Flight simulators and integrated quality assessment methods for helicopters of various configurations

Abstract

This invention provides a multi-configuration helicopter quality assessment simulator and flight simulation method, belonging to the field of flight simulators. The flight simulator of this invention includes: a hardware system: a six-degree-of-freedom motion platform, a joystick system, multiple computers, and displays; and a software system: a flight simulation system, a comprehensive simulation management platform, a virtual central control console, a visual display system, and a flight quality assessment system. This simulator covers a wide range of helicopters, from traditional single-rotor helicopters with tail rotors to innovative coaxial rigid rotor helicopters, tiltrotor aircraft, tandem helicopters, and the X-3 compound high-speed helicopter. It supports both offline and human-in-the-loop modes to achieve rapid flight simulation for various flight missions, enabling timely flight quality assessment using simulation data and providing reference suggestions for the formulation of flight quality specifications and the setting of flight missions for emerging helicopter configurations.

Description

Technical Field

[0001] This invention belongs to the field of flight simulators, and more specifically, relates to a flight simulator for helicopters of various configurations, which is equipped with an integrated flight quality assessment interface. Background Technology

[0002] Helicopters, due to their unique flight characteristics such as vertical takeoff and landing, hovering, and low-speed / high-speed flight, have important applications in both military and civilian fields. The technical requirements and research focus have shifted from solely pursuing high flight performance indicators to prioritizing mission completion capabilities and piloting quality levels, such as stability and handling characteristics—in other words, flight quality. Currently, flight quality assessment primarily employs three technical methods: computational analysis, flight simulation, and flight testing. Computational analysis and flight simulation, through helicopter flight simulators, enable visualization of visual scenes and motion. As a crucial enabling technology in the aviation field, helicopter flight simulators hold significant application prospects in personnel training, engineering research, and science popularization.

[0003] Domestic universities have also conducted extensive research in helicopter flight simulators. For example, the Civil Aviation University of China, Shenyang Aerospace University, and Nanjing University of Aeronautics and Astronautics have carried out flight simulation dynamics modeling and flight simulation system construction for small unmanned helicopters. Beijing University of Aeronautics and Astronautics developed a pilot robot prototype based on flight simulation verification and completed flight test verification on an SVH-4 helicopter. Furthermore, in terms of helicopter simulator products, models equipped with VR visuals and six-degree-of-freedom motion tables, such as the R44-D6 and S300CBi, can only be used for flight simulation of single-rotor helicopters with tail rotors. Simulators suitable for helicopter teaching and research are equipped with joystick systems and visual systems, but lack multi-degree-of-freedom haptic experiences, as well as offline / on-loop simulation switching and evaluation functions.

[0004] Regarding the current state of technological development, the main problems are as follows:

[0005] (1) The development of helicopter simulators in China started late, and there is a certain gap between China and foreign countries in terms of product maturity and simulation realism.

[0006] (2) Domestic simulators are mainly designed for military helicopter models. The development cycle is long and the cost is high. Simulators for civilian use mainly rely on imports, and the price and maintenance costs are very high.

[0007] (3) At present, helicopter six-degree-of-freedom motion simulators are mainly developed for single-rotor helicopters with tail rotors, and lack the expandability of helicopter configurations; while helicopter simulators suitable for scientific research and teaching mostly lack the haptic experience of multiple degrees of freedom.

[0008] (4) Apart from single-rotor helicopters with tail rotors, other types of rotorcraft are developing rapidly. However, the development of simulation and evaluation simulators for rotorcraft is lagging behind and cannot meet the needs of new configurations. In addition, new configuration rotorcraft, especially those designed for high speed and distributed power, require more matching quality specifications. Summary of the Invention

[0009] To address the aforementioned issues, this invention provides a helicopter flight simulator equipped with a multi-configuration helicopter flight simulation and quality assessment simulation system. This simulator covers a wide range of helicopters, from traditional single-rotor helicopters with tail rotors to innovative coaxial rigid rotor helicopters, tiltrotor aircraft, tandem helicopters, and the X-3 compound high-speed helicopter. It supports both offline and human-in-the-loop modes to achieve rapid flight simulation and flight quality assessment for various flight missions. It can perform integrated and comprehensive simulation and assessment of helicopter flight quality, including but not limited to key indicators such as flight stability, handling, and response characteristics. It also provides reference suggestions for the formulation of flight quality specifications and the setting of flight missions for emerging helicopter configurations.

[0010] This invention is implemented as follows:

[0011] A flight simulator for various helicopter configurations is characterized by its ability to achieve offline and human-in-the-loop flight simulation and integrated flight quality assessment for various helicopter configurations through hardware and software systems. The simulator includes a hardware system and a software system: the software system includes a flight simulation system, an integrated simulation management platform, a visual display system, a virtual central control console, and a flight quality assessment system.

[0012] The integrated simulation management platform, using LabVIEW software, integrates sub-VIs for model selection, data monitoring, basic control law parameter setting, control input setting, offline panel setting, in-loop simulation setting, in-loop control panel / instrumentation, and data storage. It enables helicopter configuration selection, initial trim speed selection, and flight data monitoring. The integrated simulation management platform transmits helicopter motion and status parameters to the visual system, flight quality evaluation system, and six-degree-of-freedom motion platform via UDP protocol.

[0013] The aforementioned visual display system includes 3D models of helicopters of different configurations, runways, and virtual scene models of maneuvering subjects, and can generate simulated scene images of helicopter motion and external flight that match the motion and state parameters.

[0014] The virtual central control console relies on LabVIEW software and touch screen hardware to simulate the control buttons, knobs, switches and instrument displays in the cockpit. When the pilot is conducting human-in-the-loop flight simulation, he can turn the control mode and the auxiliary driving function on and off through the knobs and buttons.

[0015] The flight quality assessment system described above, combined with offline simulation data such as AB arrays and human-in-the-loop simulation data such as control response, can be used for quantitative assessment of flight quality parameters such as bandwidth and phase delay, stability, inter-axis coupling, speed, large attitude changes, and collective pitch control response in hovering and low-speed states, and forward flight states.

[0016] The six-degree-of-freedom motion platform can be equipped with a visual display system, a virtual central control console, foot pedals (3), a collective pitch control stick, a side control stick, a central control stick, an integrated simulation management platform, and an acoustic simulation system. The lower computer of the six-degree-of-freedom motion platform receives the three-axis attitude angle, angular velocity, angular acceleration, fuselage position, three-axis body speed, ground speed, acceleration, fuselage angle of attack, sideslip angle, climb angle, and overload parameters generated by the integrated simulation management platform, and feeds them back to the motion platform and the driver through the extension and retraction of the electric cylinder.

[0017] Furthermore, the hardware system includes two computers, five displays, a joystick system, a six-degree-of-freedom motion platform, and a control cabinet. The two computers are a visual display computer and a simulation management computer. The visual display computer is connected to three 34-inch curved displays, providing a field of view of 155° horizontally and 55° vertically, offering the pilot a continuous and complete external view. The simulation management computer is connected to a 27-inch display and a 27-inch touchscreen. The 27-inch display houses the integrated simulation management platform, and the 27-inch touchscreen houses the virtual central control console.

[0018] The control stick system includes foot pedals, a collective pitch stick, a side stick, and a center stick. Both the side stick and the center stick can achieve lateral and longitudinal cyclic pitch control, while the simulator uses the center stick. The stick trim and release functions are set via the buttons on the collective pitch stick, side stick, and center stick, which assists the pilot in flying the helicopter.

[0019] The six-degree-of-freedom motion platform is equipped with a joystick system, three visual displays, a 27-inch touch screen, and a driver's seat. The control cabinet controls the telescopic movement of six electric cylinders to achieve the pitch, roll, yaw, longitudinal, lateral, and vertical movements of the entire motion platform.

[0020] The integrated simulation management platform includes a simulation management module, a flight control monitoring module, and a data monitoring module.

[0021] Furthermore, the helicopter flight simulator uses the following data communication method:

[0022] The flight simulation system, visual simulation system, and six-degree-of-freedom motion platform achieve data transmission between hardware systems via USB / HDMI and data communication between software systems via UDP protocol. This allows the flight attitude, flight position, and flight speed status information to be fed back to the visual and motion platforms, and then to the pilot.

[0023] The flight simulation system, integrated simulation management platform, joystick system, and virtual central control console synchronize and transmit data through LabVIEW local variables and multithreading.

[0024] The flight simulation system stores flight simulation data and flight quality assessment data in a queue format for flight simulation status monitoring and subsequent helicopter flight quality assessment.

[0025] The helicopter flight simulator employs a unified modular data interface. The helicopter flight control system simulation model includes a joystick input module, a control panel input module, a helicopter flight status input module, a flight control stick output module, and a flight control panel output module. The helicopter flight mechanics model includes a flight control stick input module and a flight status output module. For different helicopter configurations, rapid switching of the simulation interface for the corresponding configuration can be achieved without extensive modifications to the backend data interface of the integrated simulation management platform.

[0026] In the integrated quality evaluation method for helicopter flight simulators with multiple configurations in this invention, the helicopter flight simulator can be used for both offline simulation and human-in-the-loop simulation. Both offline simulation and human-in-the-loop simulation include three common steps: model selection, basic control law parameter setting, and data storage.

[0027] Model selection: Select the helicopter flight mechanics model and the helicopter flight control system simulation model dll files respectively, and use the MIT (Model Interface Toolkit) toolbox to realize the recognition and calling of the models in the LabVIEW integrated simulation management platform;

[0028] Basic control law parameter settings: Read the flight control parameter file and input it as an array into the helicopter flight control system simulation model. Select manual mode to modify the control parameters, and click save file to save the newly modified control parameters.

[0029] Data storage: Set the write frequency and use the queue operation in the LabVIEW program panel to save the helicopter flight data to a new file;

[0030] There are some differences between offline and human-in-the-loop simulations in flight simulation. Offline flight simulation requires pre-setting the working mode, response type of each channel, assisted driving functions, and control inputs before the simulation. Human-in-the-loop simulation, on the other hand, needs to consider the real-time performance of the simulation more.

[0031] Furthermore, for offline simulation, the flight simulation steps are as follows:

[0032] Offline panel settings: Pre-set the main flight control functions and working mode selection, automatic flight control function and boundary protection function. If you need to switch, select "Switch" and set the switching time and the mode after switching.

[0033] Offline control input settings: By using piecewise functions, step, square wave, dipole, frequency sweep and sine signals are generated for each channel, and single-channel or multi-channel signals can be combined.

[0034] For human-in-the-loop flight simulation, the flight simulation steps are as follows:

[0035] The control instrument input allows for functions similar to those on the offline panel to be performed via a virtual central control panel. Here, control modes are switched in real time using knobs, buttons, and switches, and the status of the Boolean indicator light below the button shows whether the control mode has been switched.

[0036] Real-time control input is achieved by connecting external foot pedals, collective joysticks, side joysticks, and center joysticks to the LabVIEW program panel, converting joystick displacement into lever stroke in the model.

[0037] In-Loop Simulation Settings: Configure the IP addresses and UDP data write ports for the visual computer and simulator slave device, and enable the simulation visuals and six-degree-of-freedom motion platform during human-in-the-loop simulation.

[0038] Furthermore, based on flight simulation, it can be directly used for integrated flight quality parameter evaluation. The method for quantitative parameter evaluation of helicopter flight quality is as follows:

[0039] Step 1: Select the flight state and evaluation parameters to be evaluated; Step 2: Read the AB array, transfer function, txt, and mat data files; Step 3: Select the channel to be evaluated, i.e., display the eigenvalues, time-domain response curve, and frequency-domain response curve; Step 4: Display the evaluation results and automatically generate them in a table; Step 5: Exit the evaluation and select other parameters for the next evaluation step.

[0040] The advantages of this invention compared to the prior art are as follows:

[0041] This invention provides a simplified helicopter flight simulator for multi-configuration helicopter flight simulation and integrated flight quality assessment, covering everything from traditional single-rotor helicopters with tail rotors to innovative coaxial rigid rotor helicopters and tiltrotor aircraft, effectively saving simulator manufacturing costs and development cycles. Due to the use of modular modeling methods and a unified data interface in flight mechanics and flight control system modeling, the flight simulation system has strong reusability and scalability, supporting simulation of different flight missions for the same helicopter and allowing the addition of more new helicopter configurations to the model library. This helicopter flight simulator combines offline simulation and human-in-the-loop simulation. Through typical handling responses, iterative simulation of control parameters, and virtual simulation of maneuvers, it can effectively identify and correct conceptual errors in the preliminary design stage of helicopters, especially new configurations, assisting in the design and verification of helicopter mathematical models. Furthermore, it can utilize offline / human-in-the-loop flight simulation data to perform quantitative parameter assessment of flight quality, ensuring that the constructed helicopter model meets the requirements of the corresponding level, and providing a data foundation and reference suggestions for the formulation of flight quality specifications for new helicopter configurations and the setting of special flight missions. Attached Figure Description

[0042] Figure 1 A schematic diagram of a six-degree-of-freedom motion platform for a helicopter flight simulator motion device provided in an embodiment of the present invention;

[0043] Figure 2 This is a schematic diagram of the structure of the flight simulation and evaluation system provided in the embodiments of the present invention;

[0044] Figure 3 A schematic diagram of the flight simulation interface of the integrated simulation management platform provided in this embodiment of the invention;

[0045] Figure 4 This is a schematic diagram of the structure of the virtual control platform component provided in an embodiment of the present invention;

[0046] Figure 5 A schematic diagram of the structure of an example helicopter (single-rotor helicopter with tail rotor) for the helicopter flight mechanics model component provided in the embodiments of the present invention;

[0047] Figure 6 This is a schematic diagram of the structure of a helicopter flight control system component provided in an embodiment of the present invention;

[0048] Figure 7 A flowchart for evaluating hovering bandwidth and phase delay provided in an embodiment of the present invention.

[0049] The components are: 1-Visual display system, 2-Virtual central control console, 3-Foot pedals, 4-Collective pitch joystick, 5-Side joystick, 6-Center joystick, 7-Electric cylinder; 21-Simulation management module, 22-Flight control monitoring module, 23-Flight data monitoring module. Detailed Implementation

[0050] To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the following examples provide a more detailed description of the invention. It should be noted that the specific embodiments described herein are merely illustrative and not intended to limit the scope of the invention.

[0051] like Figures 1-2 As shown, the helicopter flight simulator of the present invention includes: a hardware system: a six-degree-of-freedom motion platform, a joystick system, multiple computers and displays; and a software system: a flight simulation system, an integrated simulation management platform, a visual display system, a virtual central control console 2, and a flight quality assessment system.

[0052] The aforementioned visual display system 1 includes 3D models of helicopters of different configurations, runways, and virtual scene models of maneuvering subjects. Combined with three 34-inch curved displays, it can generate simulated scene images of helicopter motion and external flight that match the motion and state parameters.

[0053] The control system includes foot pedals 3, collective pitch control stick 4, side control stick 5, and center control stick 6. Both the side control stick 5 and the center control stick 6 can achieve lateral and longitudinal cyclic pitch control. The simulator uses the center control stick 6. The stick trim and stick release functions can be set via the upper buttons on the collective pitch control stick 4, side control stick 5, and center control stick 6, which can assist the pilot in flying the helicopter.

[0054] The six-degree-of-freedom motion platform is equipped with a joystick system, three visual displays, a 27-inch touch screen, and a driver's seat. The control cabinet controls the telescopic movement of six electric cylinders to achieve the pitch, roll, yaw, longitudinal, lateral, and vertical movements of the entire motion platform.

[0055] like Figure 3 As shown, the integrated simulation management platform of this invention integrates sub-VIs for model selection, data monitoring, basic control law parameter setting, control input setting, offline panel setting, in-loop simulation setting, in-loop control panel / instrumentation, and data storage, enabling helicopter configuration selection, initial trim speed selection, and flight data monitoring. The integrated simulation management platform transmits helicopter motion and state parameters to the visual system, flight quality evaluation system, and six-degree-of-freedom motion platform via UDP protocol.

[0056] like Figure 4As shown, the virtual central control console 2, relying on LabVIEW software and combined with touch screen hardware, simulates the control buttons, knobs, switches and instrument displays in the cockpit. When the pilot is conducting human-in-the-loop flight simulation, he can turn the control mode and the auxiliary driving function on and off through the knobs and buttons.

[0057] The flight simulation system described in this invention includes mathematical models of helicopters with various configurations. Each configuration corresponds to a helicopter flight mechanics model and a helicopter flight control system simulation model, capable of accurately simulating the six degrees of freedom motion characteristics of a helicopter and generating the motion and state parameters of the target helicopter. For example... Figure 5 For a single-rotor helicopter with a tail rotor, the flight dynamics model is as follows: Figure 6 This is a model for an explicit tracking control system.

[0058] The flight quality assessment system, combining offline simulation data such as AB arrays and human-in-the-loop simulation data such as control response, is used for quantitative evaluation of flight quality parameters such as bandwidth and phase delay, stability, inter-axis coupling, speed, large attitude changes, and collective pitch control response in hovering and low-speed states, and forward flight states. Figure 7 This is a flowchart for evaluating bandwidth and phase delay during hovering.

[0059] The helicopter flight simulator provided by this invention uses the following data communication method:

[0060] The flight simulation system, visual simulation system, and six-degree-of-freedom motion platform achieve data transmission between hardware systems via USB / HDMI and data communication between software systems via UDP protocol. This allows the flight attitude, flight position, and flight speed status information to be fed back to the visual and motion platforms, and then to the pilot.

[0061] The flight simulation system, integrated simulation management platform, joystick system, and virtual central control console 2 synchronize and transmit data between themselves through LabVIEW local variables and multi-threading.

[0062] The flight simulation system stores flight simulation data and flight quality assessment data in a queue format for flight simulation status monitoring and subsequent helicopter flight quality assessment.

[0063] This helicopter flight simulator employs a unified modular data interface. The helicopter flight control system simulation model includes a joystick input module, a control panel input module, a helicopter flight status input module, a flight control stick output module, and a flight control panel output module. The helicopter flight mechanics model includes a flight control stick input module and a flight status output module. For different helicopter configurations, rapid switching of the simulation interface for the corresponding configuration can be achieved without extensive modifications to the backend data interface of the integrated simulation management platform.

[0064] The helicopter flight simulator provided by this invention can be used to switch between offline and human-in-the-loop simulation modes for helicopter flight simulation. Both offline and human-in-the-loop simulations include three common steps: model selection, basic control law parameter setting, and data storage.

[0065] Step 1: Model selection. Select the helicopter flight mechanics model and the helicopter flight control system simulation model dll file respectively. Combined with the MIT (Model Interface Toolkit) toolbox, the model can be recognized and called in the LabVIEW integrated simulation management platform.

[0066] Step 2: Set basic control law parameters. Read the flight control parameter file and input it as an array into the helicopter flight control system simulation model. Select manual mode to modify the control parameters. Click "Save File" to save the newly modified control parameters.

[0067] Step 3: Data storage. Set the write frequency and use the queue operation in the LabVIEW program panel to save the helicopter flight data to a new file.

[0068] There are certain differences between offline and human-in-the-loop simulations in flight simulation. Offline flight simulation requires pre-setting the operating mode, response types of each channel, assisted pilot functions, and control inputs before the simulation begins. Human-in-the-loop simulation, on the other hand, needs to consider the real-time nature of the simulation more. Therefore, for offline simulation:

[0069] Step 4: Offline panel settings. Pre-set the main flight control functions and working mode selection, automatic flight control function, and boundary protection function. If you need to switch, select "Switch" and set the switching time and the mode after switching.

[0070] Step 5: Offline input settings. Using piecewise functions, step, square wave, dipole, frequency sweep, and sine signals are generated for each channel. Single-channel or multi-channel signal combinations are possible. Taking the "dipole" input as an example, this input can be completed using a for loop in LabVIEW, with time intervals of 1ms. The specific formula is as follows:

[0071]

[0072] Where t0 is the start time, d1 is the rise time, d2 is the fall time, D is the dipole width, and t set The total offline simulation time is A, and the dipole amplitude is A. In the "Offline lever control input" interface, only the above parameters need to be set for dipole control.

[0073] For human-in-the-loop flight simulation:

[0074] Step 4: Control instrument input, that is, to complete similar functions to the offline panel through the virtual central control panel 2. Here, the control mode is switched in real time through knobs, buttons and switches, and the status of the Boolean light below the button indicates whether the control mode has been switched.

[0075] Step 5: Real-time manipulation input. By connecting the external foot pedal 3, collective pitch joystick 4, side joystick 5, and center joystick 6 to the LabVIEW program panel, the joystick displacement is converted into the lever stroke in the model.

[0076] Step 6: In-Loop Simulation Settings, set the IP address and UDP data write port for the visual computer and simulator slave device, and enable the simulation visual and six-degree-of-freedom motion platform during human-in-the-loop simulation.

[0077] Based on flight simulation, this invention provides an integrated flight quality parameter evaluation method for quantitative evaluation of helicopter flight quality parameters, comprising the following steps:

[0078] Step 1: Select the flight condition and evaluation parameters to be evaluated;

[0079] Step 2: Read data files such as AB matrix, transfer function, and txt file;

[0080] Step 3: Select the channel to be evaluated, i.e., display the eigenvalues, time-domain response curve, frequency-domain response curve, etc.

[0081] Step 4: Display the rating assessment results and automatically generate them in a table;

[0082] Step 5: Exit the evaluation and select other parameters for the next evaluation step.

[0083] The following specific data examples illustrate the integrated quality evaluation method for helicopter flight simulators with multiple configurations according to the present invention:

[0084] The visual display system 1 of this invention uses three 34-inch curved displays, with a field of view of 155° horizontally and 55° vertically, which can provide pilots with a continuous and complete external view, including 3D models of helicopters of different configurations, runways, and virtual scene models of maneuvering subjects. It can generate helicopter motion and external flight simulation scene images that match the motion and state parameters.

[0085] The virtual central control console 2 of this invention includes a 27-inch virtual instrument display. Relying on LabVIEW software and combined with touch screen hardware, it simulates the control buttons, knobs, switches and instrument displays in the cockpit. When the pilot is conducting human-in-the-loop flight simulation, he can turn the control mode and the auxiliary driving function on and off through the knobs and buttons.

[0086] The control stick system of this invention includes a foot pedal 3, a collective pitch control stick 4, a side control stick 5, and a center control stick 6. Both the side control stick 5 and the center control stick 6 can realize lateral and longitudinal periodic pitch control. The simulator uses the center control stick 6. The buttons of the collective pitch control stick 4, the side control stick 5, and the center control stick 6 are set with stick trim and stick release functions to assist the pilot in flying the helicopter.

[0087] The integrated simulation management platform of this invention comprises three parts: a flight simulation workstation, a simulation management display, and a data monitoring display. Equipped with an instructor's console, it integrates sub-VIs for model selection, data monitoring, basic control law parameter setting, control input setting, offline panel setting, in-loop simulation setting, in-loop control panel / instrumentation, and data storage via LabVIEW software. This enables helicopter configuration selection, initial trim speed selection, and flight data monitoring. The integrated simulation management platform transmits helicopter motion and status parameters to the visual system, flight quality evaluation system, and six-degree-of-freedom motion platform via UDP protocol.

[0088] The six-degree-of-freedom platform of this invention is equipped with a joystick system, three visual displays, a 27-inch touch screen and a pilot seat. It receives real-time motion data such as roll angle, pitch angle, yaw angle, lateral movement, longitudinal movement and elevation movement of the aircraft via UDP protocol. The extended amount of the six electric cylinders of the six-degree-of-freedom motion platform is deduced by the built-in washing algorithm. Then, the electric cylinders are controlled to perform telescopic motion through servo drivers, so as to realize the translation and rotation of the motion platform in six degrees of freedom in space.

[0089] The flight simulation system of this invention provides mathematical models of helicopters with various configurations. Each configuration corresponds to a helicopter flight mechanics model and a helicopter flight control system simulation model. The helicopter mathematical model is solved with a 5ms timing period to simulate the six-degree-of-freedom motion characteristics of the target helicopter and generate the motion and state parameters of the target helicopter.

[0090] The integrated flight quality assessment system of this invention combines offline simulation data such as AB arrays and human-in-the-loop simulation data such as control response. It can be used for quantitative assessment of flight quality parameters such as bandwidth and phase delay, stability, inter-axis coupling, speed, large attitude changes, and collective pitch control response in hovering and low-speed states, and forward flight states.

[0091] Example 1: Offline simulation of typical control inputs in helicopter hovering state

[0092] The main steps for offline simulation of typical control inputs in a helicopter hovering state are as follows:

[0093] Step a1: Power on the system, select "Offline Simulation" mode in the "Simulation Type" drop-down box, set the "Balance Speed" and "Offline Simulation Time", and run the integrated management and control interface;

[0094] Step a2: Click the "Model Selection" button, select the helicopter flight dynamics and flight control model, click the "Basic Control Law Parameter Settings" button, and read or manually modify the control law parameters from a txt file;

[0095] Step a3: Click the "Data Storage" button to set the data write frequency and save path;

[0096] Step a4: Click the "Offline Panel Settings" button to pre-set the main flight control functions and working mode selection, automatic flight control function, and boundary protection function;

[0097] Step a5: Click the "Control Input Settings" button, select the control input channel, and set the typical step, square wave, dipole, and sine wave control inputs;

[0098] Step a6: Click the "Start" button to monitor the helicopter's flight status response and flight control response through the integrated simulation management platform;

[0099] Step a7: Click the "Stop" button to end the simulation;

[0100] Example 2: Flight Simulation of Helicopter "Obstacle Skiing" Maneuver

[0101] Step b1: Power on the system and start the simulation visuals and simulator control cabinet for the "obstacle skiing" subject;

[0102] Step b2: Select "In-Loop Simulation" mode in the "Simulation Type" drop-down box, run the integrated management and control interface, and the virtual central control console 2 will pop up automatically. Set the main flight control function, working mode, automatic flight control function, etc.

[0103] Step b3: Click the “Model Selection” button, select the helicopter flight dynamics and flight control model, click the “Basic Control Law Parameter Settings” button, and read or manually modify the control law parameters from the txt file;

[0104] Step b4: Click the "Data Storage" button to set the data write frequency and save path;

[0105] Step b5: Click the "In-Loop Simulation Settings" button to set the joystick sequence, view, simulator IP, and data write port;

[0106] Step b6: Click the "Start" button. Using the virtual central control console to view parameters such as the horizon, airspeed, and altitude, as well as obstacle indicators in the subject's visual field, the pilot manipulates the control stick to complete the flight simulation of the maneuver subject.

[0107] Step b7: Click the "Stop" button to end the simulation;

[0108] Example 3: Evaluation of bandwidth and phase delay during hovering

[0109] The main steps for evaluating bandwidth and phase delay during helicopter hovering are as follows:

[0110] Step c1: Power on the system and run the flight quality assessment interface;

[0111] Step c2: Select the "Hover and Low-Speed ​​Flight" state, click the "Bandwidth and Phase Delay" button, and the corresponding evaluation interface will pop up;

[0112] Step c3: Import the AB array file, import and read the basic control law parameter file, and set the basic control law parameters, time delay, and servo parameters;

[0113] Step c4: Select the states that need to be evaluated and view the frequency domain response curve and level graph;

[0114] Step c5: If you need to modify the control law parameters, click the "Basic Control Law Parameter Settings" button, select manual mode to modify the basic control law parameters or feedback parameters, and repeat step c4.

[0115] Step c6: Save the grading chart. If you need to proceed to the next set of data for evaluation, repeat steps c1 to c5; otherwise, exit the evaluation.

[0116] The specific evaluation steps are as follows: Figure 7 As shown:

[0117] Step 1: Select the flight state and evaluation parameters to be evaluated; Step 2: Read data files such as AB array, transfer function, and txt; Step 3: Select the channel to be evaluated, i.e., display eigenvalues, time-domain response curves, frequency-domain response curves, etc.; Step 4: Display the level evaluation results and automatically generate them in a table; Step 5: Exit the evaluation and select other parameters for the next evaluation step.

[0118] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements can be made without departing from the principle of the present invention, and these improvements should also be considered within the scope of protection of the present invention.

Claims

1. A helicopter flight simulator for multiple configurations, characterized in that, The hardware and software systems enable offline and human-in-the-loop flight simulation and integrated flight quality assessment for various helicopter configurations. The helicopter flight simulator includes hardware and software systems. The software system includes a flight simulation system, an integrated simulation management platform, a visual display system (1), a virtual central control console (2), and a flight quality assessment system; The flight simulation system includes mathematical models of helicopters with various configurations. Each configuration corresponds to a helicopter flight mechanics model and a helicopter flight control system simulation model, which can accurately simulate the six-degree-of-freedom motion characteristics of a helicopter and generate the motion and state parameters of the target helicopter. The integrated simulation management platform, through LabVIEW software, integrates sub-VIs for model selection, data monitoring, basic control law parameter setting, control input setting, offline panel setting, in-loop simulation setting, in-loop control panel / instrument, and data storage. It can realize helicopter configuration selection, initial trim speed selection, and flight data monitoring functions. The integrated simulation management platform transmits helicopter motion and status parameters to the visual system, flight quality evaluation system, and six-degree-of-freedom motion platform via UDP protocol. The visual display system (1) includes helicopter 3D models, runways, and virtual scene models of maneuver subjects with different configurations, and can generate helicopter motion and external flight simulation scene images that match the motion and state parameters. The virtual central control console (2) relies on LabVIEW software and touch screen hardware to simulate the control buttons, knobs, switches and instrument displays in the cockpit. When the pilot is conducting human-in-the-loop flight simulation, he can turn the control mode and the auxiliary driving function on and off through the knobs and buttons. The flight quality assessment system described above, combined with offline simulation data such as AB arrays and human-in-the-loop simulation data such as control response, can be used for quantitative assessment of flight quality parameters such as bandwidth and phase delay, stability, inter-axis coupling, speed, large attitude changes, and collective pitch control response in hovering and low-speed states, and forward flight states. The six-degree-of-freedom motion platform can be equipped with a visual display system (1), a virtual central control console (2), foot pedals (3), a collective pitch control stick (4), a side control stick (5), a central control stick (6), an integrated simulation management platform, and an acoustic simulation system. The lower computer of the six-degree-of-freedom motion platform receives the three-axis attitude angle, angular velocity, angular acceleration, fuselage position, three-axis body speed, ground speed, acceleration, fuselage angle of attack, sideslip angle, climb angle, and overload parameters generated by the integrated simulation management platform, and feeds them back to the motion platform and the driver through the extension and retraction of the electric cylinder (7). The hardware system includes two computers, five displays, a joystick system, a six-degree-of-freedom motion platform, and a control cabinet. The two computers are a visual computer and a simulation management computer. The visual computer is connected to three 34-inch curved displays, providing a field of view of 155° horizontally and 55° vertically, offering the pilot a continuous and complete external view. The simulation management computer is connected to a 27-inch display and a 27-inch touchscreen. The 27-inch display houses the integrated simulation management platform, and the 27-inch touchscreen houses the virtual central control console. The control stick system includes foot pedals (3), collective pitch control stick (4), side control stick (5) and center control stick (6). Both the side control stick (5) and the center control stick (6) can realize lateral and longitudinal periodic pitch control. The helicopter flight simulator uses the center control stick (6). The stick trim and stick release functions can be set by the upper buttons of the collective pitch control stick (4), side control stick (5) and center control stick (6), which can assist the pilot in flying the helicopter. The six-degree-of-freedom motion platform is equipped with a joystick system, three visual displays, a 27-inch touch screen, and a driver's seat. The control cabinet controls the telescopic movement of six electric cylinders to achieve the pitch, roll, yaw, longitudinal, lateral, and vertical movements of the entire motion platform. The integrated simulation management platform includes a simulation management module (21), a flight control monitoring module (22), and a data monitoring module (23).

2. The helicopter flight simulator for multiple configurations according to claim 1, characterized in that, The helicopter flight simulator described above uses the following data communication method: The flight simulation system, visual simulation system, and six-degree-of-freedom motion platform achieve data transmission between hardware systems via USB / HDMI and data communication between software systems via UDP protocol. This allows the flight attitude, flight position, and flight speed status information to be fed back to the visual and motion platforms, and then to the pilot. The flight simulation system, integrated simulation management platform, joystick system, and virtual central control console (2) synchronize and transmit data between them through LabVIEW local variables and multi-threading. The flight simulation system stores flight simulation data and flight quality assessment data in a queue format for flight simulation status monitoring and subsequent helicopter flight quality assessment. The helicopter flight simulator adopts a unified modular data interface. The helicopter flight control system simulation model includes a joystick input module, a control panel input module, a helicopter flight status input module, a flight control stick output module, and a flight control panel output module. The helicopter flight mechanics model includes a flight control stick input module and a flight status output module. For different helicopter configurations, the simulation interface of the corresponding configuration can be quickly switched without extensive modification of the background data interface of the integrated simulation management platform.

3. The integrated quality evaluation method for helicopter flight simulators with multiple configurations according to any one of claims 1 to 2, characterized in that, The helicopter flight simulator described above can be used in both offline and human-in-the-loop flight simulation modes. Both offline and human-in-the-loop simulations include three common steps: model selection, basic control law parameter setting, and data storage. Model selection: Select the helicopter flight mechanics model and the helicopter flight control system simulation model dll files respectively, and use the MIT toolbox to realize the recognition and calling of the models in the LabVIEW integrated simulation management platform; Basic control law parameter settings: Read the flight control parameter file and input it as an array into the helicopter flight control system simulation model. Select manual mode to modify the control parameters, and click save file to save the newly modified control parameters. Data storage: Set the write frequency and use the queue operation in the LabVIEW program panel to save the helicopter flight data to a new file; There are some differences between offline and human-in-the-loop simulations in flight simulation. Offline flight simulation requires pre-setting the working mode, response type of each channel, assisted driving functions, and control inputs before the simulation. Human-in-the-loop simulation, on the other hand, needs to consider the real-time performance of the simulation more.

4. The integrated quality evaluation method for helicopter flight simulators with multiple configurations according to claim 3, characterized in that, For offline simulation, the flight simulation steps are as follows: Offline panel settings: Pre-set the main flight control functions and working mode selection, automatic flight control function and boundary protection function. If you need to switch, select "Switch" and set the switching time and the mode after switching. Offline control input settings: By using piecewise functions, step, square wave, dipole, frequency sweep and sine signals are generated for each channel, and single-channel or multi-channel signals can be combined. For human-in-the-loop flight simulation, the flight simulation steps are as follows: The control instrument input, that is, the virtual central control panel (2) completes the same functions as the offline panel. Here, the control mode is switched in real time by knobs, buttons and switches, and the status of the Boolean light below the button shows whether the control mode has been switched. Real-time manipulation input is achieved by connecting external foot pedals (3), collective pitch joysticks (4), side joysticks (5), and center joysticks (6) to the LabVIEW program panel, converting joystick displacement into the amount of stroke in the model; In-Loop Simulation Settings: Configure the IP addresses and UDP data write ports for the visual computer and simulator slave device, and enable the simulation visuals and six-degree-of-freedom motion platform during human-in-the-loop simulation.

5. The integrated quality evaluation method for helicopter flight simulators with multiple configurations according to claim 4, characterized in that, After completing the flight simulation using a helicopter flight simulator, it can be directly used for integrated flight quality parameter evaluation. The method for quantitative parameter evaluation of helicopter flight quality is as follows: Step 1: Select the flight condition and evaluation parameters to be evaluated; Step 2: Read the AB matrix, transfer function, txt, and mat data files; Step 3: Select the channel to be evaluated, i.e., display the eigenvalues, time-domain response curve, and frequency-domain response curve; Step 4: Display the rating assessment results and automatically generate them in a table; Step 5: Exit the evaluation and select other parameters for the next evaluation step.

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