An OPM-based simulation modeling method for aircraft system failure
By using the OPM method to model the structure, function, and behavior of aircraft systems, and using OPD object process diagrams and influence links to describe the state changes of system elements, the problem of insufficient modeling complexity and accuracy in existing technologies is solved, and the effects of simplified modeling and improved simulation prediction are achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHENGDU AIRCRAFT DESIGN INST OF AVIATION IND CORP OF CHINA
- Filing Date
- 2022-12-29
- Publication Date
- 2026-05-15
AI Technical Summary
Existing aircraft system fault simulation modeling methods are complex, requiring modelers to be familiar with the system structure and fault propagation relationships. This results in significant differences between different system models, insufficient modeling accuracy and practicality, and difficulty in unifying the handling of these differences.
An OPM-based aircraft system fault simulation modeling method is adopted. The structure, function and behavior of complex systems are modeled through a unified type view. The system elements and their state changes are described using OPD object process diagrams and influence links, which support dynamic correction and verification.
It improves modelers' overall understanding of the system, simplifies modeling methods, reduces learning time, improves model development efficiency and simulation prediction accuracy, and reduces the complexity of simulation analysis.
Smart Images
Figure CN116187012B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of complex system organization modeling and simulation analysis technology, specifically involving an OPM-based aircraft system fault simulation modeling method. Background Technology
[0002] Aircraft complex system fault simulation, as a major part of system fault diagnosis, aims to analyze the diagnosability of complex systems, thereby ultimately achieving rapid isolation of aircraft system faults. Current aircraft system fault simulation modeling methods mostly rely on fault trees, symbolic directed graphs, and other methods to establish qualitative models of the system based on its structure and working principles, and to create cause-effect graphs or correlation matrices of faults to provide diagnostic conditions for the faults.
[0003] While the aforementioned simulation modeling methods can fully consider fault effects and analyze the system's fault diagnosability at a deeper level, their drawback is that they require modelers to be extremely familiar with the system structure, fault propagation, and impact relationships. However, system simulation modeling methods or tools are often quite complex. This leads to a situation where system designers, despite being familiar with the system itself, cannot skillfully apply the modeling methods and tools, while professional modelers often lack a full understanding of the complex system's architecture. Ultimately, this results in significant differences in simulation models for different systems, insufficient modeling accuracy and practicality, and difficulty in standardizing modeling methods. Summary of the Invention
[0004] The purpose of this invention is to solve the problem of failure rate prediction for airborne systems of military aircraft. This paper provides an aircraft system failure simulation modeling method based on OPM (Object-Process Methodology). By using a unified type view, the structure, function and behavior of complex systems can be modeled, making it easy to maintain the consistency of model elements. Through deduction, the model can be dynamically corrected and verified, thereby improving the efficiency of model development.
[0005] The technical solution of this invention:
[0006] An OPM-based aircraft system fault simulation modeling method includes the following steps:
[0007] Step 1: Select the aircraft system to be simulated and determine its system functions and components;
[0008] Step 2: Determine the OPM modeling object elements based on the finished products, structural components, and cables included in the selected aircraft system;
[0009] Step 3: Based on the system functions and finished product objects of the selected aircraft system, define and create the system's OPD object process diagram;
[0010] Step 4: Specify the status of each object element in the aircraft system to characterize the actual working status of each finished product, structural component, and cable in the system;
[0011] Step 5: Use the specified state of each object element as the state value of each object element in OPD;
[0012] Step Six: Match the state change process for stateful object elements;
[0013] Step 7: Use influence links in OPD to connect the object state to the matching process;
[0014] Step 8: Determine the fault propagation path between object elements in the selected system based on the composition relationship between the finished products and corresponding structural components and cables. The key to the fault propagation path is the abnormal state of a certain object element as a direct representation of the system fault.
[0015] Step 9: According to the fault propagation path between the selected object elements in the system, determine the impact of a change in the state of a certain object element on other object elements in the system, and use impact links to connect a certain object element in the system from an abnormal state to the output state of other object elements through a process.
[0016] Step 10: If the fault propagation path in the selected system points to another system outside the selected system, then in the same OPD view, repeat steps 1 to 9 for the other system until the end of the fault propagation path.
[0017] Step 11: Perform simulation and deduction of the fault model to check its rationality and feasibility.
[0018] Furthermore, in step one, the system components include: finished LRU field replaceable unit level products and corresponding structural components and cables.
[0019] Furthermore, in step two, the object element refers to something that exists or may exist in the system;
[0020] An object element is represented by a rectangle that includes the object name in the OPD object process diagram.
[0021] Furthermore, in step three, the compositional relationship between the system and its constituent finished products, structural components, and cables is represented by structural links in the OPD object process diagram;
[0022] The structural link symbol is a solid black equilateral triangle, with the apex pointing upwards to connect to the selected aircraft system and the bottom to connect to one or more object elements.
[0023] Furthermore, in step four, the finished product status includes: normal, performance degradation, and fault status; structural components and cables include: normal and damaged status.
[0024] Furthermore, in step five, the normal state of the object element is taken as the input state, and other states are taken as the output state.
[0025] Furthermore, in step six, the state change refers to the change of an object element from its input state to its output state due to the influence of a process, which includes: product malfunction, human-caused damage, and external environmental interference.
[0026] Furthermore, in step seven, the influencing link symbol is a pair of one-way arrows, one of which points from the input state of the object to the process, and the other of which points from the process to the output state of the object.
[0027] The beneficial effects of this invention are:
[0028] An OPM-based aircraft system fault simulation modeling method offers the following advantages: Compared to SysML, OPM models the structure, function, and behavior of complex systems through a unified type view. It employs a "zoom-in" approach to achieve hierarchical modeling, and the unified view facilitates the maintenance of model element consistency, improving modelers' overall understanding of the system. OPM modeling elements are simple, and the modeling method is easy to learn and use, reducing modelers' learning time and improving model development efficiency. This method supports dynamic extrapolation of system fault models, allowing for dynamic correction and verification of the model. Ultimately, it reduces the complexity of simulation analysis and improves the accuracy of system fault simulation prediction. Attached Figure Description
[0029] Figure 1 This is a flowchart illustrating an OPM-based aircraft system fault simulation modeling method.
[0030] Figure 2 This is a diagram illustrating OPD objects, processes, and their impact links;
[0031] Figure 3 This is a schematic diagram of the OPD (Optical Displacement Propagation) fault model for a distributed atmospheric system.
[0032] Figure 4 This is a schematic diagram of the simulation and deduction of the OPD fault model of the distributed atmospheric system. Detailed Implementation
[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.
[0034] This invention proposes an OPM-based aircraft system fault simulation modeling method, such as... Figure 1 As shown, the main steps of the method are as follows:
[0035] Step 1: Select a specific aircraft system, determine the system functions and system composition. The system composition should be broken down to the LRU field replaceable unit level, as well as the corresponding structural components, connecting cables, standard parts, etc.
[0036] Step 2: Determine the OPM modeling object elements based on the finished products and corresponding structural components, connecting cables, standard parts, etc., included in the specific aircraft system. In OPM, an object element refers to something that exists or may exist in the system. The unified type view of OPM—the OPD (Object-Process Diagram)—uses a rectangle containing the object name to represent an object element.
[0037] Step 3: Based on the system functions and finished product modeling object elements of the selected aircraft system, define and create the system's OPD object process diagram. In the OPD, the composition relationship between the system and its included finished products, structural components, cables, etc. is represented by structural links. The graphic symbol for structural links in the OPD is a solid black equilateral triangle with its apex pointing upwards and connected to the whole (i.e., the specified aircraft system), and its bottom connected to one or more object elements (i.e., the finished products, structural components, cables, etc. included in the system).
[0038] Step 4: Specify the status of each object element in the aircraft system to characterize the actual working status of finished products and corresponding structural components, connecting cables, standard parts, etc. Finished product status is typically categorized as normal, faulty, or degraded based on actual usage. Structural components, connecting cables, and standard parts are categorized as normal or damaged.
[0039] Step 5: Select the specified states of each object element in the selected aircraft system as the state values of each object element in OPD. In the fault simulation modeling of aircraft systems based on OPD, it is assumed that the normal state of the object element is used as the input state, and other abnormal states (including faults, damage, performance degradation, etc.) are used as the output states of the object element.
[0040] Step 6: Match the state change process to the stated object elements. According to OPM modeling requirements, the change in object state must originate from the influence of a process, that is, the process transforms the object element from its input state (the state before the process occurs) to its output state (the state after the process occurs). In aircraft system fault simulation modeling, the change from normal to abnormal states of finished products, structural components, and cables in the system may be caused by product malfunctions, human error, or interference from the external environment. Therefore, the state change process of each object element should be matched to the object according to the actual situation.
[0041] Step 7: In OPD, use influence links to connect object states with matching procedures. The symbol for influence links is a pair of one-way arrows, one from the object's input state to the procedure, and the other from the procedure to the object's output state, such as... Figure 2 As shown, the link points from the input state of an object to the process, and then from the process to the output state of the object, representing the transition of an object element in the system from a normal state (input state) to an abnormal state (output state).
[0042] Step 8: Based on the compositional relationships between the finished products in the selected system and their corresponding structural components, connecting cables, standard parts, etc., determine the fault propagation path between object elements in the system. The endpoint of the fault propagation path should be the abnormal state of a certain object element as a direct manifestation of the system fault (such as flashing alarm lights, display prompts, degraded function output, etc.).
[0043] Step 9: According to the fault propagation path between the selected object elements in the system, determine the impact of a change in the state of a certain object element on other object elements in the system, and use the impact link to connect a certain object element in the system from an abnormal state (output state) to the output state of other object elements through a process.
[0044] Step 10: If the selected system fault propagation path points to other systems outside the selected system, then the modeling process of steps 1 to 9 should be repeated for the other systems in the same OPD view until the end of the fault propagation path.
[0045] Step 11: Simulate the completed model to check the rationality and feasibility of the fault model. The simulation during OPD operation shows that the input state gradually fades while the output state gradually becomes solid. At the same time, two red dots appear between the arrows of the two influencing links, moving along the input-output link pair.
[0046] An OPM-based aircraft system fault simulation modeling method offers the following advantages: Compared to SysML, OPM models the structure, function, and behavior of complex systems through a unified type view. It employs a "zoom-in" approach to achieve hierarchical modeling, and the unified view facilitates the maintenance of model element consistency, improving modelers' overall understanding of the system. OPM modeling elements are simple, and the modeling method is easy to learn and use, reducing modelers' learning time and improving model development efficiency. This method supports dynamic extrapolation of system fault models, allowing for dynamic correction and verification of the model. Ultimately, it reduces the complexity of simulation analysis and improves the accuracy of system fault simulation prediction.
[0047] This example illustrates how to perform fault simulation modeling of an aircraft system according to the method described in this invention. The specific implementation steps are as follows:
[0048] Step 1: Specify the distributed atmospheric system (DAS) of a certain type of aircraft. Its main functions include: detecting and collecting local airflow pressure, local airflow angle, and local airflow temperature using multiple sensors mounted on the aircraft nose; compensating and correcting the local atmospheric parameters to output accurate atmospheric parameters to the pilot; and transmitting these accurate atmospheric parameters to the aircraft's navigation system, flight control system, electromechanical control system, engine system, and display control system. The system mainly includes upper / lower angle-of-attack sensors, a main pressure sensor (MPTU), and connecting cables. The upper / lower angle-of-attack sensors transmit the collected data to the MPTU via a bus and are powered by the MPTU.
[0049] Step 2: Specify the upper / lower angle of attack sensors and main pressure sensors (MPTU) in the distributed atmospheric data system as object elements in the atmospheric system fault simulation model.
[0050] Step 3: Create a distributed atmospheric system OPD in the OPCAT environment, and create the upper / lower angle of attack sensors and the main pressure sensor MPTU as object elements in the atmospheric system fault simulation model. At the same time, create structural links (composition relationships) for the upper / lower angle of attack sensors as components of the differential pressure angle of attack measurement system.
[0051] Step 4: Specify the status of each object element in the distributed atmospheric system. Based on the actual fault status of each finished product in the system, determine the upper / lower angle of attack sensor object element, whose status is normal or finished product fault; determine the main pressure sensor MPTU, whose status is normal, finished product fault, or no data received (communication failure).
[0052] Step 5: Based on the finished product object status determined in Step 4, add object status to the upper / lower angle of attack sensor and main pressure sensor MPTU object elements in the distributed atmospheric system OPD. The input status of the upper / lower angle of attack sensor object element is normal, and the output status is finished product fault; the input status of the main pressure sensor MPTU object element is normal, and the output status is fault or no data received.
[0053] Step 6: Match the state change process for the stated object element. The state change process of the upper / lower angle of attack sensor can be considered as non-human-caused damage caused by factors such as product quality or manufacturing process during the use of the finished product. Therefore, the process of changing the state of the upper / lower angle of attack sensor and MPTU object element from normal to faulty is identified as a finished product fault.
[0054] Step 7: Following the process of changing the upper / lower angle of attack sensor object elements as determined in Step 6, add a process in the Distributed Atmospheric System OPD and connect it to the object state using an influence link. The influence link points from the normal state of the upper / lower angle of attack sensor and MPTU object elements to the finished product failure process, and from the finished product failure process to the failure state.
[0055] Step 8: Determine the fault propagation path of the distributed atmospheric system. It is determined that when the upper / lower angle-of-attack sensor malfunctions, communication between it and the main pressure sensor (MPTU) is interrupted, causing the MPTU to fail to receive data and thus report an angle-of-attack fault. Additionally, abnormal electromagnetic interference received by the MPTU can also cause MPTU malfunction, preventing it from receiving data from the angle of attack and resulting in an angle-of-attack fault report. After an angle-of-attack fault is reported, the aircraft's flight control system will illuminate the flight control warning light to indicate that the flight control system cannot receive flight attitude data from the atmospheric system.
[0056] Step 9: Based on the fault propagation path determined in Step 8, determine the impact of the upper / lower angle of attack sensor changing from normal state to fault state on the communication between MPTUs, and connect the fault state of the MPTU through the RS422 communication interruption process.
[0057] Step 10: Since MPTU failures in the atmospheric system affect the alarm status of flight control warning lights in the flight control system, repeat the modeling process from steps 2 to 9 to finally complete the OPD fault model of the distributed atmospheric system fault propagation path, as follows: Figure 3 As shown.
[0058] Step 11: Simulate the completed distributed atmospheric system OPD model to check the rationality and feasibility of the fault model, such as... Figure 4 As shown.
[0059] The above description is merely a specific embodiment of the present invention, providing a detailed description of the invention. Parts not covered herein are conventional techniques. However, the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. The scope of protection of the present invention should be determined by the scope of the claims.
Claims
1. A fault simulation modeling method for aircraft systems based on OPM, characterized in that: The method includes the following steps: Step 1: Select the aircraft system to be simulated and determine its system functions and components; Step 2: Determine the OPM modeling object elements based on the finished products, structural components, and cables included in the selected aircraft system; Step 3: Based on the system functions and finished product objects of the selected aircraft system, define and create the system's OPD object process diagram; Step 4: Specify the status of each object element in the aircraft system to characterize the actual working status of each finished product, structural component, and cable in the system; Step 5: Use the specified state of each object element as the state value of each object element in OPD; Step Six: Match the state change process for stateful object elements; Step 7: Use influence links in OPD to connect the object state to the matching process; Step 8: Determine the fault propagation path between object elements in the selected system based on the composition relationship between the finished products and corresponding structural components and cables. The key to the fault propagation path is the abnormal state of a certain object element as a direct representation of the system fault. Step 9: According to the fault propagation path between the selected object elements in the system, determine the impact of a change in the state of a certain object element on other object elements in the system, and use impact links to connect a certain object element in the system from an abnormal state to the output state of other object elements through a process. Step 10: If the fault propagation path in the selected system points to another system outside the selected system, repeat steps 1 to 9 for the other system in the same OPD view until the end of the fault propagation path. Step 11: Perform simulation and deduction of the fault model to check its rationality and feasibility.
2. The method according to claim 1, characterized in that: In step one, the system components include: finished LRU field replaceable unit level products and corresponding structural components and cables.
3. The method according to claim 2, characterized in that: In step two, the object element refers to something that exists or may exist in the system; An object element is represented by a rectangle that includes the object name in the OPD object process diagram.
4. The method according to claim 3, characterized in that: In step three, the compositional relationship between the system and its constituent finished products, structural components, and cables is represented by structural links in the OPD object process diagram. The structural link symbol is a solid black equilateral triangle, with the apex pointing upwards to connect to the selected aircraft system and the bottom to connect to one or more object elements.
5. The method according to claim 4, characterized in that: In step four, the finished product status includes: normal, performance degradation, and fault status; structural components and cables include: normal and damaged status.
6. The method according to claim 5, characterized in that: In step five, the normal state of the object element is taken as the input state, and other states are taken as the output state.
7. The method according to claim 6, characterized in that: In step six, the state change refers to the change of an object element from its input state to its output state due to the influence of a process, which includes: product malfunction, human-caused damage, and external environmental interference.
8. The method according to claim 7, characterized in that: In step seven, the influencing link symbol is a pair of one-way arrows, one of which points from the input state of the object to the process, and the other points from the process to the output state of the object.