determine the pointing error of the second side movable optical assembly of the second spacecraft based on the corrected actual direction of the outgoing light beam emitted by the first side movable optical assembly of the second spacecraft.

[0163] Step 906: Determine the guidance law in the uncertainty region in the roll coordinate system around the pointing angle of the second side movable optical component of the second spacecraft according to the pointing error of the second side movable optical component of the second spacecraft.

[0164] Step 907: Based on the guidance law in the uncertain area in the rolling coordinate system around the pointing of the movable optical component on the first side of the second spacecraft, which is the bilateral pointing angle of the movable optical component on the second side of the second spacecraft, the pointing of the movable optical component on the second side of the second spacecraft is adjusted, the adjusted pointing of the movable optical component on the second side of the second spacecraft is determined, and an outgoing light beam is generated.

[0165] Step 908: Based on the adjusted direction of the movable optical component on the second side of the second spacecraft, use the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the first spacecraft.

[0166] When the first spacecraft receives the outgoing light beam, the orientation of the first side movable optical component of the first spacecraft is corrected based on the outgoing light beam, and a retroreflected light beam is generated and transmitted to the second spacecraft.

[0167] Step 909: When the second spacecraft receives the reflected light beam, the second side movable optical component of the second spacecraft is controlled to stop space scanning, and the reflected light beam is used to correct the adjustment direction of the second side movable optical component of the second spacecraft to generate a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft.

[0168] Please note that Figure 10-11 Using a method that constrains the pointing degrees of freedom one by one, a bidirectional intersatellite laser link consisting of intersatellite laser link L3 (2-14) and intersatellite laser link L3' (2-15) is spatially captured. Spacecraft 2-2, acting as the transmitting spacecraft, estimates the pointing error of the second-side movable optical assembly 4 in the direction of the bilateral pointing angle 10 and the roll direction 9 about the pointing direction of the first-side movable optical assembly. This is the pointing error of the second-side movable optical assembly of the second spacecraft. The pointing error of the "second-side" movable optical assembly of spacecraft 2 is estimated based on the actual direction of the "first-side" outgoing light beam emitted by the "first-side" movable optical assembly of spacecraft 2, after the pointing error has been fully corrected.

[0169] Next, the uncertainty region 13 in the rolling coordinate system around the pointing direction of the movable optical component on the first side and the included angle of the two sides pointing of the movable optical component on the second side is calculated, and the guidance law is formulated based on this as the boundary (i.e., the guidance law in the uncertainty region in the rolling coordinate system around the pointing direction of the movable optical component on the first side and the included angle of the two sides pointing of the movable optical component on the second side corresponding to the second spacecraft). Only the uncertainty region 13 in the rolling coordinate system around the pointing direction of the movable optical component on the first side and the included angle of the two sides pointing of the movable optical component on the second side (i.e., the uncertainty region corresponding to the first spacecraft) is spatially scanned. Among them, the measurement and control accuracy of the absolute attitude of the spacecraft 14 in the inertial system when entering orbit is low, and the absolute angle measurement and control accuracy of the first-side movable optical component 1 and the second-side movable optical component 2 is high. Therefore, the uncertainty area component in the bilateral pointing angle direction 10 is small, and the uncertainty area component in the roll direction 9 pointing around the first-side movable optical component is large. Moreover, the uncertainty area 13 in the roll coordinate system of the bilateral pointing angle of the second-side movable optical component - around the first-side movable optical component is smaller in both directions than the uncertainty area 11 in the yaw-pitch coordinate system of the first-side movable optical component.

[0170] Furthermore, at some point during this process, spacecraft 1 2-1, acting as the receiving spacecraft, receives an outgoing beam from spacecraft 2 2-2, thereby correcting the pointing direction of spacecraft 1's first side movable optical assembly 2-4 and transmitting a return beam to spacecraft 2 2-2. Upon receiving the return beam, spacecraft 2 2-2 ceases its spatial scanning and corrects the pointing direction of spacecraft 2's second side movable optical assembly 2-7. This completes the spatial capture of the bidirectional intersatellite laser link consisting of intersatellite laser link L3 (2-14) and intersatellite laser link L3' (2-15). Figure 11 The spacecraft number in the presented space capture flow chart corresponds to this step.

[0171] In this embodiment, the remaining parameter space of the remaining under-constrained pointing degrees of freedom is estimated, a new uncertainty region is determined in the remaining parameter space, and a guidance law is formulated with the new uncertainty region as the boundary; the transmitting spacecraft performs spatial scanning according to the guidance law formulated in the remaining parameter space until the second-side capture sensor receives the reflected light beam; and subsequent steps such as transmitting spacecraft pointing correction are executed.

[0172] Step 9010: Determine the pointing error of the movable optical assembly on the second side of the first spacecraft based on the corrected actual direction of the outgoing light beam emitted by the movable optical assembly on the first side of the first spacecraft.

[0173] Step 9011: Determine the guidance law in the uncertain area in the rolling coordinate system around the pointing error of the second side movable optical component of the first spacecraft, i.e., the bilateral pointing angle of the second side movable optical component corresponding to the first spacecraft.

[0174] Step 9012: Based on the guidance law in the uncertain area in the rolling coordinate system around the pointing of the movable optical component on the second side of the first spacecraft, which is the bilateral pointing angle of the movable optical component on the second side corresponding to the first spacecraft, the pointing of the movable optical component on the second side of the first spacecraft is adjusted, the adjusted pointing of the movable optical component on the second side of the first spacecraft is determined, and an outgoing light beam is generated.

[0175] Step 9013: Based on the adjusted direction of the movable optical component on the second side of the first spacecraft, use the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the third spacecraft.

[0176] Step 9014: When the third spacecraft receives the outgoing light beam, the direction of the movable optical component on the first side of the third spacecraft is corrected based on the outgoing light beam, and a return light beam is generated and transmitted to the first spacecraft.

[0177] Step 9015: When the first spacecraft receives the reflected light beam, the movable optical component on the second side of the first spacecraft is controlled to stop space scanning, and the reflected light beam is used to correct the adjustment direction of the movable optical component on the second side of the first spacecraft, thereby generating a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

[0178] Please note that Figure 10 Using a method that constrains the pointing degrees of freedom one by one, a spatial capture of the bidirectional intersatellite laser link consisting of intersatellite laser link L2 (2-12) and intersatellite laser link L2' (2-13) is performed. Spacecraft 1, acting as the transmitting spacecraft, 2-1, estimates the pointing error of the second movable optical assembly 4 in the direction of the bilateral pointing angle 10 and the roll direction 9 about the pointing of the first movable optical assembly, i.e., the pointing error of the second movable optical assembly of the first spacecraft. Based on this, an uncertainty region 13 in the roll coordinate system (the difference between the bilateral pointing angle of the second movable optical assembly and the pointing of the first movable optical assembly) is calculated. This uncertainty region 13 is then used as the boundary for formulating a guidance law within the uncertainty region of the second movable optical assembly's bilateral pointing angle and the pointing of the first movable optical assembly in the roll coordinate system for the first spacecraft. Spatial scanning is performed only within the uncertainty region 13 in the roll coordinate system (the difference between the bilateral pointing angle of the second movable optical assembly and the pointing of the first movable optical assembly) (i.e., the uncertainty region corresponding to the third spacecraft). Among them, the measurement and control accuracy of the absolute attitude of the spacecraft 14 in the inertial system when entering orbit is low, and the absolute angle measurement and control accuracy of the first side movable optical component 1 and the second side movable optical component 2 is high. Therefore, the uncertainty area component in the bilateral pointing angle direction 10 is small, and the uncertainty area component in the roll direction 9 around the first side movable optical component is large. Moreover, the uncertainty area 13 in the roll coordinate system of the bilateral pointing angle of the second side movable optical component - around the first side movable optical component is smaller in both directions than the uncertainty area 11 in the yaw-pitch coordinate system of the first side movable optical component.

[0179] At some point during this process, spacecraft 3 2-3, acting as the receiving spacecraft, receives the outgoing beam from spacecraft 1 2-1. It then corrects the orientation of spacecraft 3's first side movable optical assembly 2-8 and sends a return beam back to spacecraft 1 2-1. After receiving the return beam, spacecraft 1 2-1 stops its spatial scanning and corrects the orientation of spacecraft 1's second side movable optical assembly 2-5. This completes the spatial capture of the bidirectional intersatellite laser link consisting of intersatellite laser link L2 (2-12) and intersatellite laser link L2' (2-13).

[0180] It is worth mentioning that after completing the construction of multiple bidirectional intersatellite laser links, other subsequent processes are executed, such as fine pointing correction, device calibration and calibration, parameter estimation, etc. If there are no subsequent processes, the spatial capture of the three bidirectional intersatellite laser links in the triangle constellation is completed.

[0181] In an embodiment of the present invention, the method of constraining the pointing degrees of freedom one by one has the lowest time consumption cost and propellant consumption cost, can avoid spatial scanning of invalid areas, and minimize the number of scanning points used in the spatial scanning process. It is suitable for tasks that are sensitive to the time consumption cost and propellant consumption cost of the capture process.

[0182] See also Figure 12 , Figure 12 This is a structural block diagram of a spacecraft dual-side intersatellite laser link space capture system provided in Example 5 of the present invention.

[0183] The present invention provides a structural block diagram of a spacecraft dual-side intersatellite laser link space capture system, including:

[0184] The acquisition module 1201 is used to acquire key indicator data of the capture task and determine whether the key indicator data of the capture task meets the preset first capture condition, the preset second capture condition or the preset third capture condition;

[0185] The first capture module 1202 is configured to, when the key indicator data of the capture mission meets a preset first capture condition, perform intersatellite laser link capture on the spacecraft group using a unilateral intersatellite laser link space capture method and a guidance law coordinate system conversion method to generate multiple bidirectional intersatellite laser links;

[0186] The second capture module 1203 is configured to, when the key indicator data of the capture mission meets the preset second capture condition, perform intersatellite laser link capture on the spacecraft group using the spacecraft attitude control system and the movable optical component iterative pointing adjustment method to generate multiple bidirectional intersatellite laser links;

[0187] The third capture module 1204 is used to capture the spacecraft group's intersatellite laser link using a unilateral intersatellite laser link space capture method and a pointing degree of freedom constraint method when the key indicator data of the capture mission meets the preset third capture condition, generating multiple bidirectional intersatellite laser links.

[0188] Furthermore, the spacecraft group includes a first spacecraft, a second spacecraft, and a third spacecraft; the first capture module 1202 includes:

[0189] a first submodule, configured to adjust the orientation of the first movable optical assembly on the second spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the first movable optical assembly on the second spacecraft, determine the adjusted orientation of the first movable optical assembly on the second spacecraft, and generate an outgoing light beam;

[0190] The second submodule is configured to perform spatial scanning of the uncertain area corresponding to the third spacecraft using an outgoing light beam based on the adjusted pointing direction of the movable optical component on the first side of the second spacecraft;

[0191] a third submodule, configured to, when the third spacecraft receives the outgoing light beam, correct the orientation of the movable optical assembly on the second side of the third spacecraft based on the outgoing light beam, and generate a retroreflected light beam to be transmitted to the second spacecraft;

[0192] a fourth submodule, configured to control the movable optical assembly on the first side of the second spacecraft to stop spatial scanning when the second spacecraft receives the retroreflected light beam, and to use the retroreflected light beam to correct the adjustment direction of the movable optical assembly on the first side of the second spacecraft, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the third spacecraft;

[0193] a fifth submodule, configured to adjust the pointing direction of the movable optical components of the second spacecraft and the first spacecraft based on the guidance law in the uncertainty region of the yaw-pitch coordinate system of the second side movable optical component corresponding to the second spacecraft, and generate a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft;

[0194] The sixth submodule is used to adjust the pointing of the movable optical components of the first spacecraft and the third spacecraft based on the guidance law in the uncertainty area in the yaw-pitch coordinate system of the second side movable optical component corresponding to the first spacecraft, and generate a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

[0195] Furthermore, the fifth submodule is specifically configured to:

[0196] Converting the guidance law in the uncertainty region of the yaw-pitch coordinate system of the second movable optical assembly corresponding to the second spacecraft to determine the guidance law in the uncertainty region of the roll coordinate system of the bilateral pointing angle of the second movable optical assembly corresponding to the second spacecraft about the pointing angle of the first movable optical assembly;

[0197] Adjusting the orientation of the second movable optical assembly on the second side of the second spacecraft based on the guidance law in the uncertainty region in the roll coordinate system around the orientation of the first movable optical assembly, based on the bilateral orientation angle of the second movable optical assembly corresponding to the second spacecraft, determines the adjusted orientation of the second movable optical assembly on the second side of the second spacecraft, and generates an outgoing light beam;

[0198] Based on the adjusted direction of the movable optical component on the second side of the second spacecraft, the outgoing light beam is used to perform spatial scanning on the uncertain area corresponding to the first spacecraft;

[0199] When the first spacecraft receives the outgoing light beam, the outgoing light beam is used to correct the orientation of the movable optical assembly on the first side of the first spacecraft, and a retroreflected light beam is generated and transmitted to the second spacecraft;

[0200] When the second spacecraft receives the reflected light beam, the second side movable optical component of the second spacecraft is controlled to stop space scanning, and the reflected light beam is used to correct the adjustment direction of the second side movable optical component of the second spacecraft, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft.

[0201] Furthermore, the sixth submodule is specifically configured to:

[0202] Converting the guidance law in the uncertainty region of the yaw-pitch coordinate system of the second movable optical assembly corresponding to the first spacecraft to determine the guidance law in the uncertainty region of the roll coordinate system of the bilateral pointing angle of the second movable optical assembly corresponding to the first spacecraft and around the pointing angle of the first movable optical assembly;

[0203] Adjusting the orientation of the second movable optical assembly of the first spacecraft based on the guidance law in the uncertainty region in the roll coordinate system around the orientation of the first movable optical assembly, which is the bilateral orientation angle of the second movable optical assembly corresponding to the first spacecraft, determines the adjusted orientation of the second movable optical assembly of the first spacecraft, and generates an outgoing light beam;

[0204] Based on the adjusted direction of the movable optical component on the second side of the first spacecraft, the outgoing light beam is used to perform spatial scanning on the uncertain area corresponding to the third spacecraft;

[0205] When the third spacecraft receives the outgoing light beam, the outgoing light beam is used to correct the orientation of the movable optical component on the first side of the third spacecraft, and a retroreflected light beam is generated and transmitted to the first spacecraft;

[0206] When the first spacecraft receives the return beam, the second side movable optical component of the first spacecraft is controlled to stop spatial scanning, and the adjustment direction of the second side movable optical component of the first spacecraft is corrected using the return beam to generate a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

[0207] Furthermore, the second capturing module 1203 is specifically configured to:

[0208] adjusting the orientation of the first movable optical assembly on the second spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the first movable optical assembly on the second spacecraft, determining the adjusted orientation of the first movable optical assembly on the second spacecraft, and generating an outgoing light beam corresponding to the first movable optical assembly on the second spacecraft;

[0209] adjusting the orientation of the second side movable optical assembly of the second spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the second side movable optical assembly corresponding to the second spacecraft, determining the adjusted orientation of the second side movable optical assembly of the second spacecraft, and generating an outgoing light beam corresponding to the second side movable optical assembly of the second spacecraft;

[0210] Based on the adjusted direction of the movable optical component on the first side of the second spacecraft, using the outgoing light beam corresponding to the movable optical component on the first side of the second spacecraft to perform spatial scanning on the uncertain area corresponding to the first spacecraft;

[0211] Based on the adjusted direction of the second side movable optical component of the second spacecraft, using the outgoing light beam corresponding to the second side movable optical component of the second spacecraft to perform spatial scanning on the uncertain area corresponding to the third spacecraft;

[0212] When the third spacecraft receives the outgoing light beam corresponding to the second side movable optical assembly of the second spacecraft, the third spacecraft uses the outgoing light beam corresponding to the second side movable optical assembly of the second spacecraft to correct the direction of the second side movable optical assembly of the third spacecraft, and generates a return light beam corresponding to the second side movable optical assembly of the third spacecraft and transmits it to the second spacecraft;

[0213] When the first spacecraft receives an outgoing light beam corresponding to the first side movable optical assembly of the second spacecraft, the first spacecraft uses the outgoing light beam corresponding to the first side movable optical assembly of the second spacecraft to correct the direction of the first side movable optical assembly of the first spacecraft, and generates a retroreflected light beam corresponding to the first side movable optical assembly of the first spacecraft and transmits it to the second spacecraft;

[0214] When the second spacecraft receives the retroreflected light beam corresponding to the second side movable optical assembly of the third spacecraft and the retroreflected light beam corresponding to the first side movable optical assembly of the first spacecraft, controlling the first side movable optical assembly and the second side movable optical assembly of the second spacecraft to stop spatial scanning;

[0215] Based on the retroreflected light beam corresponding to the second side movable optical assembly of the third spacecraft and the retroreflected light beam corresponding to the first side movable optical assembly of the first spacecraft, the spacecraft attitude control system and the first side movable optical assembly and the second side movable optical assembly of the second spacecraft are alternately used to iteratively correct the attitude of the second spacecraft, the adjusted orientation of the first side movable optical assembly, and the adjusted orientation of the second side movable optical assembly, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft, and a bidirectional intersatellite laser link between the second spacecraft and the third spacecraft;

[0216] adjusting the orientation of the second movable optical assembly on the first spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the second movable optical assembly corresponding to the first spacecraft, determining the adjusted orientation of the second movable optical assembly on the first spacecraft, and generating an outgoing light beam corresponding to the second movable optical assembly on the first spacecraft;

[0217] Based on the adjusted direction of the movable optical component on the second side of the first spacecraft, using the outgoing light beam corresponding to the movable optical component on the second side of the first spacecraft to perform spatial scanning on the uncertain area corresponding to the third spacecraft;

[0218] When the third spacecraft receives the outgoing light beam corresponding to the second side movable optical assembly of the first spacecraft, the spacecraft attitude control system and the first side movable optical assembly and the second side movable optical assembly of the third spacecraft are alternately used to iteratively correct the attitude of the third spacecraft, the adjustment direction of the first side movable optical assembly, and the adjustment direction of the second side movable optical assembly, and a retroreflected light beam corresponding to the first side movable optical assembly and the retroreflected light beam corresponding to the second side movable optical assembly of the third spacecraft are generated and transmitted to the first spacecraft;

[0219] When the first spacecraft receives the retroreflected light beam corresponding to the first side movable optical component and the retroreflected light beam corresponding to the second side movable optical component of the third spacecraft, controlling the second side movable optical component of the first spacecraft to stop spatial scanning;

[0220] Based on the retroreflected light beam corresponding to the first side movable optical component and the retroreflected light beam corresponding to the second side movable optical component of the third spacecraft, the spacecraft attitude control system and the first side movable optical component and the second side movable optical component of the first spacecraft are alternately used to iteratively correct the attitude of the first spacecraft, the direction of the first side movable optical component, and the adjusted direction of the second side movable optical component, and generate a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

[0221] Furthermore, the third capturing module 1204 is specifically configured to:

[0222] adjusting the orientation of the first movable optical assembly on the second spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the first movable optical assembly corresponding to the second spacecraft, determining the adjusted orientation of the first movable optical assembly on the second spacecraft, and generating an outgoing light beam;

[0223] Based on the adjusted pointing direction of the movable optical component on the first side of the second spacecraft, the outgoing light beam is used to perform spatial scanning on the uncertain area corresponding to the third spacecraft;

[0224] When the third spacecraft receives the outgoing light beam, the third spacecraft corrects the orientation of the second side movable optical assembly of the third spacecraft based on the outgoing light beam, and generates a retroreflected light beam to be transmitted to the second spacecraft;

[0225] When the second spacecraft receives the retroreflected light beam, the movable optical assembly on the first side of the second spacecraft is controlled to stop spatial scanning, and the adjustment direction of the movable optical assembly on the first side of the second spacecraft is corrected using the retroreflected light beam, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the third spacecraft;

[0226] determining a pointing error of the second side movable optical assembly of the second spacecraft based on the corrected actual direction of the outgoing light beam emitted by the first side movable optical assembly of the second spacecraft;

[0227] Determining, based on the pointing error of the second side movable optical assembly of the second spacecraft, a guidance law for the second spacecraft's corresponding second side movable optical assembly bilateral pointing angle in an uncertainty region in the roll coordinate system around the pointing of the first side movable optical assembly;

[0228] Adjusting the orientation of the second movable optical assembly on the second side of the second spacecraft based on a guidance law in an uncertainty region in a roll coordinate system around the orientation of the movable optical assembly on the first side of the second spacecraft based on the bilateral orientation angle of the second movable optical assembly corresponding to the second spacecraft, determining the adjusted orientation of the second movable optical assembly on the second side of the second spacecraft, and generating an outgoing light beam;

[0229] Based on the adjusted direction of the movable optical component on the second side of the second spacecraft, the outgoing light beam is used to perform spatial scanning on the uncertain area corresponding to the first spacecraft;

[0230] When the first spacecraft receives the outgoing light beam, the first spacecraft corrects the orientation of the movable optical assembly on the first side based on the outgoing light beam, and generates a retroreflected light beam to be transmitted to the second spacecraft;

[0231] When the second spacecraft receives the retroreflected light beam, the second side movable optical assembly of the second spacecraft is controlled to stop spatial scanning, and the adjustment direction of the second side movable optical assembly of the second spacecraft is corrected using the retroreflected light beam, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft;

[0232] determining a pointing error of a second side movable optical assembly of the first spacecraft based on the corrected actual direction of the outgoing light beam emitted by the first side movable optical assembly of the first spacecraft;

[0233] Determining, based on the pointing error of the second side movable optical assembly of the first spacecraft, a guidance law for the first spacecraft in an uncertainty region in a roll coordinate system around the pointing angle of the second side movable optical assembly corresponding to the first spacecraft;

[0234] Adjusting the orientation of the second movable optical assembly on the first spacecraft based on the guidance law in the uncertainty region in the roll coordinate system around the orientation of the first movable optical assembly on the second side of the first spacecraft based on the bilateral orientation angle of the second movable optical assembly corresponding to the first spacecraft, determining the adjusted orientation of the second movable optical assembly on the first spacecraft, and generating an outgoing light beam;

[0235] Based on the adjusted direction of the movable optical component on the second side of the first spacecraft, the outgoing light beam is used to perform spatial scanning on the uncertain area corresponding to the third spacecraft;

[0236] When the third spacecraft receives the outgoing light beam, the third spacecraft corrects the orientation of the movable optical component on the first side of the third spacecraft based on the outgoing light beam, and generates a retroreflected light beam to be transmitted to the first spacecraft;

[0237] When the first spacecraft receives the return beam, the second side movable optical component of the first spacecraft is controlled to stop spatial scanning, and the adjustment direction of the second side movable optical component of the first spacecraft is corrected using the return beam to generate a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

[0238] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described systems, modules and sub-modules can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0239] An embodiment of the present invention also provides a computer device, including a memory and a processor, wherein a computer program is stored in the memory; when the computer program is executed by the processor, the processor executes the steps of the space capture method of the spacecraft bilateral inter-satellite laser link as described in any of the above embodiments.

[0240] An embodiment of the present invention further provides a computer-readable storage medium having a computer program / instruction stored thereon. When the computer program / instruction is executed by a processor, the steps of the space capture method of a spacecraft bilateral inter-satellite laser link are implemented as described in any of the above embodiments.

[0241] An embodiment of the present invention further provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements the steps of the space capture method of a spacecraft bilateral inter-satellite laser link as described in any of the above embodiments.

[0242] In the several embodiments provided in this application, it should be understood that the disclosed systems and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0243] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0244] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features thereof can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A spacecraft bilateral intersatellite laser link space capture method, characterized in that: Applied to a spacecraft assembly, the method comprises: Acquiring key indicator data of a capture task, and determining whether the key indicator data of the capture task satisfies a preset first capture condition, a preset second capture condition, or a preset third capture condition; When the capture mission key indicator data meets the preset first capture condition, performing intersatellite laser link capture on the spacecraft group using a unilateral intersatellite laser link space capture method and a guidance law coordinate system conversion method to generate multiple bidirectional intersatellite laser links; When the capture mission key indicator data satisfies the preset second capture condition, performing intersatellite laser link capture on the spacecraft group using a spacecraft attitude control system and a movable optical component iterative pointing adjustment method to generate multiple bidirectional intersatellite laser links; When the key indicator data of the capture mission meets the preset third capture condition, the spacecraft group is captured using the unilateral intersatellite laser link space capture method and the pointing degree of freedom constraint method to generate multiple bidirectional intersatellite laser links.

2. The space capture method for a spacecraft bilateral intersatellite laser link according to claim 1, characterized in that: The spacecraft group includes a first spacecraft, a second spacecraft, and a third spacecraft; the guidance law includes a first guidance law; and the method of using a unilateral intersatellite laser link space capture method and a guidance law coordinate system conversion method to perform intersatellite laser link capture on multiple spacecraft to generate multiple bidirectional intersatellite laser links includes: adjusting the orientation of the first side movable optical assembly of the second spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the first side movable optical assembly corresponding to the second spacecraft, determining the adjusted orientation of the first side movable optical assembly of the second spacecraft, and generating an outgoing light beam; Based on the adjusted direction of the movable optical component on the first side of the second spacecraft, using the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the third spacecraft; When the third spacecraft receives the outgoing light beam, the third spacecraft corrects the orientation of the second side movable optical component of the third spacecraft based on the outgoing light beam, and generates a retroreflected light beam to be transmitted to the second spacecraft; When the second spacecraft receives the retroreflected light beam, the movable optical assembly on the first side of the second spacecraft is controlled to stop spatial scanning, and the adjustment direction of the movable optical assembly on the first side of the second spacecraft is corrected using the retroreflected light beam, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the third spacecraft; performing, based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of a second side movable optical assembly corresponding to the second spacecraft, pointing adjustments of the movable optical assemblies of the second spacecraft and the first spacecraft, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft; Based on the guidance law in the uncertainty area of ​​the yaw-pitch coordinate system of the second side movable optical component corresponding to the first spacecraft, the pointing of the movable optical components of the first spacecraft and the third spacecraft are adjusted to generate a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

3. The space capture method for spacecraft bilateral intersatellite laser links according to claim 2, characterized in that: The method of adjusting the pointing direction of the movable optical components of the second spacecraft and the first spacecraft based on the guidance law in the uncertainty region in the yaw-pitch coordinate system of the second side movable optical component corresponding to the second spacecraft to generate a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft includes: converting the guidance law in the uncertainty region of the yaw-pitch coordinate system of the second movable optical assembly corresponding to the second spacecraft to determine the guidance law in the uncertainty region of the roll coordinate system of the bilateral pointing angle of the second movable optical assembly corresponding to the second spacecraft about the pointing angle of the first movable optical assembly; adjusting the orientation of the second movable optical assembly on the second side of the second spacecraft based on a guidance law in an uncertainty region in a roll coordinate system around the orientation of the movable optical assembly on the first side of the second spacecraft, determining the adjusted orientation of the second movable optical assembly on the second side of the second spacecraft, and generating an outgoing light beam; Based on the adjusted direction of the movable optical component on the second side of the second spacecraft, using the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the first spacecraft; When the first spacecraft receives the outgoing light beam, the first spacecraft uses the outgoing light beam to correct the direction of the movable optical component on the first side of the first spacecraft, and generates a retroreflected light beam to be transmitted to the second spacecraft; When the second spacecraft receives the reflected light beam, the second side movable optical component of the second spacecraft is controlled to stop spatial scanning, and the reflected light beam is used to correct the adjustment direction of the second side movable optical component of the second spacecraft, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft.

4. The space capture method for spacecraft bilateral intersatellite laser links according to claim 2, characterized in that: The method of adjusting the pointing direction of the movable optical components of the first spacecraft and the third spacecraft based on the guidance law in the uncertainty region in the yaw-pitch coordinate system of the second side movable optical component corresponding to the first spacecraft, and generating a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft includes: converting a guidance law in an uncertainty region in a yaw-pitch coordinate system of the second movable optical assembly corresponding to the first spacecraft to determine a guidance law in an uncertainty region in a roll coordinate system of a bilateral pointing angle of the second movable optical assembly corresponding to the first spacecraft and around the pointing angle of the first movable optical assembly; Adjusting the orientation of the second movable optical assembly on the first spacecraft based on a guidance law in an uncertainty region in a roll coordinate system around the orientation of the first movable optical assembly on the second side of the first spacecraft based on the included angle of the two-side orientation of the second movable optical assembly corresponding to the first spacecraft, determining the adjusted orientation of the second movable optical assembly on the first spacecraft, and generating an outgoing light beam; Based on the adjusted direction of the movable optical component on the second side of the first spacecraft, using the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the third spacecraft; When the third spacecraft receives the outgoing light beam, the outgoing light beam is used to correct the direction of the movable optical component on the first side of the third spacecraft, and a retroreflected light beam is generated and transmitted to the first spacecraft; When the first spacecraft receives the return beam, the second side movable optical component of the first spacecraft is controlled to stop spatial scanning, and the return beam is used to correct the adjustment direction of the second side movable optical component of the first spacecraft, thereby generating a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

5. The space capture method for spacecraft bilateral intersatellite laser links according to claim 2, characterized in that: The method of using a spacecraft attitude control system and a movable optical component to iteratively adjust the pointing direction to capture the spacecraft group through an intersatellite laser link to generate multiple bidirectional intersatellite laser links includes: adjusting the orientation of the first movable optical assembly on the second spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the first movable optical assembly on the second spacecraft, determining the adjusted orientation of the first movable optical assembly on the second spacecraft, and generating an outgoing light beam corresponding to the first movable optical assembly on the second spacecraft; adjusting the orientation of the second side movable optical assembly of the second spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the second side movable optical assembly corresponding to the second spacecraft, determining the adjusted orientation of the second side movable optical assembly of the second spacecraft, and generating an outgoing light beam corresponding to the second side movable optical assembly of the second spacecraft; Based on the adjusted direction of the movable optical component on the first side of the second spacecraft, using the outgoing light beam corresponding to the movable optical component on the first side of the second spacecraft to perform spatial scanning on the uncertain area corresponding to the first spacecraft; Based on the adjusted direction of the second side movable optical component of the second spacecraft, using the outgoing light beam corresponding to the second side movable optical component of the second spacecraft to spatially scan the uncertain area corresponding to the third spacecraft; When the third spacecraft receives the outgoing light beam corresponding to the second side movable optical assembly of the second spacecraft, the third spacecraft uses the outgoing light beam corresponding to the second side movable optical assembly of the second spacecraft to correct the direction of the second side movable optical assembly of the third spacecraft, and generates a return light beam corresponding to the second side movable optical assembly of the third spacecraft and transmits it to the second spacecraft; When the first spacecraft receives an outgoing light beam corresponding to the first side movable optical component of the second spacecraft, the first spacecraft uses the outgoing light beam corresponding to the first side movable optical component of the second spacecraft to correct the direction of the first side movable optical component of the first spacecraft, and generates a retroreflected light beam corresponding to the first side movable optical component of the first spacecraft and transmits it to the second spacecraft; When the second spacecraft receives the retroreflected light beam corresponding to the second side movable optical assembly of the third spacecraft and the retroreflected light beam corresponding to the first side movable optical assembly of the first spacecraft, controlling the first side movable optical assembly and the second side movable optical assembly of the second spacecraft to stop spatial scanning; Based on the retroreflected light beam corresponding to the second side movable optical assembly of the third spacecraft and the retroreflected light beam corresponding to the first side movable optical assembly of the first spacecraft, alternately using the spacecraft attitude control system and the first side movable optical assembly and the second side movable optical assembly of the second spacecraft to iteratively correct the attitude of the second spacecraft, the adjusted orientation of the first side movable optical assembly, and the adjusted orientation of the second side movable optical assembly, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft, and a bidirectional intersatellite laser link between the second spacecraft and the third spacecraft; adjusting the orientation of the second movable optical assembly on the first spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the second movable optical assembly corresponding to the first spacecraft, determining the adjusted orientation of the second movable optical assembly on the first spacecraft, and generating an outgoing light beam corresponding to the second movable optical assembly on the first spacecraft; Based on the adjusted direction of the movable optical component on the second side of the first spacecraft, using the outgoing light beam corresponding to the movable optical component on the second side of the first spacecraft to perform spatial scanning on the uncertain area corresponding to the third spacecraft; When the third spacecraft receives the outgoing light beam corresponding to the second side movable optical component of the first spacecraft, the spacecraft attitude control system and the first side movable optical component and the second side movable optical component of the third spacecraft are alternately used to iteratively correct the attitude of the third spacecraft, the adjustment direction of the first side movable optical component, and the adjustment direction of the second side movable optical component, and generate a retroreflected light beam corresponding to the first side movable optical component and the retroreflected light beam corresponding to the second side movable optical component of the third spacecraft, which are emitted to the first spacecraft; When the first spacecraft receives the retroreflected light beam corresponding to the first side movable optical component and the retroreflected light beam corresponding to the second side movable optical component of the third spacecraft, controlling the second side movable optical component of the first spacecraft to stop spatial scanning; Based on the reflected light beam corresponding to the first side movable optical component and the reflected light beam corresponding to the second side movable optical component of the third spacecraft, the spacecraft attitude control system and the first side movable optical component and the second side movable optical component of the first spacecraft are alternately used to iteratively correct the attitude of the first spacecraft, the direction of the first side movable optical component, and the adjusted direction of the second side movable optical component, and generate a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

6. The space capture method for spacecraft bilateral intersatellite laser links according to claim 2, characterized in that: The method of using the unilateral intersatellite laser link space capture method and the pointing degree of freedom constraint method to capture the intersatellite laser link of the spacecraft group to generate multiple bidirectional intersatellite laser links includes: adjusting the orientation of the first side movable optical assembly of the second spacecraft based on a guidance law in an uncertainty region in a yaw-pitch coordinate system of the first side movable optical assembly corresponding to the second spacecraft, determining the adjusted orientation of the first side movable optical assembly of the second spacecraft, and generating an outgoing light beam; Based on the adjusted direction of the movable optical component on the first side of the second spacecraft, using the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the third spacecraft; When the third spacecraft receives the outgoing light beam, the third spacecraft corrects the orientation of the second side movable optical component of the third spacecraft based on the outgoing light beam, and generates a retroreflected light beam to be transmitted to the second spacecraft; When the second spacecraft receives the retroreflected light beam, the movable optical assembly on the first side of the second spacecraft is controlled to stop spatial scanning, and the adjustment direction of the movable optical assembly on the first side of the second spacecraft is corrected using the retroreflected light beam, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the third spacecraft; determining a pointing error of the second side movable optical assembly of the second spacecraft based on the corrected actual direction of the outgoing light beam emitted by the first side movable optical assembly of the second spacecraft; Determining, based on the pointing error of the second side movable optical assembly of the second spacecraft, a guidance law for the second spacecraft in an uncertainty region in a roll coordinate system around the pointing angle of the second side movable optical assembly, corresponding to the second spacecraft; adjusting the orientation of the second movable optical assembly on the second side of the second spacecraft based on a guidance law in an uncertainty region in a roll coordinate system around the orientation of the movable optical assembly on the first side of the second spacecraft, determining the adjusted orientation of the second movable optical assembly on the second side of the second spacecraft, and generating an outgoing light beam; Based on the adjusted direction of the movable optical component on the second side of the second spacecraft, using the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the first spacecraft; When the first spacecraft receives the outgoing light beam, the first spacecraft corrects the orientation of the movable optical component on the first side of the first spacecraft based on the outgoing light beam, and generates a retroreflected light beam to be transmitted to the second spacecraft; When the second spacecraft receives the retroreflected light beam, controlling the second side movable optical component of the second spacecraft to stop spatial scanning, and using the retroreflected light beam to correct the adjustment direction of the second side movable optical component of the second spacecraft, thereby generating a bidirectional intersatellite laser link between the second spacecraft and the first spacecraft; determining a pointing error of a second side movable optical assembly of the first spacecraft based on the corrected actual direction of the outgoing light beam emitted by the first side movable optical assembly of the first spacecraft; Determining, based on the pointing error of the second movable optical assembly on the first spacecraft, a guidance law for the first spacecraft in an uncertainty region in a roll coordinate system around the pointing angle of the second movable optical assembly on both sides of the first spacecraft; Adjusting the orientation of the second movable optical assembly on the first spacecraft based on a guidance law in an uncertainty region in a roll coordinate system around the orientation of the first movable optical assembly on the second side of the first spacecraft based on the included orientation angle of the second movable optical assembly on the first spacecraft, determining the adjusted orientation of the second movable optical assembly on the first spacecraft, and generating an outgoing light beam; Based on the adjusted direction of the movable optical component on the second side of the first spacecraft, using the outgoing light beam to perform spatial scanning on the uncertain area corresponding to the third spacecraft; When the third spacecraft receives the outgoing light beam, the third spacecraft corrects the orientation of the movable optical component on the first side of the third spacecraft based on the outgoing light beam, and generates a retroreflected light beam to be transmitted to the first spacecraft; When the first spacecraft receives the return beam, the second side movable optical component of the first spacecraft is controlled to stop spatial scanning, and the return beam is used to correct the adjustment direction of the second side movable optical component of the first spacecraft, thereby generating a bidirectional intersatellite laser link between the first spacecraft and the third spacecraft.

7. A spacecraft dual-side intersatellite laser link space capture system, characterized in that: Applied to a spacecraft assembly, the system comprises: An acquisition module is used to acquire key indicator data of a capture task and determine whether the key indicator data of the capture task meets a preset first capture condition, a preset second capture condition, or a preset third capture condition; a first capture module, configured to, when the capture mission key indicator data satisfies the preset first capture condition, perform intersatellite laser link capture on the spacecraft group using a unilateral intersatellite laser link space capture method and a guidance law coordinate system conversion method, thereby generating a plurality of bidirectional intersatellite laser links; a second capture module configured to, when the capture mission key indicator data satisfies the preset second capture condition, perform intersatellite laser link capture on the spacecraft group using a spacecraft attitude control system and a movable optical component iterative pointing adjustment method to generate multiple bidirectional intersatellite laser links; The third capture module is used to perform intersatellite laser link capture on the spacecraft group using the unilateral intersatellite laser link space capture method and the pointing degree of freedom constraint method when the key indicator data of the capture mission meets the preset third capture condition, thereby generating multiple bidirectional intersatellite laser links.

8. A computer device, characterized in that: The method comprises a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the processor performs the steps of the space capture method of the spacecraft bilateral intersatellite laser link according to any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed, the space capture method of the spacecraft bilateral inter-satellite laser link according to any one of claims 1 to 6 is implemented.

10. A computer program product, characterized in that The computer program product includes a computer program stored on a non-transitory computer-readable storage medium, wherein the computer program includes program instructions, wherein when the program instructions are executed by a computer, the computer is caused to execute the space capture method for a spacecraft bilateral inter-satellite laser link according to any one of claims 1 to 6.

Images