An aircraft motion simulation method based on digital twinning

Abstract

The present application relates to the field of aircraft simulation and digital twinning technology, and particularly relates to an aircraft motion simulation method based on digital twinning, comprising the following steps: S1: acquiring in real time the angle of attack, the sideslip angle, the fuel quantity and the environmental turbulence intensity of the aircraft; S2: matching the basic lift coefficient and the drag coefficient from the aerodynamic database, and simultaneously calculating the real-time mass and the moment of inertia of the aircraft; S3: solving the theoretical flight trajectory of the aircraft, and generating a lift-mass coupling deviation matrix; S4: calculating the turbulence compensation coefficient, and correcting the basic lift coefficient of S2; S5: inversely calculating the lift coefficient compensation amount and the mass compensation amount; and S6: outputting the six-degree-of-freedom motion state of the aircraft. Through the fusion of the environmental disturbance compensation and the trajectory error feedback correction mechanism, the present application realizes the real-time correction and linkage update of the lift coefficient, the mass and the moment of inertia, thereby significantly improving the accuracy and the dynamic adaptive ability of the aircraft digital twinning simulation.

Description

Technical Field

[0001] This invention relates to the field of aircraft simulation and digital twin technology, and in particular to an aircraft motion simulation method based on digital twin. Background Technology

[0002] As aircraft flight control systems become more intelligent and complex, digital twin technology is increasingly being used in flight performance simulation, health status assessment, and flight safety assurance. Digital twin models can achieve real-time mapping and prediction of aircraft status by synchronously integrating flight data, dynamic models, and physical parameters.

[0003] However, most current aircraft simulation systems still rely on static parameters as input, making it difficult to handle the dynamic evolution of flight states under complex flight environments. This is especially true when factors such as changes in angle of attack, sideslip, fuel consumption reduction, and turbulent disturbances are involved. The lack of dynamic update mechanisms for lift coefficients, mass, and moment of inertia leads to the accumulation of six-degree-of-freedom motion simulation biases, affecting prediction accuracy and control response. Therefore, a digital twin-based aircraft motion simulation method is urgently needed to address these issues. Summary of the Invention

[0004] To achieve the above objectives, the present invention provides an aircraft motion simulation method based on digital twins.

[0005] A method for simulating aircraft motion based on digital twins includes the following steps:

[0006] S1: Real-time acquisition of aircraft angle of attack, sideslip angle, fuel quantity, and environmental turbulence intensity;

[0007] S2: Based on the angle of attack and sideslip angle of S1, the basic lift coefficient and drag coefficient are matched from the aerodynamic database, and the real-time mass and moment of inertia of the aircraft are calculated according to the fuel quantity.

[0008] S3: Input the basic lift coefficient and real-time mass obtained in S2 into the kinematics solver to solve the theoretical flight trajectory of the aircraft, and compare the theoretical trajectory with the GPS measured trajectory to generate the lift-mass coupling deviation matrix;

[0009] S4: When the intensity of environmental turbulence exceeds the preset threshold, calculate the turbulence compensation coefficient and correct the basic lift coefficient of S2;

[0010] S5: Based on the lift-mass coupling deviation matrix of S3, calculate the lift coefficient compensation and mass compensation in reverse, and correct the lift coefficient based on S4, while simultaneously correcting the real-time mass and moment of inertia parameters.

[0011] S6: Load the lift coefficient, real-time mass, and moment of inertia corrected in S5 into the digital twin and output the six-degree-of-freedom motion state of the aircraft.

[0012] Optionally, S1 specifically includes:

[0013] S11: The aircraft's angle of attack is acquired in real time via an onboard inertial measurement unit (IMU), which is the angle between the aircraft's longitudinal axis and the relative airflow. The IMU includes an accelerometer and a gyroscope, and outputs continuous angle measurements. ;

[0014] S12: The sideslip angle of the aircraft is acquired in real time by a rate sensor installed on the side of the fuselage. The sideslip angle is the angle between the longitudinal axis of the fuselage in the horizontal plane and the actual direction of motion. The rate sensor outputs continuous angle measurements. ;

[0015] S13: Real-time detection of fuel volume in aircraft fuel tanks via airborne fuel mass sensors, calculation of fuel quantity based on fuel density parameters, and output of current fuel mass value m;

[0016] S14: Real-time data on airflow velocity fluctuations outside the aircraft are collected through environmental sensors. The standard deviation of velocity change within a predetermined time interval is calculated using a sliding window root mean square algorithm, and the standard deviation is used as the measurement value of environmental turbulence intensity T.

[0017] Optionally, S2 specifically includes:

[0018] S21: The angle of attack obtained in S1 With sideslip angle As input variables, a two-dimensional index vector is constructed, which is then input into a pre-defined aerodynamic database, and the matched basic lift coefficient is output. With the basic resistance coefficient ;

[0019] S22: The fuel mass obtained in S1 Aircraft structural empty weight The summation yields the aircraft's current real-time mass. ;

[0020] S23: Real-time quality based on calculation By combining the mass distribution and configuration parameters of various aircraft components, the moment of inertia of the aircraft can be estimated in real time. The calculation formula is: ,in, This represents the moment of inertia of an aircraft. Indicates the first The quality of each component Indicates the first The distance from the center of mass of the component to the axis of rotation. This refers to the number of components.

[0021] Optionally, S3 specifically includes:

[0022] S31: The basic lift coefficient obtained in S2 With real-time quality As input variables, the kinematics solver combines the aircraft's structural parameters, gravitational acceleration, and aerodynamic configuration parameters to solve for the acceleration, velocity, and displacement responses per unit time, generating the corresponding spatial trajectory point sequence and constructing the aircraft's theoretical flight trajectory.

[0023] S32: Obtain continuous three-dimensional position information from the aircraft's onboard GPS module and construct a sequence of measured trajectory points that correspond one-to-one with the theoretical flight trajectory timestamps;

[0024] S33: After aligning the theoretical flight trajectory with the GPS measured trajectory according to the timestamp, calculate the positional difference between each corresponding trajectory point in three-dimensional space, and extract the vertical displacement difference, horizontal displacement difference and total displacement error at each time point;

[0025] S34: Construct a lift-mass coupling deviation matrix based on the displacement error at each time point and the input lift coefficient and mass parameters. The lift-mass deviation matrix uses the time series as the row index and the coupling relationship between trajectory error and physical parameters as the column vector.

[0026] Optionally, S31 specifically includes:

[0027] S311: Based on the basic lift coefficient Real-time quality Based on flight speed and wing area, calculate the lift of the aircraft per unit time in the current attitude. ;

[0028] S312: Based on the aircraft's real-time quality and lift Calculate the vertical acceleration And simultaneously based on the drag coefficient Calculate the horizontal drag to obtain the horizontal acceleration. ;

[0029] S313: Based on the current velocity and acceleration values, the velocity and displacement per unit time are iteratively updated using the difference integral method, and solved separately. The formula is:

[0030] ;

[0031] ,in, and These represent the velocity and position at the previous moment, respectively. , These represent the velocity and position at the current moment, respectively. Acceleration in the current direction; For time step;

[0032] S314: Update the position within a unit of time. By adding the points to the trajectory point sequence and iterating continuously to obtain multiple consecutive position points, the complete theoretical flight trajectory of the aircraft under the current input conditions is finally constructed.

[0033] Optionally, S4 specifically includes:

[0034] S41: Obtain the environmental turbulence intensity value measured in real time in S1. and with the preset turbulence intensity threshold Perform a comparison; if the conditions are met... If so, proceed to the following compensation calculation process;

[0035] S42: Based on the actual turbulence intensity With set threshold The relative amplitude difference between them is used to calculate the turbulence disturbance influence factor under the current operating condition. ;

[0036] S43: Disturbance factor Substitute into the lift coefficient compensation function to calculate the turbulence compensation coefficient. Specifically, it is determined by the following linear relationship: ,in, This is a lift coefficient compensation factor related to the aircraft model;

[0037] S44: The basic lift coefficient obtained in S2 With compensation coefficient By performing superposition corrections, the corrected lift coefficient is calculated. The formula is: .

[0038] Optionally, S5 specifically includes:

[0039] S51: Read the lift-mass coupling deviation matrix generated in S3;

[0040] S52: Based on the lift-mass coupling deviation matrix, the minimum error fitting method is used to analyze the trajectory error residual. Combined with the deviation gradient change trend within the time period, the lift coefficient compensation and mass compensation under the current flight state are calculated respectively.

[0041] S53: Using the lift coefficient already corrected in S4 as the base value, the lift coefficient compensation amount obtained in S52 is superimposed on it to generate the final corrected lift coefficient.

[0042] S54: Based on the mass compensation amount determined in S52, update the current mass value in real time, and input the corrected mass value into the aircraft mass-moment of inertia mapping table to update the aircraft's current moment of inertia parameter.

[0043] Optionally, S52 specifically includes:

[0044] S521: Based on the lift-mass coupling deviation matrix in S3, the least squares method is used to perform regression analysis on the spatial error residual sequence of the theoretical trajectory and the GPS measured trajectory to determine the optimal matching relationship between the current trajectory error and the lift coefficient deviation, and to calculate the lift coefficient compensation amount. The calculation formula is:

[0045] ,in, For the first Location of GPS measured trajectory points at any given time; For the first Position of the theoretical flight trajectory point at any given moment; The sensitivity of the theoretical trajectory point to the lift coefficient; This represents the total number of trajectory sampling points;

[0046] S522: By combining the gradient change of trajectory error over a time period, analyze the trend of residual variation with quality parameters, and calculate the quality compensation amount using the least squares fitting method. The specific formula is as follows:

[0047] ,in; For the first Location of GPS measured trajectory points at any given time; For the first Position of the theoretical flight trajectory point at any given moment; This represents the sensitivity of the theoretical trajectory point to the mass parameter.

[0048] Optionally, S53 specifically includes:

[0049] S531: Extract the corrected lift coefficient calculated in S4 ; and the lift coefficient compensation amount With the corrected lift coefficient Numerical superposition is performed to generate the final corrected lift coefficients used for motion calculation. The formula is: .

[0050] Optionally, S6 specifically includes:

[0051] S61: The final corrected lift coefficient, corrected real-time mass, and moment of inertia obtained in S5 are used as input parameters and loaded into the flight physics modeling unit of the digital twin, respectively.

[0052] S62: Call the six-degree-of-freedom dynamics simulation module of the digital twin. Based on the loaded lift coefficient, mass and moment of inertia, combined with the aircraft structural parameters and current flight environment data, solve the three translational degrees of freedom and three rotational degrees of freedom in sequence to form a complete set of six-degree-of-freedom state variables.

[0053] S63: Organizes the six-degree-of-freedom motion states output from S62 into a continuous simulation data stream according to timestamps, and feeds it back to the aircraft monitoring interface in real time to achieve synchronous digital twin simulation with the actual flight process.

[0054] The beneficial effects of this invention are:

[0055] This invention achieves precise modeling of aircraft flight status by acquiring aircraft angle of attack, sideslip angle, fuel quantity, and environmental turbulence intensity in real time, and dynamically matching lift and drag coefficients based on an aerodynamic database. At the same time, it adopts a compensation mechanism that combines environmental disturbance compensation with closed-loop correction based on trajectory error feedback, which effectively improves the dynamic correction capability of lift coefficient, mass, and moment of inertia parameters, ensuring the high adaptability and accuracy of the simulation model to complex working conditions and dynamic flight processes.

[0056] This invention, by employing lift-mass coupling deviation matrix residual analysis and mass-inertia mapping table, enables multi-parameter closed-loop linkage correction between flight data and simulation models, promoting the physical consistency and temporal stability of digital twins in six-degree-of-freedom motion simulation, and providing a solid technical foundation for flight safety management and intelligent decision-making. Attached Figure Description

[0057] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0058] Figure 1 This is a schematic diagram of an aircraft motion simulation method according to an embodiment of the present invention;

[0059] Figure 2 This is a schematic diagram of the reverse calculation and correction method according to an embodiment of the present invention. Detailed Implementation

[0060] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. It should also be noted that, to make the embodiments more comprehensive, the following embodiments are the best and preferred embodiments, and those skilled in the art can use other alternative methods to implement some well-known technologies; moreover, the accompanying drawings are only for more specific description of the embodiments and are not intended to specifically limit the present invention.

[0061] It should be noted that the use of terms such as "an embodiment," "an embodiment," "an exemplary embodiment," and "some embodiments" in the specification indicates that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, when a specific feature, structure, or characteristic is described in connection with an embodiment, implementing such a feature, structure, or characteristic in conjunction with other embodiments (whether explicitly described or not) should be within the knowledge of those skilled in the art.

[0062] Generally, terms can be understood at least partly from their use in context. For example, depending at least partly on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in a singular sense, or a combination of features, structures, or characteristics in a plural sense. Additionally, the term "based on" can be understood not necessarily to convey an exclusive set of factors, but rather, alternatively, depending at least partly on the context, to allow for the presence of other factors that are not necessarily explicitly described.

[0063] like Figures 1-2 As shown, an aircraft motion simulation method based on digital twins includes the following steps:

[0064] S1: Real-time acquisition of aircraft angle of attack, sideslip angle, fuel quantity, and environmental turbulence intensity;

[0065] S2: Based on the angle of attack and sideslip angle of S1, the basic lift coefficient and drag coefficient are matched from the aerodynamic database, and the real-time mass and moment of inertia of the aircraft are calculated according to the fuel quantity.

[0066] S3: Input the basic lift coefficient and real-time mass obtained in S2 into the kinematics solver to solve the theoretical flight trajectory of the aircraft, and compare the theoretical trajectory with the GPS measured trajectory to generate the lift-mass coupling deviation matrix;

[0067] S4: When the intensity of environmental turbulence exceeds the preset threshold, calculate the turbulence compensation coefficient and correct the basic lift coefficient of S2 to compensate for the influence of external disturbances.

[0068] S5: Based on the lift-mass coupling deviation matrix of S3, calculate the lift coefficient compensation and mass compensation in reverse, and correct the lift coefficient based on S4, while simultaneously correcting the real-time mass and moment of inertia parameters.

[0069] S6: Load the lift coefficient, real-time mass, and moment of inertia corrected in S5 into the digital twin and output the six-degree-of-freedom motion state of the aircraft.

[0070] S1 specifically includes:

[0071] S11: The aircraft's angle of attack is acquired in real time via an onboard inertial measurement unit (IMU). The angle of attack is the angle between the aircraft's longitudinal axis and the relative airflow. The IMU includes an accelerometer and a gyroscope, and outputs continuous angle measurements. ;

[0072] S12: The aircraft's sideslip angle is acquired in real time by a rate sensor installed on the side of the fuselage. The sideslip angle is the angle between the aircraft's longitudinal axis in the horizontal plane and the actual direction of motion. The rate sensor outputs continuous angle measurements. ;

[0073] S13: Real-time detection of fuel volume in the aircraft's fuel tank using an onboard fuel mass sensor, calculation of fuel quantity based on fuel density parameters, and output of the current fuel mass value m; the fuel quantity calculation formula is: ,in, Indicates the current fuel quality; Indicates the current fuel volume; Indicates fuel density;

[0074] S14: Real-time acquisition of airflow velocity fluctuation data outside the aircraft is achieved through environmental sensors. The standard deviation of velocity change within a predetermined time interval is calculated using the sliding window root mean square algorithm. The standard deviation is used as the measured value of environmental turbulence intensity T. Through the above steps, high-precision real-time acquisition of aircraft angle of attack, sideslip angle, fuel quantity and environmental turbulence intensity is achieved, providing a stable and reliable raw data foundation for subsequent aerodynamic parameter matching and motion simulation.

[0075] S2 specifically includes:

[0076] S21: The angle of attack obtained in S1 With sideslip angle As input variables, a two-dimensional index vector is constructed, which is then input into a pre-defined aerodynamic database, and the matched basic lift coefficient is output. With the basic resistance coefficient The aerodynamic database uses angle of attack and sideslip angle as dual index keys and pre-stores aerodynamic coefficient matrices covering different flight states.

[0077] Table 1. Pneumatic Database

[0078]

[0079] Table 1 forms a two-dimensional index lookup table. When the angle of attack α and sideslip angle β provided by S1 are input, the system automatically locates the corresponding row and extracts the corresponding Cl0 and Cd0 as input parameters for subsequent motion calculations. If the input parameters are not integer values ​​in the table, they can be interpolated between four adjacent points in the table using bilinear interpolation to ensure the continuity of simulation data. By constructing a structured aerodynamic database indexed by angle of attack and sideslip angle, and setting corresponding value ranges for lift and drag coefficients, the aircraft can quickly retrieve matching aerodynamic parameters under various attitude conditions, avoiding redundant calculations during real-time simulation.

[0080] S22: The fuel mass obtained in S1 Aircraft structural empty weight The summation yields the aircraft's current real-time mass. The calculation formula is as follows: ,in, Indicates the current total mass of the aircraft. Indicates the empty weight of the aircraft structure. The current fuel mass calculated in S13;

[0081] S23: Real-time quality based on calculation By combining the mass distribution and configuration parameters of various aircraft components, the moment of inertia of the aircraft can be estimated in real time. The calculation formula is: ,in, This represents the moment of inertia of an aircraft. Indicates the first The quality of each component Indicates the first The distance from the center of mass of the component to the axis of rotation. The above steps allow for the accurate acquisition of aerodynamic coefficients based on flight attitude parameters. Simultaneously, by combining fuel data, dynamic updates of aircraft mass and moment of inertia can be achieved, providing data support for subsequent trajectory calculation and simulation accuracy optimization.

[0082] S3 specifically includes:

[0083] S31: The basic lift coefficient obtained in S2 With real-time quality As input variables, the kinematics solver combines the aircraft's structural parameters, gravitational acceleration, and aerodynamic configuration parameters to solve for the acceleration, velocity, and displacement responses per unit time, generating the corresponding spatial trajectory point sequence and constructing the aircraft's theoretical flight trajectory.

[0084] S32: Obtain continuous three-dimensional position information from the aircraft's onboard GPS module and construct a sequence of measured trajectory points that correspond one-to-one with the theoretical flight trajectory timestamps;

[0085] S33: After aligning the theoretical flight trajectory with the GPS measured trajectory according to the timestamp, calculate the positional difference between each corresponding trajectory point in three-dimensional space, and extract the vertical displacement difference, horizontal displacement difference and total displacement error at each time point;

[0086] S34: Construct a lift-mass coupling deviation matrix based on the displacement error at each time point and the input lift coefficient and mass parameters. The lift-mass deviation matrix uses the time series as the row index and the coupling relationship between trajectory error and physical parameters as the column vector. It is used to reflect the coupling error characteristics between the current lift coefficient and mass setting and the actual flight state. Through the above steps, the output results of the kinematic prediction model can be dynamically compared with the actual flight data, and an error matrix containing the coupling effect of lift and mass parameters can be formed. This provides a high-precision data foundation for subsequent feedback compensation calculations, thereby significantly improving the model credibility and correction accuracy of the simulation system.

[0087] S31 specifically includes:

[0088] S311: Based on the basic lift coefficient Real-time quality Based on flight speed and wing area, calculate the lift of the aircraft per unit time in the current attitude. Lift is used to determine the acceleration component in the vertical direction. The formula for calculating lift is: ,in, Indicates lift; Indicates air density; Indicates flight speed; Indicates wing area; Indicates the basic lift coefficient;

[0089] S312: Based on the aircraft's real-time quality and lift Calculate the vertical acceleration And simultaneously based on the drag coefficient Calculate the horizontal drag to obtain the horizontal acceleration. Solve using the following formulas respectively: ; ,in, Indicates acceleration in the vertical direction; Indicates acceleration in the horizontal direction; Representing resistance, from the formula calculate; Represents gravitational acceleration;

[0090] S313: Based on the current velocity and acceleration values, the velocity and displacement per unit time are iteratively updated using the difference integral method, and solved separately. The formula is:

[0091] ;

[0092] ,in, and These represent the velocity and position at the previous moment, respectively. , These represent the velocity and position at the current moment, respectively. Acceleration in the current direction; For time step;

[0093] S314: Update the position within a unit of time. By adding the trajectory point sequence and iterating continuously to obtain multiple consecutive position points, a complete theoretical flight trajectory of the aircraft under the current input conditions is finally constructed. Through the above steps, combined with the aerodynamic characteristics of lift and drag, aircraft structural parameters and mass information, dynamic modeling of the acceleration and motion response of the aircraft under actual force conditions is realized, thereby constructing a high-precision and continuous theoretical flight trajectory sequence, which effectively enhances the physical consistency and temporal predictability of the digital twin simulation model.

[0094] S4 specifically includes:

[0095] S41: Obtain the environmental turbulence intensity value measured in real time in S1. and with the preset turbulence intensity threshold Perform a comparison; if the conditions are met... If so, proceed to the following compensation calculation process;

[0096] S42: Based on the actual turbulence intensity With set threshold The relative amplitude difference between them is used to calculate the turbulence disturbance influence factor under the current operating condition. The formula for calculating the disturbance factor is: ,in, It is a dimensionless turbulence disturbance factor used to quantify the proportion of disturbance intensity in the current environment compared to stable flight conditions;

[0097] S43: Disturbance factor Substitute into the lift coefficient compensation function to calculate the turbulence compensation coefficient. Specifically, it is determined by the following linear relationship: ,in, This is the lift coefficient compensation ratio factor related to the aircraft model, and its value is preset by flight test or simulation calibration;

[0098] Lift coefficient compensation ratio factor The calculation formula is as follows: ,in, This represents the decrease in lift coefficient obtained by actual measurement or simulation under reference turbulent conditions. The disturbance factor corresponding to this reference operating condition is calculated as follows: ,in, Indicates the turbulence intensity during a reference test or simulation; The turbulence intensity threshold set for the system;

[0099] S44: The basic lift coefficient obtained in S2 With compensation coefficient By performing superposition corrections, the corrected lift coefficient is calculated. The formula is: Through the above steps, when the intensity of environmental turbulence exceeds the set range, the appropriate compensation amount can be calculated based on the disturbance intensity to dynamically correct the lift coefficient, thereby improving the robustness and adaptability of the simulation model to complex external airflow conditions and enhancing the physical fitting ability of the digital twin to non-steady flight states.

[0100] S5 specifically includes:

[0101] S51: Read the lift-mass coupling deviation matrix generated in S3. The deviation matrix is ​​arranged in time series and records the spatial error value between the theoretical flight trajectory and the GPS measured trajectory, as well as the corresponding input parameter information. It is used to reflect the deviation response relationship between the basic lift coefficient and the real-time mass under different flight conditions.

[0102] S52: Based on the lift-mass coupling deviation matrix, the minimum error fitting method is used to analyze the trajectory error residual. Combined with the deviation gradient change trend within a time period, the lift coefficient compensation and mass compensation in the current flight state are calculated respectively, so as to simultaneously correct the lift deviation and the mass error caused by load changes.

[0103] S53: Using the lift coefficient already corrected in S4 as the base value, the lift coefficient compensation obtained in S52 is superimposed on it to generate the final corrected lift coefficient, which is used as the input aerodynamic parameter for the next stage of motion simulation.

[0104] S54: Based on the mass compensation amount determined in S52, the current mass value is updated in real time, and the corrected mass value is input into the aircraft mass-moment of inertia mapping table to update the current moment of inertia parameter of the aircraft. Through the above steps, dynamic coupling analysis between flight trajectory and aerodynamic parameters can be introduced on the basis of existing feedforward compensation, so as to realize fine feedback correction of lift coefficient and mass, and adjust moment of inertia in linkage, so that the simulation system has the ability to update multiple parameters in a closed loop.

[0105] Table 2 Aircraft Mass-Moment of Inertia Mapping Table

[0106]

[0107] In Table 2 above, the corrected real-time mass represents the total mass of the aircraft at the current moment, obtained by adding the structural empty weight and the real-time fuel mass, corresponding to the corrected mass parameters; the wing moment of inertia I1 is the moment of inertia of the wing about its center of mass axis; the fuselage moment of inertia I2 is the moment of inertia of the aircraft fuselage relative to the central axis, used to reflect the inertial response to changes in fuselage weight; the vertical tail moment of inertia I3 is the moment of inertia of the vertical tail section; the overall aircraft moment of inertia I... t The total moment of inertia of the aircraft is the weighted or summed result of I1, I2, and I3, which serves as the key input parameter for subsequent six-degree-of-freedom motion calculations.

[0108] S52 specifically includes:

[0109] S521: Based on the lift-mass coupling deviation matrix in S3, the least squares method is used to perform regression analysis on the spatial error residual sequence of the theoretical trajectory and the GPS measured trajectory to determine the optimal matching relationship between the current trajectory error and the lift coefficient deviation, and to calculate the lift coefficient compensation amount. The calculation formula is:

[0110] ,in, For the first Location of GPS measured trajectory points at any given time; For the first Position of the theoretical flight trajectory point at any given moment; The sensitivity of the theoretical trajectory point to the lift coefficient; This represents the total number of trajectory sampling points;

[0111] S522: By combining the gradient change of trajectory error over a time period, analyze the trend of residual variation with quality parameters, and calculate the quality compensation amount using the least squares fitting method. The specific formula is as follows:

[0112] ,in; For the first Location of GPS measured trajectory points at any given time; For the first Position of the theoretical flight trajectory point at any given moment; The sensitivity of theoretical trajectory points to mass parameters is determined by the above steps. Combined with the sensitivity regression analysis of trajectory error residuals, the deviation between lift coefficient and mass parameters can be effectively distinguished and quantitatively compensated, enabling the simulation model to dynamically respond to changes in flight state and improve the accuracy and adaptability of the digital twin system.

[0113] S53 specifically includes:

[0114] S531: Extract the corrected lift coefficient calculated in S4 ; and the lift coefficient compensation amount With the corrected lift coefficient Numerical superposition is performed to generate the final corrected lift coefficients used for motion calculation. The formula is: .

[0115] S6 specifically includes:

[0116] S61: The final corrected lift coefficient obtained in S5 Corrected real-time mass and moment of inertia As input parameters, they are loaded into the flight physics modeling unit of the digital twin to ensure that all dynamic and aerodynamic input parameters strictly correspond to the current aircraft state;

[0117] S62: Invoke the six-degree-of-freedom dynamics simulation module of the digital twin, and based on the loaded lift coefficient, mass, and moment of inertia, combined with the aircraft structural parameters and current flight environment data, sequentially solve the three translational degrees of freedom. , , The six degrees of freedom (position and velocity) and three rotational degrees of freedom (pitch, yaw, roll angle and angular velocity) form a complete set of six-degree-of-freedom state variables;

[0118] S63: The six-degree-of-freedom motion states output from S62 are organized into a continuous simulation data stream according to timestamps and fed back to the aircraft monitoring interface in real time, realizing synchronous digital twin simulation with the actual flight process. This facilitates the system's comprehensive prediction and visualization of the flight state. Through the above steps, the corrected lift coefficient, real-time mass, and moment of inertia can be fully loaded into the digital twin simulation platform and drive the six-degree-of-freedom dynamics calculation, realizing high-fidelity dynamic reconstruction of the aircraft's spatial attitude and motion state. This provides accurate simulation data support for subsequent flight control strategy adjustments and risk warning analysis.

[0119] This invention encompasses any substitutions, modifications, equivalent methods, and solutions made within the spirit and scope of this invention. To provide the public with a thorough understanding of this invention, specific details are described in detail in the following preferred embodiments; however, those skilled in the art will fully understand the invention even without these details. Furthermore, to avoid unnecessary misunderstanding of the essence of this invention, well-known methods, processes, procedures, components, and circuits are not described in detail.

[0120] 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 and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for simulating aircraft motion based on digital twins, characterized in that, Includes the following steps: S1: Real-time acquisition of aircraft angle of attack Sideslip angle Fuel quality and environmental turbulence intensity ; S2: Angle of attack based on S1 With sideslip angle Matching the basic lift coefficient from the aerodynamic database With the basic resistance coefficient At the same time, based on fuel quality Calculate the real-time quality of aircraft and moment of inertia; specifically including: S21: The angle of attack obtained in S1 With sideslip angle As input variables, a two-dimensional index vector is constructed, which is then input into a pre-defined aerodynamic database, and the matched basic lift coefficient is output. With the basic resistance coefficient ; S22: The fuel mass obtained in S1 Aircraft structural empty weight The summation yields the aircraft's current real-time mass. ; S23: Real-time quality based on calculation By combining the mass distribution and configuration parameters of various aircraft components, the moment of inertia of the aircraft can be estimated in real time. The calculation formula is: ,in, This represents the moment of inertia of an aircraft. Indicates the first The quality of each component Indicates the first The distance from the center of mass of the component to the axis of rotation. Number of components; S3: Input the basic lift coefficient and real-time mass obtained in S2 into the kinematics solver to solve the theoretical flight trajectory of the aircraft, and compare the theoretical trajectory with the GPS measured trajectory to generate the lift-mass coupling deviation matrix; S4: When the environmental turbulence intensity exceeds a preset threshold, calculate the turbulence compensation coefficient and correct the basic lift coefficient of S2; specifically including: S41: Obtain the environmental turbulence intensity value measured in real time in S1. and with the preset turbulence intensity threshold Perform a comparison; if the conditions are met... If so, proceed to the following compensation calculation process; S42: Based on the actual turbulence intensity With set threshold The relative amplitude difference between them is used to calculate the turbulence disturbance influence factor under the current operating condition. ; S43: Disturbance factor Substitute into the lift coefficient compensation function to calculate the turbulence compensation coefficient. Specifically, it is determined by the following linear relationship: ,in, This is a lift coefficient compensation factor related to the aircraft model; S44: The basic lift coefficient obtained in S2 With compensation coefficient By performing superposition corrections, the corrected lift coefficient is calculated. The formula is: ; S5: Based on the lift-mass coupling deviation matrix of S3, calculate the lift coefficient compensation and mass compensation in reverse, and correct the lift coefficient based on S4, while simultaneously correcting the real-time mass and moment of inertia parameters; specifically including: S51: Read the lift-mass coupling deviation matrix generated in S3; S52: Based on the lift-mass coupling deviation matrix, the minimum error fitting method is used to analyze the trajectory error residual. Combined with the deviation gradient change trend within the time period, the lift coefficient compensation and mass compensation under the current flight state are calculated respectively. S53: Using the lift coefficient already corrected in S4 as the base value, the lift coefficient compensation amount obtained in S52 is superimposed on it to generate the final corrected lift coefficient. S54: Based on the mass compensation amount determined in S52, update the current mass value in real time, and input the corrected mass value into the aircraft mass-moment of inertia mapping table to update the aircraft's current moment of inertia parameter; S6: Load the lift coefficient, real-time mass, and moment of inertia corrected in S5 into the digital twin and output the six-degree-of-freedom motion state of the aircraft.

2. The aircraft motion simulation method based on digital twins according to claim 1, characterized in that, S1 specifically includes: S11: The aircraft's angle of attack is acquired in real time via an onboard inertial measurement unit (IMU), which is the angle between the aircraft's longitudinal axis and the relative airflow. The IMU includes an accelerometer and a gyroscope, and outputs continuous angle measurements. ; S12: The sideslip angle of the aircraft is acquired in real time by a rate sensor installed on the side of the fuselage. The sideslip angle is the angle between the longitudinal axis of the fuselage in the horizontal plane and the actual direction of motion. The rate sensor outputs continuous angle measurements. ; S13: Real-time detection of fuel volume in the aircraft's fuel tank using onboard fuel mass sensors, calculation of fuel quantity based on fuel density parameters, and output of the current fuel mass value. ; S14: Real-time data on airflow velocity fluctuations outside the aircraft are collected through environmental sensors. The standard deviation of velocity change within a predetermined time interval is calculated using a sliding window root mean square algorithm, and the standard deviation is used as the measurement value of environmental turbulence intensity T.

3. The aircraft motion simulation method based on digital twins according to claim 1, characterized in that, S3 specifically includes: S31: The basic lift coefficient obtained in S2 With real-time quality As input variables, the kinematics solver combines the aircraft's structural parameters, gravitational acceleration, and aerodynamic configuration parameters to solve for the acceleration, velocity, and displacement responses per unit time, generating the corresponding spatial trajectory point sequence and constructing the aircraft's theoretical flight trajectory. S32: Obtain continuous three-dimensional position information from the aircraft's onboard GPS module and construct a sequence of measured trajectory points that correspond one-to-one with the theoretical flight trajectory timestamps; S33: After aligning the theoretical flight trajectory with the GPS measured trajectory according to the timestamp, calculate the positional difference between each corresponding trajectory point in three-dimensional space, and extract the vertical displacement difference, horizontal displacement difference and total displacement error at each time point; S34: Construct a lift-mass coupling deviation matrix based on the displacement error at each time point and the input lift coefficient and mass parameters. The lift-mass deviation matrix uses the time series as the row index and the coupling relationship between trajectory error and physical parameters as the column vector.

4. The aircraft motion simulation method based on digital twins according to claim 3, characterized in that, S31 specifically includes: S311: Based on the basic lift coefficient Real-time quality Based on flight speed and wing area, calculate the lift of the aircraft per unit time in the current attitude. ; S312: Based on the aircraft's real-time quality and lift Calculate the vertical acceleration And simultaneously based on the drag coefficient Calculate the horizontal drag to obtain the horizontal acceleration. ; S313: Based on the current velocity and acceleration values, the velocity and displacement per unit time are iteratively updated using the difference integral method, and solved separately. The formula is: ； ,in, and These represent the velocity and position at the previous moment, respectively. , These represent the velocity and position at the current moment, respectively. Acceleration in the current direction; For time step; S314: Update the position within a unit of time. By adding the points to the trajectory point sequence and iterating continuously to obtain multiple consecutive position points, the complete theoretical flight trajectory of the aircraft under the current input conditions is finally constructed.

5. The aircraft motion simulation method based on digital twin according to claim 1, characterized in that, S52 specifically includes: S521: Based on the lift-mass coupling deviation matrix in S3, the least squares method is used to perform regression analysis on the spatial error residual sequence of the theoretical trajectory and the GPS measured trajectory to determine the optimal matching relationship between the current trajectory error and the lift coefficient deviation, and to calculate the lift coefficient compensation amount. The calculation formula is: ,in, For the first Location of GPS measured trajectory points at any given time; For the first Position of the theoretical flight trajectory point at any given moment; The sensitivity of the theoretical trajectory point to the lift coefficient; This represents the total number of trajectory sampling points; S522: By combining the gradient change of trajectory error over a time period, analyze the trend of residual variation with quality parameters, and calculate the quality compensation amount using the least squares fitting method. The specific formula is as follows: ,in; For the first Location of GPS measured trajectory points at any given time; For the first Position of the theoretical flight trajectory point at any given moment; This represents the sensitivity of the theoretical trajectory point to the mass parameter.

6. The aircraft motion simulation method based on digital twin according to claim 5, characterized in that, Specifically, S53 includes: S531: Extract the corrected lift coefficient calculated in S4 ; and the lift coefficient compensation amount With the corrected lift coefficient Numerical superposition is performed to generate the final corrected lift coefficients used for motion calculation. The formula is: .

7. The aircraft motion simulation method based on digital twin according to claim 1, characterized in that, S6 specifically includes: S61: The final corrected lift coefficient, corrected real-time mass, and moment of inertia obtained in S5 are used as input parameters and loaded into the flight physics modeling unit of the digital twin, respectively. S62: Call the six-degree-of-freedom dynamics simulation module of the digital twin. Based on the loaded lift coefficient, mass and moment of inertia, combined with the aircraft structural parameters and current flight environment data, solve the three translational degrees of freedom and three rotational degrees of freedom in sequence to form a complete set of six-degree-of-freedom state variables. S63: Organizes the six-degree-of-freedom motion states output from S62 into a continuous simulation data stream according to timestamps, and feeds it back to the aircraft monitoring interface in real time to achieve synchronous digital twin simulation with the actual flight process.

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