A method and system for constructing a three-dimensional health assessment index system for an IMA system

Abstract

The present invention discloses a method and system for constructing a three-dimensional health evaluation index system of an IMA system. The hardware health index is determined according to the failure factors of IMA hardware resources, the functional health index is determined by selecting IMA functional operation monitoring parameters, and the network health index is determined by analyzing the performance status of the IMA airborne network, thereby forming a three-dimensional health index of the IMA system, and then determining the health status of the IMA system. The method analyzes the factors affecting the health status of the system from the hardware resource level, the functional operation level, and the network performance level, and constructs a system health index calculation method by acquiring information parameters related to hardware resources, functional operation, and airborne network, thereby obtaining a comprehensive system health status, accurately characterizing the ability of the IMA system to complete the current flight mission. The present invention improves the reliability and safety of the IMA system and completes the all-round monitoring of the health status of the IMA system.

Description

Technical Field

[0001] The present invention relates to the fields of aircraft avionics and health management technology, and in particular to a method for constructing a three-dimensional health assessment index system of an IMA system. Background Art

[0002] Integrated Modular Avionics (IMA) is an open hardware platform that hosts various avionics equipment functions and is one of the most important systems to ensure flight safety. In order to ensure that the aircraft can complete its flight mission safely, it is imperative to develop health management technology for IMA. At present, in the research on health management technology at home and abroad, both degradation process modeling and life prediction rely on the construction of an accurate comprehensive health assessment indicator system.

[0003] At present, the research on the construction of health assessment indicator system mainly focuses on monitoring all components or functions of the system one by one. For the highly complex and integrated IMA system, this will cause serious waste of resources and cost burden. In contrast, the IMA system can evaluate the comprehensive health status of the current IMA system by obtaining the underlying hardware resources, functional operation and airborne network performance data.

[0004] In terms of hardware resources, since multiple functions of IMA reside on the same computing platform and rely on the same hardware resources, when a hardware resource fails, all functions using the resource will be affected to varying degrees, causing defects to spread. At the functional operation level, IMA coordinates multiple functions to complete flight missions together. The failure of any function will cause errors in cross-linking. Functions exist in the form of software resources. Due to the standardized development of software and the reuse of basic programs between software, errors in basic programs will cause errors in related functions that call the program. At the network performance level, the airborne network is a means of connecting equipment, modules and components within the aircraft platform. Due to the long-term service and use of IMA, the reliability of the airborne network has declined, resulting in IMA being unable to meet the needs of flight missions. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides a method for constructing a three-dimensional health assessment index system for an IMA system, analyzes the factors affecting the health status of the system from the hardware resource level, functional operation level, and network performance level, and establishes a comprehensive health assessment system for the IMA system, thereby improving the efficiency of IMA health management.

[0006] The present invention is achieved through the following technical solutions:

[0007] A method for constructing a three-dimensional health assessment index system of an IMA system comprises the following steps:

[0008] Step 1: Determine the reliability of the hardware resources under the failure factors according to the failure factors of the IMA hardware resources, and determine the hardware health index according to the reliability;

[0009] Step 2: Obtain the memory usage abnormal status index of each functional module of IMA, then calculate the memory usage abnormal index according to the function importance, and use the calculation result as the function health index;

[0010] Step 3: Clustering the characterization parameters of the airborne network performance status into multiple levels according to the threshold, and assigning weights to the levels of each characterization parameter to obtain a network health index;

[0011] Step 4: Determine the health status of the IMA system based on the hardware health index, the functional health index, and the network health index.

[0012] Preferably, the failure factors of the IMA hardware resources in step 1 include electromigration, time-dependent dielectric breakdown and hot carrier injection.

[0013] Preferably, the method for determining the hardware health index in step 1 is as follows:

[0014] The reliability of hardware resources under failure factors is calculated according to the probability density function corresponding to the failure factors. The reliability of hardware resources under failure factors is assigned weights using an adaptive weighted average method to determine the hardware health index.

[0015] Preferably, the electromigration and hot carrier injection obey lognormal distribution, and the time-dependent dielectric breakdown obeys Weibull distribution;

[0016] The probability density function of the lognormal distribution is as follows:

[0017]

[0018] Where t represents the failure time of hardware resources, σ represents the standard deviation of the failure time of hardware resources, and μ represents the mean failure time of hardware resources;

[0019] The probability density function of the Weibull distribution is as follows:

[0020]

[0021] Among them, t represents the hardware resource failure time, α represents the feature failure time, and β represents the shape parameter.

[0022] Preferably, the reliability of the hardware resources is calculated as follows:

[0023]

[0024] Preferably, in step 2, the IMA system memory usage abnormality index Iml The expression is as follows:

[0025]

[0026] Among them, x+y+z=n is the total number of functions of the IMA system.

[0027] Preferably, the characterizing parameters of the airborne network performance status in step 3 include data transmission rate, delay and bit error rate.

[0028] Preferably, the method for dividing the characterization parameters in step 3 is as follows:

[0029]

[0030] in, It is cluster C i The mean vector of .

[0031] Preferably, in step 4, a weighted average calculation is performed on the hardware health index, the functional health index and the network health index to obtain the IMA system health index, thereby determining the IMA system health status.

[0032] A system for constructing a three-dimensional health assessment index system of an IMA system, comprising:

[0033] The hardware health index module is used to determine the reliability of the hardware resources under the failure factors according to the failure factors of the IMA hardware resources, and determine the hardware health index according to the reliability;

[0034] Functional health index module, used to obtain the memory usage abnormal status index of each functional module of IMA, and then calculate the memory usage abnormal index according to the function importance, and use the calculation result as the functional health index;

[0035] A network health index module is used to classify the characterization parameters of the airborne network performance status into multiple levels through clustering according to the threshold, and assign weights to each characterization parameter according to the divided levels to obtain the network health index;

[0036] The system health status module is used to calculate the IMA system health index by weighted average according to the hardware health index, the functional health index and the network health index, so as to determine the IMA system health status.

[0037] Compared with the prior art, the present invention has the following beneficial technical effects:

[0038] The present invention provides a method for constructing a three-dimensional health evaluation index system of an MA system, which determines the hardware health index according to the failure factors of IMA hardware resources, selects the IMA function operation monitoring parameters to determine the function health index, and analyzes the IMA airborne network performance status to determine the network health index, thereby forming a three-dimensional health index of the IMA system, and then determining the health status of the IMA system. The method analyzes the factors affecting the health status of the system from the hardware resource level, the function operation level, and the network performance level, and constructs a system health index calculation method by acquiring information parameters related to hardware resources, function operation, and airborne network, thereby obtaining a comprehensive system health status, accurately characterizing the ability of the IMA system to complete the current flight mission. The present invention improves the reliability and safety of the IMA system and completes the all-round monitoring of the health status of the IMA system. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is an overall flow chart of an embodiment of a method for constructing a three-dimensional health assessment index system of an IMA system of the present invention;

[0040] Figure 2 The hardware health index calculation method of the present invention;

[0041] Figure 3 The functional health index calculation method of the present invention;

[0042] Figure 4 The invention provides a method for constructing a network health index. DETAILED DESCRIPTION

[0043] The present invention will be further described in detail below in conjunction with the accompanying drawings, which are intended to explain the present invention rather than to limit it.

[0044] See also Figure 1-4 , a method for constructing a three-dimensional health assessment index system of an IMA system, comprising the following steps:

[0045] Step 1: Based on the IMA hardware resource failure factors.

[0046] Specifically, the failure factors of IMA hardware resources are analyzed. During the service of the aircraft, the operating status changes of hardware resources are mostly caused by mechanical failures, and more than 40% of the failures are caused by avionics system failures. Numerous studies have shown that electromigration, time-dependent dielectric breakdown, and hot carrier injection are three common failure factors in electronic circuits that lead to performance degradation.

[0047] Step 2: Construct a hardware health index calculation method based on hardware resource failure factors. The specific method is as follows:

[0048] Figure 2This is a method for calculating the hardware health index. First, the probability density functions corresponding to the three failure factors are obtained. Experimental studies have shown that electromigration and hot carrier injection obey log-normal distributions, and time-dependent dielectric breakdown obeys Weibull distributions. Then, the reliability of hardware resources under the three failure factors is calculated based on the probability density function to describe the probability of hardware resources failing over time. Finally, an adaptive weighted average method is used to assign weights to the reliability of hardware resources under the three failure factors to determine the hardware health index.

[0049] According to the failure factors determined in step 1, the corresponding probability density function of each factor is obtained.

[0050] Among them, electromigration and hot carrier injection obey lognormal distribution, and time-dependent dielectric breakdown obeys Weibull distribution.

[0051] The probability density function of the lognormal distribution is defined as:

[0052]

[0053] Where t represents the failure time of hardware resources, σ represents the standard deviation of the failure time of hardware resources, and μ represents the mean failure time of hardware resources.

[0054] The probability density function of the Weibull distribution is defined as:

[0055]

[0056] Among them, t represents the hardware resource failure time, α represents the feature failure time, and β represents the shape parameter.

[0057] The reliability R(t) of the hardware resource under the failure factor is calculated based on the probability density function f(t) to describe the probability of hardware resources not failing over time. The calculation formula is as follows:

[0058]

[0059] An adaptive weighted average method is used to assign weights to the reliability of hardware resources under three factors to determine the hardware health index.

[0060] Assume that the reliability of hardware resources under three factors is x1, x2, and x3 respectively, and the corresponding weight is w i , the estimated true value is A, then the weighted average fusion value is: The weight coefficient satisfies: The total variance is: When the total error is the smallest, the weights of each factor are:

[0061]

[0062] The hardware health index value is between 0 and 1, where 0 indicates the worst hardware health and 1 indicates the best hardware health.

[0063] Step 3: Select IMA function operation monitoring parameters. Since the entire life cycle of IMA is always accompanied by intermittent failures, IMA errors caused by intermittent failures will be repaired by calling the error handler. However, the memory occupied by the repair process hinders the completion of the resident avionics function, making the memory occupied by the function completion exceed the allocated running memory. Therefore, the memory occupancy abnormal state index I is selected. ml Run monitoring parameters as a function.

[0064] Step 4: Construct a function health index calculation method to obtain the memory usage abnormal state index I of each functional module of IMA ml , and then calculate the memory usage abnormality index according to the function importance, and finally use it to replace the function health index, as follows:

[0065] Figure 3 The function health index calculation method is based on the function operation monitoring parameters selected in step (3), and the memory usage abnormal state index I of each functional module of IMA is obtained through system status detection. mli , assuming that functions are divided into 3 levels according to their importance, and level 3 is the highest. Then the total weight coefficients of the functions of each level are: level 1 is 1 / 6; level 2 is 1 / 3; level 3 is 1 / 2. Given that the number of level 1 functions is x, the number of level 2 functions is y, and the number of level 3 functions is z, then the IMA system memory usage abnormality index I ml for:

[0066]

[0067] Among them, x+y+z=n is the total number of functions of the IMA system.

[0068] The memory usage abnormality index ranges from 0 to 1, where 0 indicates the highest abnormality and 1 indicates no abnormality in memory usage. Using it instead of the functional health index reflects the full performance status of IMA from intact to lost functions. Among them, 1 indicates that the system functions well, and 0 indicates that the function is lost or cannot meet the operation requirements.

[0069] Step 5: Analyze the IMA airborne network performance status and determine the characterization parameters of the airborne network performance status.

[0070] Specifically, the requirements for internal interconnection of effective airborne electronic systems are mainly reflected in three aspects: bandwidth, real-time and reliability. The performance of airborne networks often has a significant impact on IMA systems. Data transmission rate, delay and bit error rate are often used to characterize the performance of airborne networks. Research shows that the bandwidth of future avionics interconnection networks should be able to support data transmission rates of more than 1Gb / s per channel, the sensor data transmission and distribution network should provide a transmission delay of no more than 100μs, and the bit error rate of detected data streams should not be greater than 10 -7 .

[0071] Step 6: Construct a network health index calculation method, divide the parameters characterizing the airborne network performance status into multiple levels through clustering according to the threshold, and finally use an adaptive weighted average method to assign weights to the levels of the three divided data to obtain the network health index.

[0072] The data transmission rate, delay and bit error rate are obtained during the operation of IMA, and they are divided into 10 levels by clustering according to the threshold provided in step 5. For each data set D = {x1, x2, ..., x n}, for clustering C = {C1, C2, ... C 10}Minimize the square error and get the final division result. The calculation formula is as follows:

[0073]

[0074] in, It is cluster C i The mean vector of .

[0075] The network health index is obtained by using the adaptive weighted average algorithm mentioned in step 2. The network health index takes a value between 0 and 1, where 0 represents the worst network health and 1 represents the best network health.

[0076] Step 7: According to the hardware health index obtained in step 2, the functional health index obtained in step 4, and the network health index obtained in step 6, the IMA system health index is calculated by weighted average method to determine the health status of the IMA system. The calculation formula is as follows:

[0077]

[0078] Among them, H represents the system health index, H1 represents the hardware health index, H2 represents the functional health index, and H3 represents the network health index.

[0079] The IMA system health index is divided into intact function, degraded performance, degraded function, severely degraded performance and loss of function from 1 to 0.

[0080] Table 1 shows the correspondence between the IMA system health index and the IMA health status.

[0081] Table 1

[0082]

[0083] The present invention also provides an IMA system three-dimensional health assessment index system construction system, comprising:

[0084] The hardware health index module is used to determine the reliability of the hardware resources under the failure factors according to the failure factors of the IMA hardware resources, and determine the hardware health index according to the reliability;

[0085] Functional health index module, used to obtain the memory usage abnormal status index of each functional module of IMA, and then calculate the memory usage abnormal index according to the function importance, and use the calculation result as the functional health index;

[0086] A network health index module is used to classify the characterization parameters of the airborne network performance status into multiple levels through clustering according to the threshold, and assign weights to each characterization parameter according to the divided levels to obtain the network health index;

[0087] The system health status module is used to calculate the IMA system health index by weighted average according to the hardware health index, the functional health index and the network health index, so as to determine the IMA system health status.

[0088] The present invention analyzes the factors that affect the health status of the system from the hardware resource level, the functional operation level, and the network performance level. By acquiring information parameters related to hardware resources, functional operation, and airborne networks, a system health index calculation method is constructed to obtain a comprehensive system health status, accurately characterizing the ability of the IMA system to complete the current flight mission. The present invention improves the reliability and safety of the IMA system and completes the all-round monitoring of the health status of the IMA system.

[0089] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for constructing a three-dimensional health assessment index system for an IMA system, characterized in that: The following steps are involved: Step 1: Determine the reliability of the hardware resources under the failure factors according to the failure factors of the IMA hardware resources, and determine the hardware health index according to the reliability; The method for determining the hardware health index is as follows: The reliability of hardware resources under failure factors is calculated according to the probability density function corresponding to the failure factors, and the reliability of hardware resources under failure factors is assigned weights by adaptive weighted average to determine the hardware health index; Step 2: Obtain the memory usage abnormal status index of each functional module of IMA, then calculate the memory usage abnormal index according to the function importance, and use the calculation result as the function health index; IMA system memory usage abnormal index The expression is as follows: in, is the total number of functions of the IMA system; Step 3: Clustering the characterization parameters of the airborne network performance status into multiple levels according to the threshold, and assigning weights to the levels of each characterization parameter to obtain a network health index; The method of characterizing parameter division is as follows: in, It is a cluster The mean vector of ; Step 4: Determine the health status of the IMA system based on the hardware health index, the functional health index, and the network health index.

2. A method for constructing a three-dimensional health assessment index system for an IMA system according to claim 1, characterized in that: The failure factors of the IMA hardware resources described in step 1 include electromigration, time-dependent dielectric breakdown and hot carrier injection.

3. The method for constructing a three-dimensional health assessment index system of an IMA system according to claim 1, characterized in that: The electromigration and hot carrier injection obey lognormal distribution, and the time-dependent dielectric breakdown obeys Weibull distribution; The probability density function of the lognormal distribution is as follows: in, Indicates the hardware resource failure time. represents the standard deviation of the hardware resource failure time, Indicates the mean failure time of hardware resources; The probability density function of the Weibull distribution is as follows: in, Indicates the hardware resource failure time. represents the feature failure time, Represents the shape parameter.

4. A method for constructing a three-dimensional health assessment index system of an IMA system according to claim 3, characterized in that: The calculation method of the reliability of the hardware resources is as follows: 。 5. The method for constructing a three-dimensional health assessment index system of an IMA system according to claim 1, characterized in that: The parameters characterizing the performance status of the airborne network in step 3 include data transmission rate, delay and bit error rate.

6. The method for constructing a three-dimensional health assessment index system of an IMA system according to claim 1, characterized in that: In step 4, the hardware health index, the functional health index and the network health index are weighted averaged to obtain the IMA system health index, thereby determining the health status of the IMA system.

7. A system for constructing a three-dimensional health assessment index system of an IMA system according to any one of claims 1 to 6, characterized in that: include, The hardware health index module is used to determine the reliability of the hardware resources under the failure factors according to the failure factors of the IMA hardware resources, and determine the hardware health index according to the reliability; Functional health index module, used to obtain the memory usage abnormal status index of each functional module of IMA, and then calculate the memory usage abnormal index according to the function importance, and use the calculation result as the functional health index; The network health index module is used to classify the characterization parameters of the airborne network performance status into multiple levels through clustering according to the threshold, and assign weights to each characterization parameter according to the divided levels to obtain the network health index; The system health status module is used to calculate the IMA system health index by weighted average according to the hardware health index, the functional health index and the network health index, so as to determine the IMA system health status.

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