Device and method for monitoring dynamic deformation of structure under collision load

Abstract

The present invention discloses a device for monitoring the dynamic deformation of a structure under a collision load. The impacted structure undergoes dynamic deformation under the impact load of the impact head. A three-dimensional deformation needle engraving and re-engraving system is located behind the impacted structure and includes a push rod, a support frame, and a transparent baffle. The push rod is arranged between the impacted structure and the transparent baffle and is horizontally constrained on the support frame. The front end of the push rod is in conformal contact with the impacted structure, and the rear end is coated with a fluorescent material and is adjacent to the transparent baffle but not in contact. Both the push rod and the transparent baffle can move freely horizontally. A laser displacement measurement system and a high-speed camera are both arranged behind the transparent baffle. The present invention converts the complex deformation pattern of the hull structure under the impact load into a translational displacement of the transparent baffle in real time through multiple push rods that can move in a single degree of freedom, and monitors the maximum deformation in real time through a laser displacement sensor. The position and time of each fluorescent contact mark on the transparent baffle are recorded by a high-speed camera to determine the movement trajectory of the collision point.

Description

Technical Field

[0001] The present invention relates to the technical field of ship collision experiments, and in particular to a device and method for monitoring dynamic deformation of a structure under collision load. Background Art

[0002] Plates are the most fundamental building blocks of ship hulls and various hydraulic structures. When subjected to ship collision loads, the plate's dynamic response is crucial to overall safety. When localized collision loads act on a structure, while overall deformation (or vibration) may be minimal, the loaded localized area will quickly enter plasticity. Therefore, when studying ship collision issues, the localized response of the structure should be prioritized.

[0003] Measuring the dynamic response of plates is one of the most important areas of experimental mechanics and structural health monitoring. The dynamic response of plates subjected to transverse impact is primarily manifested as out-of-plane displacement (deflection). Currently, the two main methods for measuring dynamic out-of-plane displacement are laser displacement technology and digital image correlation (DIC). Laser displacement technology tends to measure strain in fixed directions at specific points and cannot achieve full-area measurement. DIC has a wide measurement range, but the device is relatively complex and bulky, resulting in stringent application requirements and making it less suitable for small spaces. Therefore, existing measurement methods struggle to accurately, efficiently, and cost-effectively achieve the high-precision measurement requirements for large-scale model experimental structures. Furthermore, factors such as the small size of the ship model, the random location of the initial impact point, the complex hull structure and curved surfaces, the diverse punch types, and the relative slip between objects in ship collision model experiments make it difficult to guarantee the accuracy and precision of dynamic deformation measurements during experiments. Therefore, designing a superior collision dynamic deformation monitoring device to investigate the mechanical mechanisms of plastic deformation of hull structures after collision, with a view to practical engineering applications, is an urgent task. Summary of the Invention

[0004] The main purpose of the present invention is to provide a device and method for monitoring the dynamic deformation of structures under collision loads. The device converts the complex deformation pattern of the hull structure produced by the collision load into the translational displacement of the transparent baffle in real time through multiple push rods that can move in a single degree of freedom, so that a laser displacement sensor at a certain parallel distance from the transparent baffle can monitor the maximum deformation in real time. At the same time, a fluorescent substance that can be identified by a high-speed camera is coated on the rear end of the push rod, and the position and time of each fluorescent contact mark on the transparent baffle are recorded by the high-speed camera, so that the movement trajectory of the collision point can be determined.

[0005] The technical solution adopted in the present invention is:

[0006] A device for monitoring the dynamic deformation of a structure under a collision load comprises an experimental base and a collided system mounted on the experimental base, a three-dimensional deformation needle engraving system, a laser displacement measurement system and a high-speed camera; the collided system is fixed on the experimental base and comprises a collided structure, and the collided structure undergoes dynamic deformation under the action of the collision load at a random position of the collision head; the three-dimensional deformation needle engraving system is located behind the collided structure and is used to visualize the deformation process of the collided structure; the three-dimensional deformation needle engraving system comprises a push rod, a support frame and a transparent baffle, and the push rod is arranged between the collided structure and the transparent baffle to ensure the collision of the collided structure. The laser displacement measurement system and the high-speed camera are arranged horizontally and constrained on the support frame in a matrix shape. The front end of the push rod is in conformal contact with the collided structure, and the rear end of the push rod is coated with fluorescent material and is adjacent to but not in contact with the transparent baffle. Both the push rod and the transparent baffle can move freely in the horizontal direction. The laser displacement measurement system and the high-speed camera are both arranged behind the transparent baffle. The laser displacement measurement system obtains the time history curve of the maximum deformation of the structure during the collision test by measuring the movement distance of the transparent baffle in real time. The high-speed camera determines the movement trajectory of the collision point by capturing the position and time of each fluorescent contact mark on the transparent baffle during the collision.

[0007] In the above scheme, the three-dimensional deformation needle carving and re-engraving system also includes a close spring with its two ends respectively connected to the collided structure and the transparent baffle. The close spring remains in an untensioned state before the start of the test. When the collided structure elastically rebounds, the transparent baffle can be pulled back to achieve continuous contact between the collided structure, the top rod and the transparent baffle, ensuring that the deformation of the collided structure and the movement of the transparent baffle are always consistent, so as to monitor the elastic rebound of the collided structure after the collision.

[0008] In the above scheme, the three-dimensional deformable needle engraving system also includes eye screws and a magnetic base. The eye screws are fixed to the four corners of the transparent baffle, and the magnetic base is installed at the four corners of the impacted structure and arranged one by one opposite to the eye screws. Each group of eye screws and the magnetic base are connected by a tight spring.

[0009] In the above scheme, the three-dimensional deformation needle carving and re-engraving system also includes a baffle bracket, which is located behind the transparent baffle and includes a telescopic rod, a horizontal smooth strut and a strut clamp. The telescopic rod is vertically arranged and fixed on the experimental base, and one end of the horizontal smooth strut is fixed in the strut clamp, and the strut clamp can be slid up and down along the telescopic rod; the other end of the horizontal smooth strut passes through the transparent baffle to realize the installation of the transparent baffle.

[0010] In the above solution, the laser displacement measurement system and the high-speed camera are connected to the data acquisition instrument and the data processing terminal respectively through wires.

[0011] In the above scheme, the length of the top rod is adjusted according to the shape and style of the hit structure to ensure that the front end of the top rod contacts the hit structure and the rear end contacts the transparent baffle; the number of top rods is adjusted according to the size of the hit structure to ensure that the monitoring range of the top rod covers all areas of the hit structure that may be deformed.

[0012] In the above scheme, the push rod includes a spherical rod cap, a conical rod cap and a push pin. The spherical rod cap and the conical rod cap are respectively tightly buckled at the two ends of the push pin. The spherical rod cap is close to the impacted structure in the front, and the conical rod cap is close to the transparent baffle in the rear, and the conical rod cap is coated with fluorescent material.

[0013] In the above scheme, the struck system also includes a tooling foundation and a fixture. The struck structure is fixed to the tooling foundation by bolts around the fixture to form a rigid fixed boundary condition of the actual ship. The tooling foundation is fixed to the experimental base by bolts.

[0014] Accordingly, the present invention further proposes a method for monitoring the dynamic deformation of a structure under a collision load, which uses the above-mentioned device for monitoring the dynamic deformation of a structure under a collision load, comprising:

[0015] S1. Install the structural dynamic deformation monitoring device under the collision load according to the design requirements;

[0016] S2. Turn on the laser emission device and data display screen of the laser displacement measurement system, and simultaneously turn on the high-speed camera; control the impact head to impact the impacted structure at any designed angle and position, then measure the impact depth of the impacted structure during the collision using the laser displacement measurement system, and simultaneously record the contact position between the impact head and the impacted structure using the high-speed camera;

[0017] S3. After the collision experiment is completed, turn off the laser emission device of the laser displacement measurement system and turn off the high-speed camera;

[0018] S4. Remove the springs and record the final scale of each push rod relative to the support frame near the area where the impacted structure deforms. Then subtract the initial scales recorded previously to obtain the final deformation size near the impact area. Subsequently, use 3D software to draw the final deformation curves at different cross-sections of the impacted structure, and establish a 3D model of the final deformation of the impacted structure based on the several deformation curves drawn, thereby determining the final 3D deformation pattern of the impacted structure.

[0019] In the above scheme, when a 90° vertical concentric collision occurs, the maximum dynamic deformation of the impacted structure is the distance traveled by the single push rod behind the collision point, which is also reflected by the distance traveled by the transparent baffle. Therefore, the maximum deformation of the structure during the collision test is measured in real time by a laser displacement measurement system, and a time history curve of the maximum deformation is displayed on the data display. The moment corresponding to the rebound in the curve is the moment when the collision ends, and this time period is the duration of the collision under this working condition. The single push rod behind the impacted structure where the maximum deformation occurs also undergoes the most obvious lateral movement, which in turn leaves a continuous fluorescent mark on the transparent baffle. Recording this mark with a high-speed camera can reflect the location of the maximum deformation.

[0020] When the impact point is far from the center of gravity of the struck ship, or in the event of an oblique collision, the maximum dynamic deformation of the struck structure is also reflected in the movement distance of the transparent baffle. The maximum deformation of the structure during the collision test is measured in real time by a laser displacement measurement system, and a time history curve of the maximum deformation is displayed on the data display screen. The position of the maximum dynamic deformation of the struck structure changes, and a high-speed camera is used to record the position of each fluorescent contact mark on the transparent baffle, so that the position of the dynamic deformation of the struck structure can be captured in real time.

[0021] The beneficial effects produced by the present invention are:

[0022] 1. This invention can transform the complex deformation of an impacted structure into the translational motion of a transparent baffle, enabling precise, real-time capture of the impact depth, trajectory of the impact point, and final deformation pattern under random collision conditions. The impact depth is reflected as a single-degree-of-freedom horizontal movement of the transparent baffle, detected by rear-mounted laser displacement. The trajectory of the impact point is determined by recording the location and time of fluorescent contact marks with a high-speed camera. The final deformation pattern, i.e., the post-collision deformation pattern of the impacted structure, can be accurately reproduced in three dimensions by measuring the final distance traveled by each ejector pin.

[0023] 2. The present invention is applicable to monitoring dynamic deformation under conditions of any structural size, any structural form, any impact head style, and any load action position. The present invention can solve the difficulties in measuring dynamic deformation caused by complex hull surfaces or complex impacted structures in ship model collision tests, insufficient measurement space for small-scale scale models, the simultaneous presence of multiple impact points, and random changes in impact points. Specifically, for complex hull surfaces, the present invention changes the length of the push rod behind the surface to ensure that the front end of the push rod simulates the complex hull surface, the end is in the same plane, and is adjacent to the transparent baffle; for insufficient measurement space, the present invention can reduce the number of push rods or reduce the size of a single push pin; for random changes in impact points, the area covered by the push rod can monitor deformation over the entire range.

[0024] 3. For oblique collision or moving load conditions, the impact point will slip on the board, not simply because the deflection of a fixed point is getting larger and larger. Traditional measurement methods, such as laser displacement sensors, can only monitor the dynamic deformation of a fixed point during operation; however, the present invention can monitor the size of the dynamic deformation in real time while capturing the position and time of the fluorescent contact mark to record the movement trajectory of the impact point.

[0025] 4. For the water tank test, since the impacting ship accelerates freely in the water and then hits the side structure of the impacted ship, it is extremely difficult to achieve the coincidence between the actual impact point after the test and the expected impact point before the test. The present invention covers an area around the expected impact point with a top rod for large-scale monitoring, thereby realizing "arbitrary position" collision measurement. Under different collision angles, the impact point is very likely to slide significantly during the collision process, and traditional laser single-point measurement cannot meet the use requirements; however, the present invention can monitor the dynamic deformation size in real time while recording the movement trajectory of the impact point. Therefore, the present invention can measure any position and any angle in the ship collision, further improving the accuracy of the ship model collision experiment.

[0026] 5. The present invention has a simple overall structure, clear operation process, reliable operation, low cost, practical value, and is easy to promote comprehensively. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 This is a schematic diagram of the installation of a device for monitoring dynamic deformation of a structure under collision load according to the present invention;

[0029] Figure 2 This is an overall structural diagram of the device for monitoring dynamic deformation of a structure under collision load according to the present invention;

[0030] Figure 3 yes Figure 2 Side view of

[0031] Figure 4 It is a spring connection structure diagram;

[0032] Figure 5 It is the structure diagram of the top rod;

[0033] Figure 6 This is the structural diagram of the baffle bracket.

[0034] In the figure: 1. Experimental base;

[0035] 2. Collided system; 21. Collided structure; 22. Tooling foundation; 23. Fixture;

[0036] 3. Head banging;

[0037] 4. 3D deformation needle engraving system; 41. Ejector; 411. Spherical rod cap; 412. Conical rod cap; 413. Ejector; 42. Support frame; 43. Transparent baffle; 44. Baffle bracket; 441. Telescopic rod; 442. Horizontal smooth support rod; 443. Support rod clamp; 45. Eye screw; 46. Magnetic base; 47. Clamp spring;

[0038] 5. Laser displacement measurement system;

[0039] 6. High-speed camera; 61. Tripod;

[0040] 7. Laboratory foundation or the hull of the struck ship. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0042] It should be noted that the illustrations provided in the embodiments of the present invention are only schematic illustrations of the basic concept of the present invention. Therefore, the drawings only show components related to the present invention and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0043] In the present invention, it should also be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" and the like are used to indicate positions or locations based on those shown in the accompanying drawings. These terms are intended solely to facilitate the description of the present application and to simplify the description. They are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limiting the present application. Furthermore, the terms "first" and "second" are used solely for descriptive and distinguishing purposes and should not be construed as indicating or implying relative importance.

[0044] like Figure 1-3 As shown, a device for monitoring dynamic deformation of a structure under collision load proposed by the present invention includes an experimental base 1 and a collision system 2 installed on the experimental base 1, a three-dimensional deformation needle engraving system 4, a laser displacement measurement system 5 and a high-speed camera 6.

[0045] The experimental base 1 is fixed to the laboratory foundation or the main hull of the struck ship 7. Threaded holes are arranged at equal intervals on the experimental base 1, and other experimental devices can be connected by bolts.

[0046] The impacted system 2 is fixed on the experimental base 1 and includes a impacted structure 21 . The impacted structure 21 is dynamically deformed under the impact load at random positions of the impact head 3 .

[0047] The impact head 3 can adopt different shapes and styles in the test, and impact the target impact area of ​​the impacted structure 21 at different angles, different speeds, and different masses. The specific impact point may also be random because the movement trajectory of the impact head 3 is not completely restricted.

[0048] The three-dimensional deformation needle carving and re-engraving system 4 is located behind the impacted structure 21 and is used to visualize the deformation process of the impacted structure 21. The three-dimensional deformation needle carving and re-engraving system 4 includes a top rod 41, a support frame 42 and a transparent baffle 43. The top rod 41 is arranged between the impacted structure 21 and the transparent baffle 43, and is kept horizontal and arranged in a matrix to be constrained on the support frame 42. The front end of the top rod 41 is in contact with the impacted structure 21, and the rear end of the top rod 41 is coated with a fluorescent substance. It is close to the transparent baffle 43, but before the test, it is separated by a plastic film so that there is no contact; the top rod 41 and the transparent baffle 43 can both move freely in the horizontal direction. The rear end of the top rod 41 is coated with a fluorescent substance to facilitate the high-speed camera 6 to identify the contact mark left on the transparent baffle 43.

[0049] The laser displacement measurement system 5 is located directly behind the transparent baffle 43, fixed to the experimental base 1 via a universal magnetic base and connected to a data acquisition instrument and a data processing terminal via wires. Its function is to collect deformation during the collision process. The laser displacement measurement system 5 obtains the maximum deformation time history curve during the collision test by measuring the movement distance of the transparent baffle 43 in real time. The specific collection principle is as follows: During the collision test, the impacting ship's ramming head 3 compresses the impacted structure 21 on the side of the impacted ship, causing deformation of the metal material near the collision point. This causes the impacted structure 21 to produce an out-of-plane displacement (deflection), which in turn causes the push rod 41 immediately behind the collision point to move laterally, driving the transparent baffle 43 to move. The movement distance of the transparent baffle 43 reflects the maximum deformation in the collision area, normalizing the dynamic deformation at any location within the impacted structure 21 to the single-degree-of-freedom movement distance of the transparent baffle 43. Therefore, by determining the movement distance of the transparent baffle 43 using the fixed laser displacement measurement system 5, the maximum deflection value at the collision point during the collision test can be obtained, thereby obtaining the deformation time history curve during the collision process. It is worth noting that, because the impact head 3 is often free during the collision test, the collision point on the impacted structure 21 is random; and when the impact head 3 hits the impacted structure 21 at a certain angle, slippage is easily generated between the two. During the collision test, the position of the collision point will not only move perpendicular to the original impacted plane due to extrusion, but will also produce random movement within the plane due to slippage. These movements can be monitored through the movement distance of the transparent baffle 43.

[0050] The high-speed camera 6 is located behind the laser displacement measurement system 5, and is mounted on the experimental base 1 via a tripod 61. It is connected to the data acquisition instrument and the data processing terminal via wires. The high-speed camera 6 is used to record the movement trajectory of the impact point during the collision test. The specific working principle is as follows: the high-speed camera 6 records the process of each fluorescent contact mark on the transparent baffle 43 during the collision. After the experiment is completed, the position (x i ,y i ), and then the position of each mark is matched to the initial vertical plane of the top rod 41 and the side of the struck structure 21 as (X i , Y i ), by drawing (X i , Y i ) points and connect them smoothly to obtain the moving trajectory of the collision point during the experiment; the time when the first fluorescent mark appears is recorded as time t0, and the time when the i-th fluorescent mark appears is recorded as time t i The last fluorescent mark appears at time t n time, t i -t i-1That is, the time required for the impact point to move the long distance between the two push rods (41), t n -t0 is the duration of the collision, and eventually a movement path-time curve of the contact point relative to the initial impact point can be drawn.

[0051] For further optimization, the three-dimensional deformation needle carving and re-engraving system 4 also includes a close spring 47 whose two ends are respectively connected to the collided structure 21 and the transparent baffle 43. The close spring 47 has a small stiffness and is kept in an untensioned state before the start of the test to prevent fluorescent marks from being left on the transparent baffle 43 in advance. When the collided structure 21 elastically rebounds, the transparent baffle 43 can be pulled back to achieve continuous contact between the collided structure 21, the top rod 41 and the transparent baffle 43, ensuring that the deformation of the collided structure 21 and the movement of the transparent baffle 43 are always consistent, so as to monitor the elastic rebound of the collided structure 21 after the collision. After the experiment, the close spring 47 is removed, and the final three-dimensional deformation mode of the collided structure 21 can be established by measuring the final movement distance of each top rod 41.

[0052] Further optimization, the three-dimensional deformation needle engraving system 4 also includes eye screws 45 and magnetic bases 46. The eye screws 45 are fixed to the four corners of the transparent baffle 43. The magnetic bases 46 are installed at the four corners of the impacted structure 21 and arranged opposite to the eye screws 45. Each set of eye screws 45 and the magnetic base 46 are connected by a spring 47. Figure 4 .

[0053] Further optimization, the three-dimensional deformation needle carving system 4 also includes a baffle bracket 44, which is located behind the transparent baffle 43 and is used to install the transparent baffle 43. Figure 6 As shown, the baffle bracket 44 includes a telescopic rod 441, a horizontal smooth support rod 442, and a support rod clamp 443. The telescopic rod 441 is vertically arranged and fixed to the experimental base 1 by bolts or weights. Its length is adjustable to accommodate the impacted structure 21 of different sizes. One end of the horizontal smooth support rod 442 is fixed to the support rod clamp 443 by threads. The support rod clamp 443 can slide up and down along the telescopic rod 441. The other end of the horizontal smooth support rod 442 passes through the transparent baffle 43 to facilitate the installation of the transparent baffle 43. The transparent baffle 43 can move freely along the horizontal smooth support rod 442.

[0054] For further optimization, the length of the top rod 41 is adjusted according to the shape and style of the hit structure 21, ensuring that the front end of the top rod 41 is in contact with the hit structure 21 and the rear end is close to the transparent baffle 43 but does not touch; the number of top rods 41 is adjusted according to the size of the hit structure 21, ensuring that the monitoring range of the top rod 41 covers all areas of the hit structure 21 that may be deformed.

[0055] Further optimization, such as Figure 5As shown, the ejector pin 41 includes a spherical rod cap 411, a conical rod cap 412 and an ejector pin 413. The spherical rod cap 411 and the conical rod cap 412 are respectively fastened to the two ends of the ejector pin 413. The spherical rod cap 411 is close to the impacted structure 21 in front, and the conical rod cap 412 is close to the transparent baffle 43 in the rear. The conical rod cap 412 is coated with fluorescent material to facilitate the high-speed camera (6) to identify the contact mark between it and the transparent baffle (43).

[0056] Further optimization, the struck system 2 also includes a tooling foundation 22 and a fixture 23. The struck structure 21 is fixed to the tooling foundation 22 by bolts around the fixture 23, forming a rigidly fixed boundary condition of the actual ship. The tooling foundation 22 is fixed to the experimental base 1 by bolts.

[0057] Further optimization, transparent baffle 43 has smaller threaded holes and larger support holes at each corner. The smaller threaded holes are used to secure eyebolts 45; the larger support holes are used to pass horizontal smooth support rods 442, ensuring that transparent baffle 43 always moves horizontally during the experiment. Transparent baffle 43 is made of high-strength PVC plastic.

[0058] Further optimization is carried out, the support frame 42 includes two front and rear limiting plates, and the limiting plates are provided with dense limiting holes for multiple push rods 41 to pass through. The push rods 41 can only move horizontally in the holes to transmit the deformation of the collided structure 21. There is a sufficient distance between the limiting plates of the support frame 42 and the collided structure 21 to ensure that it will not be hit during the experiment. The bottom of the support frame 42 is fastened to the tooling base 22 by bolts.

[0059] Accordingly, the present invention further proposes a method for monitoring the dynamic deformation of a structure under a collision load, which uses the above-mentioned device for monitoring the dynamic deformation of a structure under a collision load, comprising:

[0060] S1. Install the structural dynamic deformation monitoring device under the collision load according to the design requirements; specifically including:

[0061] S11, adjust the position of the support frame 42 and fix it on the tooling base 22;

[0062] S12, passing multiple ejector pins 413 through the support frame 42, connecting the front end to the spherical rod cap 411, and the end to the conical rod cap 412, and coating the conical rod cap 412 with fluorescent material;

[0063] S13. Place the baffle bracket 44 and install the transparent baffle 43 on the horizontal smooth support rod 442. Then, push the transparent baffle 43 from the back to the front so that the front end of the push rod 41 is in curved contact with the back of the complex three-dimensional impacted structure 21. Insert the film into the rear end and contact the transparent baffle 43. After determining the position, fix the baffle bracket 44 on the experimental base 1 and record the initial scale of each push rod 41 at the support frame 42.

[0064] S14, connecting the impacted structure 21 and the transparent baffle 43 via the connecting spring 47, and controlling the length of the connecting spring 47 so as to keep it in a non-tensioned state;

[0065] S15 , fixing the laser displacement measurement system 5 at a certain measurement distance behind the rigid transparent baffle 43 ; fixing the high-speed camera 6 behind the laser displacement measurement system 5 .

[0066] S2. Turn on the laser emitting device and data display screen of the laser displacement measurement system 5, and turn on the high-speed camera 6 at the same time; pull out the film between the rear end of the push rod 41 and the transparent baffle 43, control the impact head 3 to impact the impacted structure 21 at an arbitrarily designed angle and position, and then use the structural dynamic deformation monitoring device to measure the impact depth of the impacted structure 21 and the contact position between the impact head 3 and the impacted structure 21 during the collision.

[0067] Collision is divided into two working conditions:

[0068] S21. When a 90° vertical concentric collision occurs, that is, when the centers of mass of the striking ship and the struck ship are both on the common normal line of the initial contact point, the contact point does not move relative to the surface of the struck structure 21, but the striking head 3 will continue to squeeze the struck structure 21 on the side of the struck ship, causing the top rod 41 corresponding to the rear of the impact area to move laterally, and drive the transparent baffle 43 to move horizontally.

[0069] Under this typical operating condition, the maximum dynamic deformation of the impacted structure 21 is the distance traveled by the single push rod 41 after the collision point, which is also reflected in the distance traveled by the transparent baffle 43. Therefore, the maximum deformation of the structure during the collision test is measured in real time by the laser displacement measurement system 5, and a time history curve of the maximum deformation is displayed on the data display screen. The moment when the rebound occurs in the curve is the moment when the collision ends, and this time period is the duration of the collision under this operating condition.

[0070] Under this typical working condition, the rear single push rod 41 where the impacted structure 21 experiences the greatest deformation also undergoes the most obvious lateral movement, which in turn leaves a fluorescent mark on the transparent baffle 43 , indicating the location where the greatest deformation occurs.

[0071] S22. When the impact point is far away from the center of gravity of the struck ship, or an oblique collision occurs, the contact point will slip within the surface of the struck structure 21 under these two working conditions. At the same time, during the movement within the surface, the impact head 3 will also squeeze the side impact structure 21 of the struck ship, and accordingly cause the push rods 41 corresponding to the rear of different impact points to move laterally, and drive the transparent baffle 43 to move horizontally.

[0072] Under these two working conditions, the maximum dynamic deformation of the impacted structure 21 is also reflected in the movement distance of the transparent baffle 43. Therefore, the maximum deformation of the structure during the collision test is also measured in real time by the laser displacement measurement system 5, and the time history curve of the maximum deformation is displayed on the data display screen.

[0073] Under these two working conditions, the position of the maximum dynamic deformation of the impacted structure 21 varies. By recording the position of each fluorescent contact mark on the transparent baffle 43 by the high-speed camera 6, the position of the dynamic deformation of the impacted structure 21 can be captured in real time. The specific implementation idea is: after the experiment, the position of the fluorescent mark appearing during the collision can be determined in sequence by replaying the recorded video (x i ,y i ), and then the position of each mark is matched to the top rod 41 and the impacted structure 21, and is recorded as (X i , Y i ), by drawing (X i , Y i ) points and connect them smoothly to obtain the moving trajectory of the collision point during the experiment; the time when the first fluorescent mark appears is recorded as time t0, and the time when the i-th fluorescent mark appears is recorded as time t i The last fluorescent mark appears at time t n time, t i -t i-1 That is, the time required for the impact point to move the distance between the two push rods 41, t n -t0 is the duration of the collision, and eventually a movement path-time curve of the contact point relative to the initial impact point can be drawn.

[0074] S3. After the collision experiment is finished, the laser emitting device of the laser displacement measurement system 5 and the high-speed camera 6 are turned off.

[0075] S4. Remove the spring 47 and record the final scale of each push rod 41 relative to the support frame 42 near the area where the impacted structure 21 is deformed. Then subtract the initial scale recorded previously to obtain the final deformation size near the impact area. Then, use three-dimensional software to draw the final deformation curves at different cross-sections of the impacted structure 21. Finally, a three-dimensional model of the final deformation of the impacted structure 21 can be established through the drawn curves, thereby establishing the final three-dimensional deformation mode of the impacted structure 21.

[0076] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, or two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0077] The size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0078] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all such improvements and changes should fall within the scope of protection of the appended claims of the present invention.

Claims

1. A device for monitoring dynamic deformation of a structure under collision load, characterized in that: The invention comprises an experimental base (1), a collision system (2) installed on the experimental base (1), a three-dimensional deformation needle engraving system (4), a laser displacement measurement system (5) and a high-speed camera (6); The impacted system (2) is fixed on the experimental base (1) and includes an impacted structure (21). The impacted structure (21) is dynamically deformed under the impact load of the impact head (3) at random positions. The three-dimensional deformation needle carving and re-engraving system (4) is located behind the impacted structure (21) and is used to visualize the deformation process of the impacted structure (21); the three-dimensional deformation needle carving and re-engraving system (4) includes a push rod (41), a support frame (42) and a transparent baffle (43); the push rod (41) is arranged between the impacted structure (21) and the transparent baffle (43), and is kept horizontal and arranged in a matrix on the support frame (42); the front end of the push rod (41) is in contact with the impacted structure (21); the rear end of the push rod (41) is coated with fluorescent material and is adjacent to but not in contact with the transparent baffle (43); the push rod (41) and the transparent baffle (43) can both move freely in the horizontal direction; The laser displacement measurement system (5) and the high-speed camera (6) are both arranged behind the transparent baffle (43); the laser displacement measurement system (5) obtains a time history curve of the maximum deformation of the structure during the collision test by measuring the movement distance of the transparent baffle (43) in real time; the high-speed camera (6) determines the movement trajectory of the collision point by capturing the position and time of each fluorescent contact mark on the transparent baffle (43) during the collision.

2. The device for monitoring dynamic deformation of a structure under collision load according to claim 1, characterized in that: The three-dimensional deformation needle carving and re-engraving system (4) further includes a connecting spring (47) whose two ends are respectively connected to the collided structure (21) and the transparent baffle (43). The connecting spring (47) is kept in a non-tensioned state before the start of the test. When the collided structure (21) elastically rebounds, the transparent baffle (43) can be pulled back to achieve continuous contact between the collided structure (21), the top rod (41) and the transparent baffle (43), ensuring that the deformation of the collided structure (21) and the movement of the transparent baffle (43) are always consistent, so as to monitor the elastic rebound of the collided structure (21) after the collision.

3. The device for monitoring dynamic deformation of a structure under collision load according to claim 2, characterized in that: The three-dimensional deformation needle carving and re-engraving system (4) also includes eye screws (45) and magnetic bases (46), wherein the eye screws (45) are fixed to the four corners of the transparent baffle (43), and the magnetic bases (46) are installed at the four corners of the impacted structure (21) and are arranged one by one opposite to the eye screws (45), and each group of eye screws (45) and the magnetic bases (46) are connected by a tight spring (47).

4. The device for monitoring dynamic deformation of a structure under collision load according to claim 1, characterized in that: The three-dimensional deformation needle carving and re-engraving system (4) also includes a baffle bracket (44), which is located behind the transparent baffle (43) and includes a telescopic rod (441), a horizontal smooth support rod (442) and a support rod clamp (443). The telescopic rod (441) is vertically arranged and fixed on the experimental base (1), one end of the horizontal smooth support rod (442) is fixed in the support rod clamp (443), and the support rod clamp (443) can be slid up and down along the telescopic rod (441); the other end of the horizontal smooth support rod (442) passes through the transparent baffle (43) to realize the installation of the transparent baffle (43).

5. The device for monitoring dynamic deformation of a structure under collision load according to claim 1, characterized in that: The laser displacement measurement system (5) and the high-speed camera (6) are respectively connected to a data acquisition instrument and a data processing terminal via wires.

6. The device for monitoring dynamic deformation of a structure under collision load according to claim 1, characterized in that: The length of the push rod (41) is adjusted according to the shape and style of the impacted structure (21), ensuring that the front end of the push rod (41) contacts the impacted structure (21) and the rear end contacts the transparent baffle (43); the number of the push rods (41) is adjusted according to the size of the impacted structure (21), ensuring that the monitoring range of the push rod (41) covers all areas of the impacted structure (21) that may be deformed.

7. The device for monitoring dynamic deformation of a structure under collision load according to claim 1, characterized in that: The ejector pin (41) comprises a spherical rod cap (411), a conical rod cap (412) and an ejector pin (413). The spherical rod cap (411) and the conical rod cap (412) are respectively fastened to two ends of the ejector pin (413). The spherical rod cap (411) is close to the impacted structure (21) in front, and the conical rod cap (412) is close to the transparent baffle (43) in the rear. The conical rod cap (412) is coated with fluorescent material.

8. The device for monitoring dynamic deformation of a structure under collision load according to claim 1, characterized in that: The struck system (2) further comprises a tooling foundation (22) and a fixture (23); the struck structure (21) is fixed to the tooling foundation (22) by bolts around the fixture (23), forming a boundary condition of rigid fixation of the actual ship; and the tooling foundation (22) is fixed to the experimental base (1) by bolts.

9. A method for monitoring dynamic deformation of a structure under collision load, characterized in that: The device for monitoring dynamic deformation of a structure under a collision load according to any one of claims 1 to 8 comprises: S1. Install the structural dynamic deformation monitoring device under the collision load according to the design requirements; S2, turning on the laser emitting device and the data display screen of the laser displacement measurement system (5), and turning on the high-speed camera (6); controlling the impact head (3) to impact the impacted structure (21) at an arbitrarily designed angle and position, and then measuring the impact depth of the impacted structure (21) during the collision process by the laser displacement measurement system (5), and recording the contact position between the impact head (3) and the impacted structure (21) by the high-speed camera (6); S3. After the collision experiment is completed, the laser emission device of the laser displacement measurement system (5) is turned off, and the high-speed camera (6) is turned off; S4. Remove the spring (47) and record the final scale of each push rod (41) relative to the support frame (42) near the area where the impacted structure (21) is deformed, and then subtract the initial scale recorded previously to obtain the final deformation size near the impact area; then use three-dimensional software to draw the final deformation curves at different cross sections of the impacted structure (21), and establish a three-dimensional model of the final deformation of the impacted structure (21) through the drawn deformation curves, thereby establishing the final three-dimensional deformation mode of the impacted structure (21).

10. The method for monitoring dynamic deformation of a structure under collision load according to claim 9, characterized in that: When a 90° vertical concentric collision occurs, the maximum dynamic deformation of the collided structure (21) is the movement distance of the single push rod (41) behind the collision point, which is also reflected as the movement distance of the transparent baffle (43). Therefore, the maximum deformation of the structure during the collision test is measured in real time by the laser displacement measurement system (5), and the time history curve of the maximum deformation is displayed on the data display screen. The moment corresponding to the rebound in the curve is the moment when the collision ends, and this time period is the duration of the collision under this working condition. The single push rod (41) behind the collided structure (21) where the maximum deformation occurs also undergoes the most obvious lateral movement, and accordingly, a fluorescent mark is continuously left on the transparent baffle (43). The mark is recorded by the high-speed camera (6) to reflect the position where the maximum deformation occurs. When the impact point is far away from the center of gravity of the struck ship, or when an oblique collision occurs, the maximum dynamic deformation of the struck structure (21) is also reflected in the movement distance of the transparent baffle (43). The maximum deformation of the structure during the collision test is measured in real time by the laser displacement measurement system (5), and the time history curve of the maximum deformation is displayed on the data display screen; the position of the maximum dynamic deformation of the struck structure (21) is variable, and the position of each fluorescent contact mark on the transparent baffle (43) is recorded by a high-speed camera (6), and the position of the dynamic deformation of the struck structure (21) can be captured in real time.

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