Hydraulic system modeling method and device based on MBSE

Abstract

The invention discloses a hydraulic system modeling method and device based on MBSE, and belongs to the technical field of hydraulic systems.The hydraulic system modeling method comprises the steps that requirements of an aero-engine hydraulic system and interested parties of the aero-engine hydraulic system are collected, and the requirements are converted into a requirement table and a requirement diagram based on an MBSE model; according to the requirements of the aero-engine hydraulic system and the interested parties thereof, the functions of the hydraulic system are refined and decomposed; and distributing the refined decomposition function of the hydraulic system to each component, and constructing to obtain a hydraulic system architecture model. According to the method, the MBSE method is adopted, and the performance of the system can be accurately predicted before actual manufacturing and testing by creating and analyzing a detailed model of the system, so that an engineer can identify and solve potential design problems through the prediction capability, and the reliability of a final product is remarkably improved; the problems that in the development process of an existing hydraulic system, early-stage demand definition and later-stage design management and control of the system are difficult, and verification and tracing between the systems are difficult can be effectively solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydraulic systems, and in particular relates to a hydraulic system modeling method and device based on MBSE. Background Art

[0003] The hydraulic system of an aircraft engine is a typical complex system with a complex structure, multiple subsystems, subsystems, and numerous parts. In its development and design process, it involves multidisciplinary, multi-field, and multi-level issues. In the design process, engineers may have different understandings of the same design document, the processing efficiency of text language is not high, and it takes a lot of time to refine and understand each document. These defects greatly reduce the development efficiency of complex systems. Compared with document-based systems engineering, model-based systems engineering (MBSE) adopts a model-centric approach that covers the entire life cycle of complex systems. Models replace traditional documents, voice recordings, videos, and tables to meet design requirements, interface requirements, performance requirements, functions, indicators, and solutions, and at the same time establish a unified standard model for updating. This can achieve maintenance and update iterations of complex systems.

[0004] However, the existing document-based systems engineering methods still face two problems:

[0005] (1) Difficulties in defining system requirements and controlling subsequent design;

[0006] (2) Verification and traceability between systems are difficult. Summary of the invention

[0007] The purpose of the present invention is to provide a hydraulic system modeling method and device based on MBSE to address the above-mentioned deficiencies in the prior art, so as to solve the problems of difficulties in demand definition and subsequent design management of existing hydraulic systems, as well as great difficulty in verification and traceability between systems.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is:

[0009] In a first aspect, a hydraulic system modeling method and device based on MBSE comprises the following steps:

[0010] S1. Collect the requirements of the aircraft engine hydraulic system and its stakeholders, and convert the requirements into a requirement table and a requirement diagram based on the MBSE model;

[0011] S2. Decompose the functions of the hydraulic system in detail according to the needs of the aircraft engine hydraulic system and its stakeholders;

[0012] S3. Allocate the decomposed functions of the hydraulic system to each component to construct a hydraulic system architecture model.

[0013] Furthermore, S1 includes the following sub-steps:

[0014] S11. Collect the requirements of the aircraft engine hydraulic system and its stakeholders, convert the requirements into itemized and textual forms, and input them into the MBSE model, and then convert them into requirement tables and requirement diagrams;

[0015] S12, dividing the requirements in the requirement table and the requirement diagram into functional requirements and performance requirements;

[0016] S13. Assign an ID code and text description to each functional requirement and performance requirement.

[0017] Furthermore, stakeholders in S11 include regulators, pilots, manufacturers, aircraft engine manufacturers, and maintenance and service providers.

[0018] Furthermore, the performance requirements are the efficiency and reliability of the hydraulic system during operation, including the maximum load capacity, operating temperature range, failure rate, and maintenance cycle of the hydraulic system;

[0019] Functional requirements are the basic functions of the hydraulic system, including the responsiveness of the control system, the operating accuracy of the hydraulic components, and the stability of the hydraulic components under various working conditions.

[0020] Furthermore, S1 also includes a constraint module for refining the relationship between non-functional constraint requirements and technical indicators.

[0021] Further, S2 includes the following sub-steps:

[0022] S21. Based on the needs of the aircraft engine hydraulic system and its stakeholders, use the SysML use case diagram and behavior diagram in MBSE to create the functions and activities of the hydraulic system and its subsystems, as well as the interaction between each sub-function, and refine the functions in the hydraulic system into multiple use cases;

[0023] S22. Add other nodes according to the actual functional business logic, and use activity diagrams to perform detailed behavioral analysis on the use cases to be analyzed;

[0024] S23. Use activity diagrams or state machine diagrams to expand the activities of the first layer again and display the behaviors of each component during the activity.

[0025] Furthermore, other nodes in S22 include creating an initial node, calling a behavior action, and a decision node in the right view area of ​​the activity diagram; and typing a functional behavior name on the right side of each calling behavior action.

[0026] Furthermore, the behavior analysis in S22 includes behavior analysis of the power part, behavior analysis of the monitoring part, behavior analysis of the auxiliary part, behavior analysis of the control part, behavior analysis of the execution part and behavior analysis of the transmission part.

[0027] Furthermore, S3 includes the following sub-steps:

[0028] S31. Use SysML module definition diagrams to create components of the hydraulic system, as well as construct subsystems, subsystems and components of the hydraulic system;

[0029] S32. Using SysML's internal module diagram, we can create the signal and interactive transmission between each subsystem and each device of the hydraulic system;

[0030] S33, construct a traceability matrix. When the active use cases in the hydraulic system meet the requirements issued by the top level, they are represented in the traceability matrix by using the refine relationship;

[0031] S34. Locate unrefined or unmet requirements, modules, and components based on the traceability matrix, and then obtain a detailed matrix that shows the relationship between requirements, use cases, and system components.

[0032] In a second aspect, a hydraulic system modeling device based on MBSE includes:

[0033] A data acquisition and conversion module, which is used to collect the requirements of the aircraft engine hydraulic system and its stakeholders, and convert the requirements into a requirement table and a requirement diagram based on the MBSE model;

[0034] The hydraulic behavior analysis module is used to break down the functions of the hydraulic system according to the needs of the aircraft engine hydraulic system and its stakeholders;

[0035] The model building module is used to allocate the functions of the hydraulic system to various components to construct a hydraulic system architecture model.

[0036] The hydraulic system modeling method and device based on MBSE provided by the present invention have the following beneficial effects:

[0037] The present invention achieves accurate management and optimization of the entire life cycle of the hydraulic system through formal modeling, performance prediction and fault analysis; and adopts the MBSE method to create and analyze a detailed model of the system, which can accurately predict the performance of the system before actual manufacturing and testing. Such predictive capabilities enable engineers to identify and solve potential design problems, thereby significantly improving the reliability of the final product. Through early verification of the model, the invention also helps to reduce the number of design iterations and shorten the product development cycle; it can effectively solve the problems of early system demand definition and later design management and control difficulties in the development process of existing hydraulic systems, as well as the difficulty of verification and traceability between systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a flowchart of the hydraulic system modeling method based on MBSE of the present invention.

[0039] Figure 2 It is the overall demand table of the hydraulic system of the present invention.

[0040] Figure 3 This is the performance requirement table of the present invention.

[0041] Figure 4 This is the functional requirement table of the present invention.

[0042] Figure 5 This is the performance requirement diagram of the present invention.

[0043] Figure 6 The requirements are refined through use case diagrams for the present invention.

[0044] Figure 7 This is a detailed system-level behavior analysis of the present invention.

[0045] Figure 8 Component behavior analysis one is performed for the present invention.

[0046] Fig. 9 This is a behavior analysis of the transmission components of the present invention.

[0047] Fig.10 This is the second behavior analysis of the transmission component of the present invention.

[0048] Fig.11 Behavior analysis of auxiliary components of the present invention.

[0049] Fig.12 The present invention monitors part of the behavior analysis.

[0050] Fig.13 An activity diagram that allocates each function of the present invention to a part.

[0051] Fig.14 This is the activity diagram of the control valve of the present invention.

[0052] Fig.15 This is the data analysis activity diagram of the fact system of the present invention.

[0053] Fig.16 It is the system-level framework of the hydraulic system of the present invention.

[0054] Fig.17 This is the hydraulic system architecture model of the present invention.

[0055] Fig.18 This is an analysis of the logical architecture of the hydraulic system of the present invention.

[0056] Fig.19 The matrix diagram is refined for the present invention. DETAILED DESCRIPTION

[0057] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0058] Example 1

[0059] This embodiment provides a hydraulic system modeling method and device based on MBSE, which can effectively solve the problems of early system demand definition and later design control difficulties in the development process of existing hydraulic systems, as well as the difficulty of verification and traceability between systems. Figure 1 , which specifically includes the following:

[0060] Step S1: Collect the requirements of the aircraft engine hydraulic system and its stakeholders, and convert the requirements into a requirement table and a requirement diagram based on the MBSE model, which specifically includes the following sub-steps:

[0061] Step S11: Reference Figure 2 , collect the requirements of the aircraft engine hydraulic system and its stakeholders, convert the requirements into itemized and textual forms, or input them into the MBSE model through Excel or CSV files, and convert them into requirement tables and requirement diagrams;

[0062] Specifically, this embodiment clarifies the R&D design tasks through analysis of existing design data, and identifies the stakeholders involved in the design process, where the stakeholders include regulatory agencies, pilots, manufacturers, aircraft engine manufacturers, maintenance and service providers, etc.

[0063] Step S12: Classify the requirements proposed by various stakeholders and divide the requirements in the hydraulic system requirement table and requirement diagram into functional requirements and performance requirements;

[0064] Among them, reference Figure 3 The performance requirements are the efficiency and reliability of the hydraulic system during operation, including the maximum load capacity, operating temperature range, failure rate and maintenance cycle of the hydraulic system; specify the specific performance standards that the system or components in the system should meet. For example, response time, efficiency improvement, maintenance time, etc. These performance requirements will be converted into specific indicators of the components, and the parameters of the indicators of each component will be constrained through the constraint module to meet the specific indicator effects of each component.

[0065] refer to Figure 4 Functional requirements are the basic functions of the hydraulic system, including the responsiveness of the control system, the operating accuracy of the hydraulic components, and the stability of the hydraulic components under various working conditions; they involve specific functional requirements of the system, such as precise control, high integration, self-diagnosis and inspection, and easy maintenance. Functional requirements are usually met or further refined by a certain "behavior" (such as "activity" or Activity).

[0066] Step S13: assign an ID code and text description to each functional requirement and performance requirement;

[0067] refer to Figure 5 Specifically, this embodiment assigns a unique identifier "ID" to each requirement and provides a detailed description "Test" for each requirement. The header of the requirement table consists of ID and Test. ID indicates the level of the requirement. For example, the ID of "response speed" is 2.4, which is below performance requirement 2. If it has a requirement at the next level, its ID will be 2.4.1, 2.4.2, and so on.

[0068] For example, the detailed requirement of "precise control" in the functional requirement is "the system should have the ability to accurately control engine components, such as precise adjustment of turbine blade angle and fuel injection amount". The detailed requirement description of "high efficiency" in the performance requirement is "the efficiency of the hydraulic system should reach more than 90%". After sorting out the performance requirements and functional requirements, input them into the MBSE model;

[0069] By using the requirement diagram in SysML to convert the functional requirements and performance requirements in the above requirement table into a requirement diagram, we can more clearly know which category of requirements each small requirement belongs to, as well as the ID code and text description of each requirement. The requirement diagram is as follows: Figure 5 shown.

[0070] Step S14: Based on the requirement graph established in S13, if some requirements involve non-functional constraints (such as numerical values ​​or mathematical expressions), a constraint module should be established, and the relationship between the requirements and technical indicators should be refined through the "refine" relationship.

[0071] Step S2: According to the requirements of the aircraft engine hydraulic system and its stakeholders, the functions of the hydraulic system are broken down into smaller parts, which specifically include the following sub-steps:

[0072] Step S21: Reference Figure 6 According to the needs of the aircraft engine hydraulic system and its stakeholders, the use case diagram and behavior diagram of SysML in MBSE are used to create the functions and activities of the hydraulic system and its subsystems, as well as the interaction relationship between each sub-function, and the functions in the hydraulic system are refined into multiple use cases;

[0073] Specifically, use SysML's activity diagrams, use case diagrams and other behavior diagrams to create the functions and activities of the hydraulic system and its subsystems, as well as the interactions between each sub-function. According to the requirements sorted out in S11, the functions of the hydraulic system are decomposed into small use cases and refined, such as landing gear operation, valve opening control, and brake system activation.

[0074] This embodiment takes the operation of retracting and extending the landing gear by the hydraulic system as an example for analysis.

[0075] In the early stage, aircraft engine manufacturers, airlines and regulatory agencies will put forward overall requirements for the hydraulic system to ensure that each component of the system meets the relevant specifications. Airlines will cooperate with maintenance service providers and perform daily maintenance and fault detection on the system. After the preliminary work is ready, the airline will work with the pilot to start the system to ensure the smooth and efficient retraction and extension of the landing gear to ensure the safe use of the system.

[0076] Force generation and supply, pressure and flow control, contamination control, actuation mechanisms, system monitoring and feedback, fluid transfer, each use case represents a top-level requirement.

[0077] Step S22: Reference Figure 4 , according to the actual functional business logic, add other nodes, and use activity diagrams to perform detailed behavioral analysis on the use cases to be analyzed; according to the process of S21, further decompose the landing gear retraction and extension function step by step. Analyze the functional behavior of the system, create initial nodes, call behavior actions, decision nodes, etc. in the right view area of ​​the activity diagram, and for each call behavior action, pay attention to type the functional behavior name on the right side of its colon.

[0078] According to the actual functional business logic, add other nodes and conduct detailed analysis in the form of creating activity diagrams for the use cases to be analyzed. Figure 7 to Figure 12 , specifically including the following:

[0079] Behavior analysis includes power part behavior analysis, monitoring part behavior analysis, auxiliary part behavior analysis, control part behavior analysis, execution part behavior analysis and transmission part behavior analysis. Take the landing gear as an example:

[0080] When the pilot issues a landing gear extension or retraction command, the control electronics start the hydraulic pump, which draws hydraulic oil from the hydraulic tank, pressurizes it, and transmits it to the hydraulic cylinder. (Hydraulic pump)

[0081] When the hydraulic pump is working, the accumulator stores a part of the hydraulic energy. When the hydraulic pump cannot meet the instantaneous high demand, the accumulator releases the stored hydraulic energy to ensure the stable operation of the system. (Accumulator)

[0082] When hydraulic oil flows into the hydraulic cylinder, it pushes the piston rod to extend, driving the landing gear to extend; when operating in the reverse direction, the hydraulic oil flows back, the piston rod retracts, and the landing gear is retracted. (Hydraulic cylinder)

[0083] In some landing systems, hydraulic motors may be used for auxiliary components, such as the opening and closing of landing gear doors; hydraulic oil flows into the hydraulic motor, driving it to rotate, thereby realizing the movement of the auxiliary component. (Hydraulic Motor)

[0084] The control valve adjusts the flow and pressure of the hydraulic oil to ensure precise control of the extension and retraction of the landing gear. It is necessary to control the electronic equipment and adjust the opening of the control valve.

[0085] The pressure sensor monitors the pressure of the hydraulic system in real time and feeds the data back to the control electronics; if the pressure is abnormal, the pressure switch is activated to protect the system and sound an alarm.

[0086] The control electronic equipment receives instructions from the pilot and coordinates the operation of various components of the hydraulic system; it adjusts the working status of control valves, hydraulic pumps and other components in real time.

[0087] The hydraulic oil is transmitted to the hydraulic cylinder through the hydraulic pipeline, and the return hydraulic oil returns to the hydraulic oil tank through the hydraulic pipeline.

[0088] During the operation of the hydraulic system, the hydraulic oil passes through the cooler to keep it at a suitable operating temperature at all times.

[0089] During the entire system operation, the hydraulic oil passes through the filter during the circulation process to ensure the cleanliness of the hydraulic oil in the system and avoid hydraulic failures caused by low cleanliness of the hydraulic oil.

[0090] The hydraulic pump draws hydraulic oil from the hydraulic oil tank and supplies the entire system. The returned hydraulic oil is cooled and filtered in the oil tank to maintain the quality of the hydraulic oil.

[0091] When the system pressure is too high, the safety valve opens automatically to release excess pressure and protect the smooth operation of the system.

[0092] When the hydraulic system fails or the system loses pressure, manual hydraulic power is provided. In an emergency, the pilot or ground maintenance personnel can manually operate the emergency manual pump to complete the extension and retraction of the landing gear.

[0093] Step S23: Use behavior diagrams such as activity diagrams and state machine diagrams to expand the activities of the first layer again and display the behaviors of each detailed component during the landing gear extension and retraction process.

[0094] After further refinement, the activity diagram obtained from the first-level operation analysis and the second-level functional decomposition activity diagrams of each part.

[0095] Step S3: Reference Fig.13 , Fig.14 and Fig.15 , the functions of the hydraulic system are allocated to each component, and the hydraulic system architecture model is constructed. The hydraulic system architecture design is based on the activity list identified by the system function refinement analysis, considering the grouping and merging of activities, designing the division of the internal components of the system, and completing the allocation of activities to components; after completing the component allocation, it is necessary to return to the component function analysis activity diagram, add service lanes to supplement the allocation of activities to components, and define the interfaces of the corresponding components; finally, the various functions are allocated to the various components, to the activity diagram with lanes, which specifically includes the following sub-steps:

[0096] Step S31, reference Fig.16 , using SysML's module definition diagram to create the components of the hydraulic system, as well as to construct the various subsystems, subsystems and components of the hydraulic system;

[0097] Specifically, in order to meet the overall functional requirements of the hydraulic system, the module definition diagram of SysML is used to create the various components of the hydraulic system. For example, "Block" is used to create the "power part", "execution part", control part, transmission part, auxiliary part and monitoring part. And "Directed Composition" is used to connect with the hydraulic system to indicate the major parts of this hydraulic system. Finally, the module definition diagram is obtained.

[0098] refer to Fig.17 In this way, you can also create various devices under various components. For example, the power part is composed of hydraulic pumps, hydraulic oil and other main components. Similarly, you can create various subsystems, subsystems, and various components of the complete hydraulic system in the block definition diagram (BDD).

[0099] Step S32, reference Fig.18,Using SysML’s internal module diagram, it is possible to create the signal and interactive transmission between each subsystem and each device of the hydraulic system;

[0100] In the early stage of function refinement and allocation of activities to various components, the interaction item transmission situation was analyzed, and the interfaces between components and complementary components, and between components and upper-level systems were identified. The internal module diagram of SysML is used to create the signal and interaction transmission between each subsystem and each device of the hydraulic system. For example: the hydraulic pump under the power part is the main power source. It extracts hydraulic oil from the oil tank and pressurizes it to provide power for the system. In this action, the oil tank transmits an interaction item to the hydraulic pump through the "filter", "cooler" and transmission pipeline. This interaction item is "hydraulic oil". Therefore, this internal module diagram can clearly represent the transmission between each system and its upper, same, or lower level systems and other equipment. Finally, the internal module diagram is completed.

[0101] Step S33: construct a traceability matrix. When the active use cases in the hydraulic system meet the requirements issued by the top level, they are represented in the traceability matrix by using the refine relationship.

[0102] Step S34: Locate unrefined or unmet requirements, modules, and components according to the traceability matrix, and then obtain a detailed matrix showing the relationship between requirements, use cases, and system components, such as Fig.19 shown.

[0103] Example 2

[0104] A hydraulic system modeling device based on MBSE, comprising:

[0105] A data acquisition and conversion module, which is used to collect the requirements of the aircraft engine hydraulic system and its stakeholders, and convert the requirements into a requirement table and a requirement diagram based on the MBSE model;

[0106] The hydraulic behavior analysis module is used to break down the functions of the hydraulic system according to the needs of the aircraft engine hydraulic system and its stakeholders;

[0107] The model building module is used to allocate the functions of the hydraulic system to various components to construct a hydraulic system architecture model.

[0108] Although the specific implementation of the invention is described in detail in conjunction with the drawings, it should not be understood as limiting the scope of protection of this patent. Within the scope described in the claims, various modifications and variations that can be made by those skilled in the art without creative work still fall within the scope of protection of this patent.

Claims

1. A hydraulic system modeling method based on MBSE, characterized in that: The following steps are involved: S1. Collect the requirements of the aircraft engine hydraulic system and its stakeholders, and convert the requirements into a requirement table and a requirement diagram based on the MBSE model; S2. Decompose the functions of the hydraulic system in detail according to the needs of the aircraft engine hydraulic system and its stakeholders; S3. Allocate the decomposed functions of the hydraulic system to each component to construct a hydraulic system architecture model.

2. The hydraulic system modeling method and device based on MBSE according to claim 1, characterized in that: The S1 comprises the following sub-steps: S11. Collect the requirements of the aircraft engine hydraulic system and its stakeholders, convert the requirements into itemized and textual forms, and input them into the MBSE model, and then convert them into requirement tables and requirement diagrams; S12, dividing the requirements in the requirement table and the requirement diagram into functional requirements and performance requirements; S13. Assign an ID code and text description to each functional requirement and performance requirement.

3. The MBSE-based hydraulic system modeling method and device according to claim 2, characterized in that: The stakeholders in S11 include regulators, pilots, manufacturers, aircraft engine manufacturers, maintenance and service providers.

4. The MBSE-based hydraulic system modeling method and device according to claim 2, characterized in that: The performance requirements are the efficiency and reliability of the hydraulic system during operation, including the maximum load capacity, operating temperature range, failure rate and maintenance cycle of the hydraulic system; Functional requirements are the basic functions of the hydraulic system, including the responsiveness of the control system, the operating accuracy of the hydraulic components, and the stability of the hydraulic components under various working conditions.

5. The MBSE-based hydraulic system modeling method and device according to claim 2, characterized in that: The S1 also includes a constraint module for refining the relationship between the requirements of non-functional constraints and technical indicators.

6. The MBSE-based hydraulic system modeling method and device according to claim 1, characterized in that: The S2 comprises the following sub-steps: S21. Based on the needs of the aircraft engine hydraulic system and its stakeholders, use the SysML use case diagram and behavior diagram in MBSE to create the functions and activities of the hydraulic system and its subsystems, as well as the interaction between each sub-function, and refine the functions in the hydraulic system into multiple use cases; S22. Add other nodes according to the actual functional business logic, and use activity diagrams to perform detailed behavioral analysis on the use cases to be analyzed; S23. Use activity diagrams or state machine diagrams to expand the activities of the first layer again and display the behaviors of each component during the activity.

7. The MBSE-based hydraulic system modeling method and device according to claim 6, characterized in that: The other nodes in S22 include creating an initial node, calling a behavior action, and a decision node in the right view area of ​​the activity diagram; and typing a functional behavior name on the right side of each calling behavior action.

8. The MBSE-based hydraulic system modeling method and device according to claim 6, characterized in that: The behavior analysis in S22 includes behavior analysis of the power part, behavior analysis of the monitoring part, behavior analysis of the auxiliary part, behavior analysis of the control part, behavior analysis of the execution part and behavior analysis of the transmission part.

9. The MBSE-based hydraulic system modeling method and device according to claim 1, characterized in that: The S3 comprises the following sub-steps: S31. Use SysML module definition diagrams to create components of the hydraulic system, as well as construct subsystems, subsystems and components of the hydraulic system; S32. Using SysML's internal module diagram, we can create the signal and interactive transmission between each subsystem and each device of the hydraulic system; S33, construct a traceability matrix. When the active use cases in the hydraulic system meet the requirements issued by the top level, they are represented in the traceability matrix by using the refine relationship; S34. Locate unrefined or unmet requirements, modules, and components based on the traceability matrix, and then obtain a detailed matrix that shows the relationship between requirements, use cases, and system components.

10. A hydraulic system modeling device based on MBSE, characterized in that: include: A data acquisition and conversion module, which is used to collect the requirements of the aircraft engine hydraulic system and its stakeholders, and convert the requirements into a requirement table and a requirement diagram based on the MBSE model; The hydraulic behavior analysis module is used to break down the functions of the hydraulic system according to the needs of the aircraft engine hydraulic system and its stakeholders; The model building module is used to allocate the functions of the hydraulic system to various components to construct a hydraulic system architecture model.

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