Tilt-rotor aircraft rotor center six-force element test method and test platform

Abstract

The invention provides a tilt-rotor aircraft rotor center six-force element test method and test platform, and belongs to the technical field of tilt-rotor aircrafts, and the method comprises the steps: installing the center of a rotor on a test platform, and obtaining the load of the rotor through six force sensors, three of the six force sensors are vertically arranged, two of the six force sensors are in heading arrangement, and one of the six force sensors is in lateral arrangement, so that a statically determinate structure is formed; controlling the rotor to move so that the rotor simulates various working conditions in flight, and acquiring force sensor data under each working condition through six sensors; according to force sensor data collected by six sensors, six force elements of the center of the rotor wing are obtained through calculation based on the stress condition of the center of the rotor wing, and therefore force in three directions and torque in the three directions of the center of the rotor wing are obtained.

Description

Technical Field

[0001] This application belongs to the field of tiltrotor aircraft technology, and specifically relates to a method and testing platform for testing the six force elements at the center of the tiltrotor aircraft rotor. Background Technology

[0002] A tiltrotor aircraft is a type of aircraft that integrates the characteristics of a fixed-wing aircraft and a helicopter. The tiltrotor system controls the rotor shaft to rotate 90°, giving it both the vertical takeoff and landing and hovering capabilities of a conventional helicopter and the high-speed cruise flight capabilities of a turboprop aircraft. Therefore, a tiltrotor aircraft possesses the dual characteristics of both helicopters and fixed-wing aircraft. However, during the tilting process, because the rotor disk and nacelle structure rotate at different speeds, and the aircraft is still moving at high speed, and because the motions of the three components are highly coupled, it is currently impossible to completely and accurately obtain the six rotor center force elements (i.e., forces in three directions Fx, Fy, and Fz, and moments in three directions Mx, My, and Mz) at any angle and under any total moment and periodic torque conditions during the entire tilting process of a tiltrotor aircraft.

[0003] Therefore, a test method for the six force elements at the center of the rotor of a tiltrotor aircraft is needed to obtain the correspondence between the engine output power, total torque, cyclic torque control and other related information such as aircraft attitude and the six force elements at the center of the rotor, so as to provide test data support for the overall design of tiltrotor aircraft. Summary of the Invention

[0004] The purpose of this application is to provide a method and platform for testing the six force elements at the center of the tiltrotor aircraft rotor, in order to solve or mitigate at least one of the problems in the background art.

[0005] The technical solution of this application is: a method for testing the six force elements at the center of a tiltrotor aircraft rotor, comprising:

[0006] The rotor's center was mounted on a test platform, and the rotor's load was acquired using six force sensors. The yaw load was borne by two yaw force sensors, the lateral load by one lateral force sensor, and the vertical load by three vertical force sensors. The yaw torque was balanced by a force couple formed by the three vertical force sensors and the lateral force sensor. The vertical torque was balanced by a force couple formed by the two yaw force sensors and the lateral force sensor. The lateral torque was balanced by a force couple formed by the two yaw force sensors and the three vertical force sensors.

[0007] The rotor motion is controlled to simulate various operating conditions during flight, and force sensor data for each operating condition is acquired through six sensors.

[0008] Force sensor data collected by six sensors is used to calculate the six force elements at the rotor center based on the force conditions at the rotor center, thereby obtaining the forces and torques in three directions at the rotor center.

[0009] Preferably, the calculation process based on the force conditions at the rotor center is as follows:

[0010]

[0011] In the formula, F x F y F z M represents the forces in the x, y, and z directions at the rotor center. x M y M z These are the torques in three directions around the rotor center; F x2 F x2 F represents the force in the x-direction measured by the force sensor. y1 F is the force in the y-direction measured by the force sensor. z1 F z2 F z3 The x-axis force measured by the force sensor is represented by x0, y0, and z0, which are the rotor center coordinates. The vertical force sensor coordinates are represented by x1, y1, z1, x2, y2, z2, x3, y3, and z3.

[0012] Preferably, if the rotor tilts by an angle β, the calculation process based on the force at the rotor center is as follows:

[0013] .

[0014] In addition, this application also provides a test platform for realizing the six force elements at the center of the tiltrotor aircraft rotor as described above, characterized in that the test platform includes: a mounting base, a support structure, a force sensor, an adjustable structure, and a nacelle structure.

[0015] The mounting base is fixed to the test platform by connectors;

[0016] The support structure is fixed to the mounting base and is used to install the adjustable structure;

[0017] The nacelle structure has a nacelle connector at its front end, and the nacelle structure and nacelle connector are supported on a mounting base or support structure by force sensors and adjustable structures.

[0018] The structure comprises six force sensors, three vertically positioned, two directionally positioned, and one laterally positioned, forming a statically determinate structure. The upper end of the nacelle structure is connected to the rotor. The rotor load is transmitted to the mounting base through the six force sensors. The directional load is borne by two directional force sensors, the lateral load by one lateral force sensor, and the vertical load by three vertical force sensors. The directional moment is balanced by a couple formed by the three vertical force sensors and the lateral force sensor. The vertical moment is balanced by a couple formed by the two directional force sensors and the lateral force sensor. The lateral moment is balanced by a couple formed by the two directional force sensors and the three vertical force sensors.

[0019] Preferably, the rigidity of the mounting base and support structure is higher than that of the nacelle structure.

[0020] Preferably, it also includes: a data acquisition system and a control system;

[0021] The data acquisition system is used to capture data from the force sensor in real time, convert the force sensor signal into a digital signal, and store and process it.

[0022] The control system is used to control the rotor to move according to predetermined parameters, including rotational speed and tilt angle;

[0023] This application provides an efficient and accurate six-force element testing method, which can provide strong technical support for the research and development and improvement of tiltrotor aircraft, and ensure that the loads in helicopter mode, fixed-wing aircraft mode and tilt process mode can meet the design requirements for normal flight of the aircraft. Attached Figure Description

[0024] To more clearly illustrate the technical solutions provided in this application, the accompanying drawings will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application.

[0025] Figure 1 This is a schematic diagram of the six-force element test platform at the center of the tiltrotor aircraft rotor of this application.

[0026] Figure 2 This is a schematic diagram illustrating the calculation principle of the six force elements at the rotor center in this application.

[0027] Figure 3 This is a schematic diagram illustrating the principle of calculating the six force elements at the center of the tilting rotor in this application. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings.

[0029] To overcome the problem that the rotor center load of tiltrotor aircraft under various conditions can only be obtained through CFD calculation and has a large error, this application provides a method for testing the six force elements of the rotor center of tiltrotor aircraft.

[0030] like Figure 1 As shown, this application first provides a six-force element test platform for the center of a tiltrotor aircraft rotor. The device includes: a mounting base 1, a support structure 2, multiple force sensors 3, an adjustable structure 4, and a nacelle structure 5.

[0031] The mounting base 1 has several mounting holes 11, and the mounting base 1 can be fixed to the test platform by bolts installed at the mounting holes 11.

[0032] The support structure 2 is fixed to the mounting base 1 for mounting the adjustable structure 4.

[0033] The nacelle structure 5 has a nacelle connector 51 at its front end. The nacelle structure 5 and the nacelle connector 51 are supported on the mounting base 1 or the support structure 2 via force sensors 3 and an adjustable structure 4. There are six force sensors 3, three vertically positioned, two directionally positioned, and one laterally positioned, forming a statically determinate structure. The upper end of the nacelle structure 5 is connected to the rotor system (not shown). The rotor load is transmitted to the mounting base 1 through the six force sensors. Specifically, the directional load on the rotor disk is supported by two directional force sensors, the lateral load by one lateral force sensor, and the vertical load by three vertical force sensors. The directional moment is balanced by a couple formed by the three vertical force sensors and the lateral force sensor. The vertical moment is balanced by a couple formed by the two directional force sensors and the lateral force sensor. The lateral moment is balanced by a couple formed by the two directional force sensors and the three vertical force sensors.

[0034] In some embodiments of this application, the stiffness of the mounting base 1 and the support structure 2 is higher than that of the nacelle structure 5, thereby effectively acquiring and solving the complex and variable rotor load through six force sensors.

[0035] The test platform in this application also includes: a data acquisition system and a control system.

[0036] The data acquisition system is used to capture data from the force sensor in real time, convert the force sensor signal into a digital signal, and store and process it. In some embodiments of this application, the data acquisition system needs to have a sufficient sampling rate to ensure the capture of rapidly changing signals; for example, the sampling rate of the data acquisition system can be above 10 kHz to achieve a high sampling rate. Furthermore, the data acquisition system can employ shielded cables or add filters to form anti-interference measures to reduce the impact of noise on the measurement results.

[0037] The control system is used to control the movement of the rotor system, such as parameters like rotational speed and tilt angle. In some embodiments of this application, the control system can employ a closed-loop control system to control the rotor's speed and angle, for example, through a motor drive and servo system. The control system and the data acquisition system are interconnected and synchronized to trigger tests under specific operating conditions.

[0038] Finally, based on the aforementioned testing platform, this application also provides a method for testing the six force elements at the center of a tiltrotor aircraft rotor, the method comprising the following steps:

[0039] S10: The center of the rotor is mounted on the test platform. The rotor load is obtained through six force sensors. The directional load is jointly subjected to two directional force sensors, the lateral load is subjected to one lateral force sensor, and the vertical load is jointly subjected to three vertical force sensors. The torque around the directional load is balanced by a force couple formed by three vertical force sensors and the lateral force sensor. The torque around the vertical load is balanced by a force couple formed by two directional force sensors and the lateral force sensor. The torque around the lateral load is balanced by a force couple formed by two directional force sensors and three vertical force sensors.

[0040] S20 controls the rotor system to move and simulate various operating conditions in flight, such as acceleration, deceleration, pitch, roll, etc. It acquires force sensor data for each operating condition through six sensors, which are force and torque in three directions.

[0041] The S30 uses force sensor data collected by six sensors to calculate and obtain the six force elements at the rotor center based on the force conditions at the rotor center. For example, Figure 2 As shown, the solution method is as follows:

[0042]

[0043] In the formula, F x F y F z The forces M are located at the rotor center in the x (heading), y (lateral), and z (vertical) directions. x M y M zThese are the torques in three directions around the rotor center; F x2 F x2 F represents the force in the x-direction measured by the force sensor. y1 F is the force in the y-direction measured by the force sensor. z1 F z2 F z3 The x-axis force measured by the force sensor is represented by x0, y0, and z0, which are the rotor center coordinates. The vertical force sensor coordinates are represented by x1, y1, z1, x2, y2, z2, x3, y3, and z3.

[0044] The six equations above can be used to solve for the six force elements at any time of the rotor center. By understanding the relationship between the obtained six force elements and the engine output power, total torque, and cyclic torque, the force transmission characteristics of the aircraft mounting structure can be optimized, and the structural weight of the aircraft can be effectively controlled, thereby further improving the carrying capacity of the aircraft platform.

[0045] In some embodiments of this application, the testing environment used includes the ground environment inside the factory and the wind tunnel environment. If the test is conducted in the ground environment, it is necessary to simulate the airflow conditions during flight, such as using fans or other equipment to generate a stable wind speed. If the test is conducted in the wind tunnel environment, airflow parameters such as speed, direction and turbulence can be controlled more precisely.

[0046] It should be noted that when the rotor tilts, the above six equations must take into account the influence and changes in the tilt angle. For example... Figure 3 As shown, assuming the rotor shaft tilts by an angle β, i.e. deflects by an angle β around the Y-axis, the expression for the six force elements at the rotor center at this moment is as follows:

[0047] .

[0048] This application provides an efficient and accurate six-force element testing method, which can provide strong technical support for the research and development and improvement of tiltrotor aircraft, and ensure that the loads in helicopter mode, fixed-wing aircraft mode and tilt process mode can meet the design requirements for normal flight of the aircraft.

[0049] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method of testing a rotor center six force element of a tiltrotor aircraft, comprising: The application relates to a rotor center installation test platform. The rotor center is installed on a test platform, and the load of the rotor is obtained through six force sensors, wherein the heading load is borne by two heading force sensors, the lateral load is borne by one lateral force sensor, the vertical load is borne by three vertical force sensors, the moment around the heading is balanced by three vertical force sensors and a lateral force sensor, the moment around the vertical is balanced by two heading force sensors and a lateral force sensor, and the moment around the lateral is balanced by two heading force sensors and three vertical force sensors. The rotor is controlled to move to simulate various working conditions in flight, and the force sensor data under each working condition is obtained through the six sensors. The six force elements of the rotor center are obtained through calculation based on the force condition of the rotor center, so that the force in three directions and the moment in three directions of the rotor center are obtained.

2. The tilt-rotor aircraft rotor center of six force element test method of claim 1 wherein, The process of calculation based on the force condition of the rotor center is as follows: ； F x , F y , F z are the forces in the heading, lateral and vertical directions of the rotor center respectively, M x , M y , M z are the moments in the three directions of the rotor center respectively; F x2 , F x2 are the forces in the x direction measured by the force sensors, F y1 is the force in the y direction measured by the force sensors, F z1 , F z2 , F z3 are the forces in the x direction measured by the force sensors, x0, y0, z0 are the coordinates of the rotor center, x1, y1, z1 and x2, y2, z2 and x3, y3, z3 are the coordinates of the three vertical force sensors respectively.

3. The tilt-rotor aircraft rotor center of six force element test method of claim 2 wherein, If the rotor has a tilt angle beta, the process of calculation based on the force condition of the rotor center is as follows: 。 4. A test platform for testing the center of six forces of a rotor of a tiltrotor aircraft as claimed in any one of claims 1 to 3, characterized in that, The test platform comprises a mounting base (1), a support structure (2), force sensors (3), an adjustable structure (4) and a nacelle structure (5). The mounting base (1) is fixed on the test platform through a connecting piece. The support structure (2) is fixed on the mounting base (1) and used for mounting the adjustable structure (4). The front end of the nacelle structure (5) is provided with a nacelle joint (51), and the nacelle structure (5) and the nacelle joint (51) are supported on the mounting base (1) or the support structure (2) through the force sensors (3) and the adjustable structure (4). The six force sensors (3) are arranged in three vertical directions, two heading directions and one lateral direction, thereby forming a statically determinate structure, the upper end of the nacelle structure (5) is connected with the rotor, the load of the rotor is transmitted to the mounting base (1) through the six force sensors (3), the heading load is borne by two heading force sensors, the lateral load is borne by one lateral force sensor, the vertical load is borne by three vertical force sensors, the moment around the heading is balanced by three vertical force sensors and a lateral force sensor, the moment around the vertical is balanced by two heading force sensors and a lateral force sensor, and the moment around the lateral is balanced by two heading force sensors and three vertical force sensors.

5. The tilt-rotor aircraft rotor center of six force element test platform of claim 4 wherein, The rigidity of the mounting base (1) and the support structure (2) is higher than that of the nacelle structure (5).

6. The tilt-rotor aircraft rotor center of six force element test platform of claim 4 wherein, The application further comprises a data acquisition system and a control system. The data acquisition system is used for capturing the data of the force sensors (3) in real time, converting the signals of the force sensors (3) into digital signals, and storing and processing the signals. The control system is used for controlling the rotor to move according to predetermined parameters, and the predetermined parameters include rotating speed and tilt angle. ​

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