A multi-spacecraft distributed cooperative vector control distribution method

Abstract

The application discloses a kind of multi-spacecraft distributed cooperative vector control distribution method.The method comprises: establishing the coordinate system of each cell robot in combination spacecraft and the coordinate system of combination spacecraft, and constructing the attitude dynamics model of combination spacecraft;Obtain virtual control signal;Construct the initial vector distribution matrix of each cell robot;The initial vector distribution matrix of each cell robot is distributed optimization, and the target vector distribution matrix of each cell robot is obtained;Based on the target vector distribution matrix of each cell robot, virtual control signal and the rotation matrix of the coordinate system of each cell robot to the coordinate system of combination spacecraft, determine the action torque of the centroid of each cell robot to combination spacecraft.This application solves the technical problems of large amount of calculation and large communication pressure when cell robot cluster controls the attitude takeover of target spacecraft in prior art.

Description

Technical Field

[0001] The present invention relates to the technical field of attitude takeover control of target spacecraft of a cellular robot cluster, and in particular to a multi-spacecraft distributed collaborative vector control allocation method. Background Art

[0002] Traditional solutions for target spacecraft attitude takeover control tasks based on cellular robot swarms often employ centralized control algorithms. In these algorithms, as the number of cellular robots increases, the central node faces enormous communication and computational pressure, and its limited resources become insufficient to meet the corresponding task requirements. To address this issue, researchers proposed a distributed hierarchical takeover control algorithm involving a control cellular robot and several execution cellular robots. All cellular robots are located in the same communication topology network, with each cellular robot acting as a node in the network. The control cellular robot generates the virtual control signals required for attitude adjustment of the combined system and transmits them to each node via the communication topology network. Each node then completes control allocation by exchanging information with neighboring cellular robots, obtaining executable control instructions from the cellular robot hierarchy. The presence of the communication topology significantly reduces the communication and computational pressure on the system compared to traditional centralized algorithms. The algorithm consists of two main steps: control signal generation and distributed control allocation.

[0003] Control signal generation involves deriving the virtual control signals needed to adjust the combined spacecraft's attitude based on its attitude deviations and associated constraints. However, these signals cannot be directly executed and must be distributed to individual cellular robots through control distribution. Because the execution capabilities of a single cellular robot are limited, multiple cellular robots are typically required to coordinate and take over control tasks. To obtain the output signals from each cellular robot, a corresponding control distribution algorithm must be developed.

[0004] Distributed control allocation involves decomposing the virtual control signal through distributed information interaction, so that each cell robot's output vector sum tracks the virtual control signal. Ideally, the direction of each cell robot's output signal should be arbitrary. This requires that the distributed control allocation method should follow the principle of vector allocation. That is, each cell robot obtains the vector allocation matrix through distributed computing and uses this matrix and the virtual control signal information to obtain the cell robot's desired output signal. This greatly ensures the flexibility of the cell robot's output and can also support the optimality of the system in certain indicators. Summary of the Invention

[0005] An embodiment of the present invention provides a multi-spacecraft distributed collaborative vector control allocation method to at least solve the technical problems in the prior art of large computational complexity and high communication pressure when a cellular robot cluster performs attitude takeover control tasks on a target spacecraft.

[0006] According to one aspect of an embodiment of the present invention, a method for allocating distributed collaborative vector control for multiple spacecraft is provided. The method may include: establishing a coordinate system for each cell robot in the combined spacecraft and a coordinate system for the combined spacecraft, and constructing an attitude dynamics model for the combined spacecraft; obtaining a virtual control signal; constructing an initial vector allocation matrix for each cell robot; performing distributed optimization on the initial vector allocation matrix for each cell robot to obtain a target vector allocation matrix for each cell robot; and determining the torque exerted by each cell robot on the center of mass of the combined spacecraft based on the target vector allocation matrix for each cell robot, the virtual control signal, and a rotation matrix from the coordinate system of each cell robot to the coordinate system of the combined spacecraft.

[0007] Optionally, the process of establishing the coordinate system of each cell robot in the combined spacecraft is: setting the coordinate origin of the coordinate system of each cell robot at the center of mass of each cell robot; setting the coordinate axis direction of the coordinate system of each cell robot at the three main axes of inertia of each cell robot.

[0008] Optionally, the process of establishing the coordinate system of the combined spacecraft is: setting the coordinate origin of the coordinate system of the combined spacecraft at the center of mass of the combined spacecraft; and using the coordinate axis direction of the first cell robot in the combined spacecraft as the coordinate axis direction of the coordinate system of the combined spacecraft.

[0009] Optionally, the distributed optimization of the initial vector allocation matrix of each cell robot to obtain the target vector allocation matrix of each cell robot includes: using a sequential quadratic programming optimization algorithm to optimize the initial vector allocation matrix of each cell robot to obtain the target vector allocation matrix of each cell robot.

[0010] Optionally, the method of determining the torque formed by each cell robot on the center of mass of the combined spacecraft based on the target vector allocation matrix of each cell robot, the virtual control signal and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft includes: determining the output of each cell robot based on the target vector allocation matrix of each cell robot, the virtual control signal and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft; and determining the torque formed by each cell robot on the center of mass of the combined spacecraft based on the output of each cell robot.

[0011] Optionally, the output of each cell robot is determined based on the target vector allocation matrix of each cell robot, the virtual control signal and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft, including: taking the product of the target vector allocation matrix of each cell robot, the virtual control signal and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft as the output of each cell robot.

[0012] Optionally, determining the torque formed by each cell robot on the center of mass of the combined spacecraft based on the output of each cell robot includes: determining the sum of the outputs of each cell robot as the torque formed by each cell robot on the center of mass of the combined spacecraft.

[0013] Beneficial effects of the present invention:

[0014] The present invention provides a distributed collaborative vector control allocation method for multiple spacecraft. This method allows each cell robot to control output in any direction, so that the combined spacecraft as a whole can obtain global optimization in some indicators. At the same time, since the present invention adopts distributed computing, the combined spacecraft can comprehensively utilize the computing and communication resources of each cell robot to improve the reliability of the combined spacecraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0016] Figure 1 is a flow chart of a multi-spacecraft distributed cooperative vector control allocation method according to an embodiment of the present invention;

[0017] Figure 2 is a schematic diagram of the coordinate system of each cell robot and the coordinate system of the combined spacecraft according to an embodiment of the present invention;

[0018] Figure 3 is a schematic diagram of an assembled spacecraft according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the embodiments described 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 efforts should fall within the scope of protection of the present invention.

[0020] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and to describe a specific order or sequence. It should be understood that the terms used in this way are interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units that are not explicitly listed or inherent to these processes, methods, products or devices.

[0021] Example 1

[0022] According to an embodiment of the present invention, a method for allocating distributed collaborative vector control of multiple spacecraft is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system containing at least one set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0023] Figure 1 FIG. 1 is a flow chart of a multi-spacecraft distributed cooperative vector control allocation method according to an embodiment of the present invention. Figure 1 As shown, the method may include the following steps:

[0024] Step S101: establish the coordinate system of each cell robot in the combined spacecraft and the coordinate system of the combined spacecraft, and construct an attitude dynamics model of the combined spacecraft.

[0025] In the technical solution provided in the above step S101 of the present invention, Figure 2 Schematic diagram of the coordinate system of each cell robot and the coordinate system of the combined spacecraft according to an embodiment of the present invention, as shown in FIG. Figure 2 As shown, the coordinate system of each cell robot , the coordinate system of the combined spacecraft is , according to the Newton-Euler equation, the attitude dynamics model of the combined spacecraft is constructed:

[0026]

[0027] in, represents the attitude of the combined spacecraft described by the Modified Rodrigues Parameter (MRP) method, represents the set of real numbers, express The time derivative, is the kinematic transformation matrix, represents the angular velocity of the combined spacecraft in the inertial system, They are the combined spacecraft in the inertial system The angular velocity of the axis, express The time derivative, It is a vector The antisymmetric matrix for vector cross product operation, Indicates the combined spacecraft in the body coordinate system The moment of inertia in It represents the equivalent virtual control signal, which is the torque of each cell robot's output acting on the center of mass of the combined spacecraft. The description in which The expression is:

[0028]

[0029] in, represents the unit vector along the combined spacecraft rotation axis, Indicates along the axis of rotation The angle of rotation.

[0030] The expression is:

[0031]

[0032] in, represents the three-dimensional identity matrix, It is a vector The specific expression of the antisymmetric matrix for vector cross multiplication is:

[0033]

[0034] Pair Vector The expression of the antisymmetric matrix for vector cross multiplication is:

[0035]

[0036] Figure 3 is a schematic diagram of a combined spacecraft according to an embodiment of the present invention, such as Figure 3 As shown in FIG, all cell robots no longer move relative to the target spacecraft after being attached to the surface of the target spacecraft.

[0037] Step S102: Acquire a virtual control signal.

[0038] In the technical solution provided in step S102 of the present invention, the virtual control signal is in the combined spacecraft body coordinate system Description in It is an upper-level control signal generated by the upper-level control of each cell robot based on the attitude error information and related constraints of the combined spacecraft to adjust the attitude of the combined spacecraft. This signal acts on the center of mass of the combined spacecraft, but cannot be directly executed. Because the signal is realized by the superposition of the control outputs of multiple cell robots, it is necessary to decompose the signal through control distribution to obtain the control instructions of each cell robot, among which, , The virtual control signal is in the combined spacecraft body coordinate system middle Description of the axis.

[0039] Step S103: constructing an initial vector distribution matrix for each cell robot.

[0040] In the technical solution provided in step S103 of the present invention, the initial vector distribution matrix of each cell robot is constructed as follows: , For each cell robot Vector distribution factor on the axis.

[0041] Step S104: Distributed optimization is performed on the initial vector allocation matrix of each cell robot to obtain the target vector allocation matrix of each cell robot.

[0042] In the technical solution provided in step S104 of the present invention, the distributed optimization of the initial vector allocation matrix of each cell robot is defined as a multi-objective optimization problem:

[0043]

[0044] in, , Represents each cell robot The installation matrix, T represents the transpose, For each cell robot The reaction wheel saturation matrix, where For each cell robot In the coordinate system middle Energy balance factor on the axis, Cell Robot along Three coordinate axes ( The angular velocity of the three mutually perpendicular reaction wheels is The expression in Cell Robot along Three coordinate axes ( ) Place the reaction wheel at an angular velocity of Description in The three elements in the represent cell robots along Three coordinate axes ( ) The maximum angular velocity of the upper reaction wheel, , Represents a vector Take the absolute value of each element, Indicates the maximum speed of the reaction wheel; cell robot along middle The higher the saturation of the reaction wheel on the shaft, the higher the corresponding energy balance factor The larger the value, the more balanced the saturation of each cell robot will be, thus avoiding premature saturation of individual cell robots and thus reducing the reliability of the system. Represents the minimum value of the elements in the vector, , whose elements are The upper bound of the corresponding position element in and satisfies the output constraint ,in, , represents the infinity norm of a vector, Represents the maximum execution capability of a single reaction wheel of the cellular robot. The purpose of this constraint is to prevent the control allocation result from exceeding the cellular robot execution capabilities, is a symbolic function; each cell robot The expression of the reaction wheel saturation matrix is:

[0045]

[0046] Step S105 , based on the target vector allocation matrix of each cell robot, the virtual control signal and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft, determine the torque generated by each cell robot on the center of mass of the combined spacecraft.

[0047] In the technical solution provided in the above step S105 of the present invention, the target vector allocation matrix of each cell robot, the virtual control signal and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft are calculated to obtain the torque generated by each cell robot on the center of mass of the combined spacecraft.

[0048] The above method of this embodiment is further introduced below.

[0049] As an optional embodiment, step S101, the process of establishing the coordinate system of each cell robot in the combined spacecraft is: setting the coordinate origin of the coordinate system of each cell robot at the center of mass of each cell robot; setting the coordinate axis direction of the coordinate system of each cell robot at the three main axes of inertia of each cell robot.

[0050] In this embodiment, if Figure 2 As shown, the origin of the coordinate system of the cell robot 1 is set at the center of mass of each cell robot 1 ; Set the coordinate axis direction of the coordinate system of the cell robot 1 to the three principal axes of inertia of the cell robot 1 ( )direction, Figure 2 The other cell robots are set up in the same way as Cell Robot 1.

[0051] As an optional embodiment, step S101, the process of establishing the coordinate system of the combined spacecraft is: setting the coordinate origin of the coordinate system of the combined spacecraft at the center of mass of the combined spacecraft; and using the coordinate axis direction of the first cell robot in the combined spacecraft as the coordinate axis direction of the coordinate system of the combined spacecraft.

[0052] In this embodiment, the coordinate origin of the combined spacecraft's coordinate system is set at the mass center of the combined spacecraft. , the coordinate axis direction of the first cell robot in the combined spacecraft As the coordinate axis direction of the combined spacecraft coordinate system .

[0053] As an optional embodiment, step S104, the distributed optimization of the initial vector allocation matrix of each cell robot to obtain the target vector allocation matrix of each cell robot includes: using a sequential quadratic programming optimization algorithm to optimize the initial vector allocation matrix of each cell robot to obtain the target vector allocation matrix of each cell robot.

[0054] In this embodiment, the sequential quadratic programming optimization algorithm is used to solve the initial vector allocation matrix of each cell robot to obtain the target vector allocation matrix of each cell robot. .

[0055] As an optional embodiment, step S105, based on the target vector allocation matrix of each cell robot, the virtual control signal and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft, determines the torque formed by each cell robot on the center of mass of the combined spacecraft, including: based on the target vector allocation matrix of each cell robot, the virtual control signal and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft, determining the output of each cell robot; based on the output of each cell robot, determining the torque formed by each cell robot on the center of mass of the combined spacecraft.

[0056] In this embodiment, the target vector allocation matrix of each cell robot, the virtual control signal and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft are calculated to obtain the output of each cell robot, and the output of each cell robot is calculated to obtain the torque formed by each cell robot on the center of mass of the combined spacecraft.

[0057] As an optional embodiment, the output of each cell robot is determined based on the target vector allocation matrix of each cell robot, the virtual control signal and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft, including: the product of the target vector allocation matrix of each cell robot, the virtual control signal and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft is determined as the output of each cell robot.

[0058] In this embodiment, the product of the target vector distribution matrix of each cell robot, the virtual control signal, and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft is determined as the output of each cell robot:

[0059]

[0060] in, For the output of each cell robot, , Represents the coordinate system of each cell robot To the combined spacecraft coordinate system The rotation matrix of the cell robot The installation matrix, is the target vector allocation matrix, where the target vector allocation matrix has the same expression as the initial vector allocation matrix and is the optimal solution of the initial vector allocation matrix. The output of each cell robot.

[0061] As an optional embodiment, the method of determining the torque formed by each cell robot on the center of mass of the combined spacecraft based on the output of each cell robot includes: determining the sum of the outputs of each cell robot as the torque formed by each cell robot on the center of mass of the combined spacecraft.

[0062] In this embodiment, the sum of the outputs of each cell robot is determined as the expression for the torque exerted by each cell robot on the center of mass of the combined spacecraft:

[0063]

[0064] in, The torque exerted by each cell robot on the center of mass of the combined spacecraft.

[0065] In an embodiment of the present invention, a coordinate system of each cell robot in a combined spacecraft and a coordinate system of the combined spacecraft are established, and an attitude dynamics model of the combined spacecraft is constructed; a virtual control signal is obtained; an initial vector allocation matrix of each cell robot is constructed; the initial vector allocation matrix of each cell robot is distributedly optimized to obtain a target vector allocation matrix of each cell robot; based on the target vector allocation matrix of each cell robot, the virtual control signal and the rotation matrix from the coordinate system of each cell robot to the coordinate system of the combined spacecraft, the torque formed by each cell robot on the center of mass of the combined spacecraft is determined, thereby solving the technical problems of large computational complexity and high communication pressure when a cell robot cluster performs attitude takeover control tasks on a target spacecraft in the prior art, and achieving the technical effect of reducing computational complexity and reducing communication pressure by adopting distributed computing to fully utilize the computing and communication resources of each robot in the combined spacecraft when performing attitude takeover control tasks on a target spacecraft.

[0066] The serial numbers of the above embodiments of the present invention are for description only and do not represent the advantages or disadvantages of the embodiments.

[0067] In the above embodiments of the present invention, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0068] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only exemplary. For example, the division of units can be 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 units or modules, which can be electrical or other forms.

[0069] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple units. Some or all of the units may be selected to achieve the purpose of the present embodiment according to actual needs.

[0070] In addition, the functional units in various embodiments of the present invention may be integrated into a first processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0071] The above are only preferred embodiments of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A multi-spacecraft distributed cooperative vector control allocation method, characterized in that: include: Establish the coordinate system of each cell robot in the combined spacecraft and the coordinate system of the combined spacecraft, and construct the attitude dynamics model of the combined spacecraft; Get virtual control signal; Construct the initial vector allocation matrix for each cell robot; Perform distributed optimization on the initial vector allocation matrix of each cell robot to obtain the target vector allocation matrix of each cell robot; Based on the target vector distribution matrix of each cell robot, the virtual control signal and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft, the torque exerted by each cell robot on the center of mass of the combined spacecraft is determined; The method of determining the torque exerted by each cell robot on the center of mass of the combined spacecraft based on the target vector allocation matrix of each cell robot, the virtual control signal, and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft includes: The product of the target vector distribution matrix of each cell robot, the virtual control signal and the rotation matrix of the coordinate system of each cell robot to the coordinate system of the combined spacecraft is determined as the output of each cell robot; Based on the output of each cell robot, the torque exerted by each cell robot on the center of mass of the combined spacecraft is determined.

2. The method according to claim 1, characterized in that The process of establishing the coordinate system of each cell robot in the combined spacecraft is as follows: The coordinate origin of the coordinate system of each cell robot is set at the center of mass of each cell robot; The coordinate axis directions of the coordinate system of each cell robot are set in the directions of the three principal axes of inertia of each cell robot.

3. The method according to claim 2, characterized in that The process of establishing the coordinate system of the combined spacecraft is as follows: Setting the coordinate origin of the combined spacecraft's coordinate system at the combined spacecraft's center of mass; The coordinate axis direction of the first cell robot in the combined spacecraft is used as the coordinate axis direction of the coordinate system of the combined spacecraft.

4. The method according to claim 1, wherein The distributed optimization of the initial vector allocation matrix of each cell robot to obtain the target vector allocation matrix of each cell robot includes: The sequential quadratic programming optimization algorithm is used to optimize the initial vector allocation matrix of each cell robot to obtain the target vector allocation matrix of each cell robot.

5. The method according to claim 1, wherein The step of determining the torque exerted by each cell robot on the center of mass of the combined spacecraft based on the output of each cell robot comprises: The sum of the outputs of each cell robot is determined as the torque exerted by each cell robot on the center of mass of the combined spacecraft.

6. A computer system, characterized in that include: One or more processors, and a computer-readable storage medium for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors are enabled to implement the method of claim 1.

7. A computer-readable storage medium, characterized in that Computer-executable instructions are stored, and when the instructions are executed, they are used to implement the method of claim 1.

8. A computer program product, characterized in that The invention comprises computer executable instructions, which are used to implement the method of claim 1 when the instructions are executed.

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