A large ship model berthing and mooring wharf fender simulation device and method

Abstract

This invention provides a device and method for simulating the berthing and mooring of large ship models at docks, including a cam, a steering slider assembly, and a linear spring. One side of the steering slider assembly is connected to a push rod that can move up and down under the rotation of the cam. The end of the push rod away from the steering slider assembly contacts the circumferential side of the cam, and the side of the steering slider assembly away from the push rod is connected to the linear spring. This invention has the following advantages: Based on different radii and curve slopes of the cam, three marker points are set on the surface of the cam. When the cam is driven to rotate between these points, the complex nonlinear changes of the fender can be simulated. Therefore, this invention utilizes the stroke of the cam so that the deformation of only one spring can simulate the complex nonlinear changes of the fender, thereby solving the problem that the curve in the compression range of 35% to 75% cannot be simulated in the prior art.

Description

Technical Field

[0001] This invention relates to the field of fender simulation technology, and in particular to a fender simulation device and method for berthing and mooring large ship models at docks. Background Technology

[0002] Over the past few decades and for the foreseeable future, various types of transport vessels have been and will continue to undergo a transformation towards larger sizes. For example, container ships have increased from a maximum of 8,000 TEUs a decade ago to 24,000 TEUs currently, and 40,000 TEU ships are already under development. These large ships have enormous inertia, making their berthing a major challenge. The engineering community needs to prepare matching fender devices to simultaneously protect both the dock and the ship. In the laboratory simulation stage, ship dock berthing and mooring model tests are often conducted in marine engineering tanks. The amplitude of hull motion, maximum cable tension, and fender reaction force are the standards for judging whether a ship can berth safely. Hull motion measurement and cable mechanical performance simulation have mature technologies. Compared with motion measurement, cable performance simulation, and tension measurement, fender mechanical performance simulation and reaction force testing are more difficult. In actual engineering, fenders are mainly made of rubber, and the typical reaction force and deformation rate have a nonlinear relationship that is not monotonically increasing. The deformation-force curve of a common rubber fender shows (e.g.) Figure 1 As shown in the figure, in the range of 0% to 20% deformation, the two show a linear increasing relationship. In the range of 20% to 35%, the linear relationship weakens, but the force still increases with the increase of deformation. In the range of 35% to 62.5%, the force decreases significantly with the increase of deformation. After 62.5%, the force increases again with the increase of deformation.

[0003] The closest existing technologies can be found in the patent (CN117906907A) filed by Shanghai Jiao Tong University on January 24, 2024, which uses spring displacement as the force-bearing structure, and the patent (CN120327731A) filed by Tianjin Water Transport Engineering Research Institute of the Ministry of Transport on April 25, 2025, which attempts to simulate the idea of ​​the curve after 35% in the figure above using electronic devices.

[0004] Among them, the invention of Shanghai Jiao Tong University provides a nonlinear fender simulation device, including a base plate, a crossbeam assembly on the top of one side of the base plate, a bumper assembly movably connected to the crossbeam assembly, a first spring assembly connected to the bumper assembly via a first connecting rope, and a counterweight assembly located on the side of the base plate away from the crossbeam assembly via a second connecting rope. A tension sensor is installed on the second connecting rope between the first spring assembly and the counterweight assembly. The counterweight assembly includes a counterweight connected to the second connecting rope and a housing located directly below the counterweight. A second spring assembly connected to the counterweight via a third connecting rope is provided inside the housing. A limiting rope ensures linear tension of the spring. After the limiting rope is activated, the counterweight is pulled up and activated. The reaction force generated by the spring is offset by the weight of the counterweight, thereby realizing the nonlinear stage. However, the invention of Shanghai Jiao Tong University cannot effectively simulate the compression range after 35%, which has considerable limitations. The purpose of this invention is to solve the problem that the curve in the compression range of 35% to 75% cannot be simulated in the prior art.

[0005] The invention by the Tianjin Institute of Water Transport Engineering, Ministry of Transport, employs electronic components including a controller, a fender force measuring component, and a drive mechanism. The fender force measuring component is equipped with a force sensor for measuring the impact force it receives, and the force sensor is electrically connected to the controller. The output end of the drive mechanism is connected to a moving mechanism capable of translating along the direction of the impact force. The fender force measuring component is mounted on the moving mechanism and translates synchronously with it. The drive component is also electrically connected to the controller. The controller calculates the corresponding deformation amount using the reaction force-deformation curve and converts the deformation amount into the translation amount of the moving mechanism, simulating fenders of different stiffnesses. However, the invention by the Tianjin Institute of Water Transport Engineering, Ministry of Transport, relies heavily on electronic components for its key structures, which limits its adaptability to actual wading conditions. Summary of the Invention

[0006] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a large ship model berthing and mooring dock fender simulation device and method to solve the problems that the prior art cannot effectively simulate the range after 35% compression, has considerable limitations, and has poor adaptability to actual wading conditions.

[0007] To achieve the above and other related objectives, the present invention provides the following technical solution:

[0008] A large ship model berthing and mooring dock fender simulation device includes a cam, a steering slider assembly, and a linear spring that can elastically contract under the action of the cam and the steering slider assembly; a drive assembly for driving the cam to rotate is connected to the cam through a concentric transmission shaft; a push rod that can move up and down under the action of the rotation of the cam is connected to one side of the steering slider assembly; the end of the push rod away from the steering slider assembly contacts the circumferential side of the cam; and the side of the steering slider assembly away from the push rod is connected to the linear spring.

[0009] In one embodiment of the present invention, the surface of the cam away from the drive assembly is movably connected to a cam back plate for mounting the cam on a simulated field via a concentric drive shaft, and the end of the linear spring away from the steering slider assembly is connected to a spring fixing plate for mounting the linear spring on the simulated field.

[0010] In one embodiment of the present invention, the cam is symmetrically arranged along its center line and a single cycle end mark is provided at the center line position of the cam. The surface of the cam away from the single cycle end mark is provided with a cam stroke start mark and a cam stroke end mark symmetrically arranged along the center line. The surface of the cam is also provided with points 1, 2 and 3 located between the cam stroke start mark and the single cycle end mark and used to simulate the relationship between fender reaction force and deformation rate in different intervals.

[0011] In one embodiment of the present invention, the drive assembly includes a gear connected to the concentric drive shaft and located on the surface of the cam away from the cam back plate, and a rack meshing with the gear, wherein a top plate that can contact the hull is mounted on one end of the rack.

[0012] In one embodiment of the present invention, the steering slider assembly includes an L-shaped guide rail, a first steering slider and a second steering slider slidably connected to the L-shaped guide rail, wherein the L-shaped guide rail includes a first guide rail perpendicular to each other and slidably connected to the first steering slider and a second guide rail slidably connected to the second steering slider, one side of the first steering slider is connected to the end of the push rod away from the cam, and one side of the second steering slider is connected to the linear spring.

[0013] In one embodiment of the present invention, the side of the first steering slider away from the push rod and the side of the second steering slider away from the linear spring are movably connected to both ends of the first connecting member, the midpoint of the first connecting member is movably connected to one end of the second connecting member, and the end of the second connecting member away from the first connecting member is movably connected to the side of the second guide rail close to the first guide rail.

[0014] A method for simulating the berthing and mooring of large ship models, based on the aforementioned simulation device for berthing and mooring of large ship models, includes the following steps: Under the action of waves, the hull pushes the rack through the top plate, and the rack drives the cam to rotate counterclockwise through the gear. During the rotation from the starting point mark of the cam stroke to point 1, the radius of the cam gradually increases, thereby pushing the push rod to move upward, thereby causing the linear spring to elastically contract. The force on the linear spring increases approximately linearly, thus simulating the range of 0-20%.

[0015] During the rotation from point 1 to point 2, although the radius of the cam gradually increases, the slope of the curve begins to decrease, and the rate of increase of the cam radius is less than in the previous segment, thus simulating the range of 20% to 35%. After reaching its maximum value at point 2, during the rotation from point 2 to point 3, the radius of the cam begins to decrease, causing the push rod to move downwards and the deformation of the linear spring to decrease, thus simulating the range of 35% to 67.5%. From point 3 to the end point of the single cycle, the radius of the cam increases again, causing the push rod to move upwards again, the deformation of the linear spring to increase again, and the force on the linear spring to increase again, thus simulating the range of 67.5% to 75%.

[0016] As described above, the present invention provides a large ship model berthing and mooring dock fender simulation device and method with the following advantages: The present invention uses the collision between the hull and the top plate to push the rack, which, under the action of the rack and gears, drives the cam to rotate, thereby driving the push rod to move up and down. Under the action of the steering slider assembly, the linear spring can elastically contract, and the reaction force of the linear spring is equivalent to the reaction force provided by the fender. The present invention sets three marker points on the surface of the cam according to different radii and curve slopes. When the cam rotates between these points, the complex nonlinear changes of the fender can be simulated. Therefore, the present invention utilizes the cam's stroke to simulate the complex nonlinear changes of the fender using only the deformation of a single spring, thus solving the problem that the curve in the compression range of 35% to 75% cannot be simulated in the prior art. Furthermore, the present invention can use 3D printing technology, resulting in lower costs, simpler structure, better adaptability, clearer motion relationships, and easier understanding, teaching, and fault diagnosis. Attached Figure Description

[0017] Figure 1 The diagram shows the relationship between deformation and stress in a common rubber fender.

[0018] Figure 2 The diagram shown is a structural schematic of the large ship model berthing and mooring dock fender simulation device disclosed in this embodiment of the invention without the drive components installed.

[0019] Figure 3The diagram shows the overall structure of the large ship model berthing and mooring dock fender simulation device disclosed in this embodiment of the invention.

[0020] Figure 4 The diagram shows the structure of the cam in the large ship model berthing and mooring dock fender simulation device disclosed in this embodiment of the invention.

[0021] Figure 5 This is a schematic diagram of the overall process of the large ship model berthing and mooring dock fender simulation method disclosed in the embodiments of the present invention.

[0022] Figure 6 The diagram shows a comparison between the test force and the ideal force of a linear spring in the simulation method for berthing and mooring of a large ship model at a dock disclosed in this embodiment of the invention.

[0023] Component designation explanation

[0024] 1. Cam; 2. Concentric drive shaft; 3. Cam back plate; 4. Push rod; 5. Sliding sleeve; 6. Steering slider assembly; 61. L-shaped guide rail; 611. First guide rail; 612. Second guide rail; 62. First steering slider; 63. Second steering slider; 64. First connecting piece; 65. Second connecting piece; 7. Linear spring; 8. Spring fixing plate; 9. Drive assembly; 91. Gear; 92. Rack; 93. Top plate. Detailed Implementation

[0025] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. It should be noted that, unless otherwise specified, the following embodiments and features described herein can be combined with each other.

[0026] The first embodiment of the present invention relates to a fender simulation device for berthing and mooring large ship models at a dock. Please refer to [link / reference]. Figures 2 to 3 It includes a cam 1, a steering slider assembly 6, and a linear spring 7 that can elastically contract under the action of the cam 1 and the steering slider assembly 6. The cam 1 is symmetrically arranged along its centerline, and a single-cycle end mark is provided at the centerline position of the cam 1. On the surface of the cam 1 away from the single-cycle end mark, there are cam stroke start mark and cam stroke end mark symmetrically arranged along the centerline. The surface of the cam 1 also has points 1, 2, and 3 located between the cam stroke start mark and the single-cycle end mark, used to simulate the relationship between fender reaction force and deformation rate in different intervals. For details, please refer to [link to relevant documentation]. Figure 4 ;

[0027] It should be noted that the curvature at the cam travel start point marker is 0.078, and the radius of curvature is 12.76; the curvature at point 1 is 0.104, and the radius of curvature is 9.54; the curvature at point 2 is 0.144, and the radius of curvature is 6.91; the curvature at point 3 is 0.042, and the radius of curvature is 23.26; the curvature at the single cycle end point marker is 0.2, and the radius of curvature is 5; and the curvature at the cam travel end point marker is 0.065, and the radius of curvature is 15.32.

[0028] exist Figure 3 In the cam 1, a drive assembly 9 for driving the cam 1 to rotate is connected to the cam 1 via a concentric drive shaft 2. The surface of the cam 1 away from the drive assembly 9 is movably connected to a cam back plate 3 for mounting the cam 1 on the simulated field via the concentric drive shaft 2. The drive assembly 9 includes a gear 91 connected to the concentric drive shaft 2 and located on the surface of the cam 1 away from the cam back plate 3, and a rack 92 meshing with the gear 91. A top plate 93 that can contact the hull is mounted on one end of the rack 92. It should be noted that the rack 92 can be pushed by the collision between the hull and the top plate 93. Under the action of the rack 92 and the gear 91, the cam 1 can be driven to rotate.

[0029] Please see Figure 2 and Figure 3 The steering slider assembly 6 is connected to a push rod 4 on one side, which can move up and down under the rotation of the cam 1. The end of the push rod 4 away from the steering slider assembly 6 is in contact with the circumferential side of the cam 1. It should be noted that the cam back plate 3 is provided with a sliding sleeve 5 integrally formed with the cam back plate 3 and slidably connected to the push rod 4. The side of the steering slider assembly 6 away from the push rod 4 is connected to a linear spring 7. The end of the linear spring 7 away from the steering slider assembly 6 is connected to a spring fixing plate 8 for mounting the linear spring 7 on the simulated field.

[0030] The steering slider assembly 6 includes an L-shaped guide rail 61, a first steering slider 62 and a second steering slider 63 slidably connected to the L-shaped guide rail 61. The L-shaped guide rail 61 includes a first guide rail 611 that is perpendicular to each other and slidably connected to the first steering slider 62, and a second guide rail 612 that is slidably connected to the second steering slider 63. The first guide rail 611 and the second guide rail 612 are integrally formed. One side of the first steering slider 62 is connected to the end of the push rod 4 away from the cam 1, and one side of the second steering slider 63 is connected to the linear spring 7. The side of the first steering slider 62 away from the push rod 4 and the side of the second steering slider 63 away from the linear spring 7 are movably connected to both ends of the first connecting member 64 through a rotating shaft. The midpoint of the first connecting member 64 is movably connected to one end of the second connecting member 65 through a rotating shaft. The end of the second connecting member 65 away from the first connecting member 64 is movably connected to the side of the second guide rail 612 close to the first guide rail 611 through a rotating shaft.

[0031] Specifically, the working principle of this device is as follows: Under the action of the waves, the hull pushes the rack 92 through the top plate 93. The rack 92 drives the cam 1 to rotate through the gear 91. The rotation of the cam 1 will further drive the push rod 4 to move up and down. The push rod 4 is rigidly fixed to the first steering slider 62. Under the action of the two connecting parts and the L-shaped guide rail 61, the vertical displacement of the first steering slider 62 will be equivalent to the horizontal displacement of the second steering slider 63. The horizontal displacement of the second steering slider 63 will compress the linear spring 7 fixed between the second steering slider 63 and the spring fixing plate 8. The reaction force of the linear spring 7 is equivalent to the reaction force provided by the fender. In practical applications, force sensors or other instruments for detecting the reaction force and deformation of the linear spring 7 will be installed on the linear spring 7 or in the simulated field according to the actual situation.

[0032] The second embodiment of the present invention relates to a method for simulating the berthing and mooring of large ship models at a fender, the process of which is as follows: Figure 5 As shown, the details are as follows:

[0033] Step 101: Under the action of the waves, the hull pushes the rack 92 through the top plate 93. The rack 92 drives the cam 1 to rotate counterclockwise through the gear 91. During the rotation from the starting point mark of the cam stroke to point 1, the radius of the cam 1 gradually increases, thereby pushing the push rod 4 to move upward, which causes the linear spring 7 to elastically contract. The force on the linear spring 7 increases approximately linearly, thus simulating the range of 0-20%.

[0034] In step 102, during the rotation from point 1 to point 2, although the radius of cam 1 is gradually increasing, the slope of the curve begins to decrease, and the rate of increase of the radius of cam 1 is less than that of the previous segment, which can simulate the range of 20% to 35%.

[0035] In step 103, after reaching the maximum value at point 2, during the rotation from point 2 to point 3, the radius of cam 1 begins to decrease, causing push rod 4 to move downward and the deformation of linear spring 7 to decrease, thereby simulating the range of 35% to 67.5%.

[0036] Step 104: Rotate from point 3 to the end point of the single cycle. The radius of cam 1 increases again, so push rod 4 moves upward again. The deformation of linear spring 7 increases again, and the force on linear spring 7 increases again, thus simulating the range of 67.5% to 75%.

[0037] Specifically, please refer to Figure 4The starting point of the cam stroke is marked by a blue arrow, and the ending point of the cam stroke is marked by a yellow arrow. During the counterclockwise rotation of cam 1, from the starting point to point 1, cam 1 pushes push rod 4 upward, which is equivalent to compressing linear spring 7. The force on linear spring 7 increases approximately linearly. From point 1 to point 2, the slope of the curve begins to decrease. After reaching the highest point at point 2, push rod 4 moves downward at point 3, and the deformation of linear spring 7 decreases, thus making the slope of the curve negative. The red arrow marks the end point of a single cycle. During the process from point 3 to the end point, push rod 4 rises again, and linear spring 7 is compressed again. Therefore, the deformation of linear spring 7 increases, and the force increases again.

[0038] More specifically, starting from the point indicated by the blue arrow, rotating counterclockwise to point 1, the radius of cam 1 gradually increases, and the compression of linear spring 7 gradually increases, simulating the 0-20% range; in the range from point 1 to point 2, the rate of increase of the radius of cam 1 is less than the previous segment, thus simulating the 20%-35% range, reaching its maximum value at point 2; subsequently, from point 2 to point 3, the radius of cam 1 begins to decrease, causing push rod 4 to move downwards, reducing the deformation of linear spring 7, simulating the 35%-67.5% range; from point 3 to the end point indicated by the red arrow, the radius of cam 1 increases again, causing push rod 4 to move upwards again, and the deformation of linear spring 7 to increase again, which, in actual measurements, can simulate the 67.5%-75% range; the counterclockwise rotation actually simulates the situation of a ship with rubber fenders thrusting backwards. If the device is actually installed, the actual effective range should be between the blue and yellow arrows.

[0039] Furthermore, in the simulation test, this device can also use the motion plugin in SolidWorks to perform motion analysis and obtain relevant data. The movement of cam 1 is aided by the motor in the motion plugin. Cam 1 rotates at a speed of 5 RPM, which also helps to obtain displacement data. After reaching the end point of a single cycle, the symmetrical cam 1 continues to rotate, which is equivalent to simulating the situation where the fender pushes the ship back after being compressed to the limit. In reality, rack 92 and gear 91 are installed in similarly shaped components. The key device is supported by a support column to ensure the stability of the entire device. When the ship is subjected to force and moves towards the shore, rack 92 is pushed by top plate 93. Rack 92 drives gear 91 to rotate. Gear 91 drives cam 1 to rotate through concentric transmission shaft 2 to realize the simulation of the fender. The working principle of the device after cam 1 moves is as described in the motion example, which should be a sub-cycle in the motion example.

[0040] Taking into account the size of the prototype and the testing capability of the water tank, the scale ratio of the model test was selected as λ = 1:60, the test water depth was 2.42m, and the displacement similarity calculation process was as follows: According to the similarity principle, when the linear scale reduction is 100%, That is, L m =2000 / 60≈33.33mm, the maximum value appears at 35% compression, i.e., at 11.6655mm, based on the rotational displacement of the cam driven by the constant speed motor: Considering the convenience of actual dimensions and the lever design in the aforementioned Shanghai Jiao Tong University patent, a cam radius of r = 10mm was chosen, reaching its maximum value at approximately stroke s = 10.0531mm; the lowest point of "negative stiffness" is at 62.5% of the compression, i.e., 20.8313mm, and the test stroke reaches the "lowest point of negative stiffness" at 18.4307mm; the process of force similarity calculation is as follows: Considering that freshwater can be modified to approximate the conditions of actual seawater in the laboratory, λ can be set to 1. Combining this with the above λ = 1:60, the maximum reaction force is 16.4N. Using a linear spring with a k value of 8N / mm, its free length is 62.4776mm, the maximum reaction force is 16.13N, and the relative error is 1.64%.

[0041] By combining similar proportions, the SolidWorks data is imported into an Excel spreadsheet for plotting, obtaining a displacement versus force graph. Since SolidWorks acquires data in frames with equal intervals, the displacement data is (5pi / 3)*t. Automeris visualization is used to read the 0%–67.5% confidence data points. The two are then integrated to create a comparison graph of ideal and test data. For details, please refer to [link to documentation]. Figure 6 .

[0042] In summary, this invention utilizes the collision between the hull and the top plate 93 to push the rack 92. Under the action of the rack 92 and the gear 91, the cam 1 rotates, thereby driving the push rod 4 to move up and down. Under the action of the steering slider assembly 6, the linear spring 7 elastically contracts, and the reaction force of the linear spring 7 is equivalent to the reaction force provided by the fender. This invention sets three marker points on the surface of the cam 1 according to different radii and curve slopes. When driving the cam 1 to rotate between these points, the complex nonlinear changes of the fender can be simulated. Therefore, this invention utilizes the stroke of the cam 1 so that the deformation of only one spring can simulate the complex nonlinear changes of the fender, thus solving the problem that the curve in the compression range of 35% to 75% cannot be simulated in the prior art. Furthermore, this invention can be printed using 3D printing technology, which is more cost-effective, has a simple structure, good adaptability, clear motion relationships, and is easy to understand, teach, and diagnose.

[0043] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. All equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this invention should still be covered by the claims of this invention.

Claims

1. A simulation device for berthing and mooring fenders of a large ship model, characterized in that: The system includes a cam (1), a steering slider assembly (6), and a linear spring (7) that can elastically contract under the action of the cam (1) and the steering slider assembly (6); a drive assembly (9) for driving the cam (1) to rotate is connected to the cam (1) through a concentric drive shaft (2); a push rod (4) that can move up and down under the action of the rotation of the cam (1) is connected to one side of the steering slider assembly (6); the end of the push rod (4) away from the steering slider assembly (6) is in contact with the circumferential side of the cam (1); and the side of the steering slider assembly (6) away from the push rod (4) is connected to the linear spring (7). The cam (1) is symmetrically arranged along its center line and a single cycle end mark is provided at the center line position of the cam (1). The surface of the cam (1) away from the single cycle end mark is provided with a cam stroke start mark and a cam stroke end mark symmetrically arranged along the center line. The surface of the cam (1) is also provided with points 1, 2 and 3 located between the cam stroke start mark and the single cycle end mark and used to simulate the relationship between fender reaction force and deformation rate in different intervals. As the cam travels from the starting point mark to point 1, the radius of cam (1) gradually increases. As it travels from point 1 to point 2, although the radius of cam (1) also gradually increases, the slope of the curve begins to decrease, and the rate of increase of the radius of cam (1) is less than that of the previous period. After reaching its maximum value at point 2, the radius of cam (1) begins to decrease as it travels from point 2 to point 3. As it travels from point 3 to the end point mark of the single cycle, the radius of cam (1) increases again.

2. The large ship model berthing and mooring dock fender simulation device according to claim 1, characterized in that: The surface of the cam (1) away from the drive assembly (9) is movably connected via a concentric drive shaft (2) to a cam back plate (3) for mounting the cam (1) on the simulated field, and the end of the linear spring (7) away from the steering slider assembly (6) is connected to a spring fixing plate (8) for mounting the linear spring (7) on the simulated field.

3. The large ship model berthing and mooring dock fender simulation device according to claim 2, characterized in that: The drive assembly (9) includes a gear (91) connected to the concentric drive shaft (2) and located on the surface of the cam (1) away from the cam back plate (3) and a rack (92) meshing with the gear (91), with a top plate (93) mounted on one end of the rack (92) that can contact the hull.

4. The large ship model berthing and mooring dock fender simulation device according to claim 1, characterized in that: The steering slider assembly (6) includes an L-shaped guide rail (61), a first steering slider (62) slidably connected to the L-shaped guide rail (61), and a second steering slider (63). The L-shaped guide rail (61) includes a first guide rail (611) that is perpendicular to each other and slidably connected to the first steering slider (62) and a second guide rail (612) that is slidably connected to the second steering slider (63). One side of the first steering slider (62) is connected to the end of the push rod (4) away from the cam (1), and one side of the second steering slider (63) is connected to the linear spring (7).

5. The large ship model berthing and mooring dock fender simulation device according to claim 4, characterized in that: The side of the first steering slider (62) away from the push rod (4) and the side of the second steering slider (63) away from the linear spring (7) are movably connected to both ends of the first connector (64). The midpoint of the first connector (64) is movably connected to one end of the second connector (65). The end of the second connector (65) away from the first connector (64) is movably connected to the side of the second guide rail (612) close to the first guide rail (611).

6. A method for simulating the berthing and mooring of large ship models at a dock, characterized in that: The large ship model berthing and mooring dock fender simulation device according to claim 3 includes the following steps: Under the action of the waves, the hull pushes the rack (92) through the top plate (93). The rack (92) drives the cam (1) to rotate counterclockwise through the gear (91). During the rotation from the starting point mark of the cam stroke to point 1, the radius of the cam (1) gradually increases, thereby pushing the push rod (4) to move upward, thereby causing the linear spring (7) to elastically contract. The force on the linear spring (7) increases approximately linearly, thereby simulating the fender compression in the range of 0~20%. During the rotation from point 1 to point 2, although the radius of cam (1) gradually increases, the slope of the curve begins to decrease. The rate of increase of the radius of cam (1) is less than that of the previous section, so the simulated fender compression is in the range of 20% to 35%. After reaching the maximum value at point 2, during the rotation from point 2 to point 3, the radius of cam (1) begins to decrease, which causes push rod (4) to move downward and the deformation of linear spring (7) to decrease, thereby simulating the fender compression in the range of 35% to 67.5%. As the cam (1) rotates from point 3 to the end point of the single cycle, its radius increases again, causing the push rod (4) to move upward again. The deformation of the linear spring (7) increases again, and the force on the linear spring (7) increases again, thus simulating the fender compression in the range of 67.5% to 75%.

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