An aircraft hydraulic servo actuation system simulation method based on digital twinning

Abstract

The application discloses an airplane hydraulic servo actuating system simulation method based on digital twinning, and the method comprises the following steps: (1) constructing a digital twinning hydraulic simulation model and a digital twinning three-dimensional visual model of an airplane hydraulic servo actuating system physical system; (2) storing simulation model output data of a monitoring point of the digital twinning hydraulic simulation model and sensor acquisition data of the airplane hydraulic servo actuating physical system in real time and synchronously to form twinning data; (3) comparing and analyzing the simulation model output data and the sensor acquisition data, iteratively optimizing the digital twinning hydraulic simulation model through a model optimization module, and simultaneously performing three-dimensional visual demonstration on the working condition of the airplane hydraulic servo actuating virtual model. The application can provide a simulation modeling and optimization method for airplane hydraulic servo actuating system design, and provide a reference for research and verification of virtual-real mapping technology of the airplane hydraulic servo actuating system based on digital twinning.

Description

Technical Field

[0001] This invention belongs to the field of aircraft hydraulic servo actuation system control, specifically relating to a simulation method for aircraft hydraulic servo actuation systems based on digital twins. Background Technology

[0002] Digital twin technology emphasizes a multi-physics, multi-scale, multi-disciplinary, and multi-probabilistic simulation process. It utilizes the best available models, sensor information, and historical operational data to predict the attributes and behaviors of corresponding physical entities within their lifecycle in virtual space, and features virtual-real fusion, real-time mapping, data-driven operation, and iterative optimization. The aircraft hydraulic servo actuation system is the actuator of the flight control system. Based on instructions from the flight control computer and according to specified static and dynamic requirements, it controls the various control surfaces of the aircraft. Currently, the most widely used flight control system is the hydraulic servo actuation system, which consists of a servo controller and servo actuators.

[0003] Traditional modeling and iteration of aircraft hydraulic servo actuation systems are mainly used in the product development stage. However, once the actual product is developed and installed, its real characteristics often cannot be fully and accurately transferred from the manufacturing end to the design end. As the product is continuously optimized, the deviation between the theoretical model and the physical entity cannot be accurately assessed, and the actual physical state of the product cannot provide optimization support to the design end. This fails to meet the technical research and application needs of utilizing model resources for virtual-real mapping and virtual-real fusion under the development trend of intelligent digital factories.

[0004] In the prior art, Chinese invention patent application number CN202211052645.0, entitled "A System and Method for Maintaining Consistency of Digital Twin Models," discloses a system and method for maintaining consistency of digital twin models, including a consistency determination module, an evolution module, and a consistency verification module. This method proposes a basic idea for model evolution, but it cannot provide a solution for the modeling, iteration, and virtual-real mapping verification process of aircraft hydraulic servo actuation systems. This method provides a detailed description of the simulation modeling method, parameter identification and model optimization process, and 3D dynamic visualization demonstration of digital twin models for aircraft hydraulic servo actuation systems.

[0005] Chinese invention patent application CN201611170699.1, entitled "A Hydraulic Control Method for an Aircraft Servo Actuation System," discloses a hydraulic control method for an aircraft servo actuation system. This method provides a hydraulic over-control logic for the servo actuation system, enabling the servo motor model monitoring to better reflect the health status of the servo motor and eliminating the impact of hydraulic fluctuations on model monitoring. This prevents false alarms caused by transient hydraulic system fluctuations in servo system fault monitoring, which could lead to the shut-off of the SOV solenoid valve. However, this invention does not involve digital twin model simulation, modeling, and iterative optimization methods for aircraft hydraulic servo actuation systems.

[0006] Chinese invention patent application CN201611170699.1, entitled "System for Digital Twin of Hydraulic System," discloses a system for digital twinning a hydraulic system, including a hydraulic system digital twin management terminal, an edge-side detector for connecting to the hydraulic system, and a hydraulic system digital twin cloud. This invention only addresses digital twinning of hydraulic systems and does not involve methods for simulating, modeling, and iteratively optimizing digital twin models of aircraft hydraulic servo actuation systems. Summary of the Invention

[0007] To address this issue, this invention, based on the modeling and simulation technologies behind digital twins, conducts modeling and simulation research on aircraft hydraulic servo actuation systems. Referring to the actual working conditions of the physical aircraft hydraulic servo actuation system, a digital twin hydraulic simulation model and a digital twin 3D visualization model of the physical system are constructed. This allows for continuous modification and iterative optimization of the digital twin hydraulic simulation model, while simultaneously using the simulation model's output data to drive the digital twin 3D visualization model. This virtual-real interaction and real-time mapping ensures the consistency between the virtual model of the aircraft hydraulic servo actuation system, formed by the interconnected digital twin hydraulic simulation model and the physical system, in terms of physics, geometry, motion, and time. Finally, the required pressure, flow rate, and related hydraulic accessory parameters of the aircraft hydraulic servo actuation system are analyzed, predicting the trends of pressure, flow rate, and displacement changes. This provides engineering guidance for the design of aircraft hydraulic servo actuation systems and is beneficial for the research and verification of digital twin-based virtual-real mapping technology.

[0008] The technical solution of the present invention is as follows:

[0009] A simulation method for an aircraft hydraulic servo actuation system based on digital twins includes the following steps:

[0010] Step 1: Referring to the five-dimensional model structure of digital twins, propose an overall scheme architecture for the simulation of aircraft hydraulic servo actuation system based on digital twins, including the physical system of aircraft hydraulic servo actuation system, virtual model of aircraft hydraulic servo actuation system, twin data, service applications, and the connections between the above modules.

[0011] Step 2: Construct a digital twin 3D visualization model of the physical system of the aircraft hydraulic servo actuation system, that is, use 3D modeling software to establish a full-size virtual visualization model of the physical system of the aircraft hydraulic servo actuation system at a full scale.

[0012] Step 3: Construct a digital twin hydraulic simulation model of the physical aircraft hydraulic servo actuation system. This model simulates the hydraulic components of the physical aircraft hydraulic servo actuation system and takes into account factors such as friction, temperature, gas characteristics, and oil in actual working conditions. It dynamically simulates the displacement of the actuator cylinder and the working status of the sensor output of the physical aircraft hydraulic servo actuation system under real working conditions. At the same time, the simulation model output data of the digital twin hydraulic simulation model is used to drive the digital twin three-dimensional visualization model described in Step 2 in real time. The dynamic simulation, prediction, and monitoring of the displacement of the actuator cylinder, sensor output, and aircraft control surface deflection of the aircraft hydraulic servo actuation system are realized through data-driven and virtual reality technologies.

[0013] Step 4: Construct a twin data module to store in real time and synchronously the sensor data collected by the physical system of the aircraft hydraulic servo actuation system and the simulation model output data of the monitoring points of the digital twin hydraulic simulation model;

[0014] Step 5: Establish a communication connection for data interaction, build an Ethernet communication link, and use the TCP / IP protocol for communication.

[0015] Step Six: Construct the service application module, compare and analyze the output data of the simulation model with the data collected by the sensors, iteratively optimize the digital twin hydraulic simulation model through the model optimization module, and at the same time, perform a three-dimensional visualization demonstration of the working status of the aircraft hydraulic servo actuation virtual model.

[0016] The iterative optimization process of the digital twin hydraulic simulation model includes model evaluation, model correction, and model verification.

[0017] Model evaluation assesses the consistency between the physical aircraft hydraulic servo actuation system and its corresponding digital twin hydraulic simulation model. First, a consistency threshold needs to be determined, which is the critical value that ensures the simulation results of the digital twin hydraulic simulation model meet the specified criteria. The sensor data collected by the physical aircraft hydraulic servo actuation system can be denoted as X. T The simulation model output data of the monitoring points of the digital twin hydraulic simulation model can be denoted as Y. T By comparing time series {x t} and {y tThe difference is used to evaluate the consistency of the dynamic performance between the physical system of the aircraft hydraulic servo actuation system and the digital twin hydraulic simulation model. Based on grey relational analysis, the grey relational degree value is obtained between the sensor data collected by the physical system of the aircraft hydraulic servo actuation system and the simulation model output data of the monitoring points of the digital twin hydraulic simulation model. The grey relational degree value is compared with the consistency threshold. If the grey relational degree value is higher than the consistency threshold, it indicates that the digital twin hydraulic simulation model meets the consistency requirements, and the model evaluation result of the digital twin hydraulic simulation model is obtained; otherwise, it does not meet the consistency requirements, and the operation of the model correction module needs to be executed to correct the digital twin hydraulic simulation model.

[0018] Model correction employs a parameter correction method, utilizing actual experimental data from the aircraft hydraulic servo actuation system to identify parameters in the digital twin hydraulic simulation model. Given the excitation signal of the aircraft hydraulic servo actuation system, the displacements of the servo valve core and actuator cylinder are collected under the excitation signal. Based on the collected data and the structure of the digital twin hydraulic simulation model, the LM (Levenberg-Marquardt) algorithm is used to identify system parameters, thereby correcting and optimizing the model, resulting in a parameter-corrected digital twin hydraulic simulation model.

[0019] Model verification involves obtaining the real-time simulation output of the corrected and optimized digital twin hydraulic simulation model and comparing it with the sensor data collected by the physical system of the aircraft hydraulic servo actuation system. The grey relational degree value between the two is calculated based on grey relational analysis. The grey relational degree value is compared with the consistency threshold. If the grey relational degree value is higher than the consistency threshold, the corrected and optimized digital twin hydraulic simulation model meets the consistency requirements. If the grey relational degree value is lower than the consistency threshold, it does not meet the consistency requirements and the model needs to be corrected and optimized again. The final digital twin hydraulic simulation model that meets the requirements after iterative optimization is obtained.

[0020] The construction of the digital twin 3D visualization model includes the following steps:

[0021] Step 1: Use 3D modeling software to create 3D models and assemble the components of the aircraft's hydraulic servo actuation system.

[0022] Step 2: Use model lightweighting technology to lighten the constructed digital twin 3D visualization model;

[0023] Step 3: Integrate and develop the digital twin 3D visualization model, and use a human-computer interaction method to perform 3D visualization demonstration.

[0024] The beneficial effects of this application are as follows: 1) This invention proposes an overall architecture for simulating an aircraft hydraulic servo actuation system based on digital twins. This includes a physical aircraft hydraulic servo actuation system, a digital twin hydraulic simulation model of the physical system, and a digital twin 3D visualization model, forming a virtual model of the aircraft hydraulic servo actuation system, twin data, service application modules, and the connection methods between these modules. The invention also provides a detailed description of the simulation and model optimization iteration method for the aircraft hydraulic servo actuation system based on digital twins. It directly uses data from the aircraft hydraulic servo actuation system under the real aircraft usage context and the digital twin hydraulic simulation model for iteration and optimization, greatly improving the accuracy and usability of the digital twin model. 2) Based on a high-fidelity aircraft hydraulic servo actuation system twin model, under special operating conditions in aircraft development, the model can replace the physical object to complete functions related to the aircraft system, performance checks, fault reproduction, and rapid location. Attached Figure Description

[0025] Figure 1 This is a detailed schematic diagram of the simulation scheme of the aircraft hydraulic servo actuation system based on digital twin according to the present invention.

[0026] Figure 2 This is a schematic diagram of the overall architecture of the simulation of the aircraft hydraulic servo actuation system based on digital twins according to the present invention. Detailed Implementation

[0027] The specific solutions of the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0028] like Figure 1 As shown, this invention proposes a detailed scheme for simulating an aircraft hydraulic servo actuation system based on digital twins. Referring to the five-dimensional model structure of a digital twin, it includes the operation of five modules: physical system, virtual model, twin data, service application, and communication connection.

[0029] In the physical system module, the pilot control command unit controls the flight control computer to send flight control commands to the aircraft's hydraulic servo actuator system. Upon receiving the commands, the electro-hydraulic servo actuators drive the aircraft's control surfaces. During operation, the physical system collects real-time parameters of each electro-hydraulic servo actuator (pressure, flow rate, actuator cylinder displacement, sensor output status) and aircraft control surface motion parameters (control surface position), and transmits these parameters to the twin data module in real time.

[0030] The virtual model is composed of a digital twin hydraulic simulation model and a digital twin 3D visualization model. The digital twin hydraulic simulation model is constructed using AMESim software, where component-level and system-level modeling and simulation are performed on the physical entities of the aircraft's hydraulic servo actuation system, including pumps, servo valves, hydraulic cylinders, and control surfaces. In the MATLAB software environment, the control signals from the flight control computer are converted from digital signals to digital signals using an A / D converter and then used as input to the digital twin hydraulic simulation model. A digital twin 3D visualization model is constructed using SolidWorks and 3DS Max professional 3D modeling software, which virtualizes the hydraulic components of the physical aircraft hydraulic servo actuation system. This virtualization is then integrated and developed using Unity3D software, creating a realistic virtual visualization system for aircraft hydraulic servo actuation. The visualization is driven by data from the digital twin hydraulic simulation model's calculations (including pressure, flow rate, actuator displacement, and control surface position).

[0031] The twin data module stores real-time sensor data collected by the physical system of the aircraft hydraulic servo actuation system and output data of the simulation model of the monitoring points of the digital twin hydraulic simulation model in real time and synchronously, and interacts with the physical system and the virtual model through communication connection.

[0032] Service applications include a 3D visualization dynamic demonstration module for digital twin hydraulic servo actuation systems and an iterative optimization module for digital twin hydraulic simulation models;

[0033] An Ethernet link is established, employing the TCP / IP protocol for communication. This Ethernet connection enables real-time, synchronous data interaction between the physical system, virtual model, digital twin data, and service applications. In the physical system module, sensor data from the aircraft hydraulic servo actuation system is transmitted in real-time to the digital twin data module via the communication connection. Similarly, in the virtual model, simulation output data from the monitoring points of the digital twin hydraulic simulation model is transmitted in real-time to the digital twin data module via the communication connection. The digital twin data module then feeds back the sensor data and simulation model output data to the service application module. The service application module compares and analyzes the received digital twin data through the communication connection, using the real data to refine the virtual model, continuously revising and iteratively optimizing the digital twin hydraulic simulation model, and simultaneously achieving a three-dimensional, dynamic visualization demonstration of the digital twin hydraulic servo actuation system.

[0034] like Figure 2 As shown, the iterative optimization of the digital twin hydraulic simulation model includes the following steps:

[0035] (1) Real-time and synchronous storage of simulation model output data of monitoring points of digital twin hydraulic simulation model and sensor data collected by the physical system of aircraft hydraulic servo actuation system;

[0036] (2) Determine the consistency threshold between the digital twin hydraulic simulation model and the physical aircraft hydraulic servo actuation system; the sensor data collected by the physical aircraft hydraulic servo actuation system can be denoted as X. T The simulation model output data of the monitoring points of the digital twin hydraulic simulation model can be denoted as Y. T To evaluate the consistency between the physical entity of an aircraft's hydraulic servo actuation system and its dynamic performance in a digital twin hydraulic simulation model, it is necessary to compare and analyze the time series {x}. t} and {y t For the digital twin hydraulic simulation model, based on grey relational analysis, a set of pressure or flow data is obtained by simulation with a step size of 0.05 seconds over a certain time period. The amount of data collected by the sensors of the corresponding physical system of the aircraft hydraulic servo actuation system is equal to the amount of data collected by the sensors, and the timing is consistent. Then, the data is preprocessed, and the grey relational degree γ is calculated using the grey relational degree model. k And determine ω1 and ω2, and record the gray relational results obtained after setting the parameters as γ1 and γ2; by formula The gray correlation degree is weighted and averaged to obtain the gray correlation degree value γ. For a fixed resolution coefficient ε, the larger the gray correlation degree value γ, the better the consistency between the simulation data of the digital twin hydraulic simulation model and the sensor data collected by the physical system of the aircraft hydraulic servo actuation system. The gray correlation degree value is compared with the consistency threshold. If the gray correlation degree value is higher than the consistency threshold, it means that the digital twin hydraulic simulation model meets the consistency requirements, and the consistency evaluation result of the digital twin hydraulic simulation model is obtained. Otherwise, it does not meet the consistency requirements and step (3) needs to be performed to correct the digital twin hydraulic simulation model.

[0037] (3) Based on the model evaluation results of the digital twin hydraulic simulation model in step (2), it is necessary to correct the model parameters and use actual test data to identify the parameters of the model; given the excitation signal of the physical system of the aircraft hydraulic servo actuation system, collect the displacement of the servo valve core and the displacement of the actuating cylinder of the hydraulic servo actuation system under the drive of the excitation signal; then, based on the data collected above, on the structure of the digital twin hydraulic simulation model, use the LM (Levenberg-Marquardt) algorithm to identify the system parameters, and then correct and optimize the model; obtain the digital twin hydraulic simulation model after parameter correction;

[0038] (4) Obtain the simulation results of the modified and optimized digital twin hydraulic simulation model and the sensor data collected by the physical system of the aircraft hydraulic servo actuation system, and obtain the gray correlation degree value of the two based on the gray relational analysis method; compare the gray correlation degree value with the consistency threshold. If the gray correlation degree value is higher than the consistency threshold, the modified and optimized digital twin hydraulic simulation model meets the consistency requirements. If the gray correlation degree value is lower than the consistency threshold, it does not meet the consistency requirements and the model needs to be modified and optimized again; obtain the final digital twin hydraulic simulation model that meets the requirements after iterative optimization.

[0039] In the model correction module of the iterative optimization process of the digital twin hydraulic simulation model, parameter correction includes the following steps:

[0040] (1) Monitor the pressure and flow data of hydraulic components such as pump source outlet, solenoid valve, servo motor and actuator cylinder in the simulation process of the digital twin hydraulic simulation model. Combine the sensor data of the aircraft hydraulic servo actuation system physical system collected in real time and synchronously, and compare and verify them through time domain analysis method. If abnormal results are found, proceed to step (2).

[0041] (2) Compare the pressure and flow curves of the corresponding monitoring points of the physical system of the aircraft hydraulic servo actuation system with the digital twin hydraulic simulation model. If the pressure parameter is abnormal, the LM (Levenberg-Marquardt) algorithm is used to identify the relevant parameters and correct the pressure parameter of the model; if the flow parameter is abnormal, the LM (Levenberg-Marquardt) algorithm is used to identify the relevant parameters and correct the pressure parameter of the model.

[0042] (3) After correcting the pressure and flow parameters of the digital twin hydraulic simulation model, the simulation output data of the monitoring points of the digital twin hydraulic simulation model and the sensor data collected by the actual aircraft hydraulic servo actuation system are acquired and compared in real time and synchronously.

[0043] like Figure 2 As shown, the simulation output data of the digital twin hydraulic simulation model drives the digital twin 3D visualization model, thereby realizing a dynamic 3D visualization demonstration of the digital twin hydraulic servo actuation system.

[0044] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. For those skilled in the art, any improvement or substitution of the above embodiments should be covered within the scope of protection of the claims of the present invention.

Claims

1. An aircraft hydraulic servo actuation system simulation method based on digital twinning, characterized in that The method comprises the following steps: Step one, referring to the digital twin five-dimensional model structure, a general scheme architecture of the aircraft hydraulic servo actuation system simulation based on digital twin is proposed, including the aircraft hydraulic servo actuation system physical system, the aircraft hydraulic servo actuation system virtual model, the twin data, the service application and the connection between the above-mentioned modules; Step two, a digital twin three-dimensional visualization model of the aircraft hydraulic servo actuation system physical system is constructed, that is, a full-size virtual visualization model of the aircraft hydraulic servo actuation system physical system is established by using a three-dimensional modeling software; Step three, a digital twin hydraulic simulation model of the aircraft hydraulic servo actuation system physical system is constructed, that is, the hydraulic elements of the aircraft hydraulic servo actuation system physical system are simulated, and the factors of friction, temperature, gas characteristics and oil in the actual working condition are considered, the actuator cylinder displacement of the aircraft hydraulic servo actuation system physical system in the real working environment, the sensor output working state are dynamically simulated, and the simulation model output data of the digital twin hydraulic simulation model are used to drive the digital twin three-dimensional visualization model in step two in real time, so that the dynamic simulation, prediction monitoring of the actuator cylinder displacement, sensor output and aircraft rudder deflection working condition of the aircraft hydraulic servo actuation system are realized by using the data driving and virtual reality technology; Step four, a twin data module is constructed, and the sensor acquisition data of the aircraft hydraulic servo actuation system physical system and the simulation model output data of the monitoring points of the digital twin hydraulic simulation model are stored in real time and synchronously; Step five, a communication connection for data interaction is realized, an Ethernet communication link is established, and a TCP / IP protocol communication is adopted; Step six, a service application module is constructed, the simulation model output data and the sensor acquisition data are compared and analyzed, the digital twin hydraulic simulation model is iteratively optimized through a model optimization module, and the working condition of the aircraft hydraulic servo actuation virtual model is demonstrated in three-dimensional visualization.

2. The aircraft hydraulic servo actuation system simulation method based on digital twinning according to claim 1, characterized in that The optimization process of the digital twin hydraulic simulation model comprises model evaluation, model correction and model verification.

3. The simulation method of the aircraft hydraulic servo actuation system based on digital twinning according to claim 2, characterized in that The model judges the consistency of the aircraft hydraulic servo actuating system physical system and the corresponding digital twin hydraulic simulation model. First, the consistency threshold of the two needs to be determined, which is to ensure that the simulation result of the digital twin hydraulic simulation model meets the critical value. The sensor data collected by the aircraft hydraulic servo actuating system physical system can be recorded as , the simulation model output data of the digital twin hydraulic simulation model monitoring point can be recorded as , the difference between the time series and is compared to judge the consistency of the dynamic performance of the aircraft hydraulic servo actuating system physical system and the digital twin hydraulic simulation model. The gray correlation degree value of the sensor acquisition data of the aircraft hydraulic servo actuation system physical system and the simulation model output data of the monitoring points of the digital twin hydraulic simulation model is obtained based on the gray correlation analysis method, the gray correlation degree value is compared with the consistency threshold value, if the gray correlation degree value is higher than the consistency threshold value, it is indicated that the digital twin hydraulic simulation model meets the consistency requirement, and the model evaluation result of the digital twin hydraulic simulation model is obtained; otherwise, the consistency requirement is not met, and the operation of the model correction module needs to be performed to correct the digital twin hydraulic simulation model.

4. The aircraft hydraulic servo actuation system simulation method based on digital twinning of claim 2, characterized in that The model correction method employs a parameter correction approach. It utilizes actual experimental data from the physical aircraft hydraulic servo actuation system to identify parameters in the digital twin hydraulic simulation model. Given an excitation signal for the physical aircraft hydraulic servo actuation system, it collects the displacement of the servo valve core and the displacement of the actuator cylinder under the excitation signal. Then, based on the collected data and the structure of the digital twin hydraulic simulation model, it uses the Levenberg-Marquardt algorithm (LM algorithm) to identify system parameters, thereby correcting and optimizing the model, resulting in a parameter-corrected digital twin hydraulic simulation model.

5. The simulation method of the aircraft hydraulic servo actuation system based on digital twinning according to claim 2, characterized in that The specific method for model verification is to obtain the real-time simulation output of the corrected and optimized digital twin hydraulic simulation model, and the sensor data collected by the physical system of the aircraft hydraulic servo actuation system, and to obtain the grey relational degree value between the two based on the grey relational analysis method. The gray correlation value is compared with the consistency threshold. If the gray correlation value is higher than the consistency threshold, the corrected and optimized digital twin hydraulic simulation model meets the consistency requirements. If the gray correlation value is lower than the consistency threshold, it does not meet the consistency requirements and the model needs to be corrected and optimized again. The final digital twin hydraulic simulation model that meets the requirements after iterative optimization is obtained.

6. The aircraft hydraulic servo actuation system simulation method based on digital twinning according to claim 1, characterized in that The construction of the digital twin 3D visualization model includes the following steps: Step 1: Use 3D modeling software to create 3D models and assemble the components of the aircraft's hydraulic servo actuation system. Step 2: Use model lightweighting technology to lighten the constructed digital twin 3D visualization model; Step 3: Integrate and develop the digital twin 3D visualization model, and use a human-computer interaction method to perform 3D visualization demonstration.

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