Flap inclination amount calculation method

Abstract

The invention provides a flap inclination amount calculation method, and belongs to the technical field of aviation, and the method comprises the steps: obtaining the three-dimensional coordinates of rocker arm control points at two sides when a lead screw actuator is normal and has a fault when the lead screw actuator has different flap configurations in a flap control surface, according to the three-dimensional coordinates of the first side rocker arm control point and the three-dimensional coordinates of the flap rocker arm rotating center point on the side during normal and fault, the deflection angle of the side rocker arm is obtained; obtaining the deflection angle of the rocker arm on the side according to the three-dimensional coordinates of the control point of the rocker arm on the second side and the three-dimensional coordinates of the rotating center point of the flap rocker arm on the side during normal and fault; according to the deflection angles of the rocker arms on the two sides, the length of the rocker arms and the distance between the rocker arm control points on the two sides in the fault state, the flap inclination angle under the lead screw actuator fault condition is obtained; and taking the maximum flap inclination angle in all flap configurations as the maximum inclination amount of the flap for design. The method can accurately evaluate the inclination amount of the flap, and is high in universality and wide in application range.

Description

Technical Field

[0001] The present application relates to the field of aviation technology, and in particular to a method for calculating the tilt amount of a flap. Background Art

[0002] All military and civilian aircraft need to be equipped with flaps and control surfaces, but not all aircraft have flap tilt protection function. The flap tilt protection function prevents the flaps from tilting beyond a certain amount and damaging the aircraft structure or affecting the aircraft's aerodynamic performance.

[0003] Among the existing small civil aircraft, the old turboprop aircraft (MA60, ATR-72, Q400, ERJ-145, CRJ200) do not have the flap tilt protection function, and the new turbofan aircraft (ERJ-190, ARJ-21) are equipped with flap tilt sensors on the outer flaps to prevent the flap control surfaces from over-tilting; the existing large and medium-sized aircraft (B737, B777, B787, A320) are all equipped with tilt sensors or proximity sensors to prevent the flap control surfaces from over-tilting and causing structural damage.

[0004] It can be seen from the above aircraft that not all aircraft require flap tilt sensors for flap over-tilt protection. Therefore, analyzing and calculating whether the flaps may be over-tilted is a key factor in determining whether the aircraft needs flap tilt protection function, that is, calculating whether the maximum possible tilt of the flaps exceeds the maximum tilt limit allowed by the flap structure.

[0005] However, there is no article describing the method of calculating the maximum tilt of the flaps. The traditional method is to overdesign the stiffness of the control surface, or to determine whether the tilt occurs by measuring whether the angle difference between the two flap tilt sensors in the same control surface exceeds a threshold. These methods greatly increase the weight of the aircraft and fail to clarify the specific value of the maximum tilt that actually occurs. Therefore, it is urgent to invent a method for calculating the tilt of the flaps. Summary of the invention

[0006] In view of this, an embodiment of the present application provides a method for calculating the tilt amount of a flap, which at least partially solves the problem that the method for calculating the maximum tilt amount of a flap in the prior art greatly increases the weight of the aircraft and fails to clearly define the specific value of the maximum tilt amount that actually occurs.

[0007] The present application provides a method for calculating a flap tilt amount, the method comprising:

[0008] Acquire the three-dimensional coordinates of the rocker arm control points on both sides of the flap control surface when the lead screw actuator is in a normal state and the three-dimensional coordinates of the rocker arm control points on both sides when the lead screw actuator is in a fault state in different flap configurations, wherein the two sides are respectively a first side and a second side;

[0009] Obtain the three-dimensional coordinates of the rotation center points of the flap rocker arms on both sides;

[0010] For each flap configuration, the rocker arm deflection angle of the first side is obtained according to the three-dimensional coordinates of the rocker arm control point of the first side in the normal state, the three-dimensional coordinates of the rocker arm control point of the side in the fault state, and the three-dimensional coordinates of the rotation center point of the flap rocker arm on the side; the rocker arm deflection angle of the second side is obtained according to the three-dimensional coordinates of the rocker arm control point of the second side in the normal state, the three-dimensional coordinates of the rocker arm control point of the side in the fault state, and the three-dimensional coordinates of the rotation center point of the flap rocker arm on the side;

[0011] For each flap configuration, according to the rocker arm deflection angle on the first side, the rocker arm deflection angle on the second side, the rocker arm length, and the distance between the rocker arm control points on both sides in the fault state, the flap tilt angle in the case of a screw actuator failure is obtained;

[0012] According to the flap inclination angle corresponding to each flap configuration, the maximum flap inclination angle in the flap configuration is obtained, and the maximum flap inclination angle is used as the maximum flap inclination amount for design.

[0013] According to a specific implementation of an embodiment of the present application, obtaining the flap tilt angle in the case of a screw actuator failure according to the rocker arm deflection angle on the first side, the rocker arm deflection angle on the second side, the rocker arm length, and the distance between the rocker arm operating points on both sides in the fault state includes:

[0014] Project the coordinate point of the flap rocker arm and the flap connection point on the second side in the fault state to the flap control surface on the first side to obtain the projection point P; assume that the flap rocker arm and the flap connection point on the second side in the normal state are point Q, the flap rocker arm and the flap connection point on the first side in the normal state are point N, and assume that the distance from the projection point P to the point N is the relative displacement s of the flap connection point;

[0015] Obtaining a relative displacement s of a flap connection point according to a rocker arm deflection angle on a first side, a rocker arm deflection angle on a second side, and a rocker arm length;

[0016] According to the three-dimensional coordinates of the flap rocker arm and the flap connection point N on the first side in the normal state and the three-dimensional coordinates of the flap rocker arm and the flap connection point Q on the second side in the normal state, obtain the distance m between point N and point Q;

[0017] The flap tilt angle in the case of a screw actuator failure is calculated based on the distance m, the relative displacement s of the flap connection point and the angle ∠NPQ of △QPN.

[0018] According to a specific implementation of an embodiment of the present application, the calculation formula of the relative displacement s of the flap connection point is:

[0019] s=2r*sin((α-θ) / 2),

[0020] Wherein, r is the length of the rocker arm, α is the deflection angle of the rocker arm on the first side, and θ is the deflection angle of the rocker arm on the second side.

[0021] According to a specific implementation of the embodiment of the present application, the angle ∠NPQ of △QPN is obtained by three-dimensional digital analog measurement.

[0022] According to a specific implementation of the embodiment of the present application, the calculation formula of the flap inclination angle is:

[0023] sin(β) / s=sin(γ) / m,

[0024] Among them, β is the flap inclination angle, and γ is the angle ∠NPQ of △QPN.

[0025] According to a specific implementation method of an embodiment of the present application, the three-dimensional coordinates of the rocker arm control points on both sides of the flap control surface when the screw actuator is in a normal state in different flap configurations are obtained, wherein 70% of the flap control surface aerodynamic load and the maximum control load of the flap ball screw actuator are used when the screw actuator is in a normal state.

[0026] According to a specific implementation of the embodiment of the present application, the screw actuator failure conditions include screw actuator breakage, screw actuator jamming, and torque tube breakage.

[0027] According to a specific implementation of an embodiment of the present application, the flap configuration includes a take-off configuration, a cruise configuration, an approach configuration, a landing configuration and a go-around configuration.

[0028] According to a specific implementation of an embodiment of the present application, the three-dimensional coordinate system is an aircraft coordinate system.

[0029] Beneficial effects:

[0030] The flap tilt calculation method in the embodiment of the present application is used to calculate the tilt of the flap control surface of the aircraft, that is, the inclination of the flap surface caused by the asynchronous movement of two actuators of the same flap. The calculation of the flap tilt requires first analyzing the flap tilt caused by the failure of any ball screw actuator, and then calculating the displacement change of the flap control surface and the rocker arm connection point according to the different loads borne by the control surface under the failure condition, and then using the present invention to calculate the tilt of the flap control surface. The method converts the change displacement of the point on the flap control surface connected to the rocker arm into the rocker arm rotation angle, and finally projects the rocker arm deviation angle into the flap surface by the projection method, and finally obtains the tilt angle.

[0031] This method is scientific and reasonable, has strong versatility, and has a wide range of applications. It is suitable for aircraft with common flap control surfaces driven by two ball screw actuators and a flap motion mechanism that uses a rocker / support arm sinking hinge motion mechanism. This method can accurately evaluate the flap tilt amount, and has a decisive influence on the necessity of the flap tilt protection function of military and civilian aircraft. If the calculated flap tilt amount does not exceed the flap structure limit, it can reduce a lot of weight for the aircraft and reduce a lot of maintenance costs for airlines. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 is a schematic diagram of a deflection angle of a flap rocker arm on one side according to an embodiment of the present invention;

[0034] Figure 2 A schematic diagram of flap tilt calculation according to an embodiment of the present invention;

[0035] Figure 3 for Figure 2 A partial enlarged view of .

[0036] In the figure: 1-flap support arm, 2-rocker arm rotation center, 3-left flap rocker arm in normal state, 4-left flap rocker arm in fault state, 5-flap control surface in fault state, 6-flap control surface in normal state, 7-left ball screw actuator in normal state, 8-right ball screw actuator in fault state, 9-wing rear beam, 10-left ball screw actuator in fault state, 11-right ball screw actuator in normal state. DETAILED DESCRIPTION

[0037] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0038] The following describes the implementation methods of the present application through specific specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0039] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0040] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The illustrations only show the components related to the present application rather than being drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed at will, and the component layout may also be more complicated.

[0041] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects described may be practiced without these specific details.

[0042] The present application embodiment provides a flap tilt amount calculation method. Figures 1 to 3 Described in detail, the method comprises the following steps:

[0043] Step S101, obtaining the three-dimensional coordinates of the rocker arm control points on both sides of the flap control surface when the lead screw actuator is in a normal state and the three-dimensional coordinates of the rocker arm control points on both sides when the lead screw actuator is in a fault state in different flap configurations, wherein the two sides are respectively a first side and a second side;

[0044] Step S102, obtaining the three-dimensional coordinates of the rotation center points of the flap rocker arms on both sides;

[0045] Step S103: for each flap configuration, according to the three-dimensional coordinates of the rocker arm control point of the first side in the normal state, the three-dimensional coordinates of the rocker arm control point of the side in the fault state, and the three-dimensional coordinates of the rotation center point of the flap rocker arm on the side, obtain the rocker arm deflection angle of the first side; according to the three-dimensional coordinates of the rocker arm control point of the second side in the normal state, the three-dimensional coordinates of the rocker arm control point of the side in the fault state, and the three-dimensional coordinates of the rotation center point of the flap rocker arm on the side, obtain the rocker arm deflection angle of the second side;

[0046] Step S104, for each flap configuration, according to the rocker arm deflection angle on the first side, the rocker arm deflection angle on the second side, the rocker arm length, and the distance between the rocker arm control points on both sides in the fault state, obtain the flap tilt angle in the case of a screw actuator failure;

[0047] Step S105: according to the flap inclination angle corresponding to each flap configuration, obtain the maximum flap inclination angle in the flap configuration, and use the maximum flap inclination angle as the maximum flap inclination amount for design.

[0048] The flap tilt calculation method of the present embodiment is used to calculate the tilt of the flap control surface of the aircraft, that is, the tilt of the flap surface caused by the asynchronous movement of two actuators of the same flap. The calculation of the flap tilt requires first analyzing the flap tilt caused by the failure of any ball screw actuator, and then calculating the displacement change of the connection point between the flap control surface and the rocker arm according to the different loads borne by the control surface under the failure condition, and then using the present invention to calculate the tilt of the flap control surface. The method converts the change displacement of the point on the flap control surface connected to the rocker arm into the rotation angle of the rocker arm, and finally projects the rocker arm deviation angle into the flap surface by the projection method, and finally obtains the tilt angle.

[0049] This method is scientific and reasonable, has strong versatility, and has a wide range of applications. It is suitable for aircraft with common flap control surfaces driven by two ball screw actuators and a flap motion mechanism that uses a rocker / support arm sinking hinge motion mechanism. This method has a decisive influence on the necessity of flap tilt protection function for military and civilian aircraft. If the calculated result of flap tilt does not exceed the flap structure limit, the aircraft can be significantly reduced in weight and the airline's maintenance work can also reduce a lot of costs.

[0050] When implementing it, refer to Figure 2, taking the left side in the figure as the first side and the right side in the figure as the second side, the specific structure of the flap is shown in the figure, including a wing rear beam 9, a flap support arm 1 connected to the wing rear beam, a flap rudder surface, and a flap rocker arm. The flap motion mechanism consists of a flap rocker arm, a support arm and a ball screw actuator connected to the rocker arm; the flap rudder surface is connected to two flap rockers through connecting ears and a pin shaft; one end of the flap rocker arm is connected to the ear piece on the lower surface of the flap rudder surface, and the other end is connected to the rear end of the flap support arm 1 by a combination of a bushing, a pin shaft and a bolt, and the middle of the flap rocker arm is connected to the ear shaft of the ball screw actuator through a fork ear; one end of the flap support arm 1 is connected to the flap rocker arm, and the other end is connected to the wing box through a transition joint and a high locking bolt; the ear shaft at one end of the screw actuator is connected to the rocker arm fork ear, and the other end is connected to the support of the wing rear beam. For example, one end of the left flap rocker arm is connected to the left side of the flap control surface, and the other end is connected to the rotation center O of the left flap rocker arm, the middle part of the left flap rocker arm is connected to the left ball screw actuator, one end of the right flap rocker arm is connected to the right side of the flap control surface, and the other end is connected to the rotation center O of the right flap rocker arm, and the middle part of the right flap rocker arm is connected to the right ball screw actuator.

[0051] Assume that the connection point between the left flap rocker arm and the flap in the normal state is point N, the connection point between the right flap rocker arm and the flap in the normal state is point Q, the projection point of the coordinate point of the right flap rocker arm and the flap connection point to the left flap control surface in the fault state is point P, the rocker arm control point of the left screw actuator in the normal state is point A, and the rocker arm control point of the left screw actuator in the fault state is point B.

[0052] Further, the flap tilt angle under the condition of a screw actuator failure is obtained according to the rocker arm deflection angle on the first side, the rocker arm deflection angle on the second side, the rocker arm length, and the distance between the rocker arm operating points on both sides in the fault state, including:

[0053] Project the coordinate point of the flap rocker arm and the flap connection point on the second side in the fault state to the flap control surface on the first side to obtain the projection point P; assume that the flap rocker arm and the flap connection point on the second side in the normal state are point Q, the flap rocker arm and the flap connection point on the first side in the normal state are point N, and assume that the distance from the projection point P to the point N is the relative displacement s of the flap connection point;

[0054] Obtaining a relative displacement s of a flap connection point according to a rocker arm deflection angle on a first side, a rocker arm deflection angle on a second side, and a rocker arm length;

[0055] According to the three-dimensional coordinates of the flap rocker arm and the flap connection point N on the first side in the normal state and the three-dimensional coordinates of the flap rocker arm and the flap connection point Q on the second side in the normal state, obtain the distance m between point N and point Q;

[0056] The flap tilt angle in the case of a screw actuator failure is calculated based on the distance m, the relative displacement s of the flap connection point and the angle ∠NPQ of △QPN.

[0057] Furthermore, the calculation formula of the relative displacement s of the flap connection point is:

[0058] s=2r*sin((α-θ) / 2),

[0059] Wherein, r is the length of the rocker arm, α is the deflection angle of the rocker arm on the first side, and θ is the deflection angle of the rocker arm on the second side.

[0060] Furthermore, the angle ∠NPQ of △QPN is obtained by three-dimensional digital modeling measurement.

[0061] Furthermore, the calculation formula of the flap inclination angle is:

[0062] sin(β) / s=sin(γ) / m,

[0063] Among them, β is the flap inclination angle, and γ is the angle ∠NPQ of △QPN.

[0064] In one embodiment, the three-dimensional coordinates of the flap rocker arms and flap connection points on both sides of the flap control surface when the screw actuator is in a normal state in different flap configurations are obtained, wherein 70% of the flap control surface aerodynamic load and the maximum control load of the flap ball screw actuator are used when the screw actuator is in a normal state.

[0065] In one embodiment, the screw actuator failure conditions include screw actuator breakage, screw actuator jamming, and torque tube breakage.

[0066] In one embodiment, the flap configurations include a takeoff configuration, a cruise configuration, an approach configuration, a landing configuration, and a go-around configuration.

[0067] In one embodiment, the three-dimensional coordinate system is an aircraft coordinate system.

[0068] The method of the present application is described in detail below with a specific calculation process. The main principle is to calculate through a three-dimensional projection algorithm, including the following steps:

[0069] (1) Obtaining design input: The three-dimensional coordinates of two rocker arm control points in a flap control surface under normal conditions are calculated using the finite element analysis method, including all flap configurations (takeoff configuration, cruise configuration, approach configuration, landing configuration and go-around configuration). The coordinate system is the aircraft coordinate system. When calculating the three-dimensional coordinates of the control points under normal conditions, 70% of the flap control surface aerodynamic load and the maximum control load of the flap ball screw actuator are used; at the same time, the three-dimensional coordinates of the two rocker arm control points in the flap control surface under any ball screw actuator failure state are calculated using the finite element analysis method, including all flap configurations (takeoff configuration, approach configuration, landing configuration and go-around configuration). The coordinate system is the aircraft coordinate system; the failure modes of the screw actuator consider screw breakage failure and jamming failure.

[0070] (2) Taking the left rocker arm as an example, calculate the rocker arm deflection angle α under different failure modes and different flap configurations, as follows: Figure 1 As shown, using the coordinates of the flap rocker arm rotation center point O (x1, y1, z1), the rocker arm operating point A (x2, y2, z2) in the normal state of the screw actuator, and the rocker arm operating point B (x3, y3, z3) in the fault state of the screw actuator, the side length of OA is a, the side length of OB is b, and the side length of AB is c, the three side lengths of the triangle △OAB are first obtained:

[0071]

[0072] The rocker arm deflection angle α is calculated according to the arc cosine formula:

[0073] α=arcos((a 2 +b 2 -c 2 ) / 2ab).

[0074] (3) Calculate the relative deflection angle α-θ of the two flap rocker arms in the rudder surface, where θ is the deflection angle of the right rocker arm.

[0075] like Figure 2 , Figure 3 As shown, let α be the rocker arm deflection angle at the faulty FBSA (screw actuator), θ be the rocker arm deflection angle at the normally working FBSA, and the calculation results include the failures of ball screw actuator breakage, jamming, and torque tube breakage in the flaps in takeoff configuration, approach configuration, landing configuration, and go-around configuration;

[0076] The relative displacement s (i.e., the PN side length of △PQN) between the left flap rocker arm and the flap connection point under various fault conditions is calculated according to the formula s=2r*sin((α-θ) / 2), where r is the length of the rocker arm;

[0077] The angle ∠QPN of △QPN is measured by three-dimensional digital modeling and is recorded as γ;

[0078] Calculate the flap tilt angle β under various fault conditions according to the triangle sine formula sin(β) / s=sin(γ) / m;

[0079] The maximum value of all flap inclination angles β calculated above is the maximum inclination angle of the aircraft.

[0080] The present invention is used to calculate the inclination of the flap control surface of an aircraft, that is, the inclination of the flap surface caused by the asynchronous movement of two actuators of the same flap. The calculation of the flap inclination requires first analyzing the flap inclination caused by the breakage and jamming of any ball screw actuator or the breakage and jamming of any torque tube on the flap motion line, and then calculating the displacement change of the connection point between the flap control surface and the rocker arm according to the different loads borne by the control surface under the fault condition, and then using the present invention to calculate the inclination of the flap control surface, the method converts the displacement change of the point on the flap control surface connected to the rocker arm into the rocker arm rotation angle, and finally projects the rocker arm deviation angle into the flap surface by the projection method, and finally obtains the inclination angle.

[0081] The application content can be used to evaluate whether the aircraft exceeds the flap structural limitations, an important conclusion that can be used to determine whether the aircraft requires flap tilt protection.

[0082] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A flap tilt amount calculation method, characterized in that: The method comprises: Acquire the three-dimensional coordinates of the rocker arm control points on both sides of the flap control surface when the lead screw actuator is in a normal state and the three-dimensional coordinates of the rocker arm control points on both sides when the lead screw actuator is in a fault state in different flap configurations, wherein the two sides are respectively a first side and a second side; Obtain the three-dimensional coordinates of the rotation center points of the flap rocker arms on both sides; For each flap configuration, the rocker arm deflection angle of the first side is obtained according to the three-dimensional coordinates of the rocker arm control point of the first side in the normal state, the three-dimensional coordinates of the rocker arm control point of the side in the fault state, and the three-dimensional coordinates of the rotation center point of the flap rocker arm on the side; the rocker arm deflection angle of the second side is obtained according to the three-dimensional coordinates of the rocker arm control point of the second side in the normal state, the three-dimensional coordinates of the rocker arm control point of the side in the fault state, and the three-dimensional coordinates of the rotation center point of the flap rocker arm on the side; For each flap configuration, according to the rocker arm deflection angle on the first side, the rocker arm deflection angle on the second side, the rocker arm length, and the distance between the rocker arm control points on both sides in the fault state, the flap tilt angle in the case of a screw actuator failure is obtained; According to the flap inclination angle corresponding to each flap configuration, the maximum flap inclination angle in the flap configuration is obtained, and the maximum flap inclination angle is used as the maximum flap inclination amount for design.

2. The flap tilt amount calculation method according to claim 1, characterized in that: The method of obtaining the flap tilt angle in the case of a screw actuator failure according to the rocker arm deflection angle on the first side, the rocker arm deflection angle on the second side, the rocker arm length, and the distance between the rocker arm operating points on both sides in the fault state comprises: Project the coordinate point of the flap rocker arm and the flap connection point on the second side in the fault state to the flap control surface on the first side to obtain the projection point P; assume that the flap rocker arm and the flap connection point on the second side in the normal state are point Q, the flap rocker arm and the flap connection point on the first side in the normal state are point N, and assume that the distance from the projection point P to the point N is the relative displacement s of the flap connection point; Obtaining a relative displacement s of a flap connection point according to a rocker arm deflection angle on a first side, a rocker arm deflection angle on a second side, and a rocker arm length; According to the three-dimensional coordinates of the flap rocker arm and the flap connection point N on the first side in the normal state and the three-dimensional coordinates of the flap rocker arm and the flap connection point Q on the second side in the normal state, obtain the distance m between point N and point Q; The flap tilt angle in the case of a screw actuator failure is calculated based on the distance m, the relative displacement s of the flap connection point and the angle ∠NPQ of △QPN.

3. The flap tilt amount calculation method according to claim 2, characterized in that: The calculation formula of the relative displacement s of the flap connection point is: s=2r*sin((α-θ) / 2), Wherein, r is the length of the rocker arm, α is the deflection angle of the rocker arm on the first side, and θ is the deflection angle of the rocker arm on the second side.

4. The flap tilt amount calculation method according to claim 2, characterized in that: The angle ∠NPQ of △QPN is obtained by three-dimensional digital modeling measurement.

5. The flap tilt amount calculation method according to claim 4, characterized in that: The calculation formula of the flap inclination angle is: sin(β) / s=sin(γ) / m, Among them, β is the flap inclination angle, and γ is the angle ∠NPQ of △QPN.

6. The flap tilt amount calculation method according to claim 1, characterized in that: The three-dimensional coordinates of the rocker arm control points on both sides of the flap control surface when the screw actuator is in a normal state in different flap configurations are obtained, wherein 70% of the flap control surface aerodynamic load and the maximum control load of the flap ball screw actuator are used when the screw actuator is in a normal state.

7. The flap tilt amount calculation method according to claim 1, characterized in that: The screw actuator failure conditions include screw actuator breakage, screw actuator jamming and torque tube breakage.

8. The flap tilt amount calculation method according to claim 1, characterized in that: The flap configurations include a takeoff configuration, a cruise configuration, an approach configuration, a landing configuration and a go-around configuration.

9. The flap tilt amount calculation method according to claim 1, characterized in that: The three-dimensional coordinate system is an aircraft coordinate system.

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