High-speed falling body slamming test device and method capable of controlling angular velocity

Abstract

The invention belongs to the technical field of a structure water entry slamming test, and discloses a high-speed falling body slamming test device and method capable of controlling the angular speed. The device comprises a guide rail, a sliding block, a traction device, a speed sensor switch, an angle sensor switch, a rate gyroscope, a laser speed measuring device, a water sensor and the like. The guide rail, the sliding block and the traction device are used for fixing and releasing and providing horizontal speed, the laser speed measuring device is used for measuring the horizontal speed of a target structure so as to control releasing of the speed sensor switch, and the rate gyroscope is used for measuring the angular speed of the target structure so as to control releasing of the angle sensor switch. And the water sensor is used for accurately judging the water entry time of the falling body slamming of the structure. The device is simple and reliable in structure and easy and convenient to operate, and multi-degree-of-freedom release of the model is achieved by combining the vertical falling motion of model release.

Description

Technical Field

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

[0002] During the launching process of underwater equipment such as unmanned submersibles, the impact load cannot be ignored. The impact problem is widely used in many industries, especially in marine and coastal engineering. The solution to the water entry problem depends largely on the change of the shape of the water surface boundary, which has a strong nonlinearity, making the problem extremely complex and difficult to solve analytically. At the same time, it has an important impact on the safety of the structure. In addition to theoretical calculations and simulation analysis, model tests are still an accurate and intuitive method for studying impact loads. For the current research on impact loads, a corresponding drop impact test device must be available for the water entry test. The water entry process of unmanned equipment has the characteristics of high speed, that is, the launch speed is high. In addition, due to the small size of the underwater equipment used for launching, it will be affected by wind and waves during the launch process and have a 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). The 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 the angular velocity of the model entering the water and the horizontal high-speed entry into the water cannot be achieved.

[0005] The invention patent discloses a water impact test device for six-degree-of-freedom motion of a structure (publication number CN115042935A, publication date 20220913), which publicly realizes the function of enabling the test model to have multi-degree-of-freedom directional speed, but cannot realize the model's rotational angular velocity and high-speed water entry, and the device is relatively complex. Therefore, it is very necessary to design a high-speed falling body impact test device and test method that can control the angular velocity of the test model to solve the above problems.

[0006] Through the above analysis, the problems and defects of the existing technology are as follows: most of the existing water entry impact test frames cannot consider the horizontal velocity of the test model, and none of them have the problem of initial angular velocity. They cannot meet the requirements of high-speed water entry of small and medium-sized impact test models, and cannot effectively achieve multi-degree-of-freedom water entry. Summary of the invention

[0007] In order to overcome the problems existing in the related art, the disclosed embodiments of the present invention provide a high-speed falling body slamming test device and method with controllable angular velocity. Aiming at the problem that most existing water entry slamming test frames cannot consider the horizontal velocity of the test model and do not have the initial angular velocity, the present invention provides a falling body slamming test device and method, the purpose of which is to meet the requirements of high-speed water entry of small and medium-sized slamming test models, and to enable the test model to have the water entry conditions with the initial angular velocity, so as to achieve 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 is fixed on a guide rail, a slider is installed on the guide rail and is fixed to a connecting device, a traction device located on the guide rail drives the slider and the connecting device to move horizontally, and the lower part of the connecting device is connected to the test model through a fixing rod;

[0009] A speed sensor switch and an angle sensor switch are respectively arranged at the lower ends of the front and rear fixing 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 set at both ends of the test model. When the test model enters the water, the water immersion sensors are triggered to determine the time when the test model enters the water. Combined with the rate gyroscope, the angular velocity of the test model at the time of entering the water 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 combining the coordinate system conversion with the water flow rate.

[0013] Further, 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, so that the speed sensor switch automatically opens;

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

[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, and 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 falling body slamming test method with controllable angular velocity, which is run on the high-speed falling body slamming test device with controllable angular velocity, and the method comprises:

[0019] S1, the traction device drives the slider and the test model connected to it to move through the rope, and the traction device makes the test model obtain a 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 is turned on, and the speed sensor switch is released so that the test model starts to rotate;

[0021] S3, when the rotation angular velocity of the test model 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, and the test model is hit by water. The water immersion sensor arranged at the end of the test model touches the water and generates an electrical signal, thereby determining the water entry time t2. The vertical velocity v′ of the test model at the moment of water entry 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 time 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 time of entering the water is calculated by the following formula through coordinate system conversion: i ;

[0026] v′ i =v i -v w

[0027] In the formula, 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 process of being dropped into water.

[0029] Furthermore, the high-speed falling body 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, and the processor implements the steps in the high-speed falling body slamming test method with controllable angular velocity when executing the computer program.

[0030] Furthermore, the high-speed falling object 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 falling object impact test method with controllable angular velocity can be implemented.

[0031] Combined with 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 test of small and medium-sized models in falling body slamming test. It includes structures such as guide rails and sliders, traction devices, speed sensor switches, angle sensor switches, rate gyroscopes, laser speed measuring devices and water immersion sensors. The guide rails, sliders and traction devices 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 of entry into water of the falling body slamming of the structure. The present invention realizes precise control of the horizontal speed and angular velocity of the model at the moment of release through the asynchronous release of the front and rear switches. The structure is simple and reliable, and the operation is simple. Combined with the vertical falling motion of the model release, the release of multiple degrees of freedom of the model is realized.

[0032] The present invention provides a new approach for the horizontal and vertical high-speed falling body slamming release method of the falling body slamming test; the present invention solves the problem that the structure cannot be rotated into water in the high-speed falling body slamming test; the present invention provides a new method for the falling body slamming test, realizing the multi-degree-of-freedom falling body slamming with controllable angular velocity; BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings herein are incorporated in and constitute a part of the 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 It is a structural schematic diagram of a high-speed falling body impact test device with controllable angular velocity provided by the present invention;

[0035] Figure 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 It 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 It 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 It is a water entry timing diagram 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] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific implementation disclosed below.

[0042] The innovative point of the high-speed falling body impact test device and method with controllable angular velocity provided by the embodiments of the present invention is that the guide rail 1 is combined with the release method of the traction device 3 to realize the horizontal and vertical high-speed release of the structure, and the differential release of the structure is controlled by the sensor so that the structure has an initial angular velocity. In addition, the water immersion sensor 12 is used to accurately judge the movement state of the structure when it hits the water.

[0043] Embodiment 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 lower part of the connecting device 9 is connected to the test model 5 through a fixing rod 10.

[0046] A speed sensor switch 7 and an angle sensor switch 6 are respectively arranged at the ends of the front and rear fixed rods 10, and 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 come from the speed or angular velocity values ​​collected by the laser speed measuring device 4 and the rate gyroscope 8 respectively;

[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, the 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, and the rate gyroscope 8 is located inside the test model 5 to measure the real-time angular velocity of the test model 5. According to the target acceleration measured by the rate gyroscope 8, the angular velocity sensor is controlled by algorithm conversion.

[0049] Specifically, the horizontal speed of the test model 5 is provided by the traction device 3, and the magnitude is controlled by the laser speed measuring device 4 and the speed sensor switch 7, and the angular velocity is provided by the time-difference release of the two fixed rods 10, and the magnitude 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. The function of the water immersion sensors 12 is to trigger the water immersion sensors 12 when the test model 5 enters the water, thereby accurately judging 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 entering 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 working process of the device of the present invention is as follows: the main body of the test frame is fixed on the guide rail 1 structure, the test model 5 is fixed at the bottom of the fixed rod 10 and set at a suitable release height, the traction device 3 is connected to the slider 2 to ensure the transmission of speed, and the sensitivity of the laser speed measuring device 4 and the rate gyroscope 8 and the corresponding sensors are debugged. The traction device 3 is started to drive the test model 5 to move horizontally. 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 rotation 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 maintain the preset test horizontal speed and angular velocity to fall until it hits the water. The entry time of the test model 5 can be accurately judged by the fluctuation of the electrical signal of the water immersion sensor 12, so that the entry angular velocity of the test model 5, the entry horizontal velocity relative to the wave surface and the vertical velocity are calculated by the known relevant formulas.

[0053] Embodiment 2, the high-speed falling body impact test method with controllable angular velocity provided by the embodiment of the present invention firstly drives the slider 2 and the test model 5 connected thereto to move through the rope 11 by the traction device 3, such as 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 (through the electrical signal collection 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, such as Figure 4 As shown, the speed sensor switch 7 is released, so that the test model 5 starts to rotate.

[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] Assuming the drop height is h, 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 when it enters the water; ω′ represents the angular velocity of the test model when it enters the water; v′ i v represents the horizontal velocity of the test model relative to the wave surface when it enters the water; 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 to generate an electrical signal, thereby determining the water entry time t2. The vertical speed v′ of the test model 5 at the time of entering 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 water contact time of the water immersion sensor 12 can be accurately determined by the rate gyroscope 8 at the moment when the test model 5 enters the water, 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 time of entering the water is calculated by coordinate system conversion 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 the 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 manner of the present invention, but the protection scope of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principles of the present invention should be covered within the protection scope 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) via a fixing rod (10); A speed sensor switch (7) and an angle sensor switch (6) are respectively arranged at the lower ends of the front and rear fixed rods (10); 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 arranged 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 the horizontal velocity, vertical velocity and angular velocity of the test model (5) at the moment of entering the water are obtained, the motion state of the test model (5) relative to the water surface is further calculated by coordinate system conversion combined with the water flow rate.

2. The high-speed falling body impact test device with controllable angular velocity according to claim 1, characterized in that: 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 causing the speed sensor switch (7) to automatically open; The angular velocity sensor is controlled according to the target acceleration measured by the rate gyro (8).

3. The high-speed falling body impact test device with controllable angular velocity according to claim 1, characterized in that: The horizontal speed of the test model (5) is provided by the traction device (3), and its magnitude is controlled by the laser speed measuring device (4) and the speed sensor switch (7); the angular speed is provided by the time-delayed release of two fixed rods (10), and its magnitude is controlled by the rate gyroscope (8) and the angle sensor switch (6).

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

5. A high-speed falling body impact test method with controllable angular velocity, characterized in that: The method is run on the high-speed falling body slamming test device with controllable angular velocity according to any one of claims 1 to 4, and the method comprises: S1, the traction device (3) drives the slider (2) and the test model (5) connected thereto to move via 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) as v i , 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 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. The test model (5) has an initial release horizontal velocity and angular velocity, and falls downward under the action of gravity.

6. The high-speed falling body slamming test method with controllable angular velocity according to claim 5, characterized in that: In step S3, the falling height is set as h, the test model (5) hits the water, and the water immersion sensor (12) arranged at the end of the test model (5) hits the water to generate an electrical signal, thereby determining the water entry time t2, and the vertical speed v of the test model (5) at the time of entering the water is calculated by the following formula: j ′ ; v j ′ =g(t1-t2) Where g is the acceleration due to gravity.

7. The high-speed falling body slamming test method with controllable angular velocity according to claim 5, characterized in that: In step S3, the angular velocity ω of the test model (5) at the time of entering the water is determined by the water immersion sensor (12) and the rate gyroscope (8). ′ , 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 entering the water is calculated by the following formula through coordinate system conversion: i ′ ; v i ′ =v i -v w In the formula, v i is the initial release horizontal velocity of the test model (5).

8. The high-speed falling body slamming test method with controllable angular velocity according to claim 5, 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 unmanned submersibles during the process of being dropped into water.

9. The high-speed falling body slamming test method with controllable angular velocity according to claim 5, characterized in that: The high-speed falling body slamming test method with controllable angular velocity is carried 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 falling body slamming test method with controllable angular velocity are implemented.

10. The high-speed falling body slamming test method with controllable angular velocity according to claim 5, characterized in that: The high-speed falling body slamming 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 falling body slamming test method with controllable angular velocity can be implemented.

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