A cross-medium tensile-torsion test platform and tensile-torsion test method for amphibious rotorcraft

Abstract

This invention discloses a cross-medium tension-torsion testing platform and method for amphibious rotorcraft. The testing platform includes a motor, a gear transmission device, a platform support, a test chamber, a dynamic simulation device, and a water level adjustment device. The platform support includes three thrust rods and a Y-shaped bracket. The thrust rods control the platform height and the rotorcraft's flight angle. The rotorcraft's fixed platform is a structure composed of three strain gauges, enabling the measurement of the rotorcraft's tension and torsional torque. The test chamber is a closed, transparent space. By changing the medium of the testing platform, tension-torsion data of the rotorcraft flying in different media can be obtained, enhancing experimental safety. It features a simple and reliable structure, easy assembly and portability, and convenient observation. The dynamic simulation device can simulate the flow of real lakes, rivers, and atmosphere, expanding the experimental dimensions and improving the simulation accuracy.

Description

Technical Field

[0001] This invention relates to the field of force measurement technology and amphibious rotorcraft technology, and is a device and method for cross-medium tension and torsion measurement that can be used in amphibious rotorcraft. Background Technology

[0002] Amphibious cross-medium aircraft integrate three unmanned working systems: airborne, surface, and underwater, enabling simultaneous air, surface, and underwater navigation on a single platform. In the research of amphibious cross-medium rotorcraft, the difference between the water and air environments presents significant challenges to this design. A density difference of hundreds of times makes it difficult for fixed-wing amphibious cross-medium aircraft to cope with complex lift, drag, and buoyancy. Furthermore, the control problems arising from wave-making drag and ground effects during the cross-medium transition have not yet been fully resolved. Summary of the Invention

[0003] To address the control challenges posed by the differences between two media environments for amphibious unmanned aerial vehicles (UAVs), this test platform is primarily used to test the effects of different media on the rotor blades of amphibious UAVs during cross-media flight, including wave drag and ground effects, when the UAV emerges from the critical water surface.

[0004] This application achieves the above effects through the following technical solutions:

[0005] A dynamic tension-torsion test platform for amphibious rotorcraft across media is disclosed. The test platform includes a tension-torsion testing device, a test chamber, a media disturbance device, and a water level regulating device.

[0006] The test chamber includes an open upper space consisting of a frame and a transparent plastic shell;

[0007] The medium disturbance device is installed inside one side of the frame structure;

[0008] The water level regulating device is located at the lower part of the transparent shell on one side of the medium disturbance device;

[0009] The tension-torsion testing device includes a tension-torsion loading structure, which corresponds to the fan blade;

[0010] The medium disturbance device includes a motor and a gear meshing transmission device.

[0011] Furthermore, the medium disturbance device is installed inside the test chamber on one side. The output end of the motor is connected to the gear meshing transmission device, and the output end of the gear meshing transmission device is connected to the fan blade device. The motor is installed on the test chamber of the device by a positioning nut, and the output shaft of the motor is connected to a short shaft. The gear meshing transmission device includes a short shaft, a short shaft gear, a long shaft, and a long shaft gear. The long shaft is connected to the fan blade device, and the short shaft gear is installed on the short shaft and driven to rotate by the short shaft. The long shaft gear meshes with the short shaft gear, and while the long shaft gear is driven by the short shaft gear, it also drives the long shaft to rotate. The long shaft drives the fan blade device to rotate.

[0012] Furthermore, the water level regulating device is located at the lower part of the transparent shell on one side of the medium disturbance device, and the water level regulating device is connected to an external water pipe for injecting or releasing water into the transparent shell.

[0013] Furthermore, the tension-torsion testing device includes a thrust rod, a Y-shaped platform support, and a rotorcraft fixed platform. A strain gauge fixing disk is connected below the rotorcraft fixed platform. Several strain gauges are installed on one side of the strain gauge fixing disk facing the rotorcraft fixed platform, and the other side is connected to the center of the Y-shaped platform support.

[0014] The Y-shaped platform support includes three branches, each of which is equipped with a thrust rod, and the end of the thrust rod is equipped with a push rod.

[0015] Furthermore, three strain gauges are installed on one side of the rotorcraft mounting platform facing the strain gauge fixing disk, and each strain gauge corresponds to a branch of the Y-shaped platform support.

[0016] Furthermore, there are three thrust rods, which are fixed to the bottom of the test box at 120° intervals around the vertical direction of the test platform center.

[0017] This application also provides a tension and torsion test method for the aforementioned amphibious rotorcraft cross-medium dynamic tension and torsion test platform. The tension and torsion of the rotorcraft are calculated using the following formula.

[0018]

[0019]

[0020]

[0021]

[0022] The data in the formula are the data obtained when the centerline of the rotorcraft coincides with the line from the first strain gauge to the midpoint of the rotorcraft's fixed platform. The vertical forces measured by the first, second, and third strain gauges are respectively. R represents the tangential force measured by the first, second, and third strain gauges, and R is the distance from the strain gauge to the midpoint of the rotorcraft's fixed platform.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] 1. The present invention provides a cross-medium tension and torsion testing device based on an amphibious rotorcraft. The testing platform can collect experimental data at different altitudes in one or more media, providing a good reference for the design of rotorcraft.

[0025] 2. The cross-medium tension-torsion testing device based on an amphibious rotorcraft described in this invention uses only three thrust rods and three strain gauges while ensuring the accuracy of experimental data. By decoupling the calculation of experimental data, the structure of the testing platform is greatly simplified, while also ensuring the stability of the testing platform.

[0026] 3. The cross-medium tension and torque testing device based on an amphibious rotorcraft described in this invention adjusts the flight angle of attack of the rotorcraft by advancing three thrust rods at different strokes, which facilitates the collection of tension and torque of the aircraft at different flight angles and different flight media.

[0027] 4. The amphibious rotorcraft test platform described in this invention can freely switch between water and air media, and can be conveniently applied to water and air media and water-air critical states without the need for additional equipment. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the overall structure of the test platform of the present invention;

[0029] In the diagram, 1. Test chamber, 2. Transparent shell, 3. Water level adjustment device, 4. Tension and torsion test device, 5. Medium disturbance rotating device, 6. Gear meshing transmission device;

[0030] Figure 2 This invention relates to a tension-torsion testing device;

[0031] In the diagram, 7. Rotorcraft mounting platform, 8. Y-shaped support, 9. First thrust rod, 10. Second thrust rod, 11. Third thrust rod;

[0032] Figure 3 This invention relates to a medium disturbance device;

[0033] In the diagram, 12. long shaft, 13. fan blade mechanism, 14. long shaft gear;

[0034] Figure 4 This invention relates to a gear meshing transmission device;

[0035] In the diagram, 15. Short shaft gear, 16. Short shaft, 17. Motor;

[0036] Figure 5 This is a partial schematic diagram of the tension-torsion testing device of the present invention;

[0037] In the figure, 18 is the first strain gauge, 19 is the second strain gauge, and 20 is the third strain gauge;

[0038] Figure 6 This is a schematic diagram of the test box and its internal structure according to the present invention. Detailed Implementation

[0039] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings in the embodiments of the present invention.

[0040] Example 1

[0041] As attached Figure 1 As shown, a cross-medium dynamic tension-torsion testing device based on a rotorcraft is disclosed. The testing platform includes a test box 1, a transparent shell 2, a water level adjustment device 3, a tension-torsion testing device 4, a medium disturbance device 5, and a gear meshing transmission device 6. The tension-torsion testing device includes a rotorcraft fixed platform 7, a Y-shaped bracket 8, a first thrust rod 9, a second thrust rod 10, a third thrust rod 11, a first strain gauge 18, a second strain gauge 19, and a third strain gauge 20. The medium disturbance device includes a long shaft 12, a fan-blade mechanism 13, and a long shaft gear 14. The gear meshing device includes a short shaft gear 15, a short shaft 16, and a motor 17. Further, the motor 17 is mounted on the test box 1 via a positioning nut, and the motor's output shaft is connected to a short shaft 16, driving the short shaft to move.

[0042] Furthermore, the test chamber primarily confines the rotorcraft within the platform support structure, enhancing experimental safety. It features a simple and reliable structure, convenient assembly and deformation, and easy observation. Its sides and bottom are enclosed by a transparent plastic shell, facilitating the replacement of experimental media and enhancing observation, thus significantly improving experimental safety.

[0043] Furthermore, the medium disturbance device can use four fan blades to change the flow velocity of the medium in the experimental device to simulate the turbulent water flow and strong winds in rivers and lakes.

[0044] Furthermore, the short-axis gear 15 is mounted on the short-axis 16 and driven by the short-axis 16; the short-axis gear 15 meshes with the long-axis gear 14, driving the long-axis gear 14 to move. Simultaneously, the long-axis gear 14 is connected to the long-axis 12, which is connected to the medium disturbance device 5. The long-axis gear 14 drives the long-axis 12, thus driving the medium disturbance device to move, thereby changing the medium flow state. Furthermore, the first to third thrust rods 9-11 are fixed to the bottom of the test chamber in an isosceles triangle configuration. Their push rods are connected to the Y-shaped bracket 8, and the Y-shaped platform moves up and down with the push rods. Their functions are twofold: first, to support the fixed platform of the rotorcraft 7; and second, to adjust the working altitude of the rotorcraft in the water. When the three thrust rods rise to different heights, the flight angle of the rotorcraft changes. When the thrust rod rises to a certain height and reaches the critical water surface, the thrust and torsional torque of the rotorcraft can be observed to analyze the effects of different flight angles, different heights in the water, and wave drag and ground effect on the rotorcraft during cross-medium flight. Furthermore, the Y-shaped support 8 is mainly used to support the rotorcraft fixing platform 7, ensuring the stability of the test platform and thus ensuring the accuracy of the data obtained. Further, the rotorcraft fixing platform 7 consists of two disc structures connected at the bottom to the Y-shaped support 8. Between the two disc structures are three strain gauges 18-20, measuring the thrust and torque of the rotorcraft in both medium states, thereby analyzing the effects of wave drag and ground effect on the amphibious rotorcraft. The upper disc is fixed to the rotorcraft. Furthermore, the medium disturbance device 5 can use a four-blade mechanism 13 to change the flow velocity of the medium in the experimental device to simulate turbulent water flow and strong winds in rivers and lakes.

[0045] The cross-medium tension-torsion testing device for the rotorcraft involves filling the experimental setup with water to two-thirds full. The rotorcraft is fixed to a rotorcraft mounting platform, with the rotorcraft's central axis coinciding with the line from the first strain gauge to the midpoint of the mounting platform. When testing various data points of the rotorcraft in level flight at different water flow velocities, the three thrust rods precess by the same stroke. The water flow velocity is accelerated by the medium disturbance device, allowing the changes in the three strain gauges to measure the thrust and torsional torque of the rotorcraft during level flight at different water flow velocities. When the three thrust rods bring the rotorcraft to the critical water surface, ocean waves are simulated by the medium disturbance device. By observing the changes in the strain gauge data, the influence of ocean waves on the thrust and torque of the rotorcraft during cross-medium level flight can be obtained, enabling further analysis of the flight state of the amphibious rotorcraft during cross-medium flight.

[0046] The aforementioned cross-medium dynamic tension-torsion test device for rotorcraft is used when the rotorcraft is flying at a certain angle. In the device marked 2 / 3 full, three thrust rods are driven to advance at different strokes, causing the tension-torsion test device to form a certain angle. Simultaneously, a medium disturbance device is activated to change the experimental environment.

[0047] When testing the rotorcraft's pitch flight at a certain altitude, only three thrust rods need to advance a certain distance simultaneously. Once a certain altitude is reached, thrust rod 7 is adjusted to create a specific pitch angle in the tension-torsion testing device. Simultaneously, the medium disturbance device is activated to simulate ocean currents and airflow. The thrust and torsional moments of the rotorcraft during pitch flight under the influence of ocean currents can be measured by observing the changes in the three strain gauges of the tension-torsion testing device. When the three thrust rods bring the rotorcraft to the critical water surface, the experimental data of the rotorcraft's cross-medium pitch flight under the influence of ocean currents and airflow can be obtained by observing the changes in the strain gauge data. This allows for the analysis of the flight state of amphibious rotorcraft during cross-medium pitch flight.

[0048] When testing a rotorcraft's tumbling flight at a certain altitude, only three thrust rods need to advance a certain distance simultaneously. Once a certain altitude is reached, the first or second thrust rod (8 or 9) is adjusted to create a specific tumbling angle in the tension-torsion testing device. Simultaneously, the medium disturbance device is activated, and the tension and torsional torque of the rotorcraft during tumbling flight under different ocean currents and airflows can be measured by observing the changes in the three strain gauges of the tension-torsion testing device. When the three thrust rods bring the rotorcraft to the critical water surface, the experimental data of the rotorcraft during transmedium tumbling flight can be obtained by observing the changes in the strain gauge data. This allows for the analysis of the flight state of amphibious rotorcraft during transmedium tumbling flight.

[0049] Example 2

[0050] This application also provides a tension and torsion test method for the aforementioned amphibious rotorcraft cross-medium dynamic tension and torsion test platform. The tension and torsion of the rotorcraft are calculated using the following formula.

[0051]

[0052]

[0053]

[0054]

[0055] The data in the formula are the data obtained when the centerline of the rotorcraft coincides with the line from the first strain gauge to the midpoint of the rotorcraft's fixed platform. The vertical forces measured by the first, second, and third strain gauges are respectively. R represents the tangential force measured by the first, second, and third strain gauges, and R is the distance from the strain gauge to the midpoint of the rotorcraft's fixed platform.

[0056] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art can make various modifications and adjustments within the technical scope disclosed in the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A cross-medium dynamic tension-torsion test platform for amphibious rotorcraft, characterized in that: The testing platform includes a tensile-torsion testing device, a testing chamber, a media disturbance device, and a water level regulating device; wherein... The test chamber includes an open upper space consisting of a frame and a transparent plastic shell; The medium disturbance device is installed inside one side of the frame structure. The water level regulating device is located at the lower part of the transparent shell on one side of the medium disturbance device; The tension-torsion testing device includes a tension-torsion loading structure, which corresponds to the fan blade; The medium disturbance device includes a motor and a gear meshing transmission device; The medium disturbance device is installed inside the test chamber on one side. The output end of the motor is connected to the gear meshing transmission device, and the output end of the gear meshing transmission device is connected to the fan blade device. The motor is installed on the test chamber of the device by a positioning nut, and the output shaft of the motor is connected to a short shaft. The gear meshing transmission device includes a short shaft, a short shaft gear, a long shaft, and a long shaft gear. The long shaft is connected to the fan blade device, and the short shaft gear is installed on the short shaft and driven to rotate by the short shaft. The long shaft gear meshes with the short shaft gear, and while the long shaft gear is driven by the short shaft gear, it also drives the long shaft to rotate. The long shaft drives the fan blade device to rotate.

2. The amphibious rotorcraft cross-medium dynamic tension-torsion test platform according to claim 1, characterized in that: The water level regulating device is located at the lower part of the transparent shell on one side of the medium disturbance device. The water level regulating device is connected to a water pipe for injecting or releasing water into the transparent shell.

3. The amphibious rotorcraft cross-medium dynamic tension-torsion test platform according to claim 1, characterized in that: The tension-torsion testing device includes a thrust rod, a Y-shaped platform support, and a rotorcraft fixed platform. A strain gauge fixing disk is connected below the rotorcraft fixed platform. Several strain gauges are installed on one side of the strain gauge fixing disk facing the rotorcraft fixed platform, and the other side is connected to the center of the Y-shaped platform support. The Y-shaped platform support includes three branches, each of which is equipped with a thrust rod, and the end of the thrust rod is equipped with a push rod.

4. The amphibious rotorcraft cross-medium dynamic tension-torsion test platform according to claim 3, characterized in that: Three strain gauges are installed on one side of the opposing rotorcraft mounting platform, with each strain gauge corresponding to a branch of the Y-shaped platform support.

5. The amphibious rotorcraft cross-medium dynamic tension-torsion test platform according to claim 3, characterized in that: There are three thrust rods, which are fixed to the bottom of the test box at 120° intervals around the vertical axis of the test platform center.

6. The tension-torsion test method for a cross-medium dynamic tension-torsion test platform for amphibious rotorcraft according to claim 5, characterized in that: The thrust and torque of a rotorcraft are calculated using the following formulas: ； ； ； ； The data in the formula are the data obtained when the centerline of the rotorcraft coincides with the line from the first strain gauge to the midpoint of the rotorcraft's fixed platform. The vertical forces measured by the first, second, and third strain gauges are respectively. R represents the tangential force measured by the first, second, and third strain gauges, and R is the distance from the strain gauge to the midpoint of the rotorcraft's fixed platform.

Images