Fault location and fault-tolerant method of master-slave cooperative guidance system in communication interference environment

Abstract

The application provides a master-slave cooperative guidance system fault positioning and fault-tolerant method in a communication interference environment. The method can effectively position and tolerate the fault of the communication link error information injection in the cooperative guidance system. First, a distributed observer is constructed according to the cooperative variable of the master-slave cooperative guidance system. Second, the consistency error and the absolute error based on the state output of the observer are calculated. Third, the self-confidence coefficient of each node of the cooperative guidance system and the trust coefficient of each node to the communication link of the neighbor node are evaluated. Finally, the fault-tolerant cooperative guidance law is given. Thus, the node fault or the communication link fault of the master-slave multi-aircraft cooperative guidance system in the communication interference environment can be effectively positioned and tolerated.

Description

Technical Field

[0001] This invention relates to a method for fault location and fault tolerance in a master-slave multi-aircraft cooperative guidance system under communication interference conditions, belonging to the field of aircraft guidance and control. Specifically, it proposes a method for fault location and fault tolerance of each node and data communication link when the inter-aircraft communication data link is hijacked and injected with erroneous decoy data under communication interference conditions. Background Technology

[0002] Cluster systems offer advantages such as efficient integration, complementary collaboration, and information sharing. However, the real-time information exchange required for collaborative control relies on data link communication networks. The security of communication links and control systems directly impacts the reliability of aircraft cluster systems. In environments with strong communication jamming denial, the communication data link of a collaborative guidance system is susceptible to interference, leading to reduced collaborative execution efficiency and, in severe cases, disruption of the entire collaborative mission execution process. Enemy jamming equipment may inject deceptive jamming signals to mislead the normal decision-making and control of the collaborative guidance system, making it difficult to guarantee system performance or, in severe cases, allowing the system to be exploited by the enemy. Deceptive jamming often employs multiple information technologies to exert interference and inducement behaviors, such as causing aircraft to receive incorrect instructions, which can easily lead to mission failure or even self-destruction due to misoperation. Therefore, it is necessary to conduct fault location and fault tolerance studies on collaborative guidance systems in communication jamming environments when deceptive erroneous information is injected, to enhance the reliability and security of multi-aircraft collaborative guidance systems. Summary of the Invention

[0003] Assuming the entire aircraft swarm consists of one master aircraft and n slave aircraft, the technical concept of this invention is as follows: when an aircraft node or communication link is injected with erroneous interference signals, the method designed in this invention can effectively locate and tolerate node faults and communication link faults in the cooperative guidance system. First, a distributed observer is constructed based on the cooperative variables of the master-slave cooperative guidance system; second, the consistency error and absolute error based on the observer's state output are calculated; third, the confidence coefficient of each node in the cooperative guidance system and the trust coefficient of each node in its communication links with its neighbors are evaluated; finally, a fault-tolerant cooperative guidance law is given. This enables effective location and fault tolerance of node faults or communication link faults in a master-slave multi-aircraft cooperative guidance system under communication interference conditions.

[0004] The fault location and fault tolerance method for a master-slave multi-aircraft cooperative guidance system under communication interference environment designed in this invention includes the following steps:

[0005] Step 1: Construct a distributed observer based on the collaborative variables of the master-slave cooperative guidance system;

[0006] Assume a swarm of aircraft consists of one master aircraft and n slave aircraft. Algebraic graph theory can be used to represent the communication relationships between the aircraft. The communication relationships between slave aircraft can be represented by an adjacency matrix A = [a...]. ij Let ] represent that if the i-th (i = 1, 2, ..., n) slave spacecraft can establish a communication relationship with the j-th (j = 1, 2, ..., n, j ≠ i) slave spacecraft, then a ij =1, otherwise, a ij =0. The master aircraft can only send information to some slave aircraft that meet the communication conditions, but cannot receive information from slave aircraft. c is used. i This represents the communication relationship between the i-th slave spacecraft and the master spacecraft. If the slave spacecraft can receive information from the master spacecraft, then c... i =1, otherwise c i =0. If there is always at least one communication path between any two aircraft nodes in a networked communication topology, then this communication topology is called a connected graph. If all information transmission in a communication topology is bidirectional, then the graph is called an undirected graph; if there is a unidirectional information transmission link, then the communication topology is called a directed graph.

[0007] The motion relationship of an aircraft in a two-dimensional plane can be expressed as:

[0008]

[0009] In the formula, r i V represents the distance between the i-th aircraft and the target. i q represents the constant velocity of the aircraft. i γ is the viewing angle. i and φ i These are the aircraft's track angle and lead angle, and the normal acceleration a. i Perpendicular to the velocity direction, the cooperative guidance law will be derived through the design normal acceleration. The variables relevant to the primary aircraft are labeled with subscript 0, and the i-th variable relevant to the secondary aircraft is labeled with subscript i, i = 1, 2, ..., n.

[0010] The master aircraft's guidance law is independently designed and unaffected by the slave aircraft. Assuming it uses improved proportional guidance, its remaining hit time during flight is... It can be calculated using the following formula:

[0011]

[0012] In the formula, r0 represents the distance between the main aircraft and the target, V0 represents the speed of the main aircraft, and N... s For navigation ratio, φ0 is the lead angle of the main aircraft.

[0013] Designing distributed observers from aircraft:

[0014]

[0015] In the formula, k1 represents a positive real number. and These represent the remaining hit times of the i-th and j-th slave aircraft to the master aircraft, respectively. The observed values.

[0016] Step 2: Calculate the consistency error and absolute error based on the observer state output;

[0017] The consistency error of remaining hit time observations is defined as:

[0018]

[0019] Define the absolute error of inconsistency between individuals as:

[0020]

[0021] Step 3: Evaluate the confidence coefficient of each node in the cooperative guidance system;

[0022] Calculate the confidence coefficient of the i-th slave aircraft:

[0023]

[0024] In the formula, ρ>0 represents a positive real number, and the self-confidence coefficient difference variable s i Defined as:

[0025]

[0026] In the formula, ε i =|e i |,Ξ i >0 is a threshold used to offset the effects of uncertainties other than communication interference.

[0027] Step 4: Evaluate the trust coefficient of each node in the cooperative guidance system for its communication links with its neighboring nodes;

[0028] Calculate the trust coefficient b between the i-th aircraft and its neighboring node aircraft j. ij for:

[0029]

[0030] In the formula, η>0 is a positive real number, and the confidence coefficient difference variable ξ ij Defined as:

[0031]

[0032] In the formula, N i Let |N| represent the set of neighbors of the i-th aircraft.i | represents the number of the i-th neighboring aircraft, Λ i This is a threshold value used to offset the effects of uncertainties beyond communication interference. This indicates the remaining hit time between the l-th slave aircraft and the master aircraft. The observed values.

[0033] Step 5: Determine the reliability of nodes and communication links by setting confidence thresholds and trust thresholds;

[0034] Set the confidence threshold of the i-th slave aircraft to C. m We can obtain:

[0035]

[0036] When the confidence judgment value f i When f = 1, the i-th slave aircraft is determined to be reliable. i When the value is 0, the i-th slave aircraft is determined to be unreliable.

[0037] Similarly, set the trust threshold to b. m We can obtain:

[0038]

[0039] When the trust judgment value T ij When T = 1, the communication link between the i-th slave spacecraft's neighbor nodes is determined to be reliable. ij When the value is 0, the communication link between the i-th slave spacecraft's neighbor nodes is determined to be unreliable.

[0040] When C m and b m When the value is too large, it can easily lead to non-interference factors, such as model uncertainty, causing the evaluation results to misclassify non-fault states as faults. When the value is too small, it may misclassify fault states as non-fault states. It is recommended to select a value between [0.5 0.9], which can generally avoid fault misclassification.

[0041] Step 6: Design fault-tolerant cooperative guidance law;

[0042] Considering confidence and trust scores, the distributed observer can be improved as follows:

[0043]

[0044] The fault-tolerant cooperative guidance law is designed as follows:

[0045]

[0046] In the formula, k2>0 is a positive real number, and N s >2 indicates the navigation ratio. The remaining hit time prediction value for the i-th aircraft can be calculated by the following formula:

[0047]

[0048] The beneficial effects of this invention are as follows: It designs a fault location and fault tolerance method based on a distributed observer, which can evaluate the confidence coefficient of each node in the cooperative guidance system, as well as the trust coefficient of the aircraft node to its neighbor node's communication link. By setting confidence thresholds and trust thresholds, the reliability of nodes and communication links is determined, and finally, a fault-tolerant cooperative guidance law is given, thereby achieving effective location and fault tolerance for node faults or communication link faults in a master-slave multi-aircraft cooperative guidance system under communication interference environments. Attached Figure Description

[0049] Figure 1 This is a diagram illustrating the communication relationships between aircraft.

[0050] Figure 2 It is the flight trajectory curve.

[0051] Figure 3 It is the distance curve between the aircraft and the target.

[0052] Figure 4 It is a confidence coefficient curve.

[0053] Figure 5 It is a trust coefficient curve.

[0054] Figure 6 It is the output response of the distributed observer.

[0055] Figure 7 It is a consistent co-variable response.

[0056] Figure 8 It is the normal acceleration response curve. Detailed Implementation

[0057] To make the objectives, technical solutions, and advantages of this invention clearer, please refer to the appendix. Figure 1 —8. Further explanation of the present invention.

[0058] The invented method for locating and tolerating faults in the communication data link of a master-slave multi-aircraft cooperative guidance system under communication interference environments includes the following steps:

[0059] Step 1: Construct a distributed observer based on the collaborative variables of the master-slave cooperative guidance system;

[0060] Assume a swarm of aircraft consists of one master aircraft and n slave aircraft. Algebraic graph theory can be used to represent the communication relationships between the aircraft. The communication relationships between slave aircraft can be represented by an adjacency matrix A = [a...]. ijLet ] represent that if the i-th (i = 1, 2, ..., n) slave spacecraft can establish a communication relationship with the j-th (j = 1, 2, ..., n, j ≠ i) slave spacecraft, then a ij =1, otherwise, a ij =0. The master aircraft can only send information to some slave aircraft that meet the communication conditions, but cannot receive information from slave aircraft. c is used. i This represents the communication relationship between the i-th slave spacecraft and the master spacecraft. If the slave spacecraft can receive information from the master spacecraft, then c... i =1, otherwise c i =0. If there is always at least one communication path between any two aircraft nodes in a networked communication topology, then this communication topology is called a connected graph. If all information transmission in a communication topology is bidirectional, then the graph is called an undirected graph; if there is a unidirectional information transmission link, then the communication topology is called a directed graph.

[0061] The motion relationship of an aircraft in a two-dimensional plane can be expressed as:

[0062]

[0063] In the formula, r i V represents the distance between the i-th lead missile and the target. i q represents the constant velocity of the aircraft. i γ is the viewing angle. i and φ i These are the aircraft's track angle and lead angle, and the normal acceleration a. i Perpendicular to the velocity direction. The main aircraft-related variables are labeled with subscript 0, and the i-th slave aircraft-related variables are labeled with subscript i, i = 1, 2, ..., n.

[0064] The master aircraft's guidance law is independently designed and unaffected by the slave aircraft. Assuming it uses improved proportional guidance, its remaining hit time during flight is... It can be calculated using the following formula:

[0065]

[0066] In the formula, r0 represents the distance between the main aircraft and the target, V0 represents the speed of the main aircraft, and N... s For navigation ratio, φ0 is the lead angle of the main aircraft.

[0067] Designing distributed observers from aircraft:

[0068]

[0069] In the formula, k1 represents a positive real number. and These represent the remaining hit times of the i-th and j-th slave aircraft to the master aircraft, respectively. The observed values.

[0070] Step 2: Calculate the consistency error and absolute error based on the observer state output;

[0071] The consistency error of remaining hit time observations is defined as:

[0072]

[0073] Define the absolute error of inconsistency between individuals as:

[0074]

[0075] Step 3: Evaluate the confidence coefficient of each node in the cooperative guidance system;

[0076] Calculate the confidence coefficient of the i-th slave aircraft:

[0077]

[0078] In the formula, ρ>0 represents a positive real number, and the self-confidence coefficient difference variable s i Defined as:

[0079]

[0080] In the formula, ε i =|e i |,Ξ i >0 is a threshold used to offset the effects of uncertainties other than communication interference.

[0081] Step 4: Evaluate the trust coefficient of each node in the cooperative guidance system for its communication links with its neighboring nodes;

[0082] The trust coefficient of the i-th aircraft with its neighboring aircraft j is calculated as follows:

[0083]

[0084] In the formula, η>0 is a positive real number, and the confidence coefficient difference variable ξ ij Defined as:

[0085]

[0086] In the formula, N i Let |N| represent the set of neighbors of the i-th aircraft. i | represents the number of the i-th neighboring aircraft, Λ i This is a threshold value used to offset the effects of uncertainties beyond communication interference. This indicates the remaining hit time between the l-th slave aircraft and the master aircraft. The observed values.

[0087] Step 5: Determine the reliability of nodes and communication links by setting confidence thresholds and trust thresholds;

[0088] Set the confidence threshold of the i-th slave aircraft to C. m We can obtain:

[0089]

[0090] When the confidence judgment value f i When f = 1, the i-th slave aircraft is determined to be reliable. i When the value is 0, the i-th slave aircraft is determined to be unreliable.

[0091] Similarly, set the trust threshold to b. m We can obtain:

[0092]

[0093] When the trust judgment value T ij When T = 1, the communication link between the i-th slave spacecraft's neighbor nodes is determined to be reliable. ij When the value is 0, the communication link between the i-th slave spacecraft's neighbor nodes is determined to be unreliable.

[0094] When C m and b m When the value is too large, it can easily lead to non-interference factors, such as model uncertainty, causing the evaluation results to misclassify non-fault states as faults. When the value is too small, it may misclassify fault states as non-fault states. It is recommended to select a value between [0.5 0.9], which can generally avoid fault misclassification.

[0095] Step 6: Design fault-tolerant cooperative guidance law;

[0096] Considering confidence and trust scores, the distributed observer can be improved as follows:

[0097]

[0098] The fault-tolerant cooperative guidance law is designed as follows:

[0099]

[0100] In the formula, k2>0 is a positive real number, and N s >2 indicates the navigation ratio. The remaining hit time prediction value for the i-th aircraft can be calculated by the following formula:

[0101]

[0102] The Matlab / Simulink simulation platform was used to verify the fault location and evaluation method of the designed master-slave cooperative guidance system under communication interference environment. For the example, one master aircraft and three slave aircraft were selected, with a normal inter-missile communication topology as follows: Figure 1 As shown in (a), an erroneous data injection failure occurs at 5s, and the communication topology changes. Figure 1 As shown in (b), the data transmitted from aircraft 2 to aircraft 1 and 3 is respectively altered to random signals with d(t) = 200sin(50t) and a maximum amplitude of 100. The target position is (12000m, 10000m), the speed of the master aircraft V0 is 200m / s, and the initial speeds of the slave aircraft are V1 = 300m / s, V2 = 300m / s, and V3 = 300m / s. The initial position of the master aircraft is (1000m, 5000m), and the initial positions of the slave aircraft are (3000m, 4000m), (5000m, 3000m), and (6000m, 2000m) respectively. The overload limit of the aircraft is 20g.

[0103] Simulation results are as follows Figures 2-8 As shown, the flight trajectory curve Figure 2 Distance curve between aircraft and target Figure 3 It can be seen that, under the invented fault location and evaluation method for the master-slave cooperative guidance system, all aircraft can ultimately reach the target simultaneously as expected. Before the fault occurs, the consistency coordination error can converge stably, and the observer output value can accurately track the expected value. When an erroneous data injection fault occurs in the communication link, Figure 4 The confidence coefficients C1 and C3 of aircraft 1 and aircraft 3 decreased significantly due to the influence of erroneous data. Figure 5 Trust coefficient b 12 and b 32 The error rate drops to 0, thus cutting off the erroneous data injection link. Subsequently, the confidence coefficients C1 and C3 rebound. Figure 6 The observer output response, Figure 7 Inconsistent cooperative error curve and Figure 8 After a brief distortion, the acceleration response in the medium- and normal directions returns to normal through fault-tolerant adjustment. Simulation results verify that the designed method can effectively suppress the destructive impact of communication data link error data injection interference on the cooperative guidance system.

Claims

1. A fault location and fault tolerance method for a master-slave cooperative guidance system under communication interference environment, characterized in that, Includes the following steps: Step 1: Construct a distributed observer based on the collaborative variables of the master-slave cooperative guidance system; Step 2: Calculate the consistency error and absolute error based on the observer state output; Step 3: Evaluate the confidence coefficient of each node in the cooperative guidance system; Step 4: Evaluate the trust coefficient of each node in the cooperative guidance system for its communication links with its neighboring nodes; Step 5: Determine the reliability of nodes and communication links by setting confidence thresholds and trust thresholds; Step 6: Design fault-tolerant cooperative guidance law; In step 6, considering the confidence judgment value and the trust judgment value, the distributed observer is improved as follows: The fault-tolerant cooperative guidance law is designed as follows: In the formula, k2>0 is a positive real number, and N s >2 indicates the navigation ratio. The remaining hit time prediction value for the i-th aircraft is calculated by the following formula:

2. The fault location and fault tolerance method for a master-slave cooperative guidance system under communication interference environment according to claim 1, characterized in that: In step 1, each aircraft group is assumed to contain 1 master aircraft and n slave aircraft; algebraic graph theory is used to represent the communication relationships between aircraft; the communication relationships between slave aircraft are represented by the adjacency matrix A = [a ij Let ] represent that if the i-th slave spacecraft can establish a communication relationship with the j-th slave spacecraft, then a ij =1, otherwise, a ij =0.

3. The fault location and fault tolerance method for a master-slave cooperative guidance system under communication interference environment according to claim 1, characterized in that: The master aircraft only sends information to some slave aircraft that meet the communication requirements, but cannot receive information from slave aircraft. This is achieved using C. i This represents the communication relationship between the i-th slave spacecraft and the master spacecraft. If information is received from the master spacecraft, then c... i =1, otherwise c i =0.

4. The fault location and fault tolerance method for a master-slave cooperative guidance system under communication interference environment according to claim 1, characterized in that: The motion relationship of an aircraft in a two-dimensional plane can be represented as follows: In the formula, r i V represents the distance between the i-th aircraft and the target. i q represents the constant velocity of the aircraft. i γ is the viewing angle. i and φ i These are the aircraft's track angle and lead angle, and the normal acceleration a. i Perpendicular to the velocity direction, the cooperative guidance law will be given by designing the normal acceleration; the relevant variables of the main aircraft are labeled with subscript 0, and the relevant variables of the i-th slave aircraft are labeled with subscript i, i = 1, 2, ..., n.

5. The fault location and fault tolerance method for a master-slave cooperative guidance system under communication interference environment according to claim 1, characterized in that: The master aircraft's guidance law is independently designed and unaffected by the slave aircraft. Assuming it uses improved proportional guidance, the remaining hit time during flight is... It is calculated by the following formula: In the formula, r0 represents the distance between the main aircraft and the target, V0 represents the speed of the main aircraft, and N... s For navigation ratio, φ0 is the lead angle of the primary aircraft; Designing distributed observers from aircraft: In the formula, k1 represents a positive real number. and These represent the remaining hit times of the i-th and j-th slave aircraft to the master aircraft, respectively. The observed values.

6. The fault location and fault tolerance method for a master-slave cooperative guidance system under communication interference environment according to claim 1, characterized in that: In step 2, the consistency error of the remaining hit time observations is defined as: Define the absolute error of inconsistency between individuals as:

7. The fault location and fault tolerance method for a master-slave cooperative guidance system under communication interference environment according to claim 1, characterized in that: In step 3, calculate the confidence coefficient of the i-th slave aircraft: In the formula, ρ>0 represents a positive real number, and the self-confidence coefficient difference variable s i Defined as: In the formula, ε i =|e i |,Ξ i >0 is a threshold used to offset the effects of uncertainties other than communication interference.

8. The fault location and fault tolerance method for a master-slave cooperative guidance system under communication interference environment according to claim 1, characterized in that: In step 4, the trust coefficient b of the i-th aircraft to its neighboring node aircraft j is calculated. ij for: In the formula, η>0 is a positive real number, and the confidence coefficient difference variable ξ ij Defined as: In the formula, N i Let |N| represent the set of neighbors of the i-th aircraft. i | represents the number of the i-th neighboring aircraft, Λ i This is a threshold value used to offset the effects of uncertainties beyond communication interference. This indicates the remaining hit time between the l-th slave aircraft and the master aircraft. The observed values.

9. The fault location and fault tolerance method for a master-slave cooperative guidance system under communication interference environment according to claim 1, characterized in that: In step 5, the confidence threshold of the i-th slave aircraft is set to C. m ,get: When the confidence judgment value f i When f = 1, the i-th slave aircraft is determined to be reliable. i When the value is 0, the i-th slave aircraft is deemed unreliable; Set the trust threshold to b m ,get: When the trust judgment value T ij When T = 1, the communication link between the i-th slave spacecraft's neighbor nodes is determined to be reliable. ij When the value is 0, the communication link between the i-th slave spacecraft's neighbor nodes is determined to be unreliable.

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