Aircraft gravity center real-time balancing method and system based on dynamic parameter fusion

Abstract

The invention belongs to the technical field of aircraft control, relates to an aircraft gravity center real-time balancing method and system based on dynamic parameter fusion, and aims to solve the problems of insufficient real-time performance, accuracy and self-adaptability of a gravity center balancing method under complex flight conditions in the prior art. The method comprises the steps that real-time parameters are obtained, and the real-time gravity center position is calculated; if the real-time gravity center position is not within the preset range, calculating a first inertia moment and a first additional moment caused by fuel density change and a second inertia moment and a second additional moment caused by aeroelastic deformation; performing inertia moment correction based on the first inertia moment and the second inertia moment; additional moment correction is carried out based on the first additional moment, the second additional moment and the real-time pitching inertia moment; when the real-time gravity center position is within the preset range, gravity center balancing is completed. The fuel oil density and aeroelastic parameters are estimated in real time through a self-adaptive control algorithm, rudder deflection and fuel oil distribution are cooperatively adjusted, and the problem of center-of-gravity shift under complex disturbance can be effectively solved.

Description

Background Art

[0002] In the field of modern aerospace engineering, aircraft center-of-gravity (CG) trimming, as a core technology of the flight control system, is directly related to flight stability, handling response performance, and fuel economy. A reasonable CG trimming method can effectively reduce flight resistance, reduce structural fatigue loads, and improve the control accuracy of avionics systems. However, the current mainstream CG trimming technologies are limited by traditional theoretical frameworks and algorithm models, and there are significant bottlenecks in aspects such as adaptability to dynamic working conditions and data processing accuracy, making it difficult to meet the application requirements of the rapid development of aerospace technology. Currently, aircraft CG trimming technologies mainly rely on static parameters or simplified dynamic models to achieve CG adjustment through fixed algorithms or offline calculations. They have the following technical characteristics: First, they adopt static trimming strategies and rely on initial data such as predefined fuel distributions and structural parameters for trimming calculations; second, they process single-source data and mostly rely on single-source data such as accelerometers and fuel quantity sensors; third, the mechanical models are highly simplified, and a trimming moment calculation model is constructed based on the assumption of a rigid wing. These technical deficiencies directly lead to three major problems: First, there is a lack of real-time performance. The static model cannot dynamically respond to changes in fuel distribution and aeroelastic deformations, resulting in trimming adjustments lagging behind actual CG offsets, seriously affecting flight stability; second, the accuracy is limited. The instability of single-source data and the problem of time asynchronization of multiple sensors lead to an increase in data fusion errors, weak measurement noise suppression ability, and insufficient data integrity, making it difficult to achieve precise trimming; third, the model simplification error is significant. Due to the lack of consideration of aeroelastic effects (such as changes in additional aerodynamic moments and moments of inertia caused by wing bending and torsion deformations), the calculation deviation of the moment of inertia is further amplified, resulting in the trimming result deviating from the actual requirements, increasing flight safety hazards and reducing fuel economy. With the development of aerospace technology towards high speed and intelligence, the flight conditions faced by aircraft are becoming increasingly complex, posing higher requirements for the CG trimming ability. Therefore, there is an urgent need to develop a new type of aircraft CG trimming technology that can overcome the above deficiencies to meet the strict requirements for flight performance and safety in the modern aerospace field. Summary of the Invention

[0003] To solve the above problems in the prior art, that is, the lack of real-time performance, accuracy, and self-adaptability of the aircraft CG trimming method under complex flight conditions, the first aspect of the present invention proposes an aircraft real-time CG trimming method based on dynamic parameter fusion, which includes the following steps: S1. Obtain sensor data and perform preprocessing to obtain real-time parameters, where the real-time parameters include flight state and environmental parameters, fuel state parameters, wing deformation parameters, and mechanical property parameters; S2. Obtain the real-time CG position based on the real-time parameters; S3. If the real-time center of gravity position is not within the preset target range, based on the real-time parameters, determine the first moment of inertia and the first additional moment caused by the change in fuel density, and the second moment of inertia and the second additional moment caused by aeroelastic deformation; S4. Obtain the real-time pitch moment of inertia based on the first moment of inertia and the second moment of inertia, and perform moment of inertia correction; S5. Calculate the fuel transfer rate based on the first additional moment and the real-time center of gravity position, and determine the fuel redistribution command; S6. Calculate the rudder deflection angle based on the first additional moment, the second additional moment, and the real-time pitch moment of inertia, and determine the rudder deflection command; S7. Execute the fuel redistribution command and / or the rudder deflection command to perform additional moment correction; S8. After the additional moment correction is completed, when the real-time center of gravity position is within the preset target range, complete the center of gravity trimming.

[0004] In some preferred embodiments, the preprocessing is performed as follows: Adopt a sliding window filtering algorithm to eliminate sensor noise, dynamically remove outliers in the sensor data that exceed the preset threshold range, and perform data cleaning; Predict the flight state parameters based on the LSTM neural network, and output the predicted value of the flight state at the next moment to compensate for the sensor transmission delay and achieve the time stamp synchronization of multi-source data; Analyze the fuel tank state to determine the fuel state parameters; the fuel state parameters include the horizontal distance of the fuel tank centroid relative to the Y-axis, the horizontal distance of the fuel tank centroid relative to the X-axis, the vertical distance of the fuel tank centroid relative to the Y-axis, and the change in the fuel mass of the fuel tank in the body coordinate system of the aircraft; Analyze the wing deformation to determine the wing deformation parameters and mechanical characteristic parameters; the wing deformation parameters include the vertical displacement of the wing and the real-time displacement of the wing tip, and the mechanical characteristic parameters include the wing bending stiffness, the mass distribution per unit length of the wing, and the aerodynamic load distribution function.

[0005] In some preferred embodiments, the method for obtaining the real-time center of gravity position based on the real-time parameters is as follows: Input the real-time parameters into the pre-constructed fuel dynamic model and aeroelastic model respectively, and calculate the fuel center of gravity offset and the aeroelastic center of gravity offset through the models; Based on the aeroelastic center of gravity offset and the fuel center of gravity offset, combined with the design reference center of gravity position, calculate the real-time center of gravity position ; ; Wherein, is the fuel center of gravity offset, is the aerodynamic elastic center of gravity offset, is the design reference center of gravity position.

[0006] In some preferred embodiments, the fuel transfer rate is calculated as follows: Based on the first additional moment and the real-time center of gravity position, determine the i fuel density change of the th fuel tank ; Based on the fuel density change, calculate the fuel transfer rate : ; wherein, is the real-time volume of the fuel tank, is the first additional moment, is the i horizontal distance of the centroid of the th fuel tank relative to the X-axis; is the fuel pump time constant,

[0007] is the real-time center of gravity position. ; wherein, is the real-time pitch moment of inertia; is the original moment of inertia of the rigid wing, is the first moment of inertia, is the second moment of inertia.

[0008] In some preferred embodiments, the control surface deflection angle is calculated based on the first additional moment, the second additional moment and the real-time pitch moment of inertia, and the method is as follows: Define the control input to cancel the first additional moment with the aerodynamic moment and the second additional moment , and determine the aerodynamic moment as: ; Based on the control input, convert the aerodynamic moment into the control surface deflection angle and calculate the deflection angle : ; wherein, is the second-order time derivative of the desired pitch angle; is the proportional gain matrix; is the differential gain matrix; is the pitch angle tracking error, is the first-order time derivative of the pitch angle tracking error; is the elevator moment coefficient; is the air density; is the airspeed; is the wing reference area; is the mean aerodynamic chord.

[0009] In some preferred embodiments, a fuel redistribution instruction and a rudder deflection instruction are executed to perform additional moment correction. The method is as follows: Determine the fuel redistribution instruction according to the fuel transfer rate, control the transfer speed of fuel between different fuel tanks, and change the mass distribution; Determine the rudder deflection instruction according to the deflection angle, and synchronously deflect the rudder surface to compensate for the instantaneous moment change during the fuel transfer process.

[0010] A second aspect of the present invention proposes an aircraft center-of-gravity real-time trimming system based on dynamic parameter fusion. The system includes: A data acquisition module configured to acquire sensor data and perform preprocessing to obtain real-time parameters, where the real-time parameters include flight state and environmental parameters, fuel state parameters, wing deformation parameters, and mechanical property parameters; A center-of-gravity calculation module configured to obtain the real-time center-of-gravity position based on the real-time parameters; A deviation judgment module configured to compare the real-time center-of-gravity position with a preset target range and output a judgment result; A center-of-gravity trimming module configured to perform fuel redistribution and / or rudder deflection in response to an indication that the judgment result does not meet the standard, so as to correct the moment of inertia and additional moment and perform center-of-gravity trimming; A control module configured to, after the center-of-gravity trimming module completes the adjustment, control the center-of-gravity calculation module to recalculate the real-time center-of-gravity position, and repeatedly execute the operations of the deviation judgment unit and the center-of-gravity trimming module until the real-time center-of-gravity position falls within the preset target range; To perform center-of-gravity trimming, the method is as follows: Based on the real-time parameters, determine the first moment of inertia and the first additional moment caused by the change in fuel density, and the second moment of inertia and the second additional moment caused by aeroelastic deformation; Obtain the real-time pitch moment of inertia based on the first moment of inertia and the second moment of inertia, and perform moment-of-inertia correction; Based on the first additional moment and the real-time center-of-gravity position, obtain the fuel density change amount, and then calculate the fuel transfer rate to determine the fuel redistribution instruction; Based on the first additional moment, the second additional moment, and the real-time pitch moment of inertia, obtain the aerodynamic moment, convert the aerodynamic moment into the rudder surface deflection angle, and determine the rudder deflection instruction; Execute the fuel redistribution instruction and / or the rudder deflection instruction to perform additional moment correction.

[0011] Advantages of the present invention: Through dynamic parameter fusion and real-time closed-loop control, the present invention estimates the fuel density and aeroelastic parameters in real time through an adaptive control algorithm, and collaboratively adjusts the elevator deflection and fuel distribution, effectively coping with the problem of center-of-gravity shift under complex disturbances, improving the trimming accuracy and response speed, and solving the limitations of traditional methods in aspects such as fuel-aeroelastic coupling, multi-source data asynchrony, and parameter time-variation, providing an intelligent trimming solution with high precision and high real-time performance for highly maneuverable aircraft. Description of the Drawings

[0012] By reading the detailed description of the non-limiting embodiments with reference to the following drawings, other features, objectives, and advantages of the present application will become more apparent: Figure 1 It is a flowchart of a method for real-time trimming of an aircraft center of gravity based on dynamic parameter fusion in an embodiment of the present invention. Detailed Embodiments

[0013] The following further elaborates the present application in conjunction with the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the related invention and are not intended to limit the invention. Additionally, it should be noted that for the convenience of description, only parts related to the relevant invention are shown in the drawings.

[0014] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the drawings and embodiments.

[0015] The present invention provides a method for real-time trimming of an aircraft center of gravity based on dynamic parameter fusion. This method simultaneously considers the center-of-gravity shift caused by the dynamic distribution of fuel and aeroelastic deformation, and realizes the real-time trimming of the aircraft center of gravity through dynamic parameter fusion and real-time closed-loop control.

[0016] A method for real-time trimming of an aircraft center of gravity based on dynamic parameter fusion of the present invention includes the following steps: S1. Obtain sensor data and perform preprocessing to obtain real-time parameters, where the real-time parameters include flight state and environmental parameters, fuel state parameters, wing deformation parameters, and mechanical property parameters; S2. Obtain the real-time center-of-gravity position based on the real-time parameters; S3. If the real-time center-of-gravity position is not within the preset target range, based on the real-time parameters, determine the first moment of inertia, the first additional moment caused by the change in fuel density, and the second moment of inertia, the second additional moment caused by aeroelastic deformation; S4. Obtain the real-time pitch moment of inertia based on the first moment of inertia and the second moment of inertia, and perform moment of inertia correction; S5. Obtain the fuel density change based on the first additional moment and the real-time center of gravity position, and then calculate the fuel transfer rate to determine the fuel reallocation instruction; S6. Obtain the aerodynamic moment based on the first additional moment, the second additional moment and the real-time pitch moment of inertia, convert the aerodynamic moment into the rudder deflection angle, and determine the rudder deflection instruction; S7. Execute the fuel reallocation instruction and / or the rudder deflection instruction to perform additional moment correction; S8. After the additional moment correction is completed, when the real-time center of gravity position is within the preset target range, the center of gravity trimming is completed.

[0017] For a clearer description of the aircraft center of gravity real-time trimming method based on dynamic parameter fusion of the present invention, the following will be combined with Figure 1 Each step in the embodiments of the present invention will be described in detail.

[0018] The aircraft center of gravity real-time trimming method based on dynamic parameter fusion in the first embodiment of the present invention includes steps S1 - S8, and each step is described in detail as follows: S1. Obtain sensor data and perform preprocessing to obtain real-time parameters, where the real-time parameters include flight state and environmental parameters, fuel state parameters, wing deformation parameters and mechanical property parameters.

[0019] Preferably, in this embodiment, the sensors include: Flight attitude and environment perception sensors, which are used to monitor the aircraft state, obtain the position, speed and attitude information of the aircraft, and external environmental condition data; Fuel system state monitoring sensors, which are used to monitor the state of the fuel system in real time, and obtain the fuel quantity, fuel temperature and fuel pressure of each fuel tank; Wing structure monitoring sensors, which are used to monitor the stress and deformation of the wing structure, and measure the stress and deformation of the wing under different flight conditions in real time.

[0020] Preferably, in this embodiment, the preprocessed data is used as the input of the comprehensive mechanical model, and the real-time parameters are updated in real time in combination with the adaptive parameter estimation method.

[0021] Further preferably, the method for preprocessing the obtained multi-source sensor data is as follows: S11. Use the sliding window filtering algorithm to eliminate sensor noise (such as outliers in simulator data), dynamically eliminate the outliers in the sensor data that exceed the preset threshold range, and perform data cleaning: ; Wherein, is the filtered output value at time k ; is the historical N sampling values (in this embodiment N= is 50); is the length or time interval of the time window of the window, that is, the duration covered by the window on the time axis, and is used to define the time range for processing data each time; S12. Predict the flight state parameters based on the LSTM neural network and output the predicted value of the flight state at the next moment , to compensate for the sensor transmission delay and achieve the timestamp synchronization of multi-source data: ; Among them, is the hidden layer state, and are weight matrices, is the activation function is the input feature vector, b is the bias vector.

[0022] S13. Analyze the fuel tank state to determine the fuel state parameters; the fuel state parameters include the horizontal distance of the fuel tank centroid relative to the Y-axis, the horizontal distance of the fuel tank centroid relative to the X-axis, the vertical distance of the fuel tank centroid relative to the Y-axis, and the fuel mass change of the fuel tank in the body coordinate system of the aircraft; in the body coordinate system of the aircraft, the axis passing through both wings and through the center of gravity is called the Y-axis, also called the transverse axis.

[0023] S14. Analyze the wing deformation according to the Timoshenko beam theory to determine the wing deformation parameters and mechanical characteristic parameters; the wing deformation parameters include the vertical displacement of the wing and the real-time displacement of the wing tip, and the mechanical characteristic parameters include the wing bending stiffness, the mass distribution per unit length of the wing, and the aerodynamic load distribution function.

[0024] S2. Obtain the real-time center of gravity position based on the real-time parameters, and the method is: Input the real-time parameters into the pre-constructed fuel dynamic model and aeroelastic model respectively, and calculate the fuel center of gravity offset and aeroelastic center of gravity offset through the models; Based on the aeroelastic center of gravity offset and the fuel center of gravity offset, combined with the design reference center of gravity position, calculate the real-time center of gravity position.

[0025] Preferably, the construction method of the fuel dynamic model is: Simulate fuel sloshing according to the SPH algorithm and calculate the fuel center of gravity offset: ; Among them, is the i mass of the nth fuel particle, is the particle deformation function; Preferably, the aeroelastic model is constructed as follows: According to the wing deformation parameters and mechanical characteristic parameters, the wing deformation is: ; In the formula, is the flexural rigidity of the wing, is the vertical displacement of the wing ( m ); is the aerodynamic load distribution function ( ), is the mass per unit length ( ); According to the change of the vertical displacement of the wing and the mass distribution per unit length of the wing, combined with the current total mass of the aircraft, calculate the center of gravity shift caused by aeroelasticity to obtain the aeroelastic center of gravity shift amount: ; Among them, is the current total mass of the aircraft (kg), is the mass distribution per unit length of the wing ( ); L is the wingspan length of the wing ( m ).

[0026] Preferably, based on the aeroelastic center of gravity shift amount and the fuel center of gravity shift amount, combined with the design reference center of gravity position, calculate the real-time center of gravity position.

[0027] ; Among them, is the design reference center of gravity position ( m ).

[0028] S3. Judge whether the real-time center of gravity position is within the preset target range. If so, end the process and complete the center of gravity trimming; otherwise, execute step S4.

[0029] S4. Determine the first moment of inertia, the first additional moment caused by the change of fuel density, and the second moment of inertia, the second additional moment caused by aeroelastic deformation.

[0030] Preferably, the method for obtaining the first moment of inertia and the first additional moment caused by the change of fuel density is: According to the horizontal distance of the fuel tank centroid relative to the Y-axis, the vertical distance of the fuel tank centroid relative to the Y-axis, and the change amount of the fuel mass in the fuel tank in the real-time parameters, calculate and determine the first moment of inertia caused by the change of the fuel density in the fuel tank: ; Calculate the first additional moment caused by the change in fuel density of the fuel tank based on the horizontal distance of the centroid of the fuel tank relative to the X-axis in the real-time parameters and in combination with the real-time centroid position: ; Wherein, is the change in fuel mass of the i th fuel tank; x i is the horizontal distance of the centroid of the i th fuel tank relative to the Y-axis; z i is the vertical distance of the centroid of the i th fuel tank relative to the Y-axis; is the horizontal distance of the centroid of the i th fuel tank relative to the X-axis ( m ), g is the acceleration due to gravity.

[0031] Preferably, obtain the second moment of inertia and the second additional moment caused by aeroelastic deformation, and the method is as follows: Calculate the second moment of inertia caused by the deformation of the wing according to the mass distribution per unit length of the wing and the change in the vertical displacement of the wing : ; Wherein, is the mass distribution per unit length of the wing; L is the wingspan length of the wing; is the vertical displacement of the wing; Calculate the second additional moment caused by the deformation of the wing according to the change in the real-time displacement of the wing tip and in combination with the aeroelastic coupling coefficient: ; Wherein, is the aeroelastic coupling coefficient; is the real-time displacement of the wing tip.

[0032] S5. Obtain the real-time pitch moment of inertia based on the first moment of inertia and the second moment of inertia, and perform moment of inertia correction; ; Wherein, is the real-time pitch moment of inertia ( ); is the original moment of inertia of the rigid wing ( ).

[0033] S6. Obtain the fuel density change amount based on the first additional moment and the real-time centroid position, and then calculate the fuel transfer rate and determine the fuel redistribution instruction, and the method is as follows: Based on the first additional moment and the real-time center of gravity position, determine the i change in fuel density of the th fuel tank ; Based on the change in fuel density, calculate the fuel transfer rate : ; where is the real-time volume of the fuel tank, is the first additional moment, is the i horizontal distance of the centroid of the th fuel tank relative to the X-axis; is the fuel pump time constant,

[0034] S7. Obtain the aerodynamic moment based on the first additional moment, the second additional moment and the real-time pitch inertia moment, convert the aerodynamic moment into a rudder deflection angle, and determine the rudder deflection command. The method is as follows: Define the control input: ; where, with the aerodynamic moment canceling the first additional moment and the second additional moment , is the second-order time derivative of the desired pitch angle; is the proportional gain matrix; is the differential gain matrix; is the pitch angle tracking error, is the first-order time derivative of the pitch angle tracking error; Based on the control input, convert the aerodynamic moment into a rudder deflection angle and calculate the deflection angle : ; where is the elevator moment coefficient; is the air density; is the airspeed; is the wing reference area; is the mean aerodynamic chord length.

[0035] S8. Execute the fuel redistribution command and the rudder deflection command to perform additional moment correction. The method is as follows: Determine the fuel redistribution command according to the fuel transfer rate, control the transfer speed of fuel between different fuel tanks, and change the mass distribution; Determine the rudder deflection command according to the deflection angle, and synchronously deflect the control surface to compensate for the instantaneous moment change during the fuel transfer process.

[0036] Preferably, in this embodiment, according to the actual control requirements, it is possible to choose to perform center of gravity trimming through fuel redistribution, or to perform center trimming and cooperate with rudder deflection control through fuel redistribution for center of gravity trimming.

[0037] Preferably, in this embodiment, in case of an emergency, the control surface trimming is preferentially used to stabilize the attitude; when the center of gravity position slowly shifts due to fuel consumption, the fuel transfer is gradually started, the fuel system transfers fuel at a set rate, and the control surface deflects synchronously to compensate for the instantaneous moment change during the fuel transfer process.

[0038] Further preferably, control the fuel transfer speed according to the calculated fuel transfer rate, change the mass distribution, so as to achieve compensation of the center of gravity; control the control surface deflection according to the obtained deflection angle to compensate for the instantaneous moment change during the fuel transfer process.

[0039] Fuel is usually stored in the wing tanks and the central tank, and some aircraft models (such as large airliners or transport aircraft) may be equipped with front / rear auxiliary tanks. The fuel is transferred between different tanks by fuel pumps to change the mass distribution of the aircraft. For example, when moving the center of gravity forward, pump the fuel from the rear tank to the front tank; when moving the center of gravity backward, transfer the fuel from the front tank or the central tank to the rear tank. The flight management computer monitors the center of gravity position in real time and automatically adjusts the fuel transfer according to the flight phase (such as cruise, descent). During long-distance cruise, as the fuel is consumed, the center of gravity may move backward, and the system automatically transfers the rear fuel forward to maintain the optimal center of gravity range; when preparing for landing, ensure that the fuel distribution makes the center of gravity within a safe range to avoid difficulty in pitch control during landing.

[0040] Adjust the pitch angle by deflecting the control surface, and use the aerodynamic moment to offset the pitch moment generated by the center of gravity shift to achieve trimming of the center of gravity position. Although the control surface adjustment cannot directly change the center of gravity position, it can quickly respond to the change of flight attitude and can cope with sudden center of gravity shift, which is a key operation for flight safety.

[0041] Preferably, in this embodiment, taking the center of gravity moving backward during long-distance cruise as an example, the following steps are specifically for trimming the center of gravity by combining the two methods: 1) Conduct problem analysis: The fuel consumption causes the fuel in the wing tanks to decrease, the center of gravity gradually moves backward, and the aircraft shows a nose-up trend. It is necessary to continuously deflect the elevator downward to maintain the pitch angle, but this will increase the drag; 2) Perform center of gravity trimming according to the real-time center of gravity trimming method of the aircraft based on dynamic parameter fusion: Priority of the control surface: The automatic trimming system deflects the elevator downward, immediately generating a nose-down moment to offset the nose-up trend; Fuel adjustment: Calculate the fuel transfer rate in real time, start the fuel pump to transfer the fuel from the rear fuel tank forward, and gradually shift the center of gravity forward; Dynamic decoupling: Calculate the deflection angle in real time. As the center of gravity moves forward, gradually reduce the elevator deflection until the fuel adjustment is completed and the control surface returns to the neutral position.

[0042] After the additional moment correction is completed in S9, return to S1, re-obtain the real-time parameters, calculate the real-time center of gravity position, and repeat steps S1 to S8 until the real-time center of gravity position is within the target range, and the center of gravity trimming is completed.

[0043] In the above embodiments, although the steps are described in the above order, those skilled in the art can understand that in order to achieve the effects of this embodiment, different steps do not have to be executed in such an order. They can be executed simultaneously (in parallel) or in reverse order, and these simple changes are all within the protection scope of the present invention.

[0044] The aircraft center of gravity real-time trimming system based on dynamic parameter fusion according to the second embodiment of the present invention, the system includes: A data acquisition module configured to acquire sensor data and perform preprocessing to obtain real-time parameters, where the real-time parameters include flight state and environmental parameters, fuel state parameters, wing deformation parameters, and mechanical property parameters; A center of gravity calculation module configured to obtain the real-time center of gravity position based on the real-time parameters; A deviation judgment module: configured to compare the real-time center of gravity position with a preset target range and output a judgment result; A center of gravity trimming module configured to perform fuel reallocation and rudder deflection in response to the judgment result indicating non-compliance to correct the moment of inertia and additional moment and perform center of gravity trimming; A control module configured to, after the center of gravity trimming module completes the adjustment, control the center of gravity calculation module to recalculate the real-time center of gravity position and loop through the operations of the deviation judgment unit and the center of gravity trimming module until the real-time center of gravity position falls within the preset target range; To perform center of gravity trimming, the method is as follows: Based on the real-time parameters, determine the first moment of inertia and the first additional moment caused by the change in fuel density, and the second moment of inertia and the second additional moment caused by aeroelastic deformation; Obtain the real-time pitch moment of inertia based on the first moment of inertia and the second moment of inertia, and perform moment of inertia correction; Based on the first additional moment and the real-time center of gravity position, obtain the fuel density change amount, and then calculate the fuel transfer rate to determine the fuel reallocation instruction; Obtain the aerodynamic moment based on the first additional moment, the second additional moment and the real-time pitch moment of inertia, convert the aerodynamic moment into the rudder deflection angle, and determine the rudder deflection command. Execute the fuel reallocation command and the rudder deflection command to perform additional moment correction.

[0045] It should be noted that the aircraft center-of-gravity real-time trimming system based on dynamic parameter fusion provided in the above embodiment is only illustrated by dividing the above functional modules. In practical applications, the above functions can be allocated to different functional modules according to needs, that is, the modules or steps in the embodiments of the present invention can be further decomposed or combined. For example, the modules in the above embodiment can be combined into one module, or further split into multiple sub-modules to complete all or part of the functions described above. For the names of the modules and steps involved in the embodiments of the present invention, they are only used to distinguish each module or step, and are not regarded as an improper limitation of the present invention.

[0046] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes and related descriptions of the above-described system can refer to the corresponding processes in the foregoing method embodiments, and will not be elaborated herein.

[0047] An electronic device according to a third embodiment of the present invention includes: At least one processor; and A memory communicatively connected to at least one of the processors; wherein, The memory stores instructions executable by the processor, and the instructions are used to be executed by the processor to implement the above-mentioned aircraft center-of-gravity real-time trimming method based on dynamic parameter fusion.

[0048] A computer-readable storage medium according to a fourth embodiment of the present invention stores computer instructions, and the computer instructions are used to be executed by a computer to implement the above-mentioned aircraft center-of-gravity real-time trimming method based on dynamic parameter fusion.

[0049] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes and related descriptions of the above-described electronic device and computer-readable storage medium can refer to the corresponding processes in the foregoing method embodiments, and will not be elaborated herein.

[0050] Those skilled in the art should be able to realize that the modules and method steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of the two. The programs corresponding to the software modules and method steps can be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the technical field. To clearly illustrate the interchangeability of electronic hardware and software, the components and steps of each example have been generally described according to functions in the above description. Whether these functions are executed in the manner of electronic hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0051] Computer program code for performing the operations of the present application can be written in one or more programming languages or combinations thereof. The above programming languages include object-oriented programming languages - such as Java, Smalltalk, C++, and also include conventional procedural programming languages - such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, executed as an independent software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer can be connected to the user's computer through any kind of network - including a local area network (LAN) or a wide area network (WAN) - or, alternatively, can be connected to an external computer (for example, by using an Internet service provider to connect through the Internet).

[0052] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present application. In this regard, each block in the flowchart or block diagram can represent a module, a program segment, or a part of code that contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than marked in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, and they can sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and the combination of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system for performing the specified functions or operations, or can be implemented by a combination of dedicated hardware and computer instructions.

[0053] The terms "first", "second", etc. are used to distinguish similar objects and are not used to describe or indicate a specific order or sequence.

[0054] The term "comprising" or any other similar term is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus / device that comprises a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to those process, method, article, or apparatus / device.

[0055] So far, the technical solution of the present invention has been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easily understood by those skilled in the art that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A real-time aircraft center of gravity trimming method based on dynamic parameter fusion, characterized in that, The method includes the following steps: S1. Obtain sensor data and perform preprocessing to obtain real-time parameters, where the real-time parameters include flight state and environmental parameters, fuel state parameters, wing deformation parameters, and mechanical characteristic parameters; S2. Obtain the real-time center of gravity position based on the real-time parameters; S3. If the real-time center of gravity position is not within the preset target range, based on the real-time parameters, determine the first moment of inertia and the first additional moment caused by the change in fuel density, and the second moment of inertia and the second additional moment caused by aeroelastic deformation; S4. Obtain the real-time pitch moment of inertia based on the first moment of inertia and the second moment of inertia, and perform moment of inertia correction; S5. Calculate the fuel transfer rate based on the first additional moment and the real-time center of gravity position, and determine the fuel redistribution instruction; S6. Calculate the rudder deflection angle based on the first additional moment, the second additional moment, and the real-time pitch moment of inertia, and determine the rudder deflection instruction; S7. Execute the fuel redistribution instruction and / or the rudder deflection instruction to perform additional moment correction; S8. After the additional moment correction is completed, when the real-time center of gravity position is within the preset target range, complete the center of gravity trimming.

2. The aircraft based on dynamic parameter fusion according to claim 1 A real-time center of gravity trimming method, characterized in that the preprocessing method is as follows: Use a sliding window filtering algorithm to eliminate sensor noise, dynamically eliminate outliers in the sensor data that exceed the preset threshold range, and perform data cleaning; Predict flight state parameters based on an LSTM neural network, and output the predicted value of the flight state at the next moment to compensate for the sensor transmission delay and achieve multi-source data timestamp synchronization; Analyze the fuel tank state to determine the fuel state parameters; the fuel state parameters include, in the aircraft body coordinate system, the horizontal distance of the fuel tank centroid relative to the Y-axis, the horizontal distance of the fuel tank centroid relative to the X-axis, the vertical distance of the fuel tank centroid relative to the Y-axis, and the change in fuel mass of the fuel tank; Analyze the wing deformation to determine the wing deformation parameters and the mechanical characteristic parameters; the wing deformation parameters include the wing vertical displacement and the wing tip real-time displacement, and the mechanical characteristic parameters include the wing bending stiffness, the wing unit length mass distribution, and the aerodynamic load distribution function.

3. The real-time trim method for the center of gravity of an aircraft based on dynamic parameter fusion according to claim 2, characterized in that The method for obtaining the real-time center of gravity position based on the real-time parameters is as follows: Input the real-time parameters into a pre-constructed fuel dynamic model and aeroelastic model respectively, and calculate the fuel center of gravity offset and the aeroelastic center of gravity offset through the models; Based on the aeroelastic center of gravity offset and the fuel center of gravity offset, combined with the design reference center of gravity position, calculate the real-time center of gravity position ; ； wherein, is the fuel center of gravity offset, is the aeroelastic center of gravity offset, is the design reference center of gravity position.

4. The real-time trim method for the center of gravity of an aircraft based on dynamic parameter fusion according to claim 3, wherein The method for obtaining the first moment of inertia and the first additional moment caused by the change in fuel density is as follows: Determine the first moment of inertia caused by the change in fuel density in the fuel tank according to real-time parameters : ； wherein, is the fuel mass change of the i th fuel tank; is the horizontal distance of the centroid of the i th fuel tank relative to the Y-axis; is the vertical distance of the centroid of the i th fuel tank relative to the Y-axis; According to the real-time parameters, combined with the real-time center of gravity position, calculate the first additional moment caused by the change in fuel density in the fuel tank; ； Among them, is the horizontal distance of the centroid of the i th fuel tank relative to the X-axis; g is the acceleration due to gravity.

5. The aircraft based on dynamic parameter fusion according to claim 3 A real-time center of gravity trimming method, characterized in that The method for obtaining the second moment of inertia and the second additional moment caused by aeroelastic deformation is as follows: Determine the second moment of inertia caused by wing deformation according to real-time parameters : ； Among them, is the mass distribution per unit length of the wing; L is the wingspan length of the wing; is the vertical displacement of the wing; According to real-time parameters and combined with the aeroelastic coupling coefficient, calculate the second additional moment caused by the wing deformation : ； Among them, is the aeroelastic coupling coefficient; is the real-time displacement of the wing tip.

6. The real-time trimming method for the aircraft center of gravity based on dynamic parameter fusion according to claim 1, wherein The method for calculating the fuel transfer rate is as follows: Based on the first additional moment and the real-time center of gravity position, determine the i fuel density change of the th fuel tank ； Calculate the fuel transfer rate based on the change in fuel density : ； Among them, is the real-time volume of the fuel tank, is the first additional moment, is the i horizontal distance of the centroid of the nth fuel tank relative to the X-axis; is the time constant of the fuel pump, is the real-time center of gravity position.

7. The real-time trim method for the aircraft center of gravity based on dynamic parameter fusion according to claim 1, characterized in that The method for obtaining the real-time pitch moment of inertia is as follows: ； Among them, is the real-time pitch moment of inertia; is the original moment of inertia of the rigid wing, is the first moment of inertia, is the second moment of inertia.

8. The real-time aircraft center-of-gravity trimming method based on dynamic parameter fusion according to claim 7, characterized in that The method for calculating the rudder deflection angle is as follows: Define a control input to generate an aerodynamic moment to counteract the first additional moment and the second additional moment , and determine the aerodynamic moment as follows: ； Convert the aerodynamic moment to the rudder deflection angle based on the control input and calculate the deflection angle : ； wherein, is the second-order time derivative of the desired pitch angle; is the proportional gain matrix; is the derivative gain matrix; is the pitch angle tracking error, is the first-order time derivative of the pitch angle tracking error; is the elevator moment coefficient; is the air density; is the airspeed; is the wing reference area; is the mean aerodynamic chord length.

9. The real-time trimming method for the center of gravity of an aircraft based on dynamic parameter fusion according to claim 1, wherein The method for executing the fuel redistribution instruction and the rudder deflection instruction to perform additional moment correction is as follows: According to the fuel transfer rate, determine the fuel redistribution instruction, control the transfer speed of fuel between different fuel tanks, and change the mass distribution; Determine the rudder deflection command according to the deflection angle, and synchronously deflect the control surface to compensate for the instantaneous moment change during the fuel transfer process.

10. An aircraft center-of-gravity real-time trimming system based on dynamic parameter fusion, characterized in that, The system includes: A data acquisition module configured to acquire sensor data and perform preprocessing to obtain real-time parameters, where the real-time parameters include flight state and environmental parameters, fuel state parameters, wing deformation parameters, and mechanical property parameters; A center of gravity calculation module configured to obtain the real-time center of gravity position based on the real-time parameters; A deviation judgment module configured to compare the real-time center of gravity position with a preset target range and output a judgment result; A center of gravity trimming module configured to, in response to the judgment result indicating non-compliance, perform fuel reallocation and rudder deflection to correct the moment of inertia and additional moment for center of gravity trimming; A control module configured to, after the center of gravity trimming module completes the adjustment, control the center of gravity calculation module to recalculate the real-time center of gravity position and loop through the operations of the deviation judgment module and the center of gravity trimming module until the real-time center of gravity position falls within the preset target range; Perform center of gravity trimming, and the method is as follows: Based on the real-time parameters, determine the first moment of inertia and the first additional moment caused by the fuel density change, and the second moment of inertia and the second additional moment caused by the aeroelastic deformation; Obtain the real-time pitch moment of inertia based on the first moment of inertia and the second moment of inertia, and perform moment of inertia correction; Obtain the fuel density change amount based on the first additional moment and the real-time center of gravity position, and then calculate the fuel transfer rate to determine the fuel reallocation command; Obtain the aerodynamic moment based on the first additional moment, the second additional moment, and the real-time pitch moment of inertia, convert the aerodynamic moment into the control surface deflection angle, and determine the rudder deflection command; Execute the fuel reallocation command and / or the rudder deflection command to perform additional moment correction.

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