An aircraft full-scale static test attitude adjustment method

Abstract

This application belongs to the technical field of full-aircraft static test, and specifically relates to a method for adjusting the attitude of a full-aircraft static test. It is designed to measure and sense the aircraft attitude based on the calculation of the center of gravity of the inertial test load. When it is judged that the change in the aircraft attitude exceeds the limit, the adjustment amount at the aircraft restraint point is calculated and adjusted by an actuator, so as to accurately obtain the true and complete attitude of the aircraft during the test. The adjustment amount is calculated theoretically according to the measured attitude, which can achieve automatic closed-loop control during the test, and can adjust and control the aircraft attitude with high precision and high efficiency during the test, improve the test loading accuracy, and realize the accurate assessment and verification of the structural strength.

Description

Technical Field

[0001] This application belongs to the technical field of aircraft full-scale static test, and particularly relates to a method for adjusting the attitude of aircraft full-scale static test. Background Art

[0002] The goal of aircraft full-scale static test is to simulate the loading of the structure under various extreme conditions that may occur during the service of the aircraft in a laboratory environment, and to verify whether the structure meets the strength requirements specified by the standards.

[0003] During aircraft full-scale static test, the aircraft needs to be adjusted to a set attitude, constrained at the constraint points, and the test load is applied based on the set attitude. However, during the test, due to factors such as deformation coordination and engineering errors, the attitude of the aircraft will change, causing the direction of the loading point to change and affecting the loading accuracy of the test load.

[0004] Currently, in aircraft full-scale static test, there is a lack of accurate means for perceiving the attitude of the aircraft and its adjustment method, making it difficult to ensure the accurate loading of the test load.

[0005] In view of the existence of the above technical defects, this application is proposed.

[0006] It should be noted that the disclosure of the above background art content is only for assisting in understanding the inventive concept and technical solution of this application, and it does not necessarily belong to the prior art of this patent application. Without clear evidence indicating that the above content was publicly available on the filing date of this application, the above background art should not be used to evaluate the novelty and inventiveness of this application. Summary of the Invention

[0007] The purpose of this application is to provide a method for adjusting the attitude of aircraft full-scale static test to overcome or mitigate at least one aspect of the known technical defects.

[0008] The technical solution of this application is as follows:

[0009] A method for adjusting the attitude of aircraft full-scale static test includes:

[0010] Step 1. Calculate the center of gravity of the inertial test load:

[0011] Separate the aerodynamic test load and the inertial test load in the test load, and calculate the center of gravity x g , z g , y g of the inertial test load, where x g is the coordinate of the center of gravity of the inertial test load in the longitudinal direction of the aircraft; z g is the coordinate of the center of gravity of the inertial test load in the lateral direction of the aircraft; y g is the coordinate of the center of gravity of the inertial test load in the vertical direction of the aircraft;

[0012] Step 2. Measure and sense the aircraft attitude:

[0013] Displacement measurement points are arranged on the structure with high stiffness near the center of gravity of the inertial test load. Based on the displacements of the displacement measurement points, the aircraft attitude is calculated; or,

[0014] An attitude sensing gyroscope is installed at or near the center of gravity of the inertial test load to measure the aircraft attitude; or,

[0015] An attitude coordinate system parallel to the three axes of the whole-aircraft coordinate system is established with the center of gravity of the inertial test load as the origin. Based on the structural displacement response, the whole-aircraft model is reconstructed in the whole-aircraft coordinate system. By comparing with the set whole-aircraft model, the conversion relationship of the attitude coordinate system in the reconstructed whole-aircraft model and the set whole-aircraft model is obtained, and the aircraft attitude is derived;

[0016] Step 3. Aircraft attitude analysis:

[0017] Judge whether the change in the aircraft attitude exceeds the limit. If so, adjust the aircraft attitude;

[0018] Step 4. Aircraft attitude adjustment:

[0019] Calculate the adjustment amount at the aircraft constraint points and adjust with actuators:

[0020] Adjustment amount of the aircraft constraint point in the course direction

[0021] Adjustment amount of the aircraft constraint point in the vertical direction △y = △Y + y m -yθ1 - y γ1 ;

[0022] Adjustment amount of the aircraft constraint point in the lateral direction

[0023] Wherein,

[0024] x θ1 = x z +(x m -x z )cosθ - (y m -y z )sinθ, y θ1 = y z +(y m -y z )cosθ + (x m -x z )sinθ;

[0025] y γ1 = y z +(y m -y z )cosγ - (zm -z z )sinγ, z γ1 =z z +(z m -z z )cosγ+(y m -y z )sinγ;

[0026]

[0027] x m is the coordinate of the aircraft constraint point in the flight direction, and △X is the translation amount of the aircraft attitude change center of gravity in the flight direction;

[0028] y m is the coordinate of the aircraft constraint point in the vertical direction, and △Y is the translation amount of the aircraft attitude change center of gravity in the vertical direction;

[0029] z m is the coordinate of the aircraft constraint point in the lateral direction, and △Z is the translation amount of the aircraft attitude change center of gravity in the lateral direction;

[0030] θ is the pitch angle of the aircraft;

[0031] is the yaw angle of the aircraft;

[0032] γ is the roll angle of the aircraft.

[0033] According to at least one embodiment of the present application, in the above aircraft full-scale static test attitude adjustment method, in step one, the coordinate of the inertial test load center of gravity in the flight direction of the aircraft

[0034] The coordinate of the inertial test load center of gravity in the vertical direction of the aircraft y g , take the coordinate of the aircraft design center of gravity in the vertical direction;

[0035] The coordinate of the inertial test load center of gravity in the lateral direction of the aircraft

[0036] wherein,

[0037] n is the number of node inertial test loads;

[0038] F yi is the i-th node inertial test load;

[0039] x i is the coordinate of the i-th node inertial test load in the flight direction of the aircraft;

[0040] z i is the coordinate of the i-th node inertial test load in the lateral direction of the aircraft.

[0041] According to at least one embodiment of the present application, in the above aircraft full-aircraft static test attitude adjustment method, in step two, displacement measurement points are arranged on the structure with relatively large stiffness near the center of gravity of the inertial test load, and the aircraft attitude is calculated based on the displacements of the displacement measurement points. Specifically:

[0042] Arrange 4 displacement measurement points on the structure with relatively large stiffness near the center of gravity of the inertial test load;

[0043] Calculate the actual rigid body displacements of the 4 displacement measurement points as the measured displacements:

[0044] The actual displacement Δx of the i-th displacement measurement point in the aircraft's flight direction i = Δx ic - Δx is ;

[0045] The actual displacement Δy of the i-th displacement measurement point in the vertical direction of the aircraft i = Δy ic - Δy is ;

[0046] The actual displacement Δz of the i-th displacement measurement point in the lateral direction of the aircraft i = Δz ic - Δz is ;

[0047] Wherein,

[0048] Δx ic is the measured displacement of the i-th displacement measurement point in the flight direction of the aircraft; Δx is is the elastic displacement calculated by finite element of the i-th displacement measurement point in the flight direction of the aircraft;

[0049] Δy ic is the measured displacement of the i-th displacement measurement point in the vertical direction of the aircraft; Δy is is the elastic displacement calculated by finite element of the i-th displacement measurement point in the vertical direction of the aircraft;

[0050] Δz ic is the measured displacement of the i-th displacement measurement point in the lateral direction of the aircraft; Δz is is the elastic displacement calculated by finite element of the i-th displacement measurement point in the lateral direction of the aircraft;

[0051] Calculate the center of gravity translation amount of the aircraft attitude change:

[0052] The translation amount of the center of gravity of the aircraft attitude change in the flight direction

[0053] The translation amount of the center of gravity of the aircraft attitude change in the vertical direction

[0054] The translation amount of the center of gravity of the aircraft attitude change in the lateral direction

[0055] Calculate the pitch angle, roll angle, and yaw angle of the aircraft to obtain the aircraft attitude:

[0056] Aircraft pitch angle

[0057] Aircraft roll angle

[0058] Aircraft yaw angle

[0059] According to at least one embodiment of the present application, in step three of the above aircraft full-scale static test attitude adjustment method, if it is determined that the translation amount of the center of gravity of the aircraft attitude change in the heading, vertical, and lateral directions exceeds 3 mm, or the pitch angle, roll angle, and yaw angle are greater than 1°, then the aircraft attitude is adjusted.

[0060] The present application has at least the following beneficial technical effects:

[0061] Provide an aircraft full-scale static test attitude adjustment method. Designed based on calculating the center of gravity of the inertial test load, measure and sense the aircraft attitude. When it is judged that the aircraft attitude change exceeds the limit, calculate the adjustment amount at the aircraft constraint point and adjust it with an actuator. The true and complete attitude of the aircraft during the test can be accurately obtained. The adjustment amount is calculated theoretically based on the measured attitude, and automatic closed-loop control can be realized during the test. It can adjust and control the aircraft attitude with high precision and high efficiency during the test, improve the test loading accuracy, and realize the accurate assessment and verification of the structural strength. Description of the Drawings

[0062] Figure 1 is a schematic diagram of the aircraft full-scale static test attitude adjustment method provided by the embodiment of the present application;

[0063] Figure 2 is a schematic diagram of the aircraft full-scale coordinate system provided by the embodiment of the present application;

[0064] Figure 3 is a schematic diagram of the distribution of displacement measurements on the aircraft provided by the embodiment of the present application.

[0065] To better illustrate this embodiment, some components in the drawings are omitted, enlarged, or reduced, which do not represent the dimensions of the actual product. In addition, the drawings are only for illustrative purposes and cannot be construed as a limitation of this patent. Detailed Embodiments

[0066] To make the technical solutions and their advantages of this application clearer, the following will further describe the technical solutions of this application clearly and completely in conjunction with the accompanying drawings. It can be understood that the specific embodiments described herein are only partial embodiments of this application, which are only used to explain this application rather than limit this application. It should be noted that for the convenience of description, only the parts related to this application are shown in the drawings, and other related parts can refer to the general design. Without conflict, the embodiments in this application and the technical features in the embodiments can be combined with each other to obtain new embodiments.

[0067] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of this application should be the ordinary meanings understood by those of ordinary skill in the art to which this application belongs. The words indicating directions such as "upper", "lower", "left", "right", "center", "vertical", "horizontal", "inner", "outer", etc. used in the description of this application are only used to indicate relative directions or position relationships, rather than implying that the device or component must have a specific orientation, be constructed and operated in a specific orientation. When the absolute position of the object being described changes, its relative position relationship may also change accordingly. Therefore, it cannot be understood as a limitation to this application. The terms "first", "second", "third", and similar terms used in the description of this application are only for descriptive purposes to distinguish different components, and cannot be understood as indicating or implying relative importance. The similar words such as "a", "one", or "the" used in the description of this application should not be understood as an absolute limitation on the quantity, but should be understood as having at least one. The similar words such as "including" or "comprising" used in the description of this application are intended to mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects.

[0068] In addition, it should also be noted that unless otherwise clearly specified and limited, the similar words such as "installed", "connected", "joined" used in the description of this application should be understood in a broad sense. For example, the connection can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and can also be the communication inside two components. Those skilled in the art can understand its specific meaning in this application according to the specific situation.

[0069] The following will further describe in detail the aircraft full-scale static test attitude adjustment method provided by this application in conjunction with the attached Figures 1 to 3 aircraft full-scale static test attitude adjustment method provided by this application.

[0070] The aircraft full-scale static test attitude adjustment method, for the specific process, see Figure 1 .

[0071] Step 1: Calculate the center of gravity of the inertial test load:

[0072] Separate the aerodynamic test load and the inertial test load in the test load, and calculate the center of gravity x of the inertial test load g , z g , y g , where x g is the coordinate of the center of gravity of the inertial test load in the aircraft's flight direction; z g is the coordinate of the center of gravity of the inertial test load in the lateral direction of the aircraft; y g is the coordinate of the center of gravity of the inertial test load in the vertical direction of the aircraft, and take the coordinate of the aircraft design center of gravity in the vertical direction.

[0073]

[0074]

[0075] Among them,

[0076] n is the number of node inertial test loads;

[0077] F yi is the inertial test load of the i-th node;

[0078] x i is the coordinate of the inertial test load of the i-th node in the flight direction of the aircraft;

[0079] z i is the coordinate of the inertial test load of the i-th node in the lateral direction of the aircraft.

[0080] Step 2. Measure and sense the aircraft attitude:

[0081] Arrange displacement measurement points on the structure with relatively high stiffness near the center of gravity of the inertial test load, and calculate the aircraft attitude based on the displacements of the displacement measurement points; or,

[0082] Install an attitude sensing gyroscope at or near the center of gravity of the inertial test load to measure the aircraft attitude; or,

[0083] Establish an attitude coordinate system parallel to the three axes of the whole aircraft coordinate system with the center of gravity of the inertial test load as the origin, reconstruct the whole aircraft model based on the structural displacement response in the whole aircraft coordinate system, compare it with the set whole aircraft model, obtain the conversion relationship of the attitude coordinate system in the reconstructed whole aircraft model and the set whole aircraft model, and obtain the aircraft attitude.

[0084] Step 3. Aircraft attitude analysis:

[0085] Judge whether the change in the aircraft attitude exceeds the limit, and if so, perform aircraft attitude adjustment.

[0086] Step 4. Aircraft attitude adjustment:

[0087] Calculate the adjustment amount at the aircraft constraint point and adjust it with the actuator:

[0088] Adjustment amount of the aircraft constraint point in the course direction

[0089] Adjustment amount of the aircraft constraint point in the vertical direction △y = △Y + y m -yθ1 - y γ1 ;

[0090] Adjustment amount of the aircraft constraint point in the lateral direction

[0091] Among them,

[0092] x θ1 = x z +(x m - x z )cosθ - (y m - y z )sinθ, y θ1 = y z +(y m - y z )cosθ+(x m - x z )sinθ;

[0093] y γ1 = y z +(y m - y z )cosγ - (z m - z z )sinγ, z γ1 = z z +(z m - z z )cosγ+(y m - y z )sinγ;

[0094]

[0095] x m is the coordinate of the aircraft constraint point in the course direction, and △X is the translation amount of the aircraft attitude change center of gravity in the course direction;

[0096] y m is the coordinate of the aircraft constraint point in the vertical direction, and △Y is the translation amount of the aircraft attitude change center of gravity in the vertical direction;

[0097] z m is the coordinate of the aircraft constraint point in the lateral direction, and △Z is the translation amount of the aircraft attitude change center of gravity in the lateral direction;

[0098] θ, γ are the pitch angle, yaw angle, and roll angle of the aircraft respectively, and all attitude angles are positive in the counterclockwise direction.

[0099] In a specific embodiment, the initial pitch angle, yaw angle, and roll angle of the aircraft are zero. The vertical displacement of the nose landing gear of the aircraft is restricted, the vertical displacement and heading displacement of the left and right main landing gears are restricted, and the lateral displacement of the right main landing gear is restricted to achieve six-degree-of-freedom statically determinate constraints. The vertical displacement mainly causes the effects of vertical translation, roll, and pitch; the lateral displacement mainly causes lateral translation, yaw, and roll; the heading displacement mainly causes heading translation, pitch, and yaw. The test load is the 2.5g condition. The aircraft global coordinate system is constructed, with the X direction of the aircraft against the heading, the Y direction vertically upward, and the Z direction pointing to the left wing tip, as Figure 2 shown.

[0100] The aircraft global static test attitude adjustment method disclosed in the above embodiment is implemented as follows:

[0101] Step 1: Calculate the center of gravity x g , y g , z g .

[0102] Step 2: Measure and sense the aircraft attitude:

[0103] At the structure with relatively large stiffness near the center of gravity x g , y g , z g of the inertial test load, arrange 4 displacement measurement points. Based on the displacements of the displacement measurement points, calculate the aircraft attitude, as Figure 3 shown.

[0104] Considering the elastic deformation of the aircraft structure, the actual rigid body displacement of the 4 displacement measurement points is the difference between the measured displacement and the elastic displacement, that is:

[0105] The actual displacement Δx i of the i-th displacement measurement point in the aircraft heading direction = Δx ic -Δx is ;

[0106] The actual displacement Δy i of the i-th displacement measurement point in the aircraft vertical direction = Δy ic -Δy is ;

[0107] The actual displacement Δz i of the i-th displacement measurement point in the aircraft lateral direction = Δz ic -Δz is ;

[0108] Among them,

[0109] Δxic The measured displacement of the i-th displacement measurement point in the flight direction of the aircraft; Δx is The elastic displacement calculated by finite element of the i-th displacement measurement point in the flight direction of the aircraft, which can be ignored;

[0110] Δy ic The measured displacement of the i-th displacement measurement point in the vertical direction of the aircraft; Δy is The elastic displacement calculated by finite element of the i-th displacement measurement point in the vertical direction of the aircraft, which can be ignored;

[0111] Δz ic The measured displacement of the i-th displacement measurement point in the lateral direction of the aircraft; Δz is The elastic displacement calculated by finite element of the i-th displacement measurement point in the lateral direction of the aircraft, which can be ignored;

[0112] The translation amount of the center of gravity in the flight direction due to the change of the aircraft attitude

[0113] The translation amount of the center of gravity in the vertical direction due to the change of the aircraft attitude

[0114] The translation amount of the center of gravity in the lateral direction due to the change of the aircraft attitude

[0115] The pitch angle of the aircraft

[0116] The roll angle of the aircraft

[0117] The yaw angle of the aircraft

[0118] Step 3. Aircraft attitude analysis:

[0119] If the translation amounts of the center of gravity of the aircraft attitude change in the flight direction, vertical direction, and lateral direction are all within 3 mm, and the pitch angle, roll angle, and yaw angle are less than 1°, continue the test; otherwise, adjust the aircraft attitude. During the test, the aircraft does not need to be adjusted in attitude before the test load reaches 40%, and after the test load reaches 40%, the aircraft attitude needs to be gradually adjusted.

[0120] Step 4. Aircraft attitude adjustment.

[0121] Taking the right main landing gear restraint point as an example, calculate the displacement adjustment amount as follows:

[0122] The adjustment amount in the flight direction

[0123] The adjustment amount in the vertical direction △y = △Y + y m -yθ1 - y γ1 ;

[0124] Lateral adjustment amount

[0125] The aircraft full-aircraft static test attitude adjustment method disclosed in the above embodiments is designed to measure and sense the aircraft attitude on the basis of calculating the center of gravity of the inertial test load. When it is judged that the change in the aircraft attitude exceeds the limit, the adjustment amount at the aircraft restraint point is calculated and adjusted by the actuator, so that the true and complete attitude of the aircraft in the test can be accurately obtained. The adjustment amount is calculated according to the measured attitude theory, and automatic closed-loop control can be realized in the test, and the aircraft attitude can be adjusted and controlled with high precision and high efficiency in the test, the test loading accuracy can be improved, and the accurate assessment and verification of the structural strength can be realized.

[0126] So far, the technical solutions of the present application have been described in conjunction with the preferred embodiments shown in the drawings. Those skilled in the art should understand that the protection scope of the present application is obviously not limited to these specific embodiments. Without departing from the principle of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present application.

Claims

1. An aircraft full-scale static test attitude adjustment method, characterized in that Including: Step 1: Calculate the center of gravity of the inertial test load: Separate the aerodynamic test load and the inertial test load in the test load, and calculate the x-coordinate of the center of gravity of the inertial test load g , z g , y g , where x g is the coordinate of the center of gravity of the inertial test load in the aircraft's longitudinal direction; z g is the coordinate of the center of gravity of the inertial test load in the aircraft's lateral direction; y g is the coordinate of the center of gravity of the inertial test load in the aircraft's vertical direction; Step 2: Measure and sense the aircraft attitude: At the structure with high stiffness near the center of gravity of the inertial test load, arrange displacement measurement points, and calculate the aircraft attitude based on the displacements of the displacement measurement points; or, Install an attitude sensing gyroscope at or near the center of gravity of the inertial test load to measure the aircraft attitude; or, Establish an attitude coordinate system parallel to the three axes of the whole-aircraft coordinate system with the center of gravity of the inertial test load as the origin, reconstruct the whole-aircraft model based on the structural displacement response in the whole-aircraft coordinate system, compare it with the set whole-aircraft model, obtain the transformation relationship of the attitude coordinate system in the reconstructed whole-aircraft model and the set whole-aircraft model, and obtain the aircraft attitude; Step 3: Aircraft attitude analysis: Judge whether the change in the aircraft attitude exceeds the limit. If so, perform aircraft attitude adjustment; Step 4: Aircraft attitude adjustment: Calculate the adjustment amount at the aircraft constraint points and use actuators for adjustment: Adjustment amount of aircraft restraint point in the flight direction The adjustment amount Δy in the vertical direction at the aircraft restraint point = ΔY + y m -y θ1 -y γ1 ; Lateral adjustment amount of aircraft restraint points Wherein, x θ1 = x z + (x m - x z ) cos θ - (y m - y z ) sin θ, y θ1 = y z + (y m - y z ) cos θ + (x m - x z ) sin θ; y γ1 = y z + (y m - y z ) cos γ - (z m - z z ) sin γ, z γ1 = z z + (z m - z z ) cos γ + (y m - y z ) sin γ; x m is the coordinate of the aircraft restraint point in the heading direction, and ΔX is the translational displacement of the aircraft attitude change center of gravity in the heading direction; y m It is the coordinate of the aircraft restraint point in the vertical direction, and ΔY is the translation amount of the aircraft attitude change center of gravity in the vertical direction; z m It is the coordinate of the aircraft restraint point in the lateral direction, and ΔZ is the translational displacement of the aircraft attitude change center of gravity in the lateral direction; θ is the pitch angle of the aircraft; is the yaw angle of the aircraft; γ is the roll angle of the aircraft; In step one, the coordinates of the center of gravity of the inertia test load in the aircraft's flight direction The vertical coordinate y of the center of gravity of the inertia test load on the aircraft g , take the vertical coordinate of the designed center of gravity of the aircraft; Lateral coordinates of the center of gravity of the inertia test load on the aircraft Wherein, n is the number of node inertial test loads; F yi is the inertial test load of the i-th node; x i is the coordinate of the inertial test load of the i-th node in the aircraft's course direction; z i It is the coordinate of the inertial test load of the i-th node in the lateral direction of the aircraft.

2. The aircraft full-aircraft static test attitude adjustment method according to claim 1, characterized in that, In step 2, at the structure with relatively high stiffness near the center of gravity of the inertial test load, arrange displacement measurement points, and calculate the aircraft attitude based on the displacements of the displacement measurement points. Specifically: Arrange 4 displacement measurement points at the structure with relatively high stiffness near the center of gravity of the inertial test load; Calculate the actual rigid body displacements of the 4 displacement measurement points as the measured displacements: The actual displacement Δx of the i-th displacement measurement point in the flight direction of the aircraft i = Δx ic - Δx is ; The actual displacement Δy of the i-th displacement measurement point in the vertical direction of the aircraft i = Δy ic - Δy is ; The actual displacement Δz of the i-th displacement measurement point in the lateral direction of the aircraft i = Δz ic - Δz is ; Wherein, Δx ic is the measured displacement of the i-th displacement measurement point in the flight direction of the aircraft; Δx is is the elastic displacement calculated by finite element for the i-th displacement measurement point in the flight direction of the aircraft; Δy ic is the measured displacement of the i-th displacement measurement point in the vertical direction of the aircraft; Δy is is the elastic displacement calculated by finite element for the i-th displacement measurement point in the vertical direction of the aircraft; Δz ic is the measured displacement of the i-th displacement measurement point in the lateral direction of the aircraft; Δz is is the elastic displacement calculated by finite element method of the i-th displacement measurement point in the lateral direction of the aircraft; Calculate the center of gravity translation amount of the aircraft attitude change: Translation of the center of gravity in the flight direction due to aircraft attitude change Vertical translation amount of the center of gravity during aircraft attitude change Lateral translation of the center of gravity due to aircraft attitude change Calculate the pitch angle, roll angle, and yaw angle of the aircraft to obtain the aircraft attitude: Aircraft pitch angle Aircraft roll angle Aircraft yaw angle 3. The aircraft full-aircraft static test attitude adjustment method according to claim 1, characterized in that, In step 3, judge that if the translation amounts of the center of gravity of the aircraft attitude change in the heading, vertical, and lateral directions exceed 3 mm, or the pitch angle, roll angle, and yaw angle are greater than 1°, then perform aircraft attitude adjustment.

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