Self-adaptive control method and system for coping with bilateral network attack

Abstract

The invention discloses a self-adaptive control method of a switching information physical system under the condition of coping with bilateral network attacks, and designs a self-adaptive controller, a correction signal, a self-adaptive law and an average residence time switching law in order to reduce the influence of the bilateral network attacks on the system performance. The switching information physical system which is attacked by the network from the sensor to the controller end and the network from the controller to the actuator end is gradually converged to zero, and the problem of self-adaptive control is solved. According to the method, bilateral network attacks can be effectively handled, the performance of the switching information physical system subjected to the network attacks is improved, and the safety of the switching information physical system is improved.

Description

Technical Field

[0001] The present invention relates to the field of security control technology for switching information-physical systems, and in particular to an adaptive control method and system for coping with bilateral network attacks. Background Art

[0002] With the rapid development of the Internet, the application scope of switching cyber-physical systems is becoming wider and wider. Since switching cyber-physical systems contain a network layer, they are vulnerable to network attacks, and most of them are bilateral network attacks, that is, the sensor-to-controller network and the controller-to-actuator network in the switching cyber-physical system are attacked at the same time.

[0003] Cyber ​​attacks will greatly affect the stable operation of the switching information-physical system and have a serious impact on the production activities of the actual physical layer. This makes it an urgent problem to ensure the smooth operation of the switching information-physical system under attack.

[0004] Switching systems have powerful approximation capabilities, and now more and more practical applications are described in the form of switching systems. As the foundation of Industry 4.0, cyber-physical systems have been widely used in many fields, such as smart grids and smart healthcare. Modeling cyber-physical systems as switching cyber-physical systems gives them a wider range of applications. Switching cyber-physical systems include network layers and physical layers. The network layer is often attacked by the network, which in turn affects the performance of the physical layer and causes losses to the physical world. Adaptive control can adjust the controller so that the control system can maintain or reach the desired performance level when the parameters of the controlled system are unknown or time-varying. Therefore, when the switching cyber-physical system is attacked by the network and generates uncertain parameters, adaptive control can adjust the controller to keep the system performance stable. By analyzing the performance of the system, the system's ability to cope with interference and attacks is ultimately guaranteed. Summary of the invention The object of the present invention is to provide an adaptive control method for a switching cyber-physical system under a bilateral network attack.

[0006] To achieve the above object, the present invention proposes an adaptive control method for coping with bilateral network attacks, comprising: 1) Establish a dynamic model of a switched cyber-physical system that is attacked by a cyber attack. The cyber attack simultaneously attacks the sensor-to-controller network and the controller-to-actuator network in the switched cyber-physical system. 2) Design correction signals and adaptive laws that switch cyber-physical systems after being attacked by a cyber attack; 3) Design an adaptive controller under network attack based on the correction signal and the adaptive law; 4) Design the average dwell time switching law to ensure the asymptotic convergence of the closed-loop system.

[0007] In step 1, the dynamic model of the switching cyber-physical system is: , in, is the state vector of the switched cyber-physical system, is the control input, To control the output, is the external disturbance, is an n-dimensional vector space, for p dimensional vector space, for q dimensional vector space, for r dimensional vector space, n, p, q, r belongs to the set of natural numbers N; is the switching law, which is a piecewise constant function whose value is taken from a finite set ,in Representing the number of subsystems, the switching sequence is described in the following form: , in is a set of {0,1,2,…}, when At that time, subsystem is activated, for any ,matrix , , , and are all known constant matrices with corresponding dimensions.

[0008] In addition, in step 1, the cyber attack acts on the state of the switching cyber-physical system and the cyber attack acts on the controller as follows: , in, and The attacks are on the sensor-to-controller network and the controller-to-actuator network, respectively, and meet the following conditions: , in, is an unknown time-varying weight and satisfies , are two normal numbers, are unknown and time-varying matrix weights, is a nonlinear function, and for m dimensional vector space.

[0009] In step 2, the designed correction signal is in the following form: , The designed adaptive law has the following form: , in is a vector function of hyperbolic tangent functions, is a n dimensional column vector, are four positive scalars, is the controller gain matrix, is a positive definite matrix, Proj is a projection operator, which is defined as follows: , in , is the bound of the projection operator, is a positive constant, and , and obtain the following relationship: .

[0010] In step 3, the adaptive controller under network attack is designed according to the correction signal and the adaptive law: , in, is an unknown but bounded function, ,in is a normal number, It is an unknown nonlinear function of the state under the influence of the attack.

[0011] In step 4, the average dwell time switching law is designed as: , in, Indicates the dwell time, and are two given constants greater than zero, The closed-loop system model is established as: , And the closed-loop system meets the following conditions: 1) Disturbance When , the closed-loop system state converges to zero; 2) When the disturbance When it is not zero, the system output The following inequality is satisfied: , in c is dependent on the adaptive parameters , , The constant, are two constants greater than zero.

[0012] The present invention also provides a system for dealing with bilateral network attacks, comprising: A model building module for building a dynamic model of a switching cyber-physical system under cyber attack; The control building module is used to design the correction signal and adaptive law for switching the information-physical system after being attacked by a network, and to design an adaptive controller under the network attack state based on the correction signal and the adaptive law, and to design the average residence time switching law to ensure the asymptotic convergence of the closed-loop system.

[0013] The present invention also provides a device for coping with bilateral network attacks, comprising a processor and a memory, wherein when the processor executes a computer program stored in the memory, the adaptive control method for coping with bilateral network attacks as described above is implemented.

[0014] The present invention also provides a computer-readable storage medium for storing a computer program, wherein the computer program, when executed by a processor, implements the above-mentioned adaptive control method for coping with bilateral network attacks.

[0015] Compared with the prior art, the present invention has the following beneficial effects: the present invention models the cyber-physical system as a switching cyber-physical system; considers the situation where the sensor-to-controller and controller-to-actuator dual-end networks of the switching cyber-physical system are simultaneously attacked by the network; and adopts an adaptive control method to ensure the performance of the closed-loop system on the basis of the asymptotic convergence of the closed-loop system. The present invention provides an adaptive control method for the switching cyber-physical system under bilateral network attacks, improves the system's ability to cope with attacks and disturbances, effectively ensures the smooth operation of the system, and improves the security of the switching cyber-physical system. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 It is a schematic diagram of the process of the present invention; Figure 2 It is a trajectory diagram for the controller in the embodiment; Figure 3 It is the state response trajectory in the embodiment; Figure 4 Output trajectory diagram in the embodiment. DETAILED DESCRIPTION The specific embodiments of the present invention are described in detail below, but it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

[0018] Unless explicitly stated otherwise, throughout the specification and claims, the term “comprise” or variations such as “include” or “comprising” will be understood to include the stated elements or components but not to exclude other elements or components.

[0019] like Figure 1 As shown, the present invention discloses an adaptive control method for coping with bilateral network attacks, comprising the following steps: 1) A dynamic model of a switched cyber-physical system under cyber attack is established. The cyber attack simultaneously attacks the sensor-to-controller network and the controller-to-actuator network in the switched cyber-physical system.

[0020] The dynamic model of the switching cyber-physical system is: , in, is the state vector of the switched cyber-physical system, is the control input, To control the output, is the external disturbance, is an n-dimensional vector space, for p dimensional vector space, for q dimensional vector space, for r dimensional vector space, n, p, q, r belongs to the set of natural numbers N; is the switching law, which is a piecewise constant function whose value is taken from a finite set ,in Representing the number of subsystems, the switching sequence is described in the following form: , in is a set of {0,1,2,…}, when At that time, subsystem is activated, for any ,matrix , , , and are all known constant matrices with corresponding dimensions.

[0021] , , , , , , , , , .

[0022] In addition, the cyber attack acts on the state of the switching cyber-physical system and the cyber attack acts on the controller as follows: , in, and The attacks are on the sensor-to-controller network and the controller-to-actuator network, respectively, and meet the following conditions: , in, is an unknown time-varying weight and satisfies , are two normal numbers, are unknown and time-varying matrix weights, is a nonlinear function, and for m dimensional vector space.

[0023] 2) Design correction signals and adaptive laws that switch the cyber-physical system after being attacked by a cyber attack.

[0024] Among them, the designed correction signal is in the following form: , The designed adaptive law has the following form: , in is a vector function of hyperbolic tangent functions, is a n dimensional column vector, are four positive scalars, is the controller gain matrix, is a positive definite matrix, Proj is a projection operator, which is defined as follows: , in , is the bound of the projection operator, is a positive constant, and , and obtain the following relationship: .

[0025] 3) Design an adaptive controller under network attack based on the correction signal and the adaptive law.

[0026] Specifically: , in, is an unknown but bounded function, ,in is a normal number, is an unknown nonlinear function of the state under the influence of the attack. The final solution of the controller gain is: , .

[0027] The controller implements the trajectory as Figure 2 shown.

[0028] 4) Design the average dwell time switching law to ensure the asymptotic convergence of the closed-loop system.

[0029] Specifically, the average residence time switching law is designed as: , in, , ,Pick .

[0030] The closed-loop system model is established as: , in, .

[0031] And the closed-loop system meets the following conditions: 1) Disturbance When , the closed-loop system state converges to zero; 2) When the disturbance When it is not zero, the system output The following inequality is satisfied: , in c is dependent on the adaptive parameters , , The constant, are two constants greater than zero, , .

[0032] Select the switching sequence as 1→2→1→2…, and the state response trajectory is as follows Figure 3 As shown, the output trajectory is Figure 4 shown.

[0033] The present invention also provides a system for dealing with bilateral network attacks, comprising: A model building module for building a dynamic model of a switching cyber-physical system under cyber attack; The control building module is used to design the correction signal and adaptive law for switching the information-physical system after being attacked by a network, and to design an adaptive controller under the network attack state based on the correction signal and the adaptive law, and to design the average residence time switching law to ensure the asymptotic convergence of the closed-loop system.

[0034] The present invention also provides a device for coping with bilateral network attacks, comprising a processor and a memory, wherein when the processor executes a computer program stored in the memory, the adaptive control method for coping with bilateral network attacks as described above is implemented.

[0035] The present invention also provides a computer-readable storage medium for storing a computer program, wherein the computer program, when executed by a processor, implements the above-mentioned adaptive control method for coping with bilateral network attacks.

[0036] The advantages of the present invention are that the present invention models the cyber-physical system as a switching cyber-physical system; considers the situation where the sensor-to-controller and controller-to-actuator dual-end networks of the switching cyber-physical system are simultaneously attacked by the network; and adopts an adaptive control method to ensure the performance of the closed-loop system on the basis of the asymptotic convergence of the closed-loop system. The present invention provides an adaptive control method for the switching cyber-physical system under bilateral network attack, improves the system's ability to cope with attacks and disturbances, effectively ensures the smooth operation of the system, and improves the security of the switching cyber-physical system.

[0037] It should be noted that the contents not described in detail in the specification of the present invention belong to the prior art known to professional and technical personnel in the field.

[0038] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. An adaptive control method for dealing with bilateral network attacks, the characteristics of which include: 1) Establish a dynamic model of a switched cyber-physical system that is attacked by a cyber attack. The cyber attack simultaneously attacks the sensor-to-controller network and the controller-to-actuator network in the switched cyber-physical system. 2) Design correction signals and adaptive laws that switch cyber-physical systems after being attacked by a cyber attack; 3) Design an adaptive controller under network attack based on the correction signal and the adaptive law; 4) Design the average dwell time switching law to ensure the asymptotic convergence of the closed-loop system.

2. The adaptive control method for coping with bilateral network attacks according to claim 1, characterized in that: In step 1, the dynamic model of the switching cyber-physical system is: ， in, is the state vector of the switched cyber-physical system, is the control input, To control the output, is the external disturbance, is an n-dimensional vector space, for p dimensional vector space, for q dimensional vector space, for r dimensional vector space, n, p, q, r belongs to the set of natural numbers N; is the switching law, which is a piecewise constant function whose value is taken from a finite set ,in Representing the number of subsystems, the switching sequence is described in the following form: ， in is a set of {0,1,2,…}, when At that time, subsystem is activated, for any ,matrix , , , and are all known constant matrices with corresponding dimensions.

3. The adaptive control method for coping with bilateral network attacks according to claim 2, characterized in that: In step 1, the cyber attack acts on the state of the switching cyber-physical system and the cyber attack acts on the controller as follows: ， in, and The attacks are on the sensor-to-controller network and the controller-to-actuator network, respectively, and meet the following conditions: ， in, is an unknown time-varying weight and satisfies , are two normal numbers, are unknown and time-varying matrix weights, is a nonlinear function, and for m dimensional vector space.

4. The adaptive control method for coping with bilateral network attacks according to claim 3, characterized in that: In step 2, the designed correction signal is in the following form: ， The designed adaptive law has the following form: ， in is a vector function of hyperbolic tangent functions, is a n dimensional column vector, are four positive scalars, is the controller gain matrix, is a positive definite matrix, Proj is a projection operator, which is defined as follows: ， in , is the bound of the projection operator, is a positive constant, and , and obtain the following relationship: 。 5. The adaptive control method for coping with bilateral network attacks according to claim 4, characterized in that: In step 3, the adaptive controller designed according to the correction signal and the adaptive law under the network attack state is: ， in, is an unknown but bounded function, ,in is a normal number, It is an unknown nonlinear function of the state under the influence of the attack.

6. The adaptive control method for coping with bilateral network attacks according to claim 5, characterized in that: In step 4, the average dwell time switching law is designed as: ， in, Indicates the dwell time, and are two given constants greater than zero, The closed-loop system model is established as: 。 7. The adaptive control method for coping with bilateral network attacks according to claim 6, characterized in that: The closed-loop system meets the following conditions: 1) Disturbance When , the closed-loop system state converges to zero; 2) When the disturbance When it is not zero, the system output The following inequality is satisfied: ， in c is dependent on the adaptive parameters , , The constant, are two constants greater than zero.

8. A system for dealing with bilateral network attacks, characterized in that: include: A model building module for building a dynamic model of a switching cyber-physical system under cyber attack; The control building module is used to design the correction signal and adaptive law for switching the information-physical system after being attacked by a network, and to design an adaptive controller under the network attack state based on the correction signal and the adaptive law, and to design the average residence time switching law to ensure the asymptotic convergence of the closed-loop system.

9. A device for dealing with bilateral network attacks, characterized in that: The method comprises a processor and a memory, wherein when the processor executes the computer program stored in the memory, the method realizes the adaptive control method for coping with bilateral network attacks as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: Used to store a computer program, wherein when the computer program is executed by a processor, the adaptive control method for coping with a bilateral network attack according to any one of claims 1 to 7 is implemented.

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