A method for identifying aerodynamic parameters of a first stage flight section of a launch vehicle and related equipment

Abstract

The application discloses a launch vehicle first-stage flight section aerodynamic parameter identification method and related equipment, and relates to the field of launch vehicles.The method comprises the following steps: calculating the attack angle and sideslip angle of the first-stage flight section of the rocket according to the measured wind field data and flight telemetry data on the launch day; obtaining angular acceleration information according to the angular velocity information in the flight telemetry data; calculating the rocket body combined moment information according to the angular acceleration information and the rocket body rotational inertia; calculating the rocket body moment coefficient information according to the rocket body combined moment information, dynamic pressure information and rocket body size information, wherein the rocket body size information comprises rocket body reference area information and rocket body length information; performing reverse interpolation operation on the known aerodynamic parameters and the aerodynamic moment coefficient to obtain the rudder deflection control quantity, wherein the known aerodynamic parameters comprise the attack angle, the sideslip angle and the Mach number, and the rudder deflection control quantity comprises the pitch rudder deflection control quantity, the yaw rudder deflection control quantity and the roll rudder deflection control quantity; and comparing the rudder deflection control quantity with the actual flight rudder deflection to judge the aerodynamic parameters.

Description

TECHNICAL FIELD

[0001] The present specification relates to the field of launch vehicles, and more specifically, to a method for identifying aerodynamic parameters of a launch vehicle in a first flight phase and related equipment. BACKGROUND

[0002] When a launch vehicle accelerates through the atmosphere in the active phase, the aerodynamic force and moment generated by the airflow on the vehicle body have a great influence on the stability of the launch vehicle flight. During the flight, the vehicle body needs to withstand large axial and lateral overloads, dynamic pressure, and thermal environment, which puts requirements on the vehicle body structure. The aerodynamic characteristics of the rocket determine the trajectory shape and related motion parameters in the active phase, and these motion parameters, as inputs of the rocket flight control system, affect the design of the flight control system; the dynamic pressure and overload, as inputs of the rocket structure system design, affect the design of the vehicle body structure. Therefore, the accuracy of the aerodynamic parameters of the rocket plays a key role in the flight of the rocket in the atmosphere. SUMMARY

[0003] A series of simplified concepts are introduced in the summary section, which will be further described in detail in the specific embodiment section. The summary section of the present application does not mean to attempt to limit the key features and essential technical features of the claimed technical solutions, nor to determine the protection scope of the claimed technical solutions.

[0004] In a first aspect, the present application provides a method for identifying aerodynamic parameters of a launch vehicle in a first flight phase, the method comprising:

[0005] According to the measured wind field data and flight telemetry data on the launch day, the attack angle and sideslip angle of the first flight phase of the rocket are calculated;

[0006] According to the angular velocity information in the flight telemetry data, the angular acceleration information is obtained;

[0007] According to the angular acceleration information and the moment of inertia of the vehicle body, the vehicle body moment information is calculated;

[0008] According to the vehicle body moment information, the dynamic pressure information, and the vehicle body size information, the vehicle body moment coefficient information is calculated, wherein the vehicle body size information includes vehicle body reference area information and vehicle body length information;

[0009] According to the known aerodynamic parameters and the aerodynamic moment coefficient, a reverse interpolation operation is performed to obtain the rudder deflection control amount, wherein the known aerodynamic parameters include the attack angle, the sideslip angle, and the Mach number, and the rudder deflection control amount includes the pitch rudder deflection control amount, the yaw rudder deflection control amount, and the roll rudder deflection control amount;

[0010] Based on the comparison between the rudder deflection control amount and the actual flight rudder deflection, the aerodynamic parameters are evaluated.

[0011] In an implementation, the method further comprises:

[0012] In a case where the rudder deflection control amount and the actual flight-time rudder deflection exceed a preset threshold, determining a moment coefficient correction amount based on a rudder deflection difference between the rudder deflection control amount and the actual flight-time rudder deflection and a moment coefficient correction coefficient;

[0013] Correcting the aerodynamic moment coefficient based on the moment coefficient correction amount, so that the rudder deflection difference between the rudder deflection control amount and the actual flight-time rudder deflection is reduced to within the preset threshold.

[0014] In an implementation, the method of calculating the angle of attack and the sideslip angle of the rocket first-stage flight section according to the measured wind field data and the flight telemetry data on the launch day comprises:

[0015] Calculating the relative velocity of the rocket body relative to the airflow according to the measured wind field data and the flight telemetry data on the launch day;

[0016] Determining the components of the velocity of the rocket relative to the airflow in the rocket body system according to the relative velocity of the rocket body relative to the airflow and a conversion matrix from the launch system to the rocket body;

[0017] Calculating the angle of attack and the sideslip angle according to the components of the velocity of the rocket relative to the airflow in the rocket body system.

[0018] In an implementation, the method of calculating the angle of attack and the sideslip angle according to the components of the velocity of the rocket relative to the airflow in the rocket body system comprises:

[0019] Calculating the angle of attack according to the x-direction and y-direction components of the velocity of the rocket relative to the airflow in the rocket body system;

[0020] Calculating the sideslip angle according to the x-direction, y-direction and z-direction components of the velocity of the rocket relative to the airflow in the rocket body system.

[0021] In an implementation, the method of obtaining the angular acceleration information according to the angular velocity information in the flight telemetry data comprises:

[0022] Filtering the angular velocity information output by the inertial measurement unit in the flight telemetry data by using a preset filter to obtain filtered angular velocity information, wherein the filtered angular velocity information comprises filtered roll angular velocity information, filtered yaw angular velocity information and filtered pitch angular velocity information;

[0023] Deriving the filtered angular velocity information to obtain the angular acceleration information.

[0024] In an implementation, the preset filter comprises a Chebyshev low-pass filter.

[0025] In an implementation, the missile body moment coefficient information includes first moment information, second moment information and third moment information, the first moment information is x-direction moment information, the second moment information is y-direction moment information, the third moment information is z-direction moment information, and the missile body size information includes missile body reference area information and missile body length information.

[0026] The missile body moment coefficient information is calculated according to the missile body resultant moment information, dynamic pressure information and missile body size information.

[0027] The moment components in three directions are obtained according to the missile body resultant moment information.

[0028] The first moment information, the second moment information and the third moment information are calculated according to the moment components in the three directions, the dynamic pressure information, the missile body reference area information and the missile body length information respectively.

[0029] In a second aspect, the application provides a device for identifying aerodynamic parameters of a launch vehicle in a first flight stage, which includes:

[0030] A first calculation unit is configured to calculate an attack angle and a sideslip angle of the launch vehicle in the first flight stage according to measured wind field data and flight telemetry data on the launch day.

[0031] A first acquisition unit is configured to acquire angular acceleration information according to angular velocity information in the flight telemetry data.

[0032] A second calculation unit is configured to calculate missile body resultant moment information according to the angular acceleration information and missile body moment of inertia.

[0033] A third calculation unit is configured to calculate missile body moment coefficient information according to the missile body resultant moment information, dynamic pressure information and missile body size information, wherein the missile body size information includes missile body reference area information and missile body length information.

[0034] A second acquisition unit is configured to perform inverse interpolation operation according to known aerodynamic parameters and the aerodynamic moment coefficients to acquire rudder deflection control quantities, wherein the known aerodynamic parameters include the attack angle, the sideslip angle and Mach number, and the rudder deflection control quantities include pitch rudder deflection control quantity, yaw rudder deflection control quantity and roll rudder deflection control quantity.

[0035] A judgment unit is configured to compare the rudder deflection control quantities with actual rudder deflections during flight to judge the aerodynamic parameters.

[0036] In a third aspect, an electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor is configured to implement the steps of the method for identifying aerodynamic parameters of a first stage of a launch vehicle according to any one of the first aspect when executing the computer program stored in the memory.

[0037] In a fourth aspect, the present application further provides a computer readable storage medium having a computer program stored thereon, and the computer program is executable by a processor to implement the method for identifying aerodynamic parameters of a first stage of a launch vehicle according to any one of the first aspect.

[0038] In summary, the method for identifying aerodynamic parameters of a first stage of a launch vehicle according to the embodiments of the present application includes: calculating the angle of attack and the sideslip angle of the first stage of the launch vehicle according to the measured wind field data and the flight telemetry data on the day of launch; obtaining the angular acceleration information according to the angular velocity information in the flight telemetry data; calculating the moment information of the rocket body according to the angular acceleration information and the moment of inertia of the rocket body; calculating the moment coefficient information of the rocket body according to the moment information of the rocket body, the dynamic pressure information, and the size information of the rocket body, wherein the size information of the rocket body includes the reference area information and the length information of the rocket body; performing reverse interpolation operation according to the known aerodynamic parameters and the aerodynamic moment coefficients to obtain the control amount of the rudder deflection, wherein the known aerodynamic parameters include the angle of attack, the sideslip angle, and the Mach number, and the control amount of the rudder deflection includes the control amount of the pitch rudder deflection, the control amount of the yaw rudder deflection, and the control amount of the roll rudder deflection; and comparing the control amount of the rudder deflection with the actual rudder deflection during the actual flight to judge the aerodynamic parameters. The present disclosure provides a method for identifying aerodynamic parameters of a first stage of a launch vehicle, which calculates the angle of attack and the sideslip angle of the first stage of the launch vehicle according to the measured wind field data and the flight telemetry data on the day of launch; calculates the angular acceleration of the rocket body by filtering and differentiating the angular velocity information of the rocket body output by the inertial measurement unit in the telemetry data; calculates the moment coefficient of the rocket body according to the angular acceleration of the rocket body, the moment of inertia, the dynamic pressure, and the like; and finally performs reverse interpolation according to the known aerodynamic parameters to obtain the identified rudder deflection angle, which is compared with the actual rudder deflection angle transmitted by the telemetry to judge the accuracy of the aerodynamic parameters. For the flight feature points with large deviation, the corresponding aerodynamic parameter points are adjusted and corrected until the identified rudder deflection angle is consistent with the actual rudder deflection angle, and then the accurate aerodynamic parameters are obtained. Finally, the flight stability and reliability of the launch vehicle are improved through iterative design. The method for identifying aerodynamic parameters of a first stage of a launch vehicle according to the present disclosure is simple and easy to implement, and has high engineering application value. The method for identifying aerodynamic parameters of a first stage of a launch vehicle according to the present application, other advantages, objects, and features of the present application will be embodied in part through the following description, and will be understood by those skilled in the art through research and practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0039] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit this specification. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0040] Figure 1 This is a flowchart illustrating a method for identifying aerodynamic parameters during the first stage of a launch vehicle, as provided in an embodiment of this application.

[0041] Figure 2 A structural schematic diagram of an aerodynamic parameter identification device for the first stage of a launch vehicle provided in this application embodiment;

[0042] Figure 3 This is a schematic diagram of an electronic device for identifying aerodynamic parameters during the first stage of a launch vehicle, provided as an embodiment of this application. Detailed Implementation

[0043] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus. The technical solutions of the embodiments of this application will now be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them.

[0044] Please see Figure 1 This is a flowchart illustrating a method for identifying aerodynamic parameters during the first stage of a launch vehicle, provided in an embodiment of this application. Specifically, it may include:

[0045] S110. Based on the measured wind field data and flight telemetry data on the day of launch, calculate the angle of attack and sideslip angle of the rocket's first-stage flight phase.

[0046] For example, the angle of attack (AoA) is the angle between the rocket's forward direction and its axis, which affects the rocket's lift and drag.

[0047] Sideslip Angle is the angle between the rocket body axis in the horizontal plane and its actual flight direction, reflecting the lateral stability of the rocket.

[0048] By calculating these two angles through the measured wind field data and flight telemetry data (including speed and direction) on the launch day, the aerodynamic performance and flight efficiency of the rocket can be evaluated.

[0049] S120, according to the angular velocity information in the flight telemetry data, the angular acceleration information is obtained;

[0050] For example, the angular acceleration information is calculated by the rate of change of the angular velocity information (the rotation speed of the rocket around each axis) in the flight telemetry data. Angular acceleration is the rate of change of angular velocity, which is of great significance to understand the rotation dynamics of the rocket and the response of the control system.

[0051] S130, according to the angular acceleration information and the moment of inertia of the rocket body, the rocket body moment information is calculated;

[0052] For example, the rocket body moment is the product of the distance from the rotation center to the action point of each moment and the force, which reflects the rotation effect of the moment on the rocket body. By using the angular acceleration information and the moment of inertia of the rocket body (the inertia of the object to rotation), the combined moment can be calculated, which is crucial to understand the rotation stability and control efficiency of the rocket.

[0053] S140, according to the rocket body moment information, dynamic pressure information and rocket body size information, the rocket body moment coefficient information is calculated, wherein the rocket body size information includes rocket body reference area information and rocket body length information;

[0054] For example, the moment coefficient is an important aerodynamic parameter, which reflects the normalized value of the moment relative to the dynamic pressure, the reference area and the length of the rocket body. Dynamic pressure is a parameter proportional to the square of the flight speed, and reference area and rocket body length are geometric characteristics of the rocket. By using these information, the moment coefficient can be calculated, so as to better understand the aerodynamic characteristics of the rocket.

[0055] S150, according to the known aerodynamic parameters and the above aerodynamic moment coefficient, inverse interpolation operation is performed to obtain the rudder deflection control quantity, wherein the known aerodynamic parameters include the above angle of attack, the above sideslip angle and the Mach number, and the rudder deflection control quantity includes the pitch rudder deflection control quantity, the yaw rudder deflection control quantity and the roll rudder deflection control quantity;

[0056] For example, by using the known aerodynamic parameters (angle of attack, sideslip angle and Mach number) and the aerodynamic moment coefficient, inverse interpolation operation is performed to obtain the rudder deflection control quantity, including the control quantity of the pitch rudder, the yaw rudder and the roll rudder. Rudder deflection control quantity refers to the angle of rudder surface that needs to be applied in order to achieve the expected flight attitude.

[0057] The specific can be obtained by the following formula:

[0058] Given the angle of attack, sideslip angle, Mach number, according to the known aerodynamic parameters, rudder angle and aerodynamic moment coefficient exists one-to-one mapping relationship, according to the moment coefficient can be inversely interpolated to get the pitch, yaw, roll rudder control quantity:

[0059] δ ′ p = fδ p (Ma, Cm, α, β)

[0060] δ′ y = fδ y (Ma, Cn, α, β)

[0061] δ′ r = fδ r (Ma, Cl, α, β)

[0062] In the formula: δ′ p is the identified pitch rudder control quantity, δ′ y is the identified yaw rudder control quantity, δ′ r is the identified roll rudder control quantity, Cl is the roll moment coefficient, Cn is the yaw moment coefficient, and Cm is the pitch moment coefficient; α is the angle of attack and β is the sideslip angle; Ma is the Mach number, fδ p is the mapping relationship between the pitch rudder control quantity and the related parameters, fδ y is the mapping relationship between the yaw rudder control quantity and the related parameters, and fδ r is the mapping relationship between the roll rudder control quantity and the related parameters.

[0063] S160, based on the above rudder control quantity and the actual flight rudder, to judge the aerodynamic parameters.

[0064] For example, by comparing the actual flight rudder with the calculated rudder control quantity, the accuracy of the aerodynamic parameters and the effectiveness of the control strategy can be evaluated. Through flight test data to identify and correct the rocket aerodynamic parameters, improve the accuracy of the rocket aerodynamic parameters, which is conducive to improving the flight stability and reliability of the launch vehicle.

[0065] In summary, the present disclosure provides a method for identifying aerodynamic parameters of a first stage flight segment of a launch vehicle, which calculates the angle of attack and sideslip angle of the first stage flight segment of the launch vehicle according to the measured wind field data and flight telemetry data on the day of launch; filters the arrow body angular velocity information output by the inertial measurement unit in the telemetry data and then derives the arrow body angular acceleration; calculates the arrow body moment coefficient according to the arrow body angular acceleration, the moment of inertia, and the dynamic pressure; and finally performs inverse interpolation according to the known aerodynamic parameters to obtain the identified rudder deflection angle, which is compared with the actual rudder deflection angle transmitted by the telemetry to judge the accuracy of the aerodynamic parameters, and the corresponding aerodynamic parameter point is adjusted and corrected for the flight feature point with a large deviation, until the identified rudder deflection angle is consistent with the actual rudder deflection angle, so that the accurate aerodynamic parameters are obtained. Finally, the flight stability and reliability of the launch vehicle are improved through iterative design. The method for identifying aerodynamic parameters of a first stage flight segment of a launch vehicle provided by the present disclosure is simple and easy to implement, and has high engineering application value.

[0066] In an available implementation, the method further includes:

[0067] In the case where the rudder deflection control quantity and the actual flight rudder deflection exceed the preset threshold, a moment coefficient correction quantity is determined based on the rudder deflection deviation of the rudder deflection control quantity and the actual flight rudder deflection and the moment coefficient correction coefficient;

[0068] The aerodynamic moment coefficient is corrected based on the moment coefficient correction quantity, so that the rudder deflection deviation of the rudder deflection control quantity and the actual flight rudder deflection is reduced to within the preset threshold.

[0069] For example, the preset threshold is a standard set in advance, which is used to judge whether the deviation between the rudder deflection control quantity and the actual flight rudder deflection is within an acceptable range. If the deviation exceeds the preset threshold, it means that the aerodynamic moment coefficient needs to be adjusted to correct the deviation.

[0070] When it is found that the deviation between the rudder deflection control quantity and the actual flight rudder deflection exceeds the preset threshold, a moment coefficient correction quantity needs to be calculated. The calculation of the correction quantity is based on the rudder deflection deviation, i.e. the difference between the control quantity and the actual value, and the moment coefficient correction coefficient, i.e. an adjustment factor obtained based on experience or test.

[0071] According to the calculated moment coefficient correction quantity, the existing aerodynamic moment coefficient is corrected, the aerodynamic model of the launch vehicle is adjusted, and the aerodynamic model is made more consistent with the actual flight situation, so as to ensure the accuracy of the rudder deflection control quantity.

[0072] Specifically, the correction can be performed by the following formula:

[0073] ΔCm=K p (δ p -δ′ p )

[0074] ACn = K y (δ y - δ' y )

[0075] ACl = K r (δ r - δ' r )

[0076] where: δ p is the actual pitch control amount, δ y is the actual yaw control amount, δ r is the actual roll control amount, K p , K y , K r are the pitch, yaw, and roll moment coefficient correction factors, selected based on experience; and ACm, ACn, ACI are the pitch, yaw, and roll moment coefficient correction amounts.

[0077] The goal of the above correction operation is to reduce the deviation between the control amount and the actual flight control to within a preset threshold. This process may need to be iterated, with continuous adjustment and comparison until the target deviation range is reached, ensuring the stability and accuracy of the rocket flight. By identifying and correcting the rocket aerodynamic parameters through flight test data, the accuracy of the rocket aerodynamic parameters is improved, which is beneficial to improving the flight stability and reliability of the launch vehicle

[0078] In one possible implementation, the above calculation of the attack angle and the sideslip angle of the rocket first flight stage according to the measured wind field data and flight telemetry data on the launch day includes:

[0079] According to the above measured wind field data and flight telemetry data on the launch day, the relative speed of the rocket body relative to the airflow is calculated;

[0080] According to the above relative speed of the rocket body relative to the airflow and the conversion matrix from the launch system to the rocket body, the components of the rocket relative airflow speed in the rocket system are determined;

[0081] According to the above components of the rocket relative airflow speed in the rocket system, the above attack angle and sideslip angle are calculated.

[0082] For example, first, the measured wind field data on the launch day is needed, which provides the wind speed and direction information in the rocket launch environment. At the same time, the flight telemetry data can be used to obtain the real-time position, speed, and other information of the rocket.

[0083] The relative speed of the rocket body relative to the airflow is calculated by the vector difference between the actual moving speed of the rocket and the surrounding wind speed. This relative speed is the basis for further analysis, as it directly affects the aerodynamic force faced by the rocket.

[0084] The motion of the rocket can be described in different reference frames. The launch frame is usually a fixed reference frame with the ground as the reference, while the rocket frame is a reference frame that moves with the rocket itself. By a transformation matrix from the launch frame to the rocket frame, the velocity of the rocket relative to the ground can be converted to its components in the rocket frame.

[0085] Finally, the attack angle and the sideslip angle of the rocket can be calculated using the components of the velocity of the rocket relative to the airflow in the rocket frame obtained by the above steps.

[0086] It should be noted that the relative velocity of the rocket body relative to the airflow can be calculated by the following formula:

[0087] V xd = V fs + v_wind

[0088]

[0089] wherein V fs is the velocity vector of the rocket body in the launch frame, is the transformation matrix from the launch frame to the rocket frame, and v_wind is the wind velocity vector in the launch frame.

[0090] In an embodiment, the attack angle and the sideslip angle are calculated according to the components of the velocity of the rocket relative to the airflow in the rocket frame, comprising:

[0091] the attack angle is calculated according to the x-direction and y-direction components of the velocity of the rocket relative to the airflow in the rocket frame;

[0092] the sideslip angle is calculated according to the x-direction, y-direction and z-direction components of the velocity of the rocket relative to the airflow in the rocket frame.

[0093] For example, the rocket frame is usually defined as: the x-axis points to the forward direction of the rocket, the y-axis is usually horizontal and perpendicular to the x-axis, pointing to the right side of the rocket, and the z-axis is perpendicular to the x-y plane, usually pointing upward.

[0094] The attack angle a and the sideslip angle b of the rocket in the first stage flight can be calculated by the following formula:

[0095] a = -arctan(v bxdy / v bxdx )

[0096]

[0097] V bxd is the component of the velocity of the rocket relative to the airflow in the rocket frame

[0098] In one possible implementation, the angular acceleration information is obtained from the angular velocity information in the flight telemetry data, including:

[0099] The angular velocity information output by the inertial measurement unit (IMU) or "inertial measurement unit" (IMU) is filtered using a preset filter to obtain filtered angular velocity information, wherein the filtered angular velocity information includes filtered roll angular velocity information, filtered yaw angular velocity information and filtered pitch angular velocity information.

[0100] The filtered angular velocity information is differentiated to obtain angular acceleration information.

[0101] For example, the purpose of filtering is to remove noise from the angular velocity information output by the inertial measurement unit (IMU) or "inertial measurement unit" (IMU) to obtain smoother and more reliable data. In actual flight, due to various environmental factors and characteristics of the device itself, the original telemetry data often contains a certain amount of noise.

[0102] The preset filter can be any effective digital or analog filter, such as a low-pass filter, a Kalman filter, etc., for filtering out high-frequency noise and retaining useful signals.

[0103] The filtered angular velocity information includes three main axes of rotation: roll, yaw and pitch. The angular velocity of each axis describes the rotation speed of the rocket around that axis and is a key data for rocket attitude analysis.

[0104] The differentiation operation refers to calculating the rate of change of the filtered angular velocity with respect to time, i.e. angular acceleration. Angular acceleration is a physical quantity that describes the dynamic change of the rocket's rotation, which indicates how the rotation speed of the rocket on each rotation axis accelerates or decelerates over time. Angular acceleration information, including roll angular acceleration, yaw angular acceleration and pitch angular acceleration, provides real-time feedback for the rocket control system, helping to optimize the flight attitude and trajectory of the rocket.

[0105] Specifically, the filtered angular velocity is differentiated to obtain angular acceleration;

[0106] ω lb =G lb ·ω

[0107]

[0108] In the formula: ω is the angular velocity output by the inertial measurement unit (IMU) or "inertial measurement unit" (IMU), G lb is a low-pass filter, ω lb is the filtered angular velocity, and ΔT is the time interval between adjacent two data.

[0109] In an embodiment, the preset filter is a Chebyshev low-pass filter.

[0110] Chebyshev filters, for example, place particular emphasis on the transition characteristics between the passband and the stopband, allowing a certain amount of ripple in the passband or the stopband to achieve a steeper transition slope. This characteristic makes Chebyshev filters particularly effective at filtering out high-frequency noise while preserving the main portion of the signal.

[0111] A low-pass filter is a filter that allows signals below a certain cutoff frequency to pass through while blocking signals above this frequency. In processing angular velocity signals, a low-pass filter can effectively remove noise components caused by vibrations, electrical noise, or other high-frequency disturbances.

[0112] In the processing of rocket flight telemetry data, using a Chebyshev low-pass filter can optimize the quality of the angular velocity signal. By setting an appropriate cutoff frequency, the Chebyshev filter can effectively filter out unwanted high-frequency noise while preserving as much important information as possible about the rocket's rotational dynamics. The processed angular velocity information, i.e., the filtered roll angular velocity, yaw angular velocity, and pitch angular velocity, will be smoother and more accurate, providing a more reliable basis for calculating angular acceleration.

[0113] In an embodiment, the rocket body moment coefficient information includes first moment information, second moment information, and third moment information, the first moment information is x-direction moment information, the second moment information is y-direction moment information, and the third moment information is z-direction moment information, and the rocket body size information includes:

[0114] The rocket body moment coefficient information is calculated based on the rocket body combined moment information, dynamic pressure information, and rocket body size information, including:

[0115] The moment components in three directions according to the rocket body combined moment information;

[0116] The first moment information, the second moment information, and the third moment information are calculated based on the moment components in the three directions, the dynamic pressure information, the rocket body reference area information, and the rocket body length information, respectively.

[0117] For example, first, the components of the rocket body combined moment information in three directions need to be determined. This includes the moment components around the x, y, and z axes, corresponding to the rocket's tendency to rotate around these three axes, respectively.

[0118] Dynamic pressure is generated due to the movement of the rocket relative to the airflow, and its value depends on the square of the rocket's speed and the air density. Rocket reference area generally refers to the cross-sectional area of the rocket, while rocket length is the length dimension of the rocket. These two parameters are the basic reference quantities for calculating the moment coefficient.

[0119] For each direction (x, y, z), the moment coefficient is calculated according to the moment component in the corresponding direction, the dynamic pressure, the reference area of the arrow body, and the length of the arrow body. In this way, a first moment coefficient (x direction, which may represent a pitch moment coefficient), a second moment coefficient (y direction, which may represent a yaw moment coefficient), and a third moment coefficient (z direction, which may represent a roll moment coefficient) can be obtained.

[0120] Specifically, the first moment coefficient, the second moment coefficient, and the third moment coefficient can be determined by the following formula:

[0121] According to the angular acceleration of the arrow body and the moment of inertia, the resultant moment of the arrow body is calculated:

[0122]

[0123] In the formula, J is the moment of inertia of the arrow body. The moment coefficient of the arrow body is calculated by the moment acting on the arrow body:

[0124]

[0125] Wherein, q is the dynamic pressure, s is the reference area of the arrow body, l is the length of the arrow body, Cl is the roll moment coefficient, Cn is the yaw moment coefficient, and Cm is the pitch moment coefficient.

[0126] Referring to Figure 2 The device for identifying aerodynamic parameters of a first flight stage of a launch vehicle provided in the embodiments of the present application can include:

[0127] The first calculation unit 21 is configured to calculate the angle of attack and the sideslip angle of the first flight stage of the launch vehicle according to the measured wind field data and the flight telemetry data on the launch day.

[0128] The first acquisition unit 22 is configured to acquire angular acceleration information according to the angular velocity information in the flight telemetry data.

[0129] The second calculation unit 23 is configured to calculate arrow body resultant moment information according to the angular acceleration information and the moment of inertia of the arrow body.

[0130] The third calculation unit 24 is configured to calculate arrow body moment coefficient information according to the arrow body resultant moment information, dynamic pressure information, and arrow body size information, wherein the arrow body size information includes arrow body reference area information and arrow body length information.

[0131] The second acquisition unit 25 is configured to perform inverse interpolation operation on the known aerodynamic parameters and the aerodynamic moment coefficients to obtain rudder deflection control amounts, wherein the known aerodynamic parameters include the angle of attack, the sideslip angle, and the Mach number, and the rudder deflection control amounts include pitch rudder deflection control amounts, yaw rudder deflection control amounts, and roll rudder deflection control amounts.

[0132] The judging unit 26 is configured to compare the rudder deflection control amount with the actual rudder deflection during flight to judge the aerodynamic parameter.

[0133] As shown in the method for identifying aerodynamic parameters of a first flight stage of a launch vehicle according to the embodiment of the present application, the method comprises the following steps of: Figure 3 The electronic device 300 according to the embodiment of the present application comprises a memory 310, a processor 320, and a computer program 311 stored in the memory 310 and executable on the processor. When the processor 320 executes the computer program 311, the steps of any method for identifying aerodynamic parameters of a first flight stage of a launch vehicle according to the embodiment of the present application are implemented.

[0134] The electronic device according to the embodiment of the present application is the device used to implement the method for identifying aerodynamic parameters of a first flight stage of a launch vehicle according to the embodiment of the present application. Therefore, based on the method according to the embodiment of the present application, those skilled in the art can understand the specific implementation of the electronic device according to the embodiment of the present application and various changes thereof. Therefore, how the electronic device according to the embodiment of the present application implements the method according to the embodiment of the present application is not described in detail herein. The device used to implement the method according to the embodiment of the present application belongs to the scope of protection of the present application.

[0135] In the specific implementation process, the computer program 311 can implement any embodiment of the method according to the embodiment of the present application when executed by the processor. Figure 1

[0136] It should be noted that in the above embodiments, the description of each embodiment has its own emphasis, and the parts not described in detail in an embodiment can be referred to the related description of other embodiments.

[0137] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can be in the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can be in the form of a computer program product implemented on one or more computer usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer usable program code.

[0138] The present application is described with reference to flowcharts and / or block diagrams according to the method, device (system), and computer program product of the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded computer, or other programmable data processing devices to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices produce a machine that implements the flowcharts and / or block diagrams. Figure 1 ​one or more processes and / or blocks Figure 1 an apparatus for performing the functions specified in the flowchart or multiple flows and / or blocks.

[0139] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions apparatus implementing the flowchart Figure 1 one or more processes and / or blocks Figure 1 an apparatus for performing the functions specified in the flowchart or multiple flows and / or blocks.

[0140] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process so that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the flowchart Figure 1 one or more processes and / or blocks Figure 1 an apparatus for performing the functions specified in the flowchart or multiple flows and / or blocks.

[0141] The embodiments of the present application also provide a computer program product, which includes computer software instructions, when the computer software instructions are run on a processing device, cause the processing device to execute the flowchart of the launch vehicle first stage flight aerodynamic parameter identification in the corresponding embodiments.

[0142] The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the flowchart or function according to the embodiments of the present application is produced. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions can be transmitted from one website site, computer, server or data center to another website site, computer, server or data center through wired (such as coaxial cable, optical fiber, digital subscriber line (digital subscriber line, DSL)) or wireless (such as infrared, wireless, microwave, etc.) way. The computer-readable storage medium can be any available medium that the computer can store or be integrated into a server, data center and other data storage devices containing one or more available media sets. The available media can be magnetic media (for example, floppy disk, hard disk, magnetic tape), optical media (for example, DVD), or semiconductor media (for example, solid state disk (solid state disk, SSD)) and the like.

[0143] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the system, device and unit described above can refer to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0144] In several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of units is only a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some interface, device or unit, and can be electrical, mechanical or other forms.

[0145] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, that is, they can be located in one place, or can be distributed on a plurality of network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment scheme.

[0146] In addition, the functional units in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0147] If the integrated unit is realized in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application essentially or the part of the prior art that makes a contribution or the whole or part of the technical solutions can be embodied in the form of a software product, which is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the embodiments of the method of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various program code storage media.

[0148] The above, the above examples are only used to illustrate the technical solutions of the present application, but not limit them; although the present application is described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions recorded in the foregoing examples can still be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for identifying aerodynamic parameters of a first stage flight segment of a launch vehicle, characterized in that, The method comprises the following steps: According to the measured wind field data and flight telemetry data on the day of launch, the attack angle and sideslip angle of the first stage of the rocket are calculated; According to the angular velocity information in the flight telemetry data, the angular acceleration information is obtained; According to the angular acceleration information and the moment of inertia of the rocket body, the combined moment information of the rocket body is calculated; According to the combined moment information of the rocket body, the dynamic pressure information and the size information of the rocket body, the moment coefficient information of the rocket body is calculated, wherein the size information of the rocket body includes the reference area information and the length information of the rocket body; According to the known aerodynamic parameters and the aerodynamic moment coefficient, the reverse interpolation operation is performed to obtain the rudder deflection control quantity, wherein the known aerodynamic parameters include the attack angle, the sideslip angle and the Mach number, and the rudder deflection control quantity includes the pitch rudder deflection control quantity, the yaw rudder deflection control quantity and the roll rudder deflection control quantity; Based on the comparison between the rudder deflection control quantity and the actual flight rudder deflection, the aerodynamic parameters are judged.

2. The method according to claim 1, wherein, Further comprising: In the case that the rudder deflection control quantity and the actual flight rudder deflection exceed the preset threshold, the moment coefficient correction quantity is determined based on the rudder deflection difference between the rudder deflection control quantity and the actual flight rudder deflection and the moment coefficient correction coefficient; Based on the moment coefficient correction quantity, the aerodynamic moment coefficient is corrected to reduce the rudder deflection difference between the rudder deflection control quantity and the actual flight rudder deflection to within the preset threshold.

3. The first stage flight aerodynamic parameter identification method of the launch vehicle according to claim 1, wherein According to the measured wind field data and flight telemetry data on the day of launch, the attack angle and sideslip angle of the first stage of the rocket are calculated, comprising: According to the measured wind field data and flight telemetry data on the day of launch, the relative velocity of the rocket body relative to the airflow is calculated; According to the relative velocity of the rocket body relative to the airflow and the conversion matrix from the launch system to the rocket body, the components of the velocity of the rocket relative to the airflow in the rocket system are determined; According to the components of the velocity of the rocket relative to the airflow in the rocket system, the attack angle and the sideslip angle are calculated.

4. The method according to claim 3, wherein, According to the components of the velocity of the rocket relative to the airflow in the rocket system, the attack angle and the sideslip angle are calculated, comprising: According to the x-direction and y-direction components of the velocity of the rocket relative to the airflow in the rocket system, the attack angle is calculated; According to the x-direction, y-direction and z-direction components of the velocity of the rocket relative to the airflow in the rocket system, the sideslip angle is calculated.

5. The method according to claim 1, wherein, According to the angular velocity information output by the inertial measurement unit in the flight telemetry data, the angular acceleration information is obtained, comprising: The angular velocity information output by the inertial measurement unit in the flight telemetry data is filtered by using a preset filter to obtain filtered angular velocity information, wherein the filtered angular velocity information includes filtered roll angular velocity information, filtered yaw angular velocity information and filtered pitch angular velocity information; The filtered angular velocity information is differentiated to obtain the angular acceleration information.

6. The method according to claim 5, wherein, The preset filter includes a Chebyshev low-pass filter.

7. The method according to claim 1, wherein, The moment coefficient information of the rocket body includes first moment information, second moment information and third moment information, the first moment information is x-direction moment information, the second moment information is y-direction moment information, and the third moment information is z-direction moment information; The calculating the missile body moment coefficient information according to the missile body resultant moment information, dynamic pressure information and missile body size information comprises: calculating moment components in three directions according to the missile body resultant moment information; calculating the first moment information, the second moment information and the third moment information according to the moment components in the three directions, the dynamic pressure information, the missile body reference area information and the missile body length information respectively.

8. A device for identifying aerodynamic parameters of a first stage flight section of a carrier rocket, characterized in that comprise: The first calculation unit is used for calculating the attack angle and the sideslip angle of the first stage of the rocket according to the measured wind field data and the flight telemetry data on the launch day; The first acquisition unit is used for acquiring the angular acceleration information according to the angular velocity information in the flight telemetry data; The second calculation unit is used for calculating the missile body resultant moment information according to the angular acceleration information and the missile body moment of inertia; The third calculation unit is used for calculating the missile body moment coefficient information according to the missile body resultant moment information, dynamic pressure information and missile body size information, wherein the missile body size information comprises missile body reference area information and missile body length information; The second acquisition unit is used for performing reverse interpolation operation according to known aerodynamic parameters and aerodynamic moment coefficients to acquire the rudder deflection control quantity, wherein the known aerodynamic parameters comprise the attack angle, the sideslip angle and the Mach number, and the rudder deflection control quantity comprises the pitch rudder deflection control quantity, the yaw rudder deflection control quantity and the roll rudder deflection control quantity; The evaluation unit is used for comparing the rudder deflection control quantity with the actual rudder deflection during flight to evaluate the aerodynamic parameters.

9. An electronic device comprising: The memory and the processor are characterized in that the processor is used to implement the steps of the launch vehicle first stage flight aerodynamic parameter identification method of any one of claims 1-7 when executing the computer program stored in the memory.

10. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the launch vehicle first stage flight aerodynamic parameter identification method of any one of claims 1-7.

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