Visual calibration target device for dynamic displacement monitoring of a steel trestle

Abstract

The utility model relates to visual calibration target device technical field, specifically disclose a kind of visual calibration target device of steel trestle dynamic displacement monitoring, including target mechanism, the upper end side of the target mechanism is provided with wire arrangement mechanism, the front lower end of the target mechanism is provided with auxiliary flickering mechanism;The target mechanism includes mounting plate, suspension pole, target main body, wiring seat, lamp holder, outer ring reference lamp bead, intermediate layer reference lamp bead and inner ring reference lamp bead.This scheme can adapt to different monitoring distance and camera focal length by the reference lamp bead design of multiple circle layer distribution, ensure target quick identification and stable tracking by outer ring double-layer concentric circle lamp bead under long-distance large visual angle, provide high-precision positioning by intermediate layer polygon lamp bead in medium distance, and rely on snowflake inner ring lamp bead to realize ultimate calibration in nearest distance, only single target can cover the full-scale monitoring requirement from bridge overall shaking to local slight deformation.

Description

Technical Field

[0001] This utility model relates to the field of visual calibration target device technology, and specifically discloses a visual calibration target device for dynamic displacement monitoring of steel trestle bridges. Background Technology

[0002] Steel trestle bridges are temporary bridge structures widely used in the construction of various engineering projects, especially when crossing rivers, valleys, or other obstacles. They are typically made of steel, possessing high strength and flexibility, and can be quickly erected and dismantled to meet temporary traffic needs during construction.

[0003] Steel trestle bridges not only play an important role in highway and railway construction, but also have wide applications in water conservancy, power, mining and other fields. For example, the utility model authorized by announcement number CN222505753U discloses a visual test bridge calibration target, which relates to the field of calibration target technology. It includes a shell, a light-shielding baffle fixedly installed on the upper surface of the shell, and an illumination strip fixedly installed on one side surface of the shell to facilitate the location of the target in low light conditions. A marking mechanism for visual side viewing is set at the center of the shell. The marking mechanism includes a limiting frame, which is fixedly installed on one side surface of the shell. An adjustable installation mechanism is also set on one side surface of the shell. The installation mechanism includes an installation plate, which is fixedly installed on one side surface of the shell. A light-emitting component is set between the marking mechanism and the installation mechanism. In this solution, by setting the marking mechanism and the light-emitting component, the target can flexibly change its marking state or shape according to actual needs, which greatly improves the practicality of the target and ensures that the target remains clearly visible even in low light conditions. Currently, after steel trestle bridges are put into use, their displacement needs to be monitored. The monitoring equipment mainly consists of a high-definition camera and its connected terminal, as well as a visual measurement target, which acts as a marker. By capturing changes in the displacement value of the marker, the dynamic displacement of the trestle bridge can be analyzed. However, most target structures are single light-emitting or reflective units. During periods of high dust or fog, the image quality of a single light-emitting or reflective unit will be greatly reduced. Therefore, flashing lights are used to improve the image quality. However, if the light itself is used to frequently change the current or voltage to flicker, it can easily lead to a significant reduction in the lifespan of the LED beads emitting the light. Furthermore, since most LED beads are connected in series, the failure of one can cause the entire light to fail, making the repair process relatively complicated. Utility Model Content

[0004] In view of this, the purpose of this utility model is to provide a visual calibration target device for dynamic displacement monitoring of steel trestle bridges, so as to solve the problem of improving the resolution accuracy of the camera and the target in the case of poor visibility by making the target light flash.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a visual calibration target device for dynamic displacement monitoring of steel trestle bridges, comprising a target mechanism, a wiring mechanism on one side of the upper end of the target mechanism, and an auxiliary flashing mechanism on the lower front end of the target mechanism.

[0006] The target mechanism includes a mounting plate, a suspension rod, a target body, a terminal block, a lamp holder, an outer ring reference lamp, a middle layer reference lamp, and an inner ring reference lamp;

[0007] The cable laying mechanism includes a winding post, a tightening cap, a notch, and a pull head;

[0008] The auxiliary flashing mechanism includes a notch, bearing, shaft, sleeve, motor, full light-blocking plate, semi-transparent light-blocking plate, and light-transmitting hole.

[0009] Furthermore, the mounting plate has mounting holes that penetrate its interior at the four top corners, a suspension rod is provided at the lower center of the mounting plate, a target body is provided at the lower end of the suspension rod, a terminal block is embedded in the back of the target body, and a lamp holder is provided on the front of the target body. The lamp holder and the terminal block are connected by a wire.

[0010] Furthermore, the lamp holder has a number of outer ring reference lamp beads distributed along the edge of the front side, a number of middle layer reference lamp beads distributed on the front side of the lamp holder, and a number of inner ring reference lamp beads distributed at the center of the lamp holder.

[0011] Furthermore, a cylinder is provided on one side of the lower end of the mounting plate, and a piston rod for extension and retraction is provided inside the cylinder. A connecting block is provided at the end of the piston rod, and a sealing plate is provided on one side of the connecting block.

[0012] Furthermore, several winding posts are arranged side by side on one side of the lower end of the mounting plate. The surface of the winding posts is covered with a tightening cap. Several notches penetrating the interior are opened on the surface of the tightening cap. A pull head is also fixedly installed on the outward end of the winding post.

[0013] Furthermore, the end of the winding post is provided with a slot, and an elastic clip is provided on the inner wall of the tightening cap. The elastic clip and the tightening cap are fixed by screws. The surface of the elastic clip and the groove of the slot are interlocked and fixed. The shape of the elastic clip and the shape of the groove of the slot are both regular hexagons. The elastic clip is made of rubber material.

[0014] Furthermore, connecting rods are provided on both sides of the suspension rod, and support plates are provided at the lower ends of the two connecting rods. A notch is opened on one side of the support plate, and bearings are provided through both sides of the inner wall of the notch. The bearings distributed on both sides are provided with the same shaft through them. The surface of the shaft is interference-fitted with the inner ring wall of any one of the bearings. A motor is provided at the outer end of the shaft. The motor has a drive shaft inside, and the end of the shaft is fixedly connected to the shaft by a coupling.

[0015] Furthermore, a sleeve is provided on the surface of the shaft, a complete light-blocking plate is fixedly installed on one side of the outer ring wall of the sleeve, and a semi-transparent light-blocking plate is fixedly installed on the other end of the outer ring wall of the sleeve away from the complete light-blocking plate. The surface of the semi-transparent light-blocking plate is provided with several light-transmitting holes.

[0016] The working principle and beneficial effects of this scheme are as follows: 1. This scheme, through the design of multi-layered distributed reference LED beads, can adapt to different monitoring distances and camera focal lengths. At long distances and large viewing angles, the outer double-layered concentric circle LED beads ensure rapid target identification and stable tracking. At medium distances, the middle layer of polygonal LED beads provides high-precision positioning. At the closest distance, the snowflake-shaped inner ring LED beads achieve ultimate calibration. A single target can cover the full-scale monitoring needs from the overall swaying of the bridge to local minor deformations, significantly improving the adaptability and ease of operation of the monitoring system.

[0017] 2. As described in 1, its auxiliary flashing mechanism uses a motor to drive the fully light-blocking plate and the semi-transparent light-blocking plate to rotate alternately, thereby achieving periodic blocking and light transmission of the LED light source, forming a continuous flashing effect from full brightness, partial blocking, semi-transparency to full darkness. This external light-blocking method avoids the LEDs from frequently switching on and off, greatly reducing LED wear and extending service life. At the same time, it effectively enhances the camera's ability to capture targets in dusty or foggy environments, improving the reliability and stability of monitoring data.

[0018] Other advantages, objectives, and features of this invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination and study, or may be learned from practice of this invention. The objectives and other advantages of this invention can be realized and obtained through the following description. Attached Figure Description

[0019] Figure 1 This is a schematic diagram showing the distribution of the various mechanisms in the embodiment;

[0020] Figure 2 This is a schematic diagram of the overall front structure of the embodiment;

[0021] Figure 3 This is a schematic diagram of the overall top structure of the embodiment;

[0022] Figure 4 This is a schematic diagram of the overall rear structure of the embodiment;

[0023] Figure 5 This is a schematic diagram of the sealing plate and cylinder connection in an embodiment;

[0024] Figure 6 A top view diagram illustrating the disassembled distribution of the winding post and tightening cap in this embodiment;

[0025] Figure 7 This is a schematic diagram of the card slot and winding post distribution in an embodiment.

[0026] The following are the markings in the attached diagram: 1. Target mechanism; 10. Mounting plate; 11. Mounting hole; 12. Suspension rod; 13. Target body; 14. Terminal block; 15. Lamp holder; 16. Outer ring reference lamp; 17. Middle layer reference lamp; 18. Inner ring reference lamp; 101. Cylinder; 102. Connecting block; 103. Sealing plate;

[0027] 2. Cable routing mechanism; 20. Winding post; 21. Tightening cap; 22. Notch; 23. Pull head; 24. Elastic clip; 25. Clip slot;

[0028] 3. Auxiliary flashing mechanism; 30. Notch; 31. Bearing; 32. Shaft; 33. Motor; 34. Sleeve; 35. Full light-blocking plate; 36. Semi-transparent light-blocking plate; 37. Light-transmitting hole; 38. Support plate; 39. Connecting rod. Detailed Implementation

[0029] The following detailed description illustrates the specific implementation method:

[0030] Example

[0031] like Figures 1 to 7 As shown, a visual calibration target device for dynamic displacement monitoring of a steel trestle bridge is disclosed, including a target mechanism 1, a wiring mechanism 2 is provided on one side of the upper end of the target mechanism 1, and an auxiliary flashing mechanism 3 is provided at the lower front end of the target mechanism 1.

[0032] The target mechanism 1 includes a mounting plate 10, a suspension rod 12, a target body 13, a terminal block 14, a lamp holder 15, an outer ring reference lamp bead 16, a middle layer reference lamp bead 17, and an inner ring reference lamp bead 18.

[0033] The cable laying mechanism 2 includes a winding post 20, a tightening cap 21, a notch 22, and a pull head 23;

[0034] The auxiliary flashing mechanism 3 includes a notch 30, a bearing 31, a shaft 32, a sleeve 33, a motor 34, a fully light-blocking plate 35, a semi-transparent light-blocking plate 36, and a light-transmitting hole 37.

[0035] Mounting plate 10 is a rectangular structure that fits horizontally against the lower end of the bridge. Mounting holes 11 are provided at the four corners of mounting plate 10, with the inner walls of the holes being either smooth or threaded. Screws or bolts are used to pass through the mounting holes 11, allowing mounting plate 10 to be stably installed against the lower end of the bridge. A suspension rod 12 is provided at the lower center of mounting plate 10. The upper end of suspension rod 12 is fixed to mounting plate 10 by welding, serving as a transitional connection. A target body 13 is provided at the lower end of suspension rod 12. The shell of target body 13 is fixed to suspension rod 12 by screws. A terminal block 14 is embedded in the back of target body 13. Terminal block 14 can be connected to an external power switch via wires. A lamp holder 15 is provided on the front of target body 13. The lamp holder 15 is fixed to target body 13 by screws, and the lamp holder 15 is connected to terminal block 14 via wires.

[0036] The front of the lamp holder 15 has several outer ring reference LEDs 16 distributed along the edge. These outer ring reference LEDs 16 are equidistantly distributed in a ring along both the inner and outer sides, forming a double-layer concentric circle structure. This structure is used for rapid identification and initial positioning at long distances and wide viewing angles, ensuring the camera does not lose the target. The front of the lamp holder 15 also has several middle layer reference LEDs 17, forming a polygonal structure. The distribution of the middle layer reference LEDs 17 is slightly denser than that of the outer ring reference LEDs 16, facilitating higher precision sub-pixel level positioning at medium distances. Several inner ring reference LEDs 18 are distributed at the center of the base 15, forming a snowflake structure. The distribution of the inner ring reference LEDs 18 is denser than that of the middle layer reference LEDs 17, providing the ultimate calibration reference in the closest distance or highest resolution mode. Each LED is fixedly embedded and powered on in the base 15. The LED distribution in three different areas allows a single target to cover the full-scale monitoring needs from the overall sway of the bridge to local minor deformations, adapting to cameras with different focal lengths and different monitoring distances without the need to replace or adjust the target.

[0037] A cylinder 101 is provided on one side of the lower end of the mounting plate 10. The cylinder 101 is fixed to the mounting plate 10 by screws. The cylinder 101 is provided with a piston rod for telescopic movement. A connecting block 102 is provided at the end of the piston rod. The connecting block 102 is assembled to the piston rod by screws. A sealing plate 103 is provided on one side of the connecting block 102. The sealing plate 103 is fixed to the connecting block 102 by screws. The sealing plate 103 slides and fits tightly against the end face of the target body 13 near the lamp holder 15. The size of the sealing plate 103 is not smaller than the end face of the target body 13. After the sealing plate 103 moves down to the maximum distance, the sealing plate 103 can cover the entire lamp holder 15, so that when the target is not in use, the lamp bead is covered and protected, maximizing the lifespan of the lamp bead and reducing the number of replacements.

[0038] Several winding posts 20 are arranged side by side on one side of the lower end of the mounting plate 10. One end of the winding post 20 is fixed to the mounting plate 10 by screws. The surface of the winding post 20 is covered with a tightening cap 21. Several notches 22 are opened on the surface of the tightening cap 21, which penetrate through the interior. Preferably, there are two notches 22, and the notches 22 are arranged in a ring at equal intervals along the surface of the tightening cap 21. A pull head 23 is also fixedly installed on the outward end of the winding post 20. When it is necessary to store the excess length of the power line of the terminal block 14, the line is wound around the winding post 20. At this time, the tightening cap 21 can cover the winding post 20 to achieve the wrapping and tightening of the wound line. At the same time, the two notches 22 can be used as the inlet and outlet of the line respectively to ensure the stability of the line during the storage process. The pull head 23 can easily apply force to pull the tightening cap 21 and the winding post 20 to separate them.

[0039] The winding post 20 has a slot 25 at its end, and an elastic clip 24 is provided on the inner wall of the tightening cap 21. The elastic clip 24 and the tightening cap 21 are fixed by screws. The surface of the elastic clip 24 and the groove of the slot 25 are interlocked and fixed. The shape of the elastic clip 24 and the shape of the groove of the slot 25 are both regular hexagons. The elastic clip 24 is made of rubber material. When the tightening cap 21 and the winding post 20 are installed, the elastic clip 24 and the slot 25 are interlocked to achieve a stable connection between the two. When disassembling, the two can be separated by pulling the pull head 23.

[0040] Both sides of the suspension rod 12 are provided with connecting rods 39. One end of the connecting rod 39 is welded and fixed to the surface of the suspension rod 12. The lower ends of the two connecting rods 39 are provided with support plates 38. The support plates 38 are fixed to any one of the connecting rods 39 by screws. A notch 30 is opened on one side of the support plate 38. Bearings 31 are installed through both sides of the inner wall of the notch 30. The connection position of the bearings 31 and the notch 30 is fixed by screws. The same shaft 32 is installed through the bearings 31 distributed on both sides. The surface of the shaft 32 is interference-fitted with the inner ring wall of any one of the bearings 31. A motor 33 is provided at the outer end of the shaft 32. The motor 33 has a rotating shaft for driving inside. The end of the rotating shaft is fixedly connected to the shaft 32 by a coupling. The outer ring wall of the motor 33 is fixedly installed to the side wall of the support plate 38 by a bracket. When the power supply of the motor 33 is turned on, the motor 33 can rotate the rotating shaft and make the shaft 32 rotate stably based on the bearings 31.

[0041] A sleeve 34 is provided on the surface of the shaft 32. The connection between the sleeve 34 and the shaft 32 is fixed by screws. A complete light-blocking plate 35 is fixedly installed on one side of the outer ring wall of the sleeve 34. A semi-transparent light-blocking plate 36 is fixedly installed on the end of the outer ring wall of the sleeve 34 away from the complete light-blocking plate 35. The surface of the semi-transparent light-blocking plate 36 has several light-transmitting holes 37. When the shaft 32 rotates, the sleeve 34 rotates synchronously, so that the complete light-blocking plate 35 and the semi-transparent light-blocking plate 36 alternately block the light of the lamp beads on the lamp holder 15. This creates a flashing effect as the LED emits light, which improves the camera's ability to capture images in dusty or foggy conditions. The light-transmitting hole 37 allows the semi-transparent light-blocking plate 36 to partially transmit light, creating a continuous alternating process from normal illumination to partial light blocking, then to semi-transparent light blocking, then to complete light blocking, and finally back to illumination. This results in a stable flashing effect. By using the light-blocking plate to block and release light, the energy consumption that would otherwise be generated by the LED itself during flashing is reduced, significantly extending the lifespan of the LED.

[0042] In practice

[0043] The target mechanism 1 in this scheme achieves full-scale displacement monitoring through its multi-layered LED layout design. The mounting plate 10 is securely connected to the lower end of the steel trestle bridge through the mounting holes 11, ensuring that the entire device moves synchronously with the bridge. The suspension rod 12, as a rigid connector, suspends the target body 13 below the bridge. Its welding and screw fixing methods ensure structural stability. The terminal block 14 on the back of the target body 13 is connected to an external power source to power the three sets of LEDs on the front lamp holder 15. The outer ring reference LEDs 16 are distributed in a double-layer concentric circle structure, forming a significant light spot cluster when monitoring at long distances or large viewing angles, ensuring that the camera can still quickly capture the target without losing it when the bridge shakes significantly. The middle layer reference LEDs 17 are densely arranged in a polygonal structure, providing a higher density light spot array at medium distances, supporting sub-pixel level image analysis, and accurately capturing medium-amplitude deformations. The inner ring reference LEDs 18 are further densely distributed in a snowflake-like structure, providing an ultimate positioning reference in close-range or high-resolution modes for resolving millimeter-level micro-deformations.

[0044] The auxiliary flashing mechanism 3 enhances visual recognition reliability through mechanical light blocking. The support plate 38 is rigidly connected to the suspension rod 12 via the connecting rod 39, forming a stable support base. The motor 34 drives the shaft 32 to rotate. The shaft 32 rotates smoothly within the recess 30 via bearings 31 on both sides. The sleeve 33 is fixed to the shaft 32 and rotates synchronously with the shaft. The fully light-blocking plate 35 and the semi-transparent light-blocking plate 36 installed on its outer wall move alternately. When the fully light-blocking plate 35 rotates to the front of the lamp holder 15, it completely blocks all the light from the lamp beads. A completely dark state is formed; when the semi-transparent light-blocking plate 36 rotates to the corresponding position, the light-transmitting hole 37 on its surface allows some light to pass through, forming a local light transmission effect; when there is no light-blocking plate, the lamp beads return to the fully bright state. This cycle produces regular lighting changes, simulating a high-frequency flickering effect. In dusty, foggy, or low-light environments, this active flickering can significantly enhance image contrast, reduce motion blur when the camera captures images, improve the signal-to-noise ratio of displacement data, and avoid the lifespan loss caused by directly controlling the flickering of the lamp bead circuit.

[0045] The cable routing mechanism 2 works in conjunction with the protective structure to ensure the durability and ease of maintenance of the device. The winding post 20 is fixed to the lower end of the mounting plate 10 to collect excess wires from the terminal block 14. After the wires are wound around the winding post 20, they are covered and fixed by the tightening cap 21. The notch 22 on its surface serves as the cable inlet and outlet to guide the wiring direction and prevent the cables from becoming messy or loose. The hexagonal rubber snap design of the elastic clip 24 and the end slot 25 of the winding post 20 provides sufficient friction to maintain the wrapped state of the tightening cap 21, while allowing for quick disassembly by applying pulling force through the pull head 23, which is convenient for cable adjustment or replacement. On the other hand, the cylinder 101 pushes the connecting block 102 and the sealing plate 103 to move vertically through the extension and retraction of the piston rod. When monitoring is intermittent or not in operation, the sealing plate 103 moves down and completely covers the front of the lamp holder 15, isolating the lamp beads from direct damage by dust, rain or collision. When monitoring is started, the sealing plate 103 moves up to expose the lamp holder 15.

[0046] The above description is merely an embodiment of this utility model, and common knowledge such as specific structures and characteristics in the solution is not described in detail here. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of this utility model, and these should also be considered within the protection scope of this utility model. These modifications and improvements will not affect the effectiveness of the implementation of this utility model or its practicality.

Claims

1. A visual calibration target device for dynamic displacement monitoring of steel trestle bridges, characterized in that: It includes a target mechanism, a wiring mechanism on one side of the upper end of the target mechanism, and an auxiliary flashing mechanism on the lower front end of the target mechanism; The target mechanism includes a mounting plate, a suspension rod, a target body, a terminal block, a lamp holder, an outer ring reference lamp, a middle layer reference lamp, and an inner ring reference lamp; The cable laying mechanism includes a winding post, a tightening cap, a notch, and a pull head; The auxiliary flashing mechanism includes a notch, bearing, shaft, sleeve, motor, full light-blocking plate, semi-transparent light-blocking plate, and light-transmitting hole.

2. The visual calibration target device for dynamic displacement monitoring of a steel trestle bridge according to claim 1, characterized in that: The mounting plate has mounting holes that penetrate its interior at its four corners. A suspension rod is provided at the lower center of the mounting plate, and a target body is provided at the lower end of the suspension rod. A terminal block is embedded in the back of the target body, and a lamp holder is provided on the front of the target body. The lamp holder and the terminal block are connected by a wire.

3. The visual calibration target device for dynamic displacement monitoring of a steel trestle bridge according to claim 2, characterized in that: The lamp holder has several outer ring reference lamp beads distributed along the edge of its front side, several middle layer reference lamp beads distributed on the front side of the lamp holder, and several inner ring reference lamp beads distributed at the center of the lamp holder.

4. The visual calibration target device for dynamic displacement monitoring of a steel trestle bridge according to claim 3, characterized in that: A cylinder is provided on one side of the lower end of the mounting plate. The cylinder has a piston rod for extension and retraction inside, and a connecting block is provided at the end of the piston rod. A sealing plate is provided on one side of the connecting block.

5. The visual calibration target device for dynamic displacement monitoring of a steel trestle bridge according to claim 4, characterized in that: Several winding posts are arranged side by side on one side of the lower end of the mounting plate. The surface of the winding posts is covered with a tightening cap. Several notches penetrating the interior are opened on the surface of the tightening cap. A pull head is also fixedly installed on the outward end of the winding post.

6. The visual calibration target device for dynamic displacement monitoring of a steel trestle bridge according to claim 5, characterized in that: The end of the winding post is provided with a slot, and an elastic clip is provided on the inner wall of the tightening cap. The elastic clip and the tightening cap are fixed by screws. The surface of the elastic clip and the groove of the slot are interlocked and fixed. The shape of the elastic clip and the shape of the groove of the slot are both regular hexagons. The elastic clip is made of rubber material.

7. The visual calibration target device for dynamic displacement monitoring of a steel trestle bridge according to claim 6, characterized in that: Both sides of the suspension rod are provided with connecting rods, and the lower ends of the two connecting rods are provided with support plates. A notch is opened on one side of the support plate, and bearings are installed through both sides of the inner wall of the notch. The bearings distributed along both sides are provided with the same shaft through them. The surface of the shaft is interference-fitted with the inner ring wall of any one of the bearings. A motor is provided at the outer end of the shaft. The motor has a drive shaft inside, and the end of the shaft is fixedly connected to the shaft by a coupling.

8. The visual calibration target device for dynamic displacement monitoring of a steel trestle bridge according to claim 7, characterized in that: A sleeve is provided on the surface of the shaft. A complete light-blocking plate is fixedly installed on one side of the outer ring wall of the sleeve. A semi-transparent light-blocking plate is fixedly installed on the other end of the outer ring wall of the sleeve away from the complete light-blocking plate. Several light-transmitting holes are opened on the surface of the semi-transparent light-blocking plate.

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