Stratospheric airship model-free sliding mode control method, device, equipment and medium

Abstract

The invention discloses a stratospheric airship model-free sliding mode control method, device and equipment and a medium, and relates to the field of automatic control. The method comprises the following steps: calculating a pseudo-partial derivative matrix estimated value based on a stratospheric airship attitude control model, calculating an angular velocity control input vector at the current moment according to an angular velocity control input vector at the previous moment, an attitude expected value vector at the next moment, an airship attitude quantity at the current moment and a pseudo-partial derivative matrix, and performing accumulative calculation based on a forgetting factor mechanism to obtain a control channel input vector in a historical state; a control channel input vector in a current state is calculated according to an attitude expected value vector at a current moment and an airship attitude quantity, and angular velocity sliding mode control input at the current moment is calculated based on a pseudo-partial derivative matrix estimated value, a sliding mode surface and a sliding mode surface arrival law; and calculating an actual control channel input vector according to the control channel input vectors in the historical state and the current state and the angular velocity sliding mode control input at the current moment. The application improves the control precision and robustness.

Description

Technical Field

[0001] The present application relates to the field of automatic control, and in particular to a method, device, equipment and medium for model-free sliding mode control of a stratospheric airship. Background Art

[0002] In recent years, research on the stratosphere has attracted much attention. As a type of aircraft that can fully utilize the unique meteorological characteristics of the region, stratospheric airships are increasingly favored by the commercial and scientific research fields. Among them, the control system of stratospheric airships constitutes an important research direction.

[0003] The main goal of the stratospheric airship control system is attitude stability. Current technologies mainly include PID control, backstepping control, sliding mode control, etc. However, most methods rely on accurate mathematical models and require an accurate description of the airship dynamics. Since airship dynamics models often have complex dynamic coupling relationships, accurate modeling is extremely challenging. In addition, the disturbances in the stratospheric environment are unknown, and inaccurate stratospheric wind field forecasts may seriously affect the stability of attitude control. Therefore, it is very difficult to construct an accurate airship dynamics model under the serious influence of model uncertainty and environmental disturbances. This requires in-depth research on the attitude control of stratospheric airships under model uncertainty. Summary of the invention

[0004] The purpose of the present application is to provide a model-free sliding mode control method, device, equipment and medium for a stratospheric airship, which can control the attitude of the stratospheric airship when the dynamic model is completely unknown, greatly enhancing the robustness and control accuracy of the stratospheric airship attitude control system.

[0005] To achieve the above objectives, this application provides the following solutions:

[0006] In a first aspect, the present application provides a model-free sliding mode control method for a stratospheric airship, comprising:

[0007] Establish a stratospheric airship attitude control model for the target airship;

[0008] Based on the stratospheric airship attitude control model, calculating the estimated value of the pseudo partial derivative matrix at the current moment;

[0009] Calculate the angular velocity control input vector at the current moment according to the angular velocity control input vector at the previous moment, the attitude expected value vector at the next moment, the attitude value of the airship at the current moment, and the pseudo partial derivative matrix of the control system;

[0010] Based on the forgetting factor mechanism, the control channel input vector of the historical state is calculated according to the angular velocity control input vector at the initial moment, the attitude expectation value vector at each historical moment in the historical period, and the airship attitude quantity; the control channel input vector of the current state is calculated according to the attitude expectation value vector at the current moment and the airship attitude quantity;

[0011] Calculate the current angular velocity sliding mode control input based on the estimated value of the pseudo partial derivative matrix, the sliding mode surface and the sliding mode surface arrival law;

[0012] According to the control channel input vector in the historical state, the control channel input vector in the current state and the angular velocity sliding mode control input at the current moment, an actual control channel input vector is calculated; the actual control channel input vector is used to control the attitude of the stratospheric airship.

[0013] In a second aspect, the present application provides a model-free sliding mode control device for a stratospheric airship, comprising:

[0014] A stratospheric airship attitude control model building module is used to: build a stratospheric airship attitude control model of a target airship;

[0015] A pseudo partial derivative matrix estimation value calculation module is used to calculate the pseudo partial derivative matrix estimation value at the current moment based on the stratospheric airship attitude control model;

[0016] The angular velocity control input vector calculation module is used to calculate the angular velocity control input vector at the current moment according to the angular velocity control input vector at the previous moment, the attitude expected value vector at the next moment, the attitude value of the airship at the current moment, and the pseudo partial derivative matrix of the control system;

[0017] The control channel input vector calculation module is used to: calculate the control channel input vector of the historical state based on the forgetting factor mechanism according to the angular velocity control input vector at the initial moment, the attitude expectation value vector at each historical moment in the historical period, and the airship attitude quantity; calculate the control channel input vector at the current state according to the attitude expectation value vector at the current moment and the airship attitude quantity;

[0018] The sliding mode control input calculation module is used to calculate the current angular velocity sliding mode control input based on the pseudo partial derivative matrix estimation value, the sliding mode surface and the sliding mode surface arrival law at the current moment;

[0019] The actual control channel input vector calculation module is used to calculate the actual control channel input vector according to the control channel input vector in the historical state, the control channel input vector in the current state and the angular velocity sliding mode control input at the current moment; the actual control channel input vector is used to control the attitude of the stratospheric airship.

[0020] In a third aspect, the present application provides a computer device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the above-mentioned stratospheric airship model-free sliding mode control method.

[0021] In a fourth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned stratospheric airship model-free sliding mode control method.

[0022] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0023] The present application provides a stratospheric airship model-free sliding mode control method, device, equipment and medium, which are integrated into a model-free control architecture through an adaptive forgetting factor, thereby enhancing the transition performance of the stratospheric airship attitude control; by combining model-free control and sliding mode control, the stratospheric airship attitude control is realized in a state where the dynamic model is completely unknown, and the robustness of the stratospheric airship attitude control system is greatly enhanced; compared with the existing airship attitude control technology, there is no need to perform dynamic modeling on the stratospheric airship, and the control accuracy is better; good control effects can be obtained under different expected attitude vectors, and the control vector finally obtained is simple and easy to input into an actual control mechanism, and accurate control of the stratospheric airship attitude can be achieved when the dynamic model is completely unknown. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 This is an application environment diagram of a model-free sliding mode control method for a stratospheric airship in one embodiment of the present application;

[0026] Figure 2 A schematic flow chart of a model-free sliding mode control method for a stratospheric airship provided in one embodiment of the present application;

[0027] Figure 3 A detailed flow chart of a model-free sliding mode control method for a stratospheric airship provided in one embodiment of the present application;

[0028] Figure 4 A schematic diagram of a stratospheric airship provided in an embodiment of the present application;

[0029] Figure 5A schematic diagram of functional modules of a model-free sliding mode control device for a stratospheric airship provided in one embodiment of the present application;

[0030] Figure 6 A schematic diagram of the structure of a computer device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0031] 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 described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0032] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0033] The stratospheric airship model-free sliding mode control method provided in the embodiment of the present application can be applied to Figure 1In the application environment shown. Among them, the terminal 102 communicates with the server 104 through the network. The data storage system can store the data that the server 104 needs to process. The data storage system can be set up separately, integrated on the server 104, or placed on the cloud or other servers. The terminal 102 can send the historical moment angular velocity control input vector of the target airship to the server 104. After the server 104 receives the historical moment angular velocity control input vector of the target airship, the server 104 establishes a stratospheric airship attitude control model of the target airship, calculates the estimated value of the pseudo-partial derivative matrix at the current moment based on the stratospheric airship attitude control model, calculates the current moment angular velocity control input vector according to the angular velocity control input vector at the previous moment, the attitude expected value vector at the next moment, the current moment airship attitude quantity and the pseudo-partial derivative matrix of the control system, and based on the forgetting factor mechanism, calculates the angular velocity control input vector according to the initial moment angular velocity The control channel input vector of the historical state is calculated based on the attitude expected value vector of each historical moment in the historical period and the attitude quantity of the airship; the control channel input vector of the current state is calculated based on the attitude expected value vector and the attitude quantity of the airship at the current moment; the angular velocity sliding mode control input of the current moment is calculated based on the estimated value of the pseudo partial derivative matrix at the current moment, the sliding mode surface and the arrival law of the sliding mode surface; the actual control channel input vector is calculated based on the control channel input vector of the historical state, the control channel input vector of the current state and the angular velocity sliding mode control input at the current moment, and the actual control channel input vector is used to control the attitude of the stratospheric airship. The server 104 can feed back the obtained actual control channel input vector for the target airship to the terminal 102. In addition, in some embodiments, the stratospheric airship model-free sliding mode control method can also be implemented by the server 104 or the terminal 102 alone, such as the terminal 102 can directly perform the stratospheric airship model-free sliding mode control processing, or the server 104 can obtain the angular velocity control input vector of the target airship at the historical moment from the data storage system and perform the stratospheric airship model-free sliding mode control processing.

[0034] The terminal 102 may be, but is not limited to, various desktop computers and laptop computers. The server 104 may be implemented as an independent server or a server cluster consisting of multiple servers, or may be a cloud server.

[0035] In an exemplary embodiment, Figure 2 and 3 As shown, a model-free sliding mode control method for a stratospheric airship is provided. The method is executed by a computer device, and specifically can be executed by a computer device such as a terminal or a server alone, or can be executed by a terminal and a server together. In the embodiment of the present application, the method is applied to Figure 1 The server 104 in the example is used for explanation, and the steps include the following steps 201 to 206.

[0036] in:

[0037] Step 201: Establish a stratospheric airship attitude control model of the target airship.

[0038] Step 202: Based on the stratospheric airship attitude control model, calculate the estimated value of the pseudo partial derivative matrix at the current moment.

[0039] Step 203: Calculate the current moment angular velocity control input vector according to the previous moment angular velocity control input vector, the next moment attitude expected value vector, the current moment airship attitude value and the pseudo partial derivative matrix of the control system.

[0040] Step 204: Based on the forgetting factor mechanism, the control channel input vector of the historical state is calculated according to the angular velocity control input vector at the initial moment, the attitude expectation value vector at each historical moment in the historical period, and the airship attitude quantity; the control channel input vector in the current state is calculated according to the attitude expectation value vector at the current moment and the airship attitude quantity.

[0041] Step 205: Calculate the current angular velocity sliding mode control input based on the pseudo partial derivative matrix estimate, the sliding mode surface, and the sliding mode surface arrival law.

[0042] Step 206: Calculate the actual control channel input vector according to the control channel input vector in the historical state, the control channel input vector in the current state and the angular velocity sliding mode control input at the current moment; the actual control channel input vector is used to control the attitude of the stratospheric airship.

[0043] By implementing the above steps 201 to 206, the adaptive forgetting factor is integrated into the model-free control architecture, thereby enhancing the transition performance of the stratospheric airship attitude control; by combining the model-free control and the sliding mode control, the attitude of the stratospheric airship is controlled in a state where the dynamic model is completely unknown, thereby greatly enhancing the robustness of the stratospheric airship attitude control system; compared with the existing airship attitude control technology, there is no need to perform dynamic modeling on the stratospheric airship, and the control accuracy is better; good control effects can be obtained under different expected attitude vectors, and the control vector finally obtained is simple and easy to input into the actual control mechanism, and accurate control of the stratospheric airship attitude can be achieved when the dynamic model is completely unknown.

[0044] Stratospheric airships Figure 4 As shown, Figure 4 In the equation, ERF represents the inertial coordinate system, BRF represents the hull coordinate system, O represents the center of mass of the airship, x represents the X-axis of the hull coordinate system, y represents the Y-axis of the hull coordinate system, z represents the Z-axis of the hull coordinate system, and O represents the center of mass of the airship. g represents the origin of the inertial coordinate system, x gIndicates the inertial coordinate system X axis, y g represents the Y axis of the inertial coordinate system, z g represents the Z axis of the inertial coordinate system, p represents the roll angular velocity of the airship, q represents the pitch angular velocity of the airship, r represents the yaw angular velocity of the airship, and v represents the lateral velocity of the airship.

[0045] In another exemplary embodiment of the present application, the specific process of the above step 201 is as follows:

[0046] The model-free control equation for the angular velocity of the stratospheric airship is established as follows:

[0047]

[0048] Among them, Ω(k) is the airship attitude at the current time k, τ ω (k) is the input of the current attitude control channel of the airship, Ω(k+1) represents the attitude of the target airship at the next moment, that is, the attitude of the target airship at the moment k+1; n y and n u They represent the state quantity and control channel order of the unknown system respectively. In the attitude control system of the stratospheric airship, n y and n u Both are 3; Represent the unknown dynamic equations of the airship.

[0049] By analyzing and deforming the attitude control system of the stratospheric airship, the following form can be obtained:

[0050] ΔΩ(k+1)=θ c (k)Δτ ω (k) (2);

[0051] Among them, ΔΩ(k+1) is the change vector of the attitude value from the current time k to the next time k+1, θ c (k) is the pseudo partial derivative matrix of the attitude control system of the stratospheric airship at the current moment k, Δτ ω (k) is the change vector of the control channel input between the current moment k and the previous moment k-1.

[0052] In step 202, the pseudo partial derivative matrix estimation value under the above-mentioned stratospheric airship attitude control model is calculated, and the calculation formula of the pseudo partial derivative matrix estimation value is as follows:

[0053]

[0054] in, and are the estimated values ​​of the pseudo partial derivative matrices at the current moment k and the previous moment k-1, η and μ are design parameters, ΔΩ(k) is the change vector of the attitude value from the previous moment k-1 to the current moment k, Δτω (k-1) is the change vector of the control channel input at the previous moment k-1 and the previous moment k-2.

[0055] Then calculate the control input vector at the current moment. The calculation formula is as follows:

[0056]

[0057] Among them, Ω * (k+1) represents the expected value vector of the posture at the next moment, and λ and ρ are design parameters.

[0058] According to the changes at the moment, the control channel input vectors in the historical state and the current state can be given respectively:

[0059]

[0060] Among them, U old The control channel input vector representing the historical state, U new represents the control channel input vector in the current state, i represents the historical moments i=1, 2, 3...k-1.

[0061] This application introduces a forgetting factor mechanism when calculating the control channel input vectors in the historical state and the current state to integrate the adaptive forgetting factor into the model-free control architecture. The calculation formula of the control channel input vectors in the historical state and the current state after the introduction of the forgetting factor mechanism is as follows:

[0062]

[0063] in, is the forgetting factor at time k-1, τ ω (0) is the angular velocity control input vector at the initial moment, is the forgetting factor of each historical moment i, Ω * (i+1) represents the expected value vector of the attitude at the next moment of the historical time i, Ω(i) represents the attitude of the airship at the historical time i, Ω * (k+1) represents the expected value vector of the attitude at time k+1, Ω(k) represents the attitude of the airship at time k, is the estimated value of the pseudo partial derivative matrix at each historical moment i.

[0064] The control channel input vectors in the historical state and the current state after the introduction of the forgetting factor mechanism are summed up to obtain the model-free control input at the current moment as follows:

[0065]

[0066] Among them, τωMFA (k) is the angular velocity model-free control input at the current time k.

[0067] In another exemplary embodiment of the present application, the above step 205 is replaced by the following steps 301 to 303:

[0068] Step 301: Calculate the attitude tracking error according to the attitude expectation value vector and the airship attitude quantity at the current moment;

[0069] Step 302: defining a sliding surface according to the posture tracking error;

[0070] Step 303: Calculate the current angular velocity sliding mode control input according to the pseudo partial derivative matrix estimate, the sliding mode surface and the sliding mode surface arrival law.

[0071] The posture tracking error is calculated as follows:

[0072] e(k)=Ω * (k)-Ω(k) (8);

[0073] Among them, e(k) is the current k posture tracking error, Ω * (k) represents the expected value vector of the attitude at the current time k, and Ω(i) represents the attitude of the airship at each historical time i.

[0074] The sliding surface s(k) is defined as follows:

[0075] s(k)=e(k) (9);

[0076] In another example of the present application, the expression of the designed sliding surface arrival law is as follows:

[0077] s(k+1)-s(k)=-qTs(k)-εTsign(s(k)) (10);

[0078] Among them, s(k+1) is the sliding surface state at the next moment of the current moment k, s(k) is the sliding surface state at the current moment k, q and ε are design parameters, T is the sampling time, and sign is the sign function.

[0079] Based on the above-mentioned current pseudo partial derivative matrix estimation value, sliding surface and sliding surface arrival law, the current angular velocity sliding mode control input is obtained. The calculation formula of the current angular velocity sliding mode control input is as follows:

[0080] τ ωSM (k) = θ c (k) -1 [Ω * (k+1)-Ω(k)-(1-qT)s(k)+εTsign(s(k))] (11);

[0081] Among them, τ ωSM (k) is the sliding mode control input at the current moment k, is the estimated value of the pseudo partial derivative matrix at the current moment k, Ω * (k+1) represents the expected value vector of the posture at the next moment after the current moment k.

[0082] In another exemplary embodiment of the present application, the above step 206 is replaced by the following steps 401 to 402:

[0083] Step 401: Calculate the current angular velocity model-free control input according to the control channel input vector in the historical state and the control channel input vector in the current state;

[0084] Step 402: Perform weighted summation on the current angular velocity model-free control input and the current angular velocity sliding mode control input to obtain an actual control channel input vector.

[0085] That is, the control channel input vector of the historical state, the control channel input vector of the current state and the angular velocity sliding mode control input at the current moment are weighted according to different weighting coefficients to obtain the actual control channel input vector, that is, the control matrix is ​​corrected as follows. The calculation formula of the actual control channel input vector is as follows:

[0086] τ ω (k) = τ ωMFA (k)+Γτ ωSM (k) (12);

[0087] Among them, τ ω (k) is the actual control channel input vector at the current time k, and Γ is the diagonal weight vector.

[0088] The attitude of the stratospheric airship is controlled by the actual control channel input vector obtained by the above calculation. Under the state of a given desired attitude vector, the present application calculates the control input vectors of the two control methods, model-free control and sliding mode control, respectively, calculates these two vectors by weighting, and finally obtains the input vector of the attitude control channel for practical application, and synergistically combines the sliding mode control with the adaptive model-free control technology to synthesize a robust model-free control solution, which improves the control performance and robustness of the stratospheric airship in unknown and complex environments, and has a simple overall structure and is easy to implement in engineering.

[0089] The present application also provides an application scenario, which applies the above-mentioned stratospheric airship model-free sliding mode control method. Specifically: the stratospheric airship model-free sliding mode control method provided in this embodiment can be applied in the stratospheric airship attitude control scenario. The stratospheric airship attitude control scenario includes a target airship determination link, an actual control channel input vector calculation link and an attitude control link; from the target airship determination link, enter the actual control channel input vector calculation link, obtain the corresponding actual control channel input vector, and enter the downstream attitude control link. The stratospheric airship model-free sliding mode control method provided in this embodiment belongs to the actual control channel input vector calculation link. Specifically, in the actual control channel input vector calculation link process for the stratospheric airship, a stratospheric airship attitude control model of the target airship can be established, and the pseudo partial derivative matrix estimate value at the current moment is calculated based on the stratospheric airship attitude control model, and the angular velocity control input vector at the current moment is calculated according to the angular velocity control input vector at the previous moment, the attitude expected value vector at the next moment, the airship attitude quantity at the current moment, and the pseudo partial derivative matrix of the control system. Based on the forgetting factor mechanism, the control channel input vector of the historical state is calculated according to the angular velocity control input vector at the initial moment, the attitude expected value vector and the airship attitude quantity at each historical moment in the historical period, and the control channel input vector at the current state is calculated according to the attitude expected value vector and the airship attitude quantity at the current moment. The angular velocity sliding mode control input at the current moment is calculated based on the pseudo partial derivative matrix estimate value at the current moment, the sliding mode surface and the sliding mode surface arrival law. The actual control channel input vector is calculated according to the control channel input vector of the historical state, the control channel input vector of the current state, and the angular velocity sliding mode control input at the current moment. The actual control channel input vector is used to control the stratospheric airship attitude.

[0090] Based on the same inventive concept, the embodiment of the present application also provides a stratospheric airship model-free sliding mode control device for implementing the stratospheric airship model-free sliding mode control method involved above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above method, so the specific limitations of one or more stratospheric airship model-free sliding mode control device embodiments provided below can refer to the limitations of the stratospheric airship model-free sliding mode control method above, and will not be repeated here.

[0091] In an exemplary embodiment, Figure 5 As shown, a model-free sliding mode control device for a stratospheric airship is provided, comprising:

[0092] The stratospheric airship attitude control model establishment module T1 is used to: establish the stratospheric airship attitude control model of the target airship;

[0093] The pseudo partial derivative matrix estimation value calculation module T2 is used to calculate the pseudo partial derivative matrix estimation value at the current moment based on the stratospheric airship attitude control model;

[0094] The angular velocity control input vector calculation module T3 is used to calculate the angular velocity control input vector at the current moment according to the angular velocity control input vector at the previous moment, the attitude expected value vector at the next moment, the attitude value of the airship at the current moment, and the pseudo partial derivative matrix of the control system;

[0095] The control channel input vector calculation module T4 is used to: calculate the control channel input vector of the historical state based on the forgetting factor mechanism according to the angular velocity control input vector at the initial moment, the attitude expectation value vector at each historical moment in the historical period, and the airship attitude quantity; calculate the control channel input vector at the current state according to the attitude expectation value vector at the current moment and the airship attitude quantity;

[0096] The sliding mode control input calculation module T5 is used to calculate the current angular velocity sliding mode control input based on the pseudo partial derivative matrix estimate, the sliding mode surface and the sliding mode surface arrival law at the current moment;

[0097] The actual control channel input vector calculation module T6 is used to calculate the actual control channel input vector according to the control channel input vector in the historical state, the control channel input vector in the current state and the angular velocity sliding mode control input at the current moment; the actual control channel input vector is used to control the attitude of the stratospheric airship.

[0098] In an exemplary embodiment, a computer device is provided. The computer device may be a server or a terminal. The internal structure diagram thereof may be as follows: Figure 6 As shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store the model-free sliding mode control processing data of the stratospheric airship. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a model-free sliding mode control method for the stratospheric airship is implemented.

[0099] Those skilled in the art will understand that Figure 6 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0100] In an exemplary embodiment, a computer device is further provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above-mentioned method embodiments when executing the computer program.

[0101] In an exemplary embodiment, a computer-readable storage medium is provided, storing a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0102] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0103] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM may be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0104] The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. The non-relational database may include a distributed database based on blockchain, etc., but is not limited thereto. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but is not limited thereto.

[0105] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0106] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A model-free sliding mode control method for a stratospheric airship, characterized in that: The stratospheric airship model-free sliding mode control method comprises: Establish a stratospheric airship attitude control model for the target airship; Based on the stratospheric airship attitude control model, calculating the estimated value of the pseudo partial derivative matrix at the current moment; Calculate the angular velocity control input vector at the current moment according to the angular velocity control input vector at the previous moment, the attitude expected value vector at the next moment, the attitude value of the airship at the current moment, and the pseudo partial derivative matrix of the control system; Based on the forgetting factor mechanism, the control channel input vector of the historical state is calculated according to the angular velocity control input vector at the initial moment, the attitude expectation value vector at each historical moment in the historical period, and the airship attitude quantity; the control channel input vector of the current state is calculated according to the attitude expectation value vector at the current moment and the airship attitude quantity; Calculate the current angular velocity sliding mode control input based on the estimated value of the pseudo partial derivative matrix, the sliding mode surface and the sliding mode surface arrival law; According to the control channel input vector in the historical state, the control channel input vector in the current state and the angular velocity sliding mode control input at the current moment, an actual control channel input vector is calculated; the actual control channel input vector is used to control the attitude of the stratospheric airship.

2. The stratospheric airship model-free sliding mode control method according to claim 1, characterized in that: According to the control channel input vector of the historical state, the control channel input vector of the current state and the angular velocity sliding mode control input at the current moment, the actual control channel input vector is calculated, specifically including: Calculate the current angular velocity model-free control input based on the control channel input vector of the historical state and the control channel input vector of the current state; The actual control channel input vector is obtained by performing weighted summation on the current angular velocity model-free control input and the current angular velocity sliding mode control input.

3. The model-free sliding mode control method for stratospheric airship according to claim 2, characterized in that: The calculation formula of the model-free control input of the angular velocity at the current moment is as follows: Among them, τ ωMFA (k) is the model-free control input of the angular velocity at the current time k, is the forgetting factor at time n-1, τ ω (0) is the angular velocity control input vector at the initial moment, is the forgetting factor of the historical moment i, i = 1, 2, 3...n-1; λ and ρ are design parameters, Ω * (i+1) represents the expected value vector of the attitude at the next moment of the historical time i, Ω(i) represents the attitude of the airship at the historical time i, Ω * (n+1) represents the attitude expectation value vector at time n+1, and Ω(n) represents the airship attitude value at time n.

4. The stratospheric airship model-free sliding mode control method according to claim 2, characterized in that: The calculation formula of the actual control channel input vector is as follows: t ω (k)=τ ωMFA (k)+Γτ ωSM (k); Among them, τ ω (k) is the actual control channel input vector at the current time k, τ ωMFA (k) is the angular velocity model-free control input at the current time k, Γ is the diagonal weight vector, τ ωSM (k) is the sliding mode control input at the current moment k.

5. The model-free sliding mode control method for stratospheric airship according to claim 1, characterized in that: The current angular velocity sliding mode control input is calculated based on the estimated value of the pseudo partial derivative matrix, the sliding mode surface and the sliding mode surface arrival law at the current moment, specifically including: Calculate the attitude tracking error based on the attitude expected value vector and the airship attitude quantity at the current moment; Define the sliding surface according to the posture tracking error; The angular velocity sliding mode control input at the current moment is calculated according to the estimated value of the pseudo partial derivative matrix at the current moment, the sliding surface and the sliding surface arrival law.

6. The model-free sliding mode control method for stratospheric airship according to claim 5, characterized in that: The calculation formula of the angular velocity sliding mode control input at the current moment is as follows: τ ωSM(k) =θ c (k) -1 [Ω * (k+1)-Ω(k)-(1-qT)s(k)+εTsign(s(k))]; Among them, τ ωSM (k) is the sliding mode control input at the current moment k, is the estimated value of the pseudo partial derivative matrix at the current moment k, Ω * (k+1) represents the attitude expectation vector of the next moment of the current moment k, Ω(k) represents the attitude of the airship at the current moment k, q and ε are design parameters, T is the sampling time, s(k) is the sliding surface state at the current moment k, and sign is the sign function.

7. The model-free sliding mode control method for stratospheric airship according to claim 5, characterized in that: The expression of the sliding surface arrival law is as follows: s(k+1)-s(k)=-qTs(k)-εTsign(s(k)); Among them, s(k+1) is the sliding surface state at the next moment of the current moment k, s(k) is the sliding surface state at the current moment k, q and ε are design parameters, T is the sampling time, and sign is the sign function.

8. A model-free sliding mode control device for a stratospheric airship, characterized in that: The stratospheric airship model-free sliding mode control device comprises: A stratospheric airship attitude control model building module is used to: build a stratospheric airship attitude control model of a target airship; A pseudo partial derivative matrix estimation value calculation module is used to calculate the pseudo partial derivative matrix estimation value at the current moment based on the stratospheric airship attitude control model; The angular velocity control input vector calculation module is used to calculate the angular velocity control input vector at the current moment according to the angular velocity control input vector at the previous moment, the attitude expected value vector at the next moment, the attitude value of the airship at the current moment, and the pseudo partial derivative matrix of the control system; The control channel input vector calculation module is used to: calculate the control channel input vector of the historical state based on the forgetting factor mechanism according to the angular velocity control input vector at the initial moment, the attitude expectation value vector at each historical moment in the historical period, and the airship attitude quantity; calculate the control channel input vector at the current state according to the attitude expectation value vector at the current moment and the airship attitude quantity; The sliding mode control input calculation module is used to calculate the current angular velocity sliding mode control input based on the pseudo partial derivative matrix estimation value, the sliding mode surface and the sliding mode surface arrival law at the current moment; The actual control channel input vector calculation module is used to calculate the actual control channel input vector according to the control channel input vector in the historical state, the control channel input vector in the current state and the angular velocity sliding mode control input at the current moment; the actual control channel input vector is used to control the attitude of the stratospheric airship.

9. A computer device comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the model-free sliding mode control method for a stratospheric airship according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the model-free sliding mode control method for a stratospheric airship according to any one of claims 1 to 7 is implemented.

Images