Airborne system development guarantee classification method based on civil aircraft system architecture features

Abstract

The invention provides a civil aircraft system architecture feature-based airborne system development guarantee classification method. The method comprises the following steps of: obtaining and sorting design attributes of an airborne system; according to the design attributes, sequentially carrying out safety judgment, testability judgment and complexity judgment on the airborne system, and determining the development guarantee category of the airborne system. According to the development guarantee system classification method based on the civil aircraft system architecture features, safety judgment, testability judgment and complexity judgment are sequentially carried out on the to-be-developed airborne system, the development guarantee system category is determined, and compared with an existing system development guarantee classification method, the method has the advantage of being higher in project feasibility, and the development guarantee system classification efficiency is improved. And the actual reason for substituting the development error is comprehensively considered, so that the criterion dimension is more sufficient, the development cost is lower, and the development period is shorter.

Description

Technical Field

[0001] The invention belongs to the field of aircraft development requirement engineering, and in particular relates to an evaluation method for airborne system development assurance category. Background Art

[0002] Airborne system development assurance is a necessary activity in the development of civil aircraft systems and plays an important role in improving the safety level of aircraft. During the development of civil aircraft, the development assurance categories of airborne systems should be divided according to the attributes of airborne systems, so as to put forward appropriate development assurance requirements. The appropriate development assurance system classification method will help improve the feasibility of the project and control the development cost and progress on the basis of ensuring safety.

[0003] The traditional classification method of development assurance system only considers the safety dimension, but does not consider the system complexity and measurability dimensions. As a result, the definition of system development assurance categories does not conform to the engineering laws of system development, which may cause waste. Summary of the invention

[0004] In view of the background technology, the purpose of the present invention is to provide a development assurance system classification method based on civil aircraft system architecture characteristics to provide support for the development assurance activities of airborne systems.

[0005] To achieve the above objectives, the present invention adopts the following technical solutions:

[0006] An airborne system development assurance classification method based on civil aircraft system architecture characteristics, characterized by comprising:

[0007] obtaining and organizing design attributes of the airborne system,

[0008] According to the design attributes, safety judgment, testability judgment and complexity judgment are carried out on the airborne system in sequence to determine the development assurance category of the airborne system.

[0009] The design attribute recommendations include: the number of functional requirements, the degree of system integration, and the logical complexity of the functions. For example: whether the number of functional requirements is greater than a certain defined value, whether the system has a central / core control configuration item, and whether the system has functional logic for multi-variable combination operations. The specific dimensions and values ​​of the design attributes are determined based on the experience of the development team and the technical maturity of the system.

[0010] Preferably, the safety judgment adopts a safety analysis conclusion comparison method, based on the system's FHA (Functional Hazard Assessment) conclusion and the conclusion of the higher-level system FTA (Fault Tree Analysis) assigned to each level, the higher of the two is taken; if the level of the higher one is not higher than level C, the system is judged to be a low safety category.

[0011] Preferably, the testability judgment adopts the exhaustive table determination method of the working condition. If all the working conditions of the system can be listed according to the exhaustive table of working conditions, the system is judged to be an exhaustive working condition category. In the exhaustive table of system working conditions, the working modes and failure working modes of all the lower-level systems in the system should be listed, and the series / parallel systems should be distinguished to carry out combination / arrangement to generate the corresponding relationship between the working conditions and the set of working modes of the lower-level systems. For a series system, the working condition of the system should be a set of operating modes of the lower-level systems (lower-level systems with two or more normal working modes) contained in the system, and may even include the operating sequence of the lower-level systems that may affect the functional results of the system; for a parallel system, if the scope of influence of the operating mode of the lower-level system of the system can be proved by the architectural characteristics, the working condition of the system can correspond to the enumeration of the working conditions of the parallel subsystems. The working conditions of the system that contains software and / or programmable electronic hardware at the next layer or the current layer are not exhaustive. If a system is directly evaluated to the component level and is identified as an exhaustible operating condition category, the lower-level systems of this system can also be directly classified as exhaustible operating condition category systems, and the lower-level systems can obtain development assurance approval without the need for exhaustive operating condition enumeration and verification.

[0012] The characteristics of the exhaustive working condition table determination method determine that the technical and verification cost risks of carrying out exhaustive working conditions in high-level systems are huge, and the system development team should carefully consider evaluating high-level systems as exhaustive working condition categories.

[0013] The complexity judgment adopts the system design attribute judgment method. When multiple of the expected design attributes meet the high complexity criterion at the same time, or a single design attribute meets the high complexity criterion, the airborne system is judged to be a high complexity category, otherwise the system is judged to be a low complexity category.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The development assurance system classification method based on the system architecture characteristics of civil aircraft of the present invention sequentially conducts safety judgment, testability judgment, and complexity judgment on the airborne system to be developed to determine its development assurance system category. Compared with the existing system development assurance classification method, this method has the advantages of higher project feasibility, more comprehensive judgment dimension (comprehensively considering the actual reasons for development errors), lower development cost, and shorter development cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a flow chart of an embodiment of the present invention. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0018] The development assurance system classification method based on the civil aircraft system architecture characteristics of the present invention is used to classify the development assurance categories of the system, thereby proposing appropriate development assurance requirements. Figure 1 As shown, the implementation process is as follows: analyze and organize the design attributes of the development system; conduct safety judgment, testability judgment and complexity judgment on the airborne system in sequence according to the design attributes, and determine the development assurance category of the airborne system.

[0019] The design attributes include a system function list related to complexity judgment, an FHA conclusion related to safety judgment, an internal schematic diagram related to testability judgment and complexity judgment, a technology maturity related to complexity judgment, and a mathematical model of functions related to complexity judgment.

[0020] Conduct safety judgment: The judgment criteria are "the FHA conclusion of the system and the conclusion of the high-level system FTA assigned to this system (the higher of the two)". If the system is judged to be a low safety category, the classification process is directly terminated; FHA and FTA are methods defined in the common standard SAE ARP4761, which have been clearly defined in the aviation industry. The analysis process is not an innovation of the present invention, but their results are used here.

[0021] Carry out measurability judgment, the criterion is "whether the system working condition can be listed according to the exhaustive working condition table", if the system is judged to be an exhaustive working condition category, the classification process is terminated, according to Figure 1 It can be seen that if it has been determined to be a certain category, the result is obtained directly. If it does not meet the criteria, the next stage of classification judgment is carried out. The exhaustive process of working conditions is to first use Table 1 to count the working modes of system components, and then use Table 2 to exhaustively enumerate the system working conditions (the working conditions in Table 2 should select the combination or arrangement of the working modes of system components in Table 1 according to the system principle):

[0022] Table 1 System component working mode statistics

[0023]

[0024] Table 2 System operating conditions exhaustive table

[0025]

[0026] Carry out complexity judgment, the criterion is "whether the system design attributes meet the predefined design attribute criteria", and judge the system as a high complexity category or a low complexity category. In fact, this work is done before the preliminary design of the system, so the design attributes of the system are not certain at this time, and can only be expected based on prototypes or design experience.

[0027] For example, if two or more of the following conditions are met at the same time, it is considered to be a high complexity category:

[0028] Functional requirements ≥ 30;

[0029] The system has multiple working modes, and the switching of working modes is managed by a core configuration item at the next level, or more than 80% of the system's functions rely on a core configuration item at the next level to be implemented (such as bus-controlled systems, star systems, and string systems). The configuration item here may be software or programmable electronic hardware;

[0030] The lower-level configuration items contain software or programmable electronic hardware, and the functions of these software or programmable electronic hardware have complex logic (the logic of functions such as acquisition, conversion, signal processing, recording, self-test, etc. with no more than 5 input variables is considered non-complex);

[0031] The technical maturity of the system prototype is lower than level 7 defined in GJB 7688.

[0032] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A classification method for airborne system development assurance based on civil aircraft system architecture characteristics, characterized in that: include: Obtaining and organizing design attributes of the airborne system; According to the design attributes, safety judgment, testability judgment and complexity judgment are carried out on the airborne system in sequence to determine the development assurance category of the airborne system.

2. The airborne system development assurance classification method according to claim 1 is characterized in that: The design attributes include the number of functional requirements, the degree of integration of the system, the logical complexity of the functions and / or the technical maturity.

3. The airborne system development assurance classification method according to claim 2 is characterized in that: The safety judgment adopts the safety analysis conclusion comparison method. According to the FHA conclusion of the airborne system and the conclusion of the higher-level system FTA corresponding to each level in the airborne system assigned to the level, the higher one is taken to determine whether the level of the higher one is higher than level C. If so, the airborne system is determined to be at a high safety level. If not, the airborne system is determined to be at a low safety category.

4. The airborne system development assurance classification method according to claim 2 is characterized in that: The testability judgment adopts the working condition exhaustive table judgment method to judge whether all the working conditions of the system can be listed according to the working condition exhaustive table. If so, it is judged that the airborne system belongs to the exhaustible working condition category.

5. The airborne system development assurance classification method according to claim 4 is characterized in that: The exhaustive operating condition table includes the expected operating modes and failure operating modes of all lower-level systems in the airborne system, and generates a correspondence between system operating conditions and a set of lower-level system operating modes based on the series / parallel characteristics of the airborne system.

6. The airborne system development assurance classification method according to claim 5 is characterized in that: For a series system, the operating conditions of the onboard system correspond to the set of permutations of the operating modes of the lower-level systems with behavioral functions, including the operating timing of the lower-level systems that affect the functional results of the system; for a parallel system, determine whether the scope of influence of the operating modes of the lower-level systems of the system can be proved by architectural features. If so, the operating conditions of the system correspond to the combined set of the operating conditions of the lower-level systems.

7. The airborne system development assurance classification method according to any one of claims 4 to 6, characterized in that: Determine whether the next level of the onboard system includes a system of software and / or programmable electronic hardware, and if so, determine that the operating conditions of the onboard system are not exhaustive.

8. The airborne system development assurance classification method according to any one of claims 4 to 6, characterized in that: Determine whether the airborne system is directly evaluated to the component level, and the component level is identified as an exhaustible operating condition category. If so, the lower-level system of the airborne system is classified as an exhaustible operating condition category system, and the lower-level system can obtain development assurance approval without carrying out exhaustive operating condition enumeration and verification.

9. The airborne system development assurance classification method according to claim 2 is characterized in that: The complexity judgment method includes: when multiple of the design attributes meet the high complexity criterion at the same time, or a single design attribute meets the high complexity criterion, then judging that the airborne system is of a high complexity category.

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