Aircraft landing gear folding and unfolding function control logic integration simulation verification method

Abstract

The invention belongs to the field of aircraft landing gear simulation design, and particularly relates to an aircraft landing gear folding and unfolding function control logic integrated simulation verification method, which comprises the following steps: carrying out functional architecture decomposition on an aircraft landing gear folding and unfolding function control logic, and respectively carrying out activity process analysis on an aircraft landing gear folding scene and an aircraft landing gear unfolding scene; determining all function modules related to all the activity processes; determining all function systems corresponding to the function module, and performing function distribution; and a control panel is arranged, so that a function control logic process in an image-text expression mode is converted into a visual model dynamic control process for design, and communication and understanding among engineers are facilitated. Defects and omissions in the design process, the cost of later product tests and the number of iterations are reduced, the airplane design and verification efficiency can be greatly improved, and consumption of various resources by designers in the project design process is reduced.

Description

Technical Field

[0001] This application belongs to the field of aircraft landing gear simulation design, and particularly relates to a method for integrated simulation verification of the control logic of the aircraft landing gear retraction / extension function. Background Art

[0002] The aircraft landing gear is one of the very important systems on an aircraft, responsible for supporting the weight of the aircraft during ground operation and takeoff / landing. Its design and operation must meet strict safety standards to ensure the safe takeoff / landing and ground operation of the aircraft. In order to optimize the functional design of the landing gear, improve its performance and efficiency, discover and solve potential design problems before actual manufacturing, and reduce the late correction cost, it is necessary to conduct simulation analysis and verification on the landing gear during the design stage.

[0003] The simulation of the aircraft landing gear retraction / extension function can be carried out through various methods. Although there have been many research results on the simulation of the landing gear currently, most of them focus on the mechanical property simulation. By establishing a mathematical model of the landing gear and using computer software for simulation analysis to simulate the performance of the landing gear under different working conditions, such as dynamic simulation for analyzing the motion characteristics of the landing gear at different stages such as takeoff, landing, and taxiing, structural strength simulation for evaluating the strength and stiffness performance under different working conditions, flight dynamics simulation for analyzing the impact of the landing gear on the flight performance of the aircraft, comfort simulation for evaluating the comfort performance of the landing gear. In addition, there are also methods such as analyzing landing gear failures based on co-simulation.

[0004] However, in the initial design stage, there is still a lack of integrated simulation verification for the control logic of the aircraft landing gear retraction / extension function. The landing gear retraction / extension control function belongs to the complex functions of an aircraft, which involves multiple aircraft systems, including the flight management subsystem, flight control subsystem, hydraulic subsystem, etc. The signals between the systems are intricate, the cross-link interfaces are dense, and effective communication and coordination are required between the systems. To verify their coordinated operation in the entire landing gear system, it is usually necessary to conduct integration on the ground test bench after each system has been verified separately to complete the comprehensive verification work of multiple aircraft systems to ensure that the aircraft landing gear can operate normally under various working conditions and meet the safety standards. In the early design stage, these complex relationships are usually only described in words in the design documents, and often such complex logical relationships are difficult to be clearly and completely expressed in pictures and texts, lacking a simulation method for visualizing the integrated verification of the control logic. Summary of the Invention

[0005] The purpose of this application is to provide a method for integrated simulation verification of the control logic of the aircraft landing gear retraction / extension function to solve the problem of visual expression of the control logic of the aircraft landing gear retraction / extension function in the prior art.

[0006] The technical solution of this application is: a method for integrated simulation verification of the control logic of the landing gear retraction and extension function, including: Decompose the functional architecture of the landing gear retraction and extension control logic, analyze the activity processes for the landing gear retraction and extension scenarios respectively, and determine all functional modules involved in all activity processes; determine all functional systems corresponding to the functional modules, perform functional allocation, determine the functional systems participating in each activity process and the corresponding interfaces and interaction events, and form a document file; Establish a control logic model based on the document file, conduct interaction analysis between systems through the control logic model, analyze events and interfaces, and determine the cross-linking relationships between physical systems; Connect the functional logics between systems according to the cross-linking relationships between physical systems, conduct state analysis, and evaluate the rationality and correctness of the system functional logics until all functional logics pass the evaluation; Set up a control panel, and respectively set different spaces for different systems on the control panel, add different buttons and simulation operation handles, and set LED lights to display prompt information and fault simulation situations during the simulation process; Bind the parameters under the cockpit system to the controls on the control panel, and transmit them to the power supply system, hydraulic system, flight management system, and landing gear through interface events, and finally transmit the execution results back to the cockpit system to form a state diagram; Input different environmental conditions for simulation verification, observe the state transition process of the state diagram and the display of the control panel, and verify the correctness and effectiveness of the state transition conditions and actions until the verification is completed.

[0007] Preferably, the specific method for analyzing the activity processes for the landing gear retraction and extension scenarios is: Identify the core functions of all systems of the landing gear, and then decompose and allocate the core functions of the systems. The core functions of each system include: the cockpit system is responsible for issuing control instructions and displaying states; the flight management subsystem is responsible for calculating, judging, and sending instructions; the hydraulic system is responsible for providing the energy for the landing gear retraction and extension; Obtain the system data in the processes of landing gear retraction and extension, define the interfaces and interaction events between systems in the processes of landing gear retraction and extension, and form a document file.

[0008] Preferably, the interaction analysis includes: various state analyses of the system, events and conditions triggering state transitions, and design of the control display panel; establish a state diagram and add transition conditions and actions between states, and describe the transition conditions and actions between each state.

[0009] Preferably, the description of the transition conditions and actions between each state includes: Power supply system: Supply power to each system; Cockpit system: The cockpit system is divided into an initial state and an operating state. After the power supply system supplies power, it jumps from the initial state to the operating state, and sends commands to the flight management system in the operating state; Flight management system: The flight management system is divided into three states: receiving commands, solving, and sending commands; after receiving commands and through solving, it sends commands to the hydraulic system; Hydraulic system: The solenoid valve of the hydraulic system has two states: open and closed. When the solenoid valve of the hydraulic system is open, it provides pressure to the landing gear; Landing gear: The states of the landing gear are the state during lowering, the lowered state, the state during retraction, and the retracted state.

[0010] Preferably, the control logic model is established using SysML.

[0011] Preferably, the control panel is specifically designed as follows: Two buttons, "Retract" and "Lower", are set on the control panel; An LED light is set. The LED light is initially off. If a valid signal is received, the LED light shows green. If an invalid signal is received, the LED light flashes red; the final state of the landing gear is displayed in text; Different buttons are set to simulate fault conditions.

[0012] The method for integrated simulation verification of the control logic of the landing gear retraction and extension function of the present application converts the functional control logic process in the form of text and graphics into a visual model dynamic control process for design, which helps communication and understanding among engineers. It reduces defects and omissions in the design process, the cost of later product tests, and the number of iterations, can greatly improve the efficiency of aircraft design and verification, and reduce the consumption of various resources by designers during the project design process. Brief Description of the Drawings

[0013] In order to more clearly illustrate the technical solutions provided by the present application, the drawings will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application.

[0014] Figure 1 It is a schematic diagram of the overall process of the present application; Figure 2 It is a state diagram of the power supply system of the present application. Detailed Embodiments

[0015] Next, in combination with the accompanying drawings in the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0016] A method for integrated simulation verification of the control logic of the retraction and extension function of an aircraft landing gear, as Figure 1 shown, includes the following steps: Step S100, decompose the functional architecture of the control logic of the retraction and extension function of the landing gear, analyze the activity processes of the landing gear retraction and extension scenarios respectively, and determine all functional modules involved in all activity processes; determine all functional systems corresponding to the functional modules, perform function allocation, and determine the functional systems participated in by each activity process and the corresponding interfaces and interaction events, and form a document file.

[0017] The control logic of the retraction and extension function of the landing gear mainly includes the generation of the retraction and extension commands of the landing gear, the control and monitoring of the retraction and extension actuators of the landing gear, and the feedback and display of the retraction and extension states of the landing gear. The landing gear function is divided into the landing gear retraction logic and the landing gear extension logic.

[0018] When the flight management system receives the "retract" instruction of the landing gear sent by the cockpit system, it first generates the retraction instructions for the nose landing gear and the left and right landing gears, and retracts the nose landing gear and the left and right landing gears through hydraulic drive; when the in-place signals for the retraction of the nose landing gear, the left landing gear, and the right landing gear are collected, it issues a control instruction to retract the landing gear doors. During the process of retracting the landing gear, the retraction process of the landing gear is continuously sent to the cockpit system for displaying the current retraction state of the landing gear.

[0019] After the flight management system receives the "extend" instruction of the landing gear, it first executes the opening of the nose landing gear door and the front door of the main landing gear. Only after the nose landing gear door and the front door of the main landing gear both give the in-place signals for extension can the actions of extending the nose landing gear and the main landing gear be executed. When the main landing gear is extended in place, the front door of the main landing gear executes the retraction action until the in-place signal for the closing of the front door of the main landing gear is collected. When the in-place signals for the extension of the nose landing gear and the main landing gear are collected, it gives a display of the landing gear being extended in place to the cockpit.

[0020] During the flight of the aircraft, the power supply system supplies power to each system of the aircraft. After power-on, when the "retract" switch is pressed, the switch instruction is sent to the flight management system. After calculation and judgment, the flight management computer can issue an instruction to the hydraulic system to provide energy for the landing gear system, and first lower the front door of the main landing gear. Only after the front doors of the main landing gears both give the in-place signals for extension can the nose landing gear and the main landing gear be retracted.

[0021] Preferably, the specific method for analyzing the activity process of the landing gear retraction and extension scenarios is as follows: 1. Identify the core functions of all systems of the landing gear, and then decompose and allocate the core functions of the systems. The core functions of each system include: the cockpit system is responsible for issuing control instructions and displaying status; the flight management subsystem is responsible for calculating, judging, and sending instructions; the hydraulic system is responsible for providing the energy for landing gear retraction and extension. 2. Obtain the system data of each system in the landing gear retraction and extension processes, define the interfaces and interaction events between the systems in the landing gear retraction and extension processes, and form a document file, as Figure 2 shown.

[0022] Step S200, establish a control logic model according to the document file, perform interaction analysis between systems through the control logic model, analyze events and interfaces, and determine the cross-linking relationship between physical systems.

[0023] The interaction analysis includes: various state analyses of the system, events and conditions that trigger state transitions, and design of the control display panel; establish a state diagram and add transition conditions and actions between states, and describe the transition conditions and actions between each state.

[0024] Describing the transition conditions and actions between each state includes: Power supply system: Send instructions to supply power to each system, as Figure 2 shown, where idle represents the built-in development and learning environment, the instruction sent to the flight management system is evPowerToCS, the instruction sent to turn on the warning display light is evA1armToCS, and the instruction sent for landing gear status display is evStateToCS.

[0025] Cockpit system: The cockpit system is divided into an initial state and a working state. After being powered by the power supply system, it jumps from the initial state to the working state. In the working state, it sends instructions to the flight management system, and the flight management system judges whether to give an alarm or display the landing gear status.

[0026] Flight management system: The flight management system is divided into three states: receiving instructions, calculating, and sending instructions. After receiving instructions and performing calculations, it sends instructions to the hydraulic system.

[0027] Hydraulic system: The solenoid valve of the hydraulic system is divided into two states: open and closed. When the solenoid valve of the hydraulic system is open, it provides pressure to the landing gear.

[0028] Landing gear: The states of the landing gear include the state during the lowering process, the lowered state, the state during the retraction process, and the retracted state. During the lowering process, first lower the main landing gear and nose landing gear doors. After completion, send a message to the flight management system, which, after making a judgment, sends an instruction to lower the main landing gear and nose landing gear doors. After lowering in place, jump to the lowered state.

[0029] Preferably, the control logic model is established using SysML.

[0030] Step S300: Connect the functional logics between systems according to the cross-linking relationships between physical systems, conduct state analysis, and evaluate the rationality and correctness of the system functional logics until all functional logics pass the evaluation.

[0031] Step S400: Set up a control panel, and respectively set different spaces on the control panel for different systems, add different buttons and simulated operating handles, and set LED lights to display the prompt information and fault simulation situations during the simulation process; The specific design of the control panel is as follows: 1. Set two buttons, "Retract" and "Lower", on the control panel to simulate the control instructions of the cockpit; 2. Set LED lights to display various states during the retraction process of the landing gear and doors. The initial state of the LED lights is off. If a valid (in-place) signal is received, the LED lights will display green. If an invalid (in-place) signal is received, the LED lights will flash red. The final state of the landing gear is displayed in text.

[0032] 3. Set different buttons to simulate various fault situations.

[0033] Step S500: Bind parameter values, bind the parameters under the cockpit system to the controls on the control panel, and transfer them to the power supply system, hydraulic system, flight management system, and landing gear through interface events. Finally, send the execution result back to the cockpit system to form a state diagram, so that the retraction and extension states of the landing gear can be displayed on the control panel.

[0034] Step S600: Conduct simulation verification, input different environmental conditions for simulation verification, observe the state transition process of the state diagram and the display of the control panel, and verify the correctness and effectiveness of the state transition conditions and actions until the verification is completed.

[0035] Through the above design, the functional control logic process in the form of graphic and text expressions is converted into a visual model dynamic control process for design, which helps the communication and understanding among engineers. It reduces the defects and omissions in the design process, the costs of later product tests, and the number of iterations, can greatly improve the efficiency of aircraft design and verification, and reduce the consumption of various resources by designers during the project design process.

[0036] Finally, it should be noted that: in the accompanying drawings of the disclosed embodiments of the present invention, only the structures related to the disclosed embodiments are involved. For other structures, reference can be made to the general design. Without conflict, the same embodiment and different embodiments of the present invention can be combined with each other; Finally, the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for integrated simulation verification of the control logic for the retraction and extension of an aircraft landing gear, characterized in that, Including: Conduct functional architecture decomposition on the control logic of the landing gear retraction and extension functions, analyze the activity processes for the landing gear retraction and extension scenarios respectively, and determine all functional modules involved in all activity processes; Determine all functional systems corresponding to the functional modules, conduct functional allocation, determine the functional systems participating in each activity process and their corresponding interfaces and interaction events, and form a document file; Establish a control logic model based on the document file, conduct interaction analysis between systems through the control logic model, analyze events and interfaces, and determine the cross-linking relationships between physical systems; Connect the functional logics between systems according to the cross-linking relationships between physical systems, conduct state analysis, and evaluate the rationality and correctness of the system functional logics until all functional logics pass the evaluation; Set up a control panel, and set different spaces corresponding to different systems on the control panel, add different buttons and simulated operating handles, and set LED lights to display prompt information and fault simulation situations during the simulation process; Bind the parameters under the cockpit system to the controls on the control panel, and transmit them to the power supply system, hydraulic system, flight management system, and landing gear through interface events, and finally transmit the execution results back to the cockpit system to form a state diagram; Input different environmental conditions for simulation verification, observe the state transition process of the state diagram and the display of the control panel, and verify the correctness and effectiveness of the state transition conditions and actions until the verification is completed.

2. The method for integrated simulation verification of the control logic for the retraction and extension of an aircraft landing gear according to claim 1, characterized in that, The specific method for analyzing the activity processes for the landing gear retraction and extension scenarios is: Identify the core functions of all systems of the landing gear, and then decompose and allocate the core functions of the systems. The core functions of each system include: the cockpit system is responsible for issuing control instructions and displaying states; the flight management subsystem is responsible for calculation, judgment, and sending instructions; the hydraulic system is responsible for providing energy for landing gear retraction and extension; Obtain the data of each system in the processes of landing gear retraction and extension, define the interfaces and interaction events between systems in the processes of landing gear retraction and extension, and form a document file.

3. The method for integrated simulation verification of the control logic for the retraction and extension of an aircraft landing gear according to claim 1, characterized in that, The said interaction analysis includes: various state analyses of the system, events and conditions triggering state transitions, and design of the control display panel; establish a state diagram and add transition conditions and actions between states, and describe the transition conditions and actions between each state.

4. The method for integrated simulation verification of the control logic for the retraction and extension of an aircraft landing gear according to claim 3, characterized in that, Describing the transition conditions and actions between each state includes: Power supply system: Supply power to each system; Cockpit system: The cockpit system is divided into an initial state and a working state. After being powered by the power supply system, it jumps from the initial state to the working state, and sends instructions to the flight management system in the working state; Flight management system: The flight management system is divided into three states: receiving instructions, calculating, and sending instructions; receives instructions, calculates, and then sends instructions to the hydraulic system; Hydraulic system: The solenoid valve of the hydraulic system has two states: open and closed. When the solenoid valve of the hydraulic system is open, it provides pressure to the landing gear; Landing gear: The states of the landing gear are in the process of lowering, lowered state, in the process of retracting, and retracted state.

5. The method for integrated simulation verification of the control logic for the retraction and extension of an aircraft landing gear according to claim 3, characterized in that: The said control logic model is established using SysML.

6. The method for integrated simulation verification of the control logic for the retraction and extension of an aircraft landing gear according to claim 1, characterized in that, The specific design of the said control panel is: Set two buttons, "Retract" and "Extend", on the control panel; An LED light is set. The LED light is initially off. If a valid signal is received, the LED light shows green. If an invalid signal is received, the LED light blinks red; the final state of the landing gear is displayed in text. Different buttons are set to simulate fault conditions.

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