Spacecraft formation tracking control method, device, equipment and medium

Abstract

The invention discloses a spacecraft formation tracking control method, device, equipment and medium, relates to the technical field of spacecraft control, is applied to a controller in a target spacecraft formation, and comprises the steps: determining each topological neighbor set according to the interaction connectivity of each spacecraft in the target spacecraft formation, inputting a potential collision set in the topological neighbor set into a preset formula constructed based on an artificial potential function, and inputting the output collision avoidance control information into a preset formula constructed based on controller design parameters to obtain an initial formation tracking control signal; the design parameters are designed based on an immersion and invariant algorithm and a preset performance function; processing the initial formation tracking control signal based on an event triggering mechanism so as to obtain a control error input signal by using the obtained final formation tracking control signal; and when the control error input signal meets a preset triggering condition, the collision avoidance control information is transmitted to an actuator of each spacecraft, and tracking control is realized. And accurate tracking and low-cost control are carried out on the spacecraft formation.

Description

Technical Field

[0001] The present invention relates to the field of spacecraft control technology, and in particular to a spacecraft formation tracking control method, device, equipment and medium. Background Art

[0002] Multi-spacecraft formation flying is a method of distributing the functions of a large spacecraft across multiple smaller spacecraft. By forming a spacecraft cluster, members can share information, collaborate, and jointly complete flight missions. Compared to a single spacecraft, a spacecraft formation can improve system reliability, robustness, and launch flexibility while reducing costs. Therefore, research on multi-spacecraft formation flying is of great significance. Multi-spacecraft formation flying refers to the use of multiple spacecraft in orbit to form a system with a specific formation configuration. The spacecraft are interconnected through intersatellite communications and work together to complete the formation flight mission. Compared with traditional single spacecraft, multi-spacecraft formation flying offers advantages such as greater flexibility, higher reliability, and lower cost.

[0003] Multi-spacecraft formation flight primarily involves two aspects: formation reconfiguration and formation maintenance. Considering the varying configurations required for different missions, formation reconfiguration aims to create a suitable formation configuration. Formation maintenance aims to maintain the desired formation configuration despite multiple external disturbances, ensuring the successful completion of the mission.

[0004] In summary, how to accurately track and cost-effectively control a spacecraft formation is a problem to be solved in this field. Summary of the Invention

[0005] In view of this, the present invention aims to provide a spacecraft formation tracking and control method, apparatus, device, and medium to accurately track and cost-effectively control a spacecraft formation. The specific solution is as follows:

[0006] In a first aspect, the present application discloses a spacecraft formation tracking control method, which is applied to a controller in a target spacecraft formation, comprising:

[0007] determining a topological neighbor set of each spacecraft according to the current interactive connectivity between the spacecraft in the target spacecraft formation, and screening a potential collision set that meets a preset possible collision condition from the topological neighbor set;

[0008] Inputting the potential collision set into a preset collision avoidance control information acquisition formula constructed based on an artificial potential function to output collision avoidance control information;

[0009] Inputting the collision avoidance control information into a preset initial formation tracking control signal acquisition formula constructed based on design parameters of the controller to obtain an initial formation tracking control signal; wherein the design parameters are parameters designed based on an immersion and invariance algorithm and a preset performance function;

[0010] processing the initial formation tracking control signal based on an event trigger mechanism to obtain a final formation tracking control signal, and obtaining a control error input signal using the final formation tracking control signal;

[0011] When the control error input signal meets a preset trigger condition, the collision avoidance control information is transmitted to the actuator of each spacecraft, so that the actuator can track and control the target spacecraft formation based on the collision avoidance control information.

[0012] Optionally, screening out a potential collision set that meets a preset possible collision condition from the topological neighbor set includes:

[0013] determining the relative distances between the spacecraft in the target spacecraft formation;

[0014] Target spacecraft whose relative distance is not less than a preset potential collision distance and not greater than a preset safety distance are screened out from the topological neighbor set, and a set consisting of the target spacecraft is determined as a potential collision set.

[0015] Optionally, the preset collision avoidance control information acquisition formula is:

[0016] ;

[0017] in, is the collision avoidance control information of spacecraft i, is the potential collision set of spacecraft i, is the control gain of the collision avoidance control information, is spacecraft j, is the position vector of spacecraft i, is the gradient of the position vector along spacecraft i, is the artificial potential function, is the relative distance between spacecraft i and spacecraft j.

[0018] Optionally, constructing the artificial potential function includes:

[0019] Constructing an action function whose independent variable is relative distance and whose constants are preset safety distance and preset potential collision distance, and constructing the artificial potential function based on the action function;

[0020] The expression of the action function is:

[0021] ;

[0022] in, is the action function value, is the relative distance between spacecraft i and spacecraft j, To set a safe distance, To preset the potential collision distance, is the first positive constant.

[0023] Optionally, the design parameters include a diagonal matrix, a formation tracking control law, and a first gain coefficient; wherein the first gain coefficient is a ratio of mass to a target weight sum, the target weight sum is a sum of a first weight sum and a second weight sum, the first weight sum is a weight between a current spacecraft and an adjacent spacecraft in the target spacecraft formation, and the second weight sum is a second weight sum between the current spacecraft and the leader spacecraft;

[0024] The formation tracking control law is:

[0025] ;

[0026] in, is the formation tracking control law, is the first gain coefficient, is the mass of spacecraft i, is the target weight and, 、 is the second gain coefficient of the controller, 、 is a diagonal matrix, is the topological neighbor set, An improved implicit manifold defined based on a preset performance control function, are parameters adjusted based on controller simulation results, is the trigger threshold, is spacecraft j, is the element of the adjacency matrix of spacecraft i and spacecraft j, is the estimated value of the expansion state, is the element in the leader adjacency matrix of spacecraft i, is the acceleration of the leader of the spacecraft formation, is the current final formation tracking control signal of spacecraft j, is an estimate of the total observer error, For auxiliary adjustment items, 、 is the performance function, is the global error, is the gain constant, is a column vector whose elements are 1.

[0027] Optionally, processing the initial formation tracking control signal based on an event trigger mechanism to obtain a final formation tracking control signal, and obtaining a control error input signal using the final formation tracking control signal includes:

[0028] Preprocessing the initial formation tracking control signal using a piecewise function to obtain a preprocessed formation tracking control signal;

[0029] performing discrete processing on the pre-processed formation tracking control signal based on a function corresponding to an event trigger mechanism to obtain a final formation tracking control signal;

[0030] determining a difference between the pre-processed formation tracking control signal and the final formation tracking control signal as a control error input signal;

[0031] The piecewise function is:

[0032] ;

[0033] in, is the initial formation tracking control signal, For the pre-processed formation tracking control signal, is a parameter in the controller for adjusting the strength of the initial formation tracking control signal;

[0034] The function corresponding to the event triggering mechanism is:

[0035] ;

[0036] in, For the final formation tracking control signal, For the pre-processed formation tracking control signal, The time when the event trigger mechanism is triggered.

[0037] Optionally, the preset trigger condition is:

[0038] ;

[0039] Where t is time, The time for transmitting collision avoidance control information to the actuator, is the control error input signal, are parameters adjusted based on controller simulation results, is the trigger threshold, Tracking control signals for the final formation.

[0040] In a second aspect, the present application discloses a spacecraft formation tracking control device, which is applied to a controller in a target spacecraft formation, comprising:

[0041] a set screening module, configured to determine a topological neighbor set of each spacecraft based on the current interactive connectivity between the spacecraft in the target spacecraft formation, and screen out a potential collision set that meets a preset possible collision condition from the topological neighbor set;

[0042] a collision avoidance information acquisition module, configured to input the potential collision set into a preset collision avoidance control information acquisition formula constructed based on an artificial potential function to output collision avoidance control information;

[0043] an initial control signal acquisition module, configured to input the collision avoidance control information into a preset initial formation tracking control signal acquisition formula constructed based on design parameters of the controller, to obtain an initial formation tracking control signal; wherein the design parameters are parameters designed based on an immersion and invariance algorithm and a preset performance function;

[0044] a final control signal acquisition module, configured to process the initial formation tracking control signal based on an event trigger mechanism to obtain a final formation tracking control signal, and to obtain a control error input signal using the final formation tracking control signal;

[0045] The tracking control module is used to transmit the collision avoidance control information to the actuator of each spacecraft when the control error input signal meets the preset trigger condition, so that the actuator can track and control the target spacecraft formation based on the collision avoidance control information.

[0046] In a third aspect, the present application discloses an electronic device, comprising:

[0047] Memory, used to store computer programs;

[0048] A processor is used to execute the computer program to implement the steps of the aforementioned disclosed spacecraft formation tracking control method.

[0049] In a fourth aspect, the present application discloses a computer-readable storage medium for storing a computer program; wherein, when the computer program is executed by a processor, the steps of the aforementioned disclosed spacecraft formation tracking control method are implemented.

[0050] The beneficial effects of the present application are as follows: the present application is applied to a controller in a target spacecraft formation, comprising: determining a topological neighbor set of each spacecraft based on the current interactive connectivity between the spacecraft in the target spacecraft formation, and screening out a potential collision set that meets preset possible collision conditions from the topological neighbor set; inputting the potential collision set into a preset collision avoidance control information acquisition formula constructed based on an artificial potential function to output collision avoidance control information; inputting the collision avoidance control information into a preset initial formation tracking control signal acquisition formula constructed based on the design parameters of the controller to obtain an initial formation tracking control signal; wherein the design parameters are parameters designed based on an immersion and invariance algorithm and a preset performance function; processing the initial formation tracking control signal based on an event trigger mechanism to obtain a final formation tracking control signal, and using the final formation tracking control signal to obtain a control error input signal; when the control error input signal meets a preset trigger condition, transmitting the collision avoidance control information to the actuator of each spacecraft, so that the actuator tracks and controls the target spacecraft formation based on the collision avoidance control information. It can be seen that the present application determines the topological neighbor set according to the current interactive connectivity, that is, determines the topological neighbor set according to whether information interaction can be carried out between spacecraft, and screens out the potential collision set that meets the preset possible collision conditions from the topological neighbor set. Next, the collision avoidance control information is obtained by using the preset collision avoidance control information acquisition formula constructed based on the artificial potential function, and then the initial formation tracking control signal is obtained by using the preset initial formation tracking control signal acquisition formula, because the design parameters based on the preset initial formation tracking control signal acquisition formula are designed based on the immersion and invariance algorithm and the preset performance function, that is, the present application introduces the immersion and invariance theory and the preset performance theory. In theory, stable and precise tracking and control of the spacecraft formation can be achieved. Furthermore, the initial formation tracking control signal is processed based on the event trigger mechanism to obtain the final formation tracking control signal, and the control error input signal is obtained by using the final formation tracking control signal. Only when the control error input signal meets the preset trigger condition, the collision avoidance control information is transmitted to the actuator of each spacecraft, that is, the information is updated so that the actuator can track and control the target spacecraft formation based on the collision avoidance control information. In other words, the present application only updates and interacts with information when necessary, which will not affect the flight of the formation and can also reduce the control cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the present application 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 merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without any creative work.

[0052] Figure 1 This is a flow chart of a spacecraft formation tracking control method disclosed in this application;

[0053] Figure 2 A schematic diagram of a specific spacecraft position disclosed in this application;

[0054] Figure 3 This is a schematic structural diagram of a spacecraft formation tracking control device disclosed in this application;

[0055] Figure 4 This is a structural diagram of an electronic device disclosed in this application. DETAILED DESCRIPTION

[0056] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. 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 are within the scope of protection of the present invention.

[0057] Multi-spacecraft formation flying is a method of distributing the functions of a large spacecraft across multiple smaller spacecraft. By forming a spacecraft cluster, members can share information, collaborate, and jointly complete flight missions. Compared to a single spacecraft, a spacecraft formation can improve system reliability, robustness, and launch flexibility while reducing costs. Therefore, research on multi-spacecraft formation flying is of great significance. Multi-spacecraft formation flying refers to the use of multiple spacecraft in orbit to form a system with a specific formation configuration. The spacecraft are interconnected through intersatellite communications and work together to complete the formation flight mission. Compared with traditional single spacecraft, multi-spacecraft formation flying offers advantages such as greater flexibility, higher reliability, and lower cost.

[0058] Multi-spacecraft formation flight primarily involves two aspects: formation reconfiguration and formation maintenance. Considering the varying configurations required for different missions, formation reconfiguration aims to create a suitable formation configuration. Formation maintenance aims to maintain the desired formation configuration despite multiple external disturbances, ensuring the successful completion of the mission.

[0059] To this end, this application provides a spacecraft formation tracking and control solution to accurately track and control the spacecraft formation at low cost.

[0060] See also Figure 1 As shown, the embodiment of the present application discloses a spacecraft formation tracking control method, which is applied to a controller in a target spacecraft formation, including:

[0061] Step S11: determining a topological neighbor set of each spacecraft according to the current interactive connectivity between the spacecraft in the target spacecraft formation, and screening out a potential collision set that meets a preset possible collision condition from the topological neighbor set.

[0062] Topological neighbor set It is determined by whether the members can exchange information. For example, if spacecraft i and spacecraft j can communicate, then it is considered that Therefore, the topological neighbor set of each spacecraft is determined based on the current interactive connectivity between the spacecraft in the target spacecraft formation. .

[0063] In this embodiment, the method of screening out a potential collision set that meets preset possible collision conditions from the topological neighbor set includes: determining the relative distance of each spacecraft in the target spacecraft formation; screening out each target spacecraft whose relative distance is not less than a preset potential collision distance and not greater than a preset safety distance from the topological neighbor set, and determining the set composed of each of the target spacecraft as a potential collision set.

[0064] Determine the relative distance between each spacecraft in the target spacecraft formation, specifically the position vector of spacecraft i and the position vector of spacecraft j , then the position vector of spacecraft i relative to spacecraft j is , the relative distance between spacecraft i and spacecraft j is ,Right now ,when When it is established, it indicates that a collision has occurred between the formation members. , it means that spacecraft i and j have the possibility of collision, such as Figure 2 A specific schematic diagram of the spacecraft position is shown, and the relative distance of the spacecraft from the topological neighbor set is not less than the preset potential collision distance. And no greater than the preset safety distance The target spacecraft of each target spacecraft is determined as the potential collision set ,Right now .

[0065] Step S12: inputting the potential collision set into a preset collision avoidance control information acquisition formula constructed based on an artificial potential function to output collision avoidance control information.

[0066] In this embodiment, the preset collision avoidance control information acquisition formula is:

[0067] ;

[0068] in, is the collision avoidance control information of spacecraft i, is the potential collision set of spacecraft i, is the control gain of the collision avoidance control information, is spacecraft j, is the position vector of spacecraft i, is the gradient of the position vector along spacecraft i, is the artificial potential function, is the relative distance between spacecraft i and spacecraft j.

[0069] The potential collision set is input into the preset collision avoidance control information acquisition formula constructed based on the artificial potential function to output the collision avoidance control information , The negative sign in front means that spacecraft i exerts a repulsive force in the opposite direction of motion on spacecraft j that may collide with it. The collision avoidance control input The design is to ensure that the distance between neighbor members is always greater than the specified safety distance to avoid internal collisions.

[0070] In this embodiment, constructing the artificial potential function includes: constructing an action function whose independent variables are relative distance and constants are preset safety distance and preset potential collision distance, and constructing the artificial potential function based on the action function;

[0071] The expression of the action function is:

[0072] ;

[0073] in, is the action function value, is the relative distance between spacecraft i and spacecraft j, To set a safe distance, To preset the potential collision distance, is the first positive constant.

[0074] First positive constant is a very small positive constant to ensure that the denominator of the action function is not 0 and always remains bounded. The expression of the action function shows that when Small enough and Sometimes, there are Established.

[0075] Step S13: Inputting the collision avoidance control information into a preset initial formation tracking control signal acquisition formula constructed based on the design parameters of the controller to obtain an initial formation tracking control signal; wherein the design parameters are parameters designed based on an immersion and invariance algorithm and a preset performance function.

[0076] In this embodiment, the design parameters include a diagonal matrix, a formation tracking control law, and a first gain coefficient; wherein the first gain coefficient is a ratio between mass and a target weight sum, the target weight sum is the sum of a first weight sum and a second weight sum, the first weight sum is a weight between a current spacecraft and an adjacent spacecraft in the target spacecraft formation, and the second weight sum is a second weight sum between the current spacecraft and the leader spacecraft;

[0077] The formation tracking control law is:

[0078] ;

[0079] in, is the formation tracking control law, is the first gain coefficient, is the mass of spacecraft i, is the target weight and, 、 is the second gain coefficient of the controller, 、 is a diagonal matrix, is the topological neighbor set, An improved implicit manifold defined based on a preset performance control function, are parameters adjusted based on controller simulation results, is the trigger threshold, is spacecraft j, is the element of the adjacency matrix of spacecraft i and spacecraft j, is the estimated value of the expansion state, is the element in the leader adjacency matrix of spacecraft i, is the acceleration of the leader of the spacecraft formation, is the current final formation tracking control signal of spacecraft j, is an estimate of the total observer error, For auxiliary adjustment items, 、 is the performance function, is the global error, is the gain constant, is a column vector whose elements are 1.

[0080] Furthermore, the target weights and is the sum of the first weight sum and the second weight sum. The first weight sum is the weight between the current spacecraft and the adjacent spacecraft in the target spacecraft formation, that is, the weight sum of the neighboring nodes of member i. The second weight sum is the second weight sum between the current spacecraft i and the leader spacecraft, that is, the connection weight sum between member i and the leader. The target weight sum The formula for obtaining it is:

[0081] ;

[0082] in, is the element of the adjacency matrix of spacecraft i and spacecraft j, is the element in the leader adjacency matrix of spacecraft i.

[0083] The formula for obtaining the preset initial formation tracking control signal based on the controller design parameters is as follows:

[0084] ;

[0085] Where, is the initial formation tracking control signal, that is, the control input signal that can achieve collision-free formation tracking without any triggering conditions. is the formation tracking control law, is the first gain coefficient, is the mass of spacecraft i, is the target weight and, is the diagonal matrix related to the preset performance control, is the collision avoidance control information of spacecraft i. Furthermore, the expression of the preset initial formation tracking control signal acquisition formula can also be:

[0086] ;

[0087] Where, is the initial formation tracking control signal, is the formation tracking control law, is the first gain coefficient, is the mass of spacecraft i, is the target weight and, 、 is the second gain coefficient of the controller, 、 is a diagonal matrix, is the topological neighbor set, An improved implicit manifold defined based on a preset performance control function, are parameters adjusted based on controller simulation results, is the trigger threshold, is spacecraft j, is the element of the adjacency matrix of spacecraft i and spacecraft j, is the estimated value of the expansion state, is the element in the leader adjacency matrix of spacecraft i, is the acceleration of the leader of the spacecraft formation, is the current final formation tracking control signal of spacecraft j, is an estimate of the total observer error, For auxiliary adjustment items, 、 is the performance function, is the global error, is the gain constant, is a column vector with elements equal to 1, is the diagonal matrix related to the preset performance control, is the collision avoidance control information of spacecraft i.

[0088] Step S14: processing the initial formation tracking control signal based on an event triggering mechanism to obtain a final formation tracking control signal, and using the final formation tracking control signal to obtain a control error input signal.

[0089] In this embodiment, the processing of the initial formation tracking control signal based on the event trigger mechanism to obtain a final formation tracking control signal, and obtaining a control error input signal using the final formation tracking control signal, includes: preprocessing the initial formation tracking control signal using a piecewise function to obtain a preprocessed formation tracking control signal; discretely processing the preprocessed formation tracking control signal based on a function corresponding to the event trigger mechanism to obtain a final formation tracking control signal; and determining the difference between the preprocessed formation tracking control signal and the final formation tracking control signal as a control error input signal; the piecewise function is:

[0090] ;

[0091] in, is the initial formation tracking control signal, For the pre-processed formation tracking control signal, is a parameter in the controller for adjusting the strength of the initial formation tracking control signal;

[0092] The function corresponding to the event triggering mechanism is:

[0093] ;

[0094] in, For the final formation tracking control signal, For the pre-processed formation tracking control signal, The time when the event trigger mechanism is triggered.

[0095] For a multi-spacecraft formation system, communication between members depends on wireless networks, so the communication bandwidth is limited. At this time, continuous controller updates may cause communication congestion, increase the probability of packet loss, cause communication delays, and waste communication resources. To solve this problem, this embodiment introduces an event trigger mechanism. Therefore, the initial formation tracking control signal is first preprocessed using a piecewise function, that is, the initial formation tracking control signal can be amplified or weakened to obtain a preprocessed formation tracking control signal, and then the preprocessed formation tracking control signal is discretely processed based on the function corresponding to the event trigger mechanism to obtain the final formation tracking control signal. That is, the role of the event trigger mechanism is to convert the continuous preprocessed formation tracking control signal into a discrete final formation tracking control signal.

[0096] Furthermore, the pre-processed formation tracking control signal and final formation tracking control signals The difference between them is determined as the control error input signal, that is, the control error input signal is .

[0097] Step S15: When the control error input signal meets a preset trigger condition, the collision avoidance control information is transmitted to the actuator of each spacecraft, so that the actuator tracks and controls the target spacecraft formation based on the collision avoidance control information.

[0098] In this embodiment, the preset trigger condition is:

[0099] ;

[0100] Where t is time, The time for transmitting collision avoidance control information to the actuator, is the control error input signal, are parameters adjusted based on controller simulation results and , is the trigger threshold, Tracking control signals for the final formation.

[0101] Furthermore, the trigger threshold The expression is:

[0102] ;

[0103] Where, And is the parameter to be designed, that is, it is also a parameter adjusted based on the controller simulation results. Obviously, It is always bounded. From the expression of the preset trigger condition, it can be seen that only when the defined trigger condition is met can the controller be updated and information exchange between members be carried out, that is, the collision avoidance control information is transmitted to the actuator of each spacecraft, so that the actuator can track and control the target spacecraft formation based on the collision avoidance control information. This will greatly reduce the controller update frequency and reduce unnecessary communication resource consumption.

[0104] The beneficial effects of the present application are as follows: the present application is applied to a controller in a target spacecraft formation, comprising: determining a topological neighbor set of each spacecraft based on the current interactive connectivity between the spacecraft in the target spacecraft formation, and screening out a potential collision set that meets preset possible collision conditions from the topological neighbor set; inputting the potential collision set into a preset collision avoidance control information acquisition formula constructed based on an artificial potential function to output collision avoidance control information; inputting the collision avoidance control information into a preset initial formation tracking control signal acquisition formula constructed based on the design parameters of the controller to obtain an initial formation tracking control signal; wherein the design parameters are parameters designed based on an immersion and invariance algorithm and a preset performance function; processing the initial formation tracking control signal based on an event trigger mechanism to obtain a final formation tracking control signal, and using the final formation tracking control signal to obtain a control error input signal; when the control error input signal meets a preset trigger condition, transmitting the collision avoidance control information to the actuator of each spacecraft, so that the actuator tracks and controls the target spacecraft formation based on the collision avoidance control information. It can be seen that the present application determines the topological neighbor set according to the current interactive connectivity, that is, determines the topological neighbor set according to whether information interaction can be carried out between spacecraft, and screens out the potential collision set that meets the preset possible collision conditions from the topological neighbor set. Next, the collision avoidance control information is obtained by using the preset collision avoidance control information acquisition formula constructed based on the artificial potential function, and then the initial formation tracking control signal is obtained by using the preset initial formation tracking control signal acquisition formula, because the design parameters based on the preset initial formation tracking control signal acquisition formula are designed based on the immersion and invariance algorithm and the preset performance function, that is, the present application introduces the immersion and invariance theory and the preset performance theory. In theory, stable and precise tracking and control of the spacecraft formation can be achieved. Furthermore, the initial formation tracking control signal is processed based on the event trigger mechanism to obtain the final formation tracking control signal, and the control error input signal is obtained by using the final formation tracking control signal. Only when the control error input signal meets the preset trigger condition, the collision avoidance control information is transmitted to the actuator of each spacecraft, that is, the information is updated so that the actuator can track and control the target spacecraft formation based on the collision avoidance control information. In other words, the present application only updates and interacts with information when necessary, which will not affect the flight of the formation and can also reduce the control cost.

[0105] The controller design process of this application is described below. First, a low-order target system with desired performance needs to be selected and a mapping relationship between the initial system and the target system needs to be constructed. ,in, represents the target system, Represents the initial system; then, an implicit manifold is defined based on the mapping relationship , express, express, Next, we design the I&I (Immersion & Invariance) controller. , Represents the controller, It represents the auxiliary function introduced when designing the controller to ensure that the designed manifold has invariance and attractiveness, so that the state of the initial controlled system can be attracted to the manifold surface through the state of the target system. The specific process is as follows:

[0106] First, assume The desired position vector of spacecraft i relative to the virtual leader, represents the position vector of spacecraft i, represents the velocity vector of spacecraft i, is the corresponding velocity vector, then , at this time, the position tracking error and velocity tracking error of spacecraft i can be expressed as: 、 ;definition is the trajectory of the formation center in the LVLH coordinate system (local vertical local horizontal), is the expected position vector of spacecraft i relative to the formation center, then according to the vector addition rule, we have Assuming that the desired formation configuration is time-invariant, then is a constant. At this time, the specific form of the global formation tracking error and velocity error of spacecraft i can be expressed as:

[0107] ;

[0108] Where, represents the global formation tracking error, represents the speed error, represents the speed of the leader in the spacecraft formation. Considering the possible unknown uncertainties and external disturbances in the model, the following extended state observer can be designed:

[0109] ;

[0110] Where: They are and estimates; The expansion state defined of which , represents a skew-symmetric matrix, represents the dynamic damping matrix, represents the gravity vector, where It includes all possible internal and external uncertainties of the system. is the observer gain, which satisfies the polynomial , represents the frequency domain symbol, here is the observer bandwidth. Assume is the estimation error of the extended state observer. According to the convergence of the extended state observer verified in existing literature, It is bounded and can be estimated through adaptive technology and fed back to the controller for compensation, thereby further improving the performance of the controller.

[0111] Next, the position tracking error and velocity tracking error are derived to obtain the dynamic equation of the error system:

[0112] ;

[0113] Where, is the mass of spacecraft i, is the target weight and, For the final formation tracking control signal, is the element in the leader adjacency matrix of spacecraft i, is the acceleration of the leader of the spacecraft formation, is the current final formation tracking control signal of spacecraft j, is the mass of spacecraft j, is the element of the adjacency matrix of spacecraft i and spacecraft j, is a topological neighbor set, and .

[0114] In order to constrain the transient and steady-state performance of the error, according to the principle of preset performance control, the performance function is first defined to constrain the transient and steady-state performance of the global error:

[0115] ;

[0116] In the formula, the performance function and It is the main factor that determines the transient and steady-state performance of the global error. Here, in order to make the global error converge within the time specified by the user, the specified time performance function in the existing work is used to constrain the performance of the error signal, and its expression is:

[0117] ;

[0118] Where, represents the pre-specified convergence time, is the second positive constant given by the user, , it can be understood that the proposed performance function is able to Converges to , so if the designed controller can satisfy the performance function inequality constraint, the global error It can converge to and Within the constraints, the expected formation performance can be achieved:

[0119] ;

[0120] Since the additional constraints of the performance function inequality increase the difficulty of controller design, the following homeomorphic mapping function is introduced to deconstrain the additional constraints:

[0121] ;

[0122] Where, 、 represents the error vector after deconstraint, and the derivative of the above formula can be obtained:

[0123] ;

[0124] when , the performance function inequality constraint can be satisfied, that is, when the designed controller is guaranteed to ensure Bounded, the desired specified time stability can be achieved.

[0125] Since the formation controller designed in this embodiment is based on the I&I technology, the following mapping function is given according to the four steps of the I&I algorithm mentioned above: 、 、 、 、 , and define a reduced-order asymptotically stable target system, expressed as:

[0126] ;

[0127] in Indicates the status of the target system, Is a gain constant. Obviously, the origin is an asymptotically stable equilibrium point of the target system. The mapping between the global error system and the target system is constructed as:

[0128] ;

[0129] in, is a function to be designed, i.e., a parameter adjusted according to the controller simulation results, the following immersion conditions can be designed:

[0130] ;

[0131] Where, ,Right now , then the implicit manifold can be defined as follows:

[0132] ;

[0133] Where, represents the implicit manifold, represents the mapping function. Currently, most control methods based on I&I theory can only ensure that the performance of the controlled system is consistent with that of the target system. That is, the tracking error converges asymptotically, and the transient and steady-state behavior of the controlled system can only be guaranteed by repeated adjustment of the controller parameters. This means that satisfactory performance often corresponds to a large amount of time consumption. Preset performance control based on a specified time performance function can effectively solve these problems. Based on preset performance control, the improved implicit manifold can be defined as follows:

[0134] ;

[0135] Based on this, the formation tracking control law of the distributed formation tracking controller based on I&I can be designed as follows: :

[0136] ;

[0137] Where, is the controller gain coefficient; is a column vector with elements equal to 1; are parameters adjusted based on controller simulation results, is the trigger threshold. It can be seen that in the controller, the observer error is unknown and needs to be estimated online. Here, in order to facilitate subsequent estimation, it is assumed that the observer error is slowly time-varying relative to the system state. Definition is the total observer error, that is Since the designed formation controller is based on I&I control technology, the adaptive I&I theory is introduced here to complete the total observer error. Compared with the traditional adaptive estimation, the adaptive I&I theory adds an auxiliary adjustment term to the adaptive law. , which provides greater design freedom to improve the estimation accuracy. The estimate of can be expressed as , the corresponding estimation error expression is:

[0138] ;

[0139] Taking the derivative of the above formula, we can get:

[0140] ;

[0141] For ease of understanding, we can and It can be regarded as a 3×3 diagonal matrix, whose elements are and ,in and They are The mth element of , so the following adaptive estimation law can be designed:

[0142] ;

[0143] in, , so we can get the following expression:

[0144] ;

[0145] To ensure the estimation error Convergence of auxiliary adjustment items It can be defined as:

[0146] ;

[0147] Where, is a constant that is adjusted based on the controller simulation results. It should be noted that the column vector The square and cubic power of the vector are the elements that should be calculated. After online estimation of , the following expression can be obtained:

[0148] ;

[0149] Considering that the ultimate goal is to achieve collision-free formation tracking, the final collision-free formation tracking controller The expression can be written as:

[0150] ;

[0151] Where, is the initial formation tracking control signal, is the formation tracking control law, is the first gain coefficient, is the mass of spacecraft i, is the target weight and, 、 is the second gain coefficient of the controller, 、 is a diagonal matrix, is the topological neighbor set, An improved implicit manifold defined based on a preset performance control function, are parameters adjusted based on controller simulation results, is the trigger threshold, is spacecraft j, is the element of the adjacency matrix of spacecraft i and spacecraft j, is the estimated value of the expansion state, is the element in the leader adjacency matrix of spacecraft i, is the acceleration of the leader of the spacecraft formation, is the current final formation tracking control signal of spacecraft j, is an estimate of the total observer error, For auxiliary adjustment items, 、 is the performance function, is the global error, is the gain constant, is a column vector with elements equal to 1, is the diagonal matrix related to the preset performance control, is the collision avoidance control information of spacecraft i.

[0152] See also Figure 3 As shown, the embodiment of the present application discloses a spacecraft formation tracking control device, which is applied to a controller in a target spacecraft formation, including:

[0153] A set screening module 11 is configured to determine a topological neighbor set of each spacecraft based on the current interactive connectivity between the spacecraft in the target spacecraft formation, and to screen out a potential collision set that meets a preset possible collision condition from the topological neighbor set;

[0154] a collision avoidance information acquisition module 12, configured to input the potential collision set into a preset collision avoidance control information acquisition formula constructed based on an artificial potential function to output collision avoidance control information;

[0155] an initial control signal acquisition module 13, configured to input the collision avoidance control information into a preset initial formation tracking control signal acquisition formula constructed based on design parameters of the controller, to obtain an initial formation tracking control signal; wherein the design parameters are parameters designed based on an immersion and invariance algorithm and a preset performance function;

[0156] a final control signal acquisition module 14, configured to process the initial formation tracking control signal based on an event trigger mechanism to obtain a final formation tracking control signal, and to obtain a control error input signal using the final formation tracking control signal;

[0157] The tracking control module 15 is used to transmit the collision avoidance control information to the actuator of each spacecraft when the control error input signal meets the preset trigger condition, so that the actuator can track and control the target spacecraft formation based on the collision avoidance control information.

[0158] The beneficial effects of the present application are as follows: the present application is applied to a controller in a target spacecraft formation, comprising: determining a topological neighbor set of each spacecraft based on the current interactive connectivity between the spacecraft in the target spacecraft formation, and screening out a potential collision set that meets preset possible collision conditions from the topological neighbor set; inputting the potential collision set into a preset collision avoidance control information acquisition formula constructed based on an artificial potential function to output collision avoidance control information; inputting the collision avoidance control information into a preset initial formation tracking control signal acquisition formula constructed based on the design parameters of the controller to obtain an initial formation tracking control signal; wherein the design parameters are parameters designed based on an immersion and invariance algorithm and a preset performance function; processing the initial formation tracking control signal based on an event trigger mechanism to obtain a final formation tracking control signal, and using the final formation tracking control signal to obtain a control error input signal; when the control error input signal meets a preset trigger condition, transmitting the collision avoidance control information to the actuator of each spacecraft, so that the actuator tracks and controls the target spacecraft formation based on the collision avoidance control information. It can be seen that the present application determines the topological neighbor set according to the current interactive connectivity, that is, determines the topological neighbor set according to whether information interaction can be carried out between spacecraft, and screens out the potential collision set that meets the preset possible collision conditions from the topological neighbor set. Next, the collision avoidance control information is obtained by using the preset collision avoidance control information acquisition formula constructed based on the artificial potential function, and then the initial formation tracking control signal is obtained by using the preset initial formation tracking control signal acquisition formula, because the design parameters based on the preset initial formation tracking control signal acquisition formula are designed based on the immersion and invariance algorithm and the preset performance function, that is, the present application introduces the immersion and invariance theory and the preset performance theory. In theory, stable and precise tracking and control of the spacecraft formation can be achieved. Furthermore, the initial formation tracking control signal is processed based on the event trigger mechanism to obtain the final formation tracking control signal, and the control error input signal is obtained by using the final formation tracking control signal. Only when the control error input signal meets the preset trigger condition, the collision avoidance control information is transmitted to the actuator of each spacecraft, that is, the information is updated so that the actuator can track and control the target spacecraft formation based on the collision avoidance control information. In other words, the present application only updates and interacts with information when necessary, which will not affect the flight of the formation and can also reduce the control cost.

[0159] Furthermore, an embodiment of the present application also provides an electronic device. Figure 4 This is a structural diagram of an electronic device 20 according to an exemplary embodiment. The content in the diagram should not be considered as any limitation to the scope of application of the present application.

[0160] Figure 4This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Specifically, the device may include: at least one processor 21, at least one memory 22, a power supply 23, a communication interface 24, an input / output interface 25, and a communication bus 26. The memory 22 is used to store a computer program, which is loaded and executed by the processor 21 to implement the relevant steps of the spacecraft formation tracking control method performed by the electronic device as disclosed in any of the aforementioned embodiments.

[0161] In this embodiment, the power supply 23 is used to provide operating voltage for various hardware devices on the electronic device; the communication interface 24 can create a data transmission channel between the electronic device and external devices. The communication protocol it follows is any communication protocol that can be applied to the technical solution of this application and is not specifically limited here; the input and output interface 25 is used to obtain external input data or output data to the outside world. Its specific interface type can be selected according to specific application needs and is not specifically limited here.

[0162] Among them, the processor 21 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 21 can be implemented in at least one hardware form of DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), and PLA (Programmable Logic Array). The processor 21 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 21 may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 21 may also include an AI (Artificial Intelligence) processor, which is used to process computing operations related to machine learning.

[0163] In addition, the memory 22, as a carrier for resource storage, can be a read-only memory, random access memory, disk or CD, etc. The resources stored thereon include an operating system 221, a computer program 222 and data 223, etc. The storage method can be temporary storage or permanent storage.

[0164] The operating system 221 is used to manage and control the hardware devices and computer programs 222 on the electronic device, enabling the processor 21 to calculate and process the massive amount of data 223 in the memory 22. It can be run on Windows, Unix, Linux, or other operating systems. In addition to computer programs capable of implementing the spacecraft formation tracking and control method disclosed in any of the aforementioned embodiments, the computer programs 222 may also include computer programs capable of performing other specific tasks. Data 223 may include data received by the electronic device from external devices, as well as data collected by its own input / output interface 25.

[0165] Furthermore, this application also discloses a computer-readable storage medium for storing a computer program; wherein, when executed by a processor, the computer program implements the aforementioned spacecraft formation tracking and control method. The specific steps of this method can be referred to the corresponding contents disclosed in the aforementioned embodiments and will not be repeated here.

[0166] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from the other embodiments. Reference can be made to the descriptions of the identical or similar parts between the various embodiments. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and the relevant parts can be referred to the descriptions of the methods.

[0167] Professionals may further appreciate that the units and algorithmic steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application. The steps of the method or algorithm described in conjunction with the embodiments disclosed herein can be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module can be placed in random access memory (RAM), memory, read-only memory (ROM), electrically programmable EPROM (Erasable Programmable Read Only Memory), electrically erasable programmable EEPROM (Electrically Erasable Programmable read only memory), registers, hard disk, removable disk, CD-ROM (Compact Disc Read-Only Memory), or any other form of storage medium known in the technical field.

[0168] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or device comprising the element.

[0169] The above is a detailed introduction to the spacecraft formation tracking control method, device, equipment and medium provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for general technical personnel in this field, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A spacecraft formation tracking control method, characterized in that: The controller used in the target spacecraft formation includes: determining a topological neighbor set of each spacecraft according to the current interactive connectivity between the spacecraft in the target spacecraft formation, and screening a potential collision set that meets a preset possible collision condition from the topological neighbor set; Inputting the potential collision set into a preset collision avoidance control information acquisition formula constructed based on an artificial potential function to output collision avoidance control information; Inputting the collision avoidance control information into a preset initial formation tracking control signal acquisition formula constructed based on design parameters of the controller to obtain an initial formation tracking control signal; wherein the design parameters are parameters designed based on an immersion and invariance algorithm and a preset performance function; processing the initial formation tracking control signal based on an event trigger mechanism to obtain a final formation tracking control signal, and obtaining a control error input signal using the final formation tracking control signal; When the control error input signal meets a preset trigger condition, the collision avoidance control information is transmitted to the actuator of each spacecraft, so that the actuator can track and control the target spacecraft formation based on the collision avoidance control information.

2. The spacecraft formation tracking control method according to claim 1, characterized in that: The step of screening out a potential collision set that meets a preset possible collision condition from the topological neighbor set includes: determining the relative distances between the spacecraft in the target spacecraft formation; Target spacecraft whose relative distance is not less than a preset potential collision distance and not greater than a preset safety distance are screened out from the topological neighbor set, and a set consisting of the target spacecraft is determined as a potential collision set.

3. The spacecraft formation tracking control method according to claim 2, characterized in that: The preset collision avoidance control information acquisition formula is: ； in, is the collision avoidance control information of spacecraft i, is the potential collision set of spacecraft i, is the control gain of the collision avoidance control information, is spacecraft j, is the position vector of spacecraft i, is the gradient of the position vector along spacecraft i, is the artificial potential function, is the relative distance between spacecraft i and spacecraft j.

4. The spacecraft formation tracking control method according to claim 3, characterized in that: Constructing the artificial potential function includes: Constructing an action function whose independent variable is the relative distance and whose constants are the preset safety distance and the preset potential collision distance, and constructing the artificial potential function based on the action function; The expression of the action function is: ； in, is the action function value, is the relative distance between spacecraft i and spacecraft j, To set a safe distance, To preset the potential collision distance, is the first positive constant.

5. The spacecraft formation tracking control method according to claim 1, characterized in that: The design parameters include a diagonal matrix, a formation tracking control law, and a first gain coefficient; wherein the first gain coefficient is a ratio between mass and a target weight sum, the target weight sum is a sum of a first weight sum and a second weight sum, the first weight sum is a weight between a current spacecraft and an adjacent spacecraft in the target spacecraft formation, and the second weight sum is a second weight sum between the current spacecraft and the leader spacecraft; The formation tracking control law is: ； in, is the formation tracking control law, is the first gain coefficient, is the mass of spacecraft i, is the target weight and, 、 is the second gain coefficient of the controller, 、 is a diagonal matrix, is the topological neighbor set, An improved implicit manifold defined based on a preset performance control function, are parameters adjusted based on controller simulation results, is the trigger threshold, is spacecraft j, is the element of the adjacency matrix of spacecraft i and spacecraft j, is the estimated value of the expansion state, is the element in the leader adjacency matrix of spacecraft i, is the acceleration of the leader of the spacecraft formation, is the current final formation tracking control signal of spacecraft j, is an estimate of the total observer error, For auxiliary adjustment items, 、 is the performance function, is the global error, is the gain constant, is a column vector whose elements are all 1.

6. The spacecraft formation tracking control method according to claim 1, characterized in that: The processing of the initial formation tracking control signal based on the event triggering mechanism to obtain a final formation tracking control signal, and obtaining a control error input signal using the final formation tracking control signal, includes: Preprocessing the initial formation tracking control signal using a piecewise function to obtain a preprocessed formation tracking control signal; performing discrete processing on the pre-processed formation tracking control signal based on a function corresponding to an event trigger mechanism to obtain a final formation tracking control signal; determining a difference between the pre-processed formation tracking control signal and the final formation tracking control signal as a control error input signal; The piecewise function is: ； in, is the initial formation tracking control signal, For the pre-processed formation tracking control signal, is a parameter in the controller for adjusting the strength of the initial formation tracking control signal; The function corresponding to the event triggering mechanism is: ； in, For the final formation tracking control signal, For the pre-processed formation tracking control signal, The time when the event trigger mechanism is triggered.

7. The spacecraft formation tracking control method according to claim 1, characterized in that: The preset trigger conditions are: ； Where t is time, The time for transmitting collision avoidance control information to the actuator, is the control error input signal, are parameters adjusted based on controller simulation results, is the trigger threshold, Tracking control signals for the final formation.

8. A spacecraft formation tracking control device, characterized in that: The controller used in the target spacecraft formation includes: a set screening module, configured to determine a topological neighbor set of each spacecraft based on the current interactive connectivity between the spacecraft in the target spacecraft formation, and screen out a potential collision set that meets a preset possible collision condition from the topological neighbor set; a collision avoidance information acquisition module, configured to input the potential collision set into a preset collision avoidance control information acquisition formula constructed based on an artificial potential function to output collision avoidance control information; an initial control signal acquisition module, configured to input the collision avoidance control information into a preset initial formation tracking control signal acquisition formula constructed based on design parameters of the controller, to obtain an initial formation tracking control signal; wherein the design parameters are parameters designed based on an immersion and invariance algorithm and a preset performance function; a final control signal acquisition module, configured to process the initial formation tracking control signal based on an event trigger mechanism to obtain a final formation tracking control signal, and to obtain a control error input signal using the final formation tracking control signal; The tracking control module is used to transmit the collision avoidance control information to the actuator of each spacecraft when the control error input signal meets the preset trigger condition, so that the actuator can track and control the target spacecraft formation based on the collision avoidance control information.

9. An electronic device, characterized in that: include: Memory, used to store computer programs; A processor, configured to execute the computer program to implement the steps of the spacecraft formation tracking control method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that Used to store computer programs; wherein, when the computer program is executed by a processor, the steps of the spacecraft formation tracking control method according to any one of claims 1 to 7 are implemented.

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