A high-speed falling body slamming test device and method with controllable angular velocity

Abstract

The present invention belongs to the technical field of structure impact test into water, and discloses a high-speed falling body impact test device and method with controllable angular velocity. The device includes structures such as a guide rail and a slider, a traction device, a speed sensor switch, an angle sensor switch, a rate gyroscope, a laser speed measuring device and a water immersion sensor. The guide rail, the slider and the traction device are used for fixing and releasing, and provide horizontal speed. The laser speed measuring device is used to measure the horizontal speed of the target structure to control the release of the speed sensor switch. The rate gyroscope is used to measure the angular velocity of the target structure to control the release of the angle sensor switch. The water immersion sensor is used to accurately determine the time when the structure falls into water. The present invention has a simple and reliable structure and is easy to operate. It combines the vertical falling motion released by the model to achieve the release of multiple degrees of freedom of the model.

Description

Technical Field

[0001] The present invention belongs to the technical field of structure water impact testing, and in particular relates to a high-speed falling body impact testing device and method with controllable angular velocity. Background Art

[0002] During the launch of underwater equipment, such as unmanned submersibles, slamming loads are a significant concern. This problem is widely applicable in numerous industries, particularly marine and coastal engineering. Solving this problem relies heavily on the shape of the water surface boundary, exhibiting strong nonlinearity, making it extremely complex and difficult to solve analytically. Furthermore, it significantly impacts structural safety. Current research on slamming loads, in addition to theoretical calculations and simulation analysis, relies on model testing as an accurate and intuitive method for studying slamming loads. Furthermore, conducting launch tests requires the use of appropriate drop-body slamming test equipment. The launch process for unmanned equipment is characterized by high speed, meaning a high launch velocity. Furthermore, due to the relatively small size of the underwater equipment used for launch, it is affected by wind and waves during the launch process, resulting in rotational angular velocity.

[0003] Regarding the design of the impact test device, an invention patent for a high-speed water entry impact test device has been disclosed (publication number CN107607292A, publication date 20180119). This device has no guide rails and can only be used for free fall tests of structures. It cannot achieve horizontal high-speed and inclined angular velocity entry of the test model into the water.

[0004] The invention patent discloses a falling body impact test device (publication number CN106556504A, publication date 20170405), which can control the three-dimensional posture of the model, but the guide rail is permanently fixed in a vertical state, and it is impossible to achieve the model's angular velocity of entry into the water and horizontal high-speed entry into the water.

[0005] A patent application for a six-degree-of-freedom water impact test device (publication number CN115042935A, publication date September 13, 2022) discloses a device capable of providing a test model with multi-degree-of-freedom directional velocities. However, this device is incapable of controlling the model's angular velocity or high-speed water entry, and the device is relatively complex. Therefore, a high-speed drop impact test device and method capable of controlling the test model's angular velocity is crucial to address these challenges.

[0006] The above analysis reveals the following problems and drawbacks of the existing technology: Most existing water slamming test rigs fail to account for the horizontal velocity of the test model and lack initial angular velocity. This fails to meet the high-speed water entry requirements for small and medium-sized slamming test models and cannot effectively achieve multi-degree-of-freedom water entry. Summary of the Invention

[0007] To overcome the problems existing in related technologies, the disclosed embodiments of the present invention provide a high-speed drop slamming test apparatus and method with controllable angular velocity. This invention addresses the problem that most existing water slamming test rigs fail to account for the horizontal velocity of the test model and lack an initial angular velocity. The present invention provides a drop slamming test apparatus and method designed to meet the requirements for high-speed water entry for small and medium-sized slamming test models, while also ensuring the test model has the initial angular velocity required for water entry, enabling multi-degree-of-freedom water entry.

[0008] The technical solution is as follows: a high-speed falling body impact test device with controllable angular velocity, the device being fixed on a guide rail, a slider being installed on the guide rail and fixed to a connecting device, a traction device located on the guide rail driving the slider and the connecting device to move horizontally, and the lower part of the connecting device being connected to the test model via a fixing rod;

[0009] A speed sensor switch and an angle sensor switch are respectively provided at the lower ends of the front and rear fixed rods, and the speed sensor switch and the angle sensor switch are respectively controlled by a laser speed measuring device and a rate gyroscope;

[0010] The laser speed measuring device is located at the right end of the guide rail to measure the real-time horizontal speed of the traction device, and the rate gyroscope is located inside the test model to measure the real-time angular velocity of the test model;

[0011] Water immersion sensors are installed at both ends of the test model. When the test model enters the water, the water immersion sensors are triggered to determine the moment of entry of the test model. Combined with the rate gyroscope, the angular velocity of the test model at the moment of entry is obtained.

[0012] The vertical velocity of the test model at the moment of entering the water is calculated by the release height of the test model. After obtaining the horizontal velocity, vertical velocity and angular velocity of the test model at the moment of entering the water, the motion state of the test model relative to the water surface is further calculated by coordinate system transformation combined with the water flow rate.

[0013] Furthermore, the judgment data of the speed sensor switch and the angle sensor switch come from the speed and angular velocity values ​​collected by the laser speed measuring device and the rate gyroscope respectively;

[0014] When the speed sensor detects that the target horizontal speed reaches a certain value, the speed sensor transmits an electrical signal to the speed sensor switch, causing the speed sensor switch to automatically open;

[0015] The angular velocity sensor is controlled according to the target acceleration measured by the rate gyroscope.

[0016] Furthermore, the horizontal speed of the test model is provided by the traction device and is controlled by a laser speed measuring device and a speed sensor switch. The angular speed is provided by the time-delayed release of two fixed rods and is controlled by a rate gyroscope and an angle sensor switch.

[0017] Furthermore, the test model is a slender structure.

[0018] Another object of the present invention is to provide a high-speed drop slamming test method with controllable angular velocity, which is run on the high-speed drop slamming test device with controllable angular velocity, and comprises:

[0019] S1, the traction device drives the slider and the test model connected to it through the rope, and the traction device makes the test model obtain horizontal speed;

[0020] S2, when the horizontal speed reaches the target value, the horizontal speed is measured by the laser speed measuring device as v i , the speed sensor transmits an electrical signal to the speed sensor switch, the speed sensor switch opens, and the speed sensor switch releases so that the test model starts to rotate;

[0021] S3: When the test model's rotational angular velocity reaches the target value, its angular velocity is measured by the rate gyroscope as ω. At this time, the angle sensor switch is released, and the release time is recorded as t1. The test model has the initial release horizontal velocity and angular velocity, and falls downward under the action of gravity.

[0022] In step S3, the drop height is set to h. When the test model hits the water, the water sensor arranged at the end of the test model hits the water and generates an electrical signal, thereby determining the time of entry into the water t2. The vertical velocity v′ of the test model at the moment of entry into the water is calculated by the following formula: j ;

[0023] v′ j =g(t1-t2)

[0024] Where g is the acceleration due to gravity.

[0025] In step S3, the angular velocity ω′ of the test model at the moment of entering the water is determined by the water immersion sensor and the rate gyroscope, combined with the wave velocity v w The horizontal velocity v′ of the test model relative to the wave surface at the moment of entry into the water is calculated by the following formula through coordinate system transformation: i ;

[0026] v′ i =v i -v w

[0027] Where, v i is the initial release horizontal velocity of the test model

[0028] Furthermore, the high-speed falling body slamming test method with controllable angular velocity is applied to the slamming load test of underwater equipment of unmanned submersibles during the water launch process.

[0029] Furthermore, the high-speed drop impact test method with controllable angular velocity is installed on a computer device, which includes: at least one processor, a memory, and a computer program stored in the memory and executable on the at least one processor. When the processor executes the computer program, the steps in the high-speed drop impact test method with controllable angular velocity described above are implemented.

[0030] Furthermore, the high-speed drop impact test method with controllable angular velocity is carried on a computer-readable storage medium, and the computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the steps in the high-speed drop impact test method with controllable angular velocity described above can be implemented.

[0031] Combining all the above technical solutions, the beneficial effects of the present invention are as follows: the present invention solves the problem of rotating high-speed water entry slamming tests on small and medium-sized models in drop slamming tests. It includes structures such as guide rails and sliders, a traction device, a speed sensor switch, an angle sensor switch, a rate gyroscope, a laser speed measuring device, and a water immersion sensor. The guide rails, sliders, and traction device are used for fixing and releasing, and provide horizontal speed. The laser speed measuring device is used to measure the horizontal speed of the target structure to control the release of the speed sensor switch. The rate gyroscope is used to measure the angular velocity of the target structure to control the release of the angle sensor switch. The water immersion sensor is used to accurately determine the time when the structure falls into the water. The present invention achieves precise control of the horizontal velocity and angular velocity of the model at the moment of release through the asynchronous release of the front and rear switches. It has a simple and reliable structure and is easy to operate. Combined with the vertical falling motion of the model release, it can achieve the release of multiple degrees of freedom of the model.

[0032] The present invention provides a new approach for the horizontal and vertical high-speed drop slam release method for drop slam tests; the present invention solves the problem of being unable to achieve structural rotation into water during high-speed drop slam tests; the present invention provides a new method for drop slam tests, achieving multi-degree-of-freedom drop slam with controllable angular velocity. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure;

[0034] Figure 1 1. It is a schematic structural diagram of a high-speed falling body impact test device with controllable angular velocity provided by the present invention;

[0035] Figure 2 2. It is a side view of the high-speed falling body slamming test device with controllable angular velocity provided by the present invention;

[0036] Figure 3It is a horizontal motion timing diagram of the test model provided by the present invention;

[0037] Figure 4 This is a diagram showing the release time of the speed sensor switch after the horizontal speed of the test model provided by the present invention reaches the target value;

[0038] Figure 5 This is a diagram showing the release time of the angle sensor switch after the angular velocity of the test model provided by the present invention reaches the target value;

[0039] Figure 6 This is a diagram of the water entry timing of the test model provided by the present invention;

[0040] In the figure: 1. Guide rail; 2. Slider; 3. Traction device; 4. Laser speed measuring device; 5. Test model; 6. Angle sensor switch; 7. Speed ​​sensor switch; 8. Rate gyroscope; 9. Connecting device; 10. Fixing rod; 11. Rope; 12. Water immersion sensor. DETAILED DESCRIPTION

[0041] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0042] The innovative features of the high-speed drop impact test device and method with controllable angular velocity provided by the embodiments of the present invention are: the use of the guide rail 1 combined with the release method of the traction device 3 to achieve horizontal and vertical high-speed release of the structure, the differential release of the structure controlled by the sensor to give the structure an initial angular velocity, and the accurate determination of the motion state of the structure at the moment of water impact by the water immersion sensor 12.

[0043] Example 1, as Figure 1-Figure 2 As shown, an embodiment of the present invention provides a high-speed falling body impact test device with controllable angular velocity, including a guide rail 1, a slider 2, a traction device 3, a laser speed measuring device 4, a test model 5, an angle sensor switch 6, a speed sensor switch 7, a rate gyroscope 8, a connecting device 9, a fixing rod 10, a rope 11 and a water immersion sensor 12.

[0044] The main structure of the high-speed falling body slamming test device with controllable angular velocity is fixed on the guide rail 1;

[0045] The slider 2 is fixed on the guide rail 1 and fixed to the connecting device 9. The traction device 3 located on the guide rail 1 drives the slider 2 and the connecting device 9 to move horizontally at high speed. The connecting device 9 is connected to the test model 5 through a fixed rod 10 at the bottom.

[0046] A speed sensor switch 7 and an angle sensor switch 6 are respectively provided at the ends of the front and rear fixed rods 10. The speed sensor switch 7 and the angle sensor switch 6 are respectively controlled by the laser speed measuring device 4 and the rate gyroscope 8. The judgment data of the speed sensor switch 7 and the angle sensor switch 6 are respectively derived from the speed or angular velocity values ​​collected by the laser speed measuring device 4 and the rate gyroscope 8.

[0047] When the speed sensor detects that the target horizontal speed reaches a certain value, the speed sensor will transmit an electrical signal to the speed sensor switch 7, so that the speed sensor switch 7 will automatically open to achieve precise control.

[0048] Specifically, a laser speed measuring device 4 is located at the right end of the guide rail 1 to measure the real-time horizontal speed of the traction device 3. A rate gyroscope 8 is located inside the test model 5 to measure the real-time angular velocity of the test model 5. The angular velocity sensor is controlled by an algorithm based on the target acceleration measured by the rate gyroscope 8.

[0049] Specifically, the horizontal speed of the test model 5 is provided by the traction device 3 and is controlled by the laser speed measuring device 4 and the speed sensor switch 7. The angular velocity is provided by the time-delayed release of the two fixed rods 10 and is controlled by the rate gyroscope 8 and the angle sensor switch 6.

[0050] In addition, under the premise that the test model 5 is a slender structure, water immersion sensors 12 are provided at both ends of the test model 5. When the test model 5 enters the water, the water immersion sensors 12 are triggered, thereby accurately determining the moment when the test model 5 enters the water. Combined with the rate gyroscope 8, the angular velocity of the test model 5 at the moment of entry into the water can be accurately obtained.

[0051] In addition to obtaining the horizontal velocity and angular velocity of the test model 5 at the time of release and entry into the water, the vertical velocity of the test model 5 at the time of entry into the water can also be calculated through the release height of the test model 5. After obtaining the horizontal velocity, vertical velocity, and angular velocity of the test model 5 at the time of entry into the water, the motion state of the test model 5 relative to the water surface can be further calculated through coordinate system conversion combined with the water flow rate.

[0052] The operating process of the device of the present invention is as follows: The test frame body is fixed to the guide rail 1 structure. The test model 5 is fixed to the bottom of the fixed rod 10 and set at an appropriate release height. The traction device 3 is connected to the slider 2 to ensure speed transmission. The sensitivity of the laser speed measuring device 4, the rate gyroscope 8, and the corresponding sensors are adjusted. The traction device 3 is activated, driving the test model 5 in horizontal motion. As the horizontal speed of the test model 5 increases until it reaches the preset value of the test speed sensor, the speed sensor switch 7 is released, and the test model 5 begins to rotate around the angle sensor switch 6. When the rotational angular velocity reaches the preset value of the test angular velocity sensor, the angle sensor switch 6 is released, and the test model 5 begins to fall while maintaining the preset test horizontal and angular velocities until it impacts the water. The fluctuation of the electrical signal from the water immersion sensor 12 can accurately determine the time when the test model 5 enters the water. The angular velocity of the test model 5 entering the water, the horizontal velocity relative to the wave surface, and the vertical velocity of the test model 5 can be calculated using known relevant formulas.

[0053] In Example 2, the high-speed falling body impact test method with controllable angular velocity provided by the embodiment of the present invention is firstly driven by the traction device 3 through the rope 11 to drive the slider 2 and the test model 5 connected thereto to move, as shown in FIG. Figure 3 As shown, the test model 5 can obtain a higher horizontal speed by changing the rotation speed of the motor in the traction device 3, wherein the process of changing the motor rotation speed is realized by a microcontroller connected to the motor.

[0054] The laser speed measuring device 4 will monitor the horizontal speed of the test model 5 in real time and transmit the data to the microcontroller. i When (as can be seen from the electrical signal released by the speed sensor), the microcontroller will send an electrical signal to the motor, and the motor will then turn on the speed sensor switch 7, as shown in FIG. Figure 4 As shown, the speed sensor switch 7 is released, causing the test model 5 to start rotating.

[0055] When the rotation angular velocity of the test model 5 reaches the target value, the angular velocity is measured by the rate gyroscope 8 as ω. At this time, the angle sensor switch 6 is released, and the release time is recorded as t1. Figure 5 As shown, the test model 5 has an initial release horizontal velocity and angular velocity, and falls downward under the action of gravity.

[0056] Assume that the drop height is h, and the test model 5 is about to hit the water. Figure 6 As shown, Figure 4-Figure 6 In, v i represents the initial release horizontal velocity of the test model; ω represents the initial release angular velocity of the test model; v j represents the vertical velocity of the test model; v′ jrepresents the vertical velocity of the test model at the time of entry into the water; ω′ represents the angular velocity of the test model at the time of entry into the water; v′ i represents the horizontal velocity of the test model relative to the wave surface when it enters the water; v w Indicates the velocity of the wave.

[0057] At this time, the water immersion sensor 12 arranged at the end of the test model 5 touches the water and generates an electrical signal, thereby determining the time of entry into the water t2. The vertical velocity v' of the test model 5 at the time of entry into the water can be calculated by the following known formula: j , where g represents the acceleration due to gravity:

[0058] v′ j =g(t1-t2)

[0059] The angular velocity ω′ of the test model 5 at the moment of entering the water can be accurately determined by the rate gyroscope 8 through the water immersion sensor 12 contact time, and then combined with the wave velocity v w The horizontal velocity v′ of the test model 5 relative to the wave surface at the moment of entry into the water is calculated by coordinate system transformation according to the following known formula: i :

[0060] v′ i =v i -v w

[0061] It can be seen from the above embodiments that the method of the present invention is easy to operate and has a simple structure. It can control the horizontal high-speed entry of the test model into the water, and can also control the initial release angular velocity of the test model and accurately judge the entry time and angular velocity at the time of entry, thereby meeting the operational requirements of the launch.

[0062] The above description is only a preferred specific implementation method of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with this technical field within the technical scope disclosed by the present invention and within the spirit and principles of the present invention should be covered by the scope of protection of the present invention.

Claims

1. A high-speed falling body impact test device with controllable angular velocity, characterized in that: The device is fixed on a guide rail (1), a slider (2) is installed on the guide rail (1), and is fixed to a connecting device (9), a traction device (3) located on the guide rail (1) drives the slider (2) and the connecting device (9) to move horizontally, and the lower part of the connecting device (9) is connected to the test model (5) through a fixing rod (10); A speed sensor switch (7) and an angle sensor switch (6) are respectively provided at the lower ends of the front and rear fixing rods (10), and the speed sensor switch (7) and the angle sensor switch (6) are respectively controlled by a laser speed measuring device (4) and a rate gyroscope (8); The laser speed measuring device (4) is located at the right end of the guide rail (1) and is used to measure the real-time horizontal speed of the traction device (3). The rate gyroscope (8) is located inside the test model (5) and is used to measure the real-time angular speed of the test model (5). Water immersion sensors (12) are provided at both ends of the test model (5). When the test model (5) enters the water, the water immersion sensors (12) are triggered to determine the moment when the test model (5) enters the water. The angular velocity of the test model (5) at the moment of entering the water is obtained by combining with the rate gyroscope (8). The vertical velocity of the test model (5) at the moment of entering the water is calculated by the release height of the test model (5). After obtaining the horizontal velocity, vertical velocity and angular velocity of the test model (5) at the moment of entering the water, the motion state of the test model (5) relative to the water surface is further calculated by combining the coordinate system conversion with the water flow rate; The judgment data of the speed sensor switch (7) and the angle sensor switch (6) are respectively from the speed and angular velocity values ​​collected by the laser speed measuring device (4) and the rate gyroscope (8); When the speed sensor detects that the target horizontal speed reaches a certain value, the speed sensor transmits an electrical signal to the speed sensor switch (7), thereby automatically opening the speed sensor switch (7); controlling the angle sensor switch (6) according to the target acceleration measured by the rate gyroscope (8); The horizontal speed of the test model (5) is provided by the traction device (3) and is controlled by the laser speed measuring device (4) and the speed sensor switch (7). The angular speed is provided by the time difference release of two fixed rods (10) and is controlled by the rate gyroscope (8) and the angle sensor switch (6).

2. The high-speed falling body slamming test device with controllable angular velocity according to claim 1, characterized in that: The test model (5) is a slender structure.

3. A high-speed falling body slamming test method with controllable angular velocity, characterized in that: The method is operated on the high-speed falling body slamming test device with controllable angular velocity according to any one of claims 1-2, and the method comprises: S1, the traction device (3) drives the slider (2) and the test model (5) connected thereto to move through the rope (11), and the traction device (3) causes the test model (5) to obtain a horizontal speed; S2, when the horizontal speed reaches the target value, the horizontal speed is measured by the laser speed measuring device (4) , the speed sensor transmits an electrical signal to the speed sensor switch (7), the speed sensor switch (7) is turned on, and the speed sensor switch (7) is released so that the test model (5) starts to rotate; S3, when the rotation angular velocity of the test model (5) reaches the target value, the angular velocity measured by the rate gyroscope (8) is At this time, the angle sensor switch (6) is released, and the release time is recorded as , the test model (5) has an initial release horizontal velocity and angular velocity, and falls downward under the action of gravity.

4. The high-speed falling body slamming test method with controllable angular velocity according to claim 3, characterized in that: In step S3, the falling height is set to The test model (5) is hit by water, and the water immersion sensor (12) arranged at the end of the test model (5) generates an electrical signal when it touches the water, thereby determining the time of entry into the water. The vertical velocity of the test model (5) at the moment of entering the water is calculated by the following formula: ; ； Where, is the acceleration due to gravity.

5. The high-speed falling body slamming test method with controllable angular velocity according to claim 3, characterized in that: In step S3, the angular velocity of the test model (5) at the moment of entering the water is determined by the water immersion sensor (12) and the rate gyroscope (8). , combined with the wave velocity The horizontal velocity of the test model (5) relative to the wave surface at the moment of entry into the water is calculated by the following formula through coordinate system transformation: ; ； Where, is the initial release horizontal velocity of the test model (5).

6. The high-speed falling body slamming test method with controllable angular velocity according to claim 3, characterized in that: The high-speed falling body slamming test method with controllable angular velocity is applied to the slamming load test of underwater equipment of an unmanned submersible during its launching into water.

7. The high-speed falling body slamming test method with controllable angular velocity according to claim 3, characterized in that: The high-speed drop slamming test method with controllable angular velocity is installed on a computer device, which includes: at least one processor, a memory, and a computer program stored in the memory and executable on the at least one processor. When the processor executes the computer program, the steps of the high-speed drop slamming test method with controllable angular velocity are implemented.

8. The high-speed falling body slamming test method with controllable angular velocity according to claim 3, characterized in that: The high-speed drop impact test method with controllable angular velocity is carried on a computer-readable storage medium, and the computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the steps in the high-speed drop impact test method with controllable angular velocity described above can be implemented.

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