Gravity dam crest three-way displacement laser vision monitoring device capable of automatically leveling

Abstract

The utility model discloses a gravity dam crest three-direction displacement laser vision monitoring device capable of automatically leveling, which comprises a plurality of leveling assemblies respectively arranged on different dam sections, each leveling assembly comprises an automatic leveling support, each automatic leveling support comprises a fixed support, a first rotating shaft is erected on each fixed support along the upstream and downstream direction, and a second rotating shaft is erected on each fixed support along the upstream and downstream direction. A second rotating shaft which can rotate along with the rotation of the first rotating shaft is arranged on the first rotating shaft in a penetrating manner in the dam axis direction; a laser ranging device and a laser receiving device are respectively fixed at two ends of the second rotating shaft; the laser ranging device is used for emitting laser to the laser receiving device on the adjacent leveling assembly; and a counterweight body for keeping the two ends of the second rotating shaft horizontal is also arranged. The automatic leveling device has an automatic leveling function, and avoids the conditions that the laser beam is not horizontal and the laser receiving device is not vertical when the gravity dam displaces; the device is simple and reliable in structure, does not need to depend on a complex mechanical structure, and is accurate in measurement without deviation.

Description

Technical Field

[0001] This utility model relates to a dam crest displacement monitoring device, and more particularly to a gravity dam crest three-dimensional displacement laser visual monitoring device that can automatically level the dam crest. Background Technology

[0002] Gravity dams are among the most common hydraulic structures. They rely on their own weight for stability and incorporate transverse joints between dam sections to ensure independent operation of each section. When subjected to severe loads such as dam weight and water thrust, the dam may experience settlement, downstream sliding, or the opening of transverse joints. Displacement changes at the dam crest directly reflect the overall stability and load response of the dam structure. Continuous monitoring can promptly detect abnormal displacement signals induced by sudden changes in water level, temperature stress, foundation settlement, or material aging, effectively identifying potential risks.

[0003] Traditional methods for monitoring the displacement of gravity dam crests include displacement gauges, hydrostatic levels, and total stations. These methods suffer from problems such as complex equipment structures, high failure rates, inconvenient observation, and the need for manual intervention. Therefore, based on the structural characteristics of gravity dams, this paper proposes an automated method for monitoring dam crest displacement that is simple to use and convenient to observe, which has significant practical value. Utility Model Content

[0004] Purpose of the utility model: The purpose of this utility model is to provide a laser visual monitoring device for the three-dimensional displacement of the top of a gravity dam that is simple in structure, convenient to observe, and can be automatically leveled.

[0005] Technical Solution: The automatic leveling gravity dam crest displacement laser visual monitoring device of this utility model includes several leveling components respectively installed on different dam sections. Each leveling component includes an automatic leveling bracket, which includes a fixed bracket arranged in a direction parallel to the dam axis. A first rotating shaft is mounted on the fixed bracket in the upstream and downstream direction. A second rotating shaft, which is along the dam axis and can rotate with the first rotating shaft, passes through the first rotating shaft. Both the first and second rotating shafts can rotate freely in planes perpendicular to their respective axes. In the leveling components located on dam sections not at the edge, a laser ranging device and a laser receiving device, which can rotate with the second rotating shaft, are respectively fixed at both ends of the second rotating shaft. In the leveling components located on dam sections at the edge, at least one end of the second rotating shaft is fixed with a laser ranging device or a laser receiving device, which can rotate with the second rotating shaft. The laser ranging device is used to emit laser light to the laser receiving device on the adjacent leveling component. A counterweight is also provided to keep the two ends of the second rotating shaft horizontal.

[0006] The automatic leveling support includes two parallel fixed supports arranged at the top of the dam along the direction parallel to the dam axis.

[0007] The first and second rotating shafts are orthogonal, with the second rotating shaft passing through the center of the first rotating shaft. The fixed bracket and the two orthogonal rotating shafts in the automatic leveling bracket keep the laser emitting and receiving devices vertical; the two orthogonal rotating shafts allow the laser rangefinder and laser receiver to rotate in two orthogonal planes.

[0008] The first rotating shaft is fixed at both ends to a fixed bracket, and the part between the two ends can rotate freely. The first rotating shaft allows the monitoring device to rotate freely in a plane perpendicular to the straight line of the first rotating shaft. When the gravity dam is displaced in the dam axis direction, the first rotating shaft automatically returns to the vertical state by the weight of the device itself.

[0009] Among them, several leveling components are all on a baseline parallel to the dam axis; the line connecting the laser emission point of the laser ranging device and the center point of the laser receiving device is parallel to the dam axis.

[0010] The laser ranging device includes a laser rangefinder that emits visible light, facilitating observation of the laser's movement on a laser receiving device. The laser rangefinder measures the vertical and upstream / downstream displacement of the gravity dam by emitting laser light, and simultaneously measures the dam's axial displacement by measuring the time it takes for the laser to be emitted and reflected. The laser emitter is fixed inside a protective cover; the protective cover is a horizontally placed, open cube with its bottom surface fixed to an automatic leveling bracket, and the opening of the open cube faces the dam's axial direction. The laser emitter is fixed inside the protective cover by bolts at the bottom, and the laser emitter's axial direction is parallel to the protective cover's axial direction. The counterweight includes a first counterweight and a second counterweight; the first counterweight is suspended directly below the protective cover to ensure the laser ranging device remains vertical.

[0011] The laser receiving device includes a receiving screen near the laser rangefinder and a photosensitive sensor away from the laser rangefinder. The photosensitive sensor converts the optical signal into an electrical signal when the laser beam strikes the surface of the receiving screen, thus obtaining the displacement of the laser-irradiated point. Therefore, the laser receiving device can not only convert optical signals into electrical signals but also reflect laser light, enabling the laser rangefinder to measure displacement along the dam's axis. The receiving screen is a diffuse reflection screen. The diffuse reflection screen is a plate-like structure, vertically suspended on an automatic leveling bracket. A Cartesian coordinate system (X / Y axes) is printed on the diffuse reflection screen with a scale accuracy of 1 mm. Automatic monitoring data from the photosensitive sensor can assist manual reading correction, reducing errors.

[0012] A second counterweight is suspended below the laser receiver. With the adjustment of the first and second counterweights, the weights of the laser rangefinder and the laser receiver are equal, ensuring that the weights on both sides of the rotating shaft parallel to the dam axis are equal and remain horizontal, thus guaranteeing that the laser rangefinder and the laser receiver can always remain vertical.

[0013] Specifically, the devices on the crest of each dam section should be arranged on a baseline parallel to the dam axis. Furthermore, the line connecting the laser emission point of the laser rangefinder and the center point of the receiving screen of the laser receiving device should be parallel to the dam axis. This ensures that, when the gravity dam does not experience displacement or deformation, the laser emitted by each set of laser rangefinders will illuminate the center point of the receiving screen.

[0014] The upstream and downstream displacement and vertical displacement of the gravity dam are measured by the coordinate change of the laser irradiation point on the laser receiving device. The X-axis direction is the upstream and downstream displacement, and the Y-axis direction is the vertical displacement. The displacement of the dam axis is measured by the ranging function of the laser rangefinder.

[0015] Beneficial effects: Compared with the prior art, this utility model achieves the following significant effects:

[0016] (1) The automatic leveling bracket in each leveling component consists of two orthogonally arranged rotating shafts and a fixed bracket, which can realize the free rotation of the device in two orthogonal planes. When the gravity dam is displaced, the dam top is no longer horizontal. The automatic leveling bracket can rely on gravity and the assistance of the counterweight to keep the whole device in a vertical state, so that the laser emitted by the laser ranging device is always horizontal and the laser receiving device is always vertical, ensuring that the laser is perpendicular to the laser receiving device. The settlement, upstream and downstream displacement and relative displacement of the dam axis of adjacent dam sections are obtained by relying on the position change of the laser ranging device on the laser receiving device in the adjacent leveling components and the change of the measured value obtained by laser ranging. The displacement of each dam section is obtained by the method of accumulating segment by segment. Therefore, this utility model has the advantages of accurate measurement without deviation, simple and reliable structure and convenient observation.

[0017] (2) The automatic leveling bracket has an automatic leveling function, which avoids the situation where the laser beam is not horizontal and the laser receiving device is not vertical when the gravity dam is displaced; and the automatic leveling device has a simple and reliable structure and does not rely on a complex mechanical structure.

[0018] (3) The laser receiving device integrates visualization and automated monitoring functions by integrating a photosensitive sensor next to the diffuse reflection screen. While achieving multiple functions, the overall structure is relatively simple and does not have an overly complex design, which reduces the cost and maintenance difficulty of the device and makes it easy to install and use in different scenarios.

[0019] (4) The laser receiving device of this utility model is seamlessly connected with the laser ranging device in the adjacent leveling component, and there is no gap. This fundamentally eliminates the accumulation of measurement errors that may be caused by gaps between devices. In the continuous displacement measurement process, the accurate data of the previous measurement cycle can be transmitted to the next measurement cycle without loss, ensuring the continuity and accuracy of the entire measurement process. This makes the cumulative measurement results always highly accurate, providing reliable and unbiased measurement data for displacement monitoring.

[0020] (5) The combination of visualization and automation in laser receiving devices can effectively verify data, improve the accuracy and reliability of measurements, and has obvious advantages in troubleshooting. It can quickly locate problems and improve the maintenance efficiency and stability of the device. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0022] Figure 2 This is a structural diagram of the automatic leveling device of this utility model;

[0023] Figure 3 This is a schematic diagram illustrating the displacement measurement principle of this utility model. Detailed Implementation

[0024] The technical solution of this utility model will be further described below with reference to the accompanying drawings.

[0025] like Figure 1 , 2 As shown, this utility model provides a laser vision-based dam crest displacement monitoring device that can automatically level the dam crest, arranged on the dam crest. It includes several leveling components respectively installed on different dam sections. Each leveling component includes an automatic leveling bracket 4, which includes a fixed bracket 401 arranged parallel to the dam axis. A first rotating shaft 402 is mounted on the fixed bracket 401 along the upstream and downstream direction. A second rotating shaft 403, which rotates along the dam axis and can rotate with the first rotating shaft 402, passes through the first rotating shaft 402. Both the first rotating shaft 402 and the second rotating shaft 403 can be adjusted. The components are designed to rotate freely in their respective planes. In the leveling assembly located on the non-edge section of the dam, the two ends of the second rotating shaft 403 are respectively fixed with a laser ranging device and a laser receiving device 3 that can rotate with the second rotating shaft 403. In the leveling assembly located on the edge section of the dam, at least one end of the second rotating shaft 403 is fixed with a laser ranging device or a laser receiving device 3 that can rotate with the second rotating shaft 403. The laser ranging device is used to emit laser light to the laser receiving device 3 on the adjacent leveling assembly. A counterweight is also provided to keep the two ends of the second rotating shaft 403 horizontal.

[0026] This utility model relates to a leveling assembly for a dam section not located at its edge. The assembly includes a laser rangefinder 1, a protective cover 2, a laser receiver 3, an automatic leveling bracket 4, and counterweights. The counterweights include a first counterweight 5 and a second counterweight 6. The laser rangefinder 1 emits visible light, facilitating observation of laser movement on the laser receiver. The laser rangefinder 1 is installed inside the protective cover 2, which is fixed to the automatic leveling bracket 4. The laser receiver 3 is also fixed to the automatic leveling bracket 4. The first counterweight 5 is suspended directly below the center point of the protective cover 2, and the second counterweight 6 is suspended directly below the laser receiver 3. The automatic leveling bracket 4 is fixed to the top of the dam.

[0027] This invention calculates the displacement of the dam crest of each dam segment by measuring and accumulating the displacements of adjacent gravity dam crests. Therefore, among several laser rangefinders 1 and laser receivers 3, the laser rangefinders 1 of the later dam segment and the laser receivers 3 of the earlier dam segment can be considered as a group of displacement monitoring devices. The laser rangefinders 1 and laser receivers 3 at the top of the same dam segment are installed on the same bracket 4, and several groups of devices are arranged on a baseline parallel to the dam axis at the top of the gravity dam. This ensures that when the gravity dam has not yet shifted at the beginning of the installation, the lasers emitted by each group of laser rangefinders 1 are all on the same straight line and illuminate the center position of the laser receiver 3 in the same group.

[0028] Two fixed supports 401 are provided, arranged at the top of the dam along a direction parallel to the dam axis. The two ends of the first rotating shaft 402 are fixed to the fixed supports 401, while the middle section is free to rotate, allowing the device to rotate freely in a plane perpendicular to the line containing the first rotating shaft 402. The second rotating shaft 403 is arranged at the center of the first rotating shaft 402 and is orthogonal to it. The middle section of the second rotating shaft 403 is fixed to the middle section of the first rotating shaft 402, and both ends of the second rotating shaft 403 are free to rotate, allowing the device to rotate freely in a plane perpendicular to the line containing the second rotating shaft 403. Furthermore, the first counterweight 5 and the second counterweight 6 ensure that the weight suspended at both ends of the second rotating shaft 403 is equal, allowing the second rotating shaft 403 to remain horizontal. Ultimately, this ensures that the laser emitted by the laser rangefinder 1 is always horizontal, and the laser receiving device 3 is always vertical.

[0029] The laser receiving device includes a receiving screen near the laser rangefinder and a photosensitive sensor away from the laser rangefinder. The photosensitive sensor converts the optical signal into an electrical signal when the laser beam 503 illuminates the surface of the diffuse reflection screen, thus determining the displacement of the laser-illuminated point 502. Therefore, the laser receiving device not only converts optical signals into electrical signals but also reflects the laser beam, enabling the laser rangefinder to measure displacement along the dam's axis. The receiving screen is a diffuse reflection screen. The diffuse reflection screen is a plate-like structure, vertically suspended on an automatic leveling bracket. A Cartesian coordinate system (X / Y axes) is printed on the diffuse reflection screen with a scale accuracy of 1 mm. Automatic monitoring data from the photosensitive sensor can assist manual reading corrections, reducing errors.

[0030] The measurement principle of the device is as follows Figure 3 As shown, since the laser receiving device 3 is a diffuse reflection screen, the laser irradiation point 502 can be seen with the naked eye. Furthermore, the screen has markings, allowing the displacement of the laser irradiation point to be read visually. When the laser beam 503 irradiates the surface of the receiving screen, the photosensitive sensor converts the light signal into an electrical signal, which also provides information about the displacement of the laser irradiation point 502.

[0031] In multiple sections of a gravity dam, this invention measures from the left bank to the right bank. Except for the left bank where only a laser receiver is installed on the dam crest and the right bank where only a laser rangefinder is installed, the remaining dam sections require both laser rangefinders and laser receivers on their crests. In adjacent dam sections, the laser rangefinder on the right dam section and the laser receiver on the left dam section are in the same group, allowing for the measurement of the relative displacement of the right dam section relative to the left dam section.

[0032] This invention measures the upstream and downstream displacement and vertical displacement of a gravity dam by measuring the offset of the projection point 502 of the laser rangefinder 1 on the laser receiving device 3 in the same group. The displacement along the dam's axis is measured using the laser ranging function of the laser rangefinder 1. Before displacement of the gravity dam, the laser beam 503 emitted by the laser rangefinder 1 illuminates the center position 501 of the laser receiving device 3 in the same group. After displacement of the dam, the projection point 502 of the laser beam 503 emitted by the laser rangefinder 1 on the laser receiving device 3 shifts.

[0033] The following describes the process of obtaining the displacement of each dam segment using the device of this invention through a segment-by-segment accumulation method:

[0034] For the i-th group of n displacement monitoring devices, the horizontal offset value of laser point 502 is denoted as x. i This refers to the upstream and downstream displacement value of dam segment i relative to dam segment i-1. The vertical offset value of laser point 502 is denoted as y. iThis represents the vertical displacement of dam segment i relative to dam segment i-1. After the laser beam 503 is perpendicularly incident on the laser receiving device 3 in the same group, one beam of the diffusely reflected laser will always be reflected back to the laser rangefinder. The laser rangefinder can accurately measure the time from emission to return after reflection, thereby accurately measuring the distance from laser rangefinder 1 to the laser receiving device 3 in the same group. The measured value of the laser rangefinder is denoted as z. i When the dam has not shifted, the laser ranging measurement value is z0, i.e., Δz. i =z i -z0 represents the displacement of dam segment i relative to dam segment i-1 along the dam axis. The upstream and downstream displacement values ​​X of dam segment i are also represented. i Settlement displacement value Y i dam axis displacement value Z i The calculation formulas are as follows:

[0035]

Claims

1. An automatic leveling three-dimensional displacement laser vision monitoring device for the crest of a gravity dam, characterized in that, The system includes several leveling components installed on different sections of the dam. Each leveling component includes an automatic leveling bracket (4). The automatic leveling bracket (4) includes a fixed bracket (401) installed along the direction parallel to the dam axis. A first rotating shaft (402) is mounted on the fixed bracket (401) along the upstream and downstream direction. A second rotating shaft (403) is threaded through the first rotating shaft (402) along the dam axis and can rotate with the rotation of the first rotating shaft (402). Both the first rotating shaft (402) and the second rotating shaft (403) can rotate freely in their respective planes. The system is located on non-side sections. In the leveling assembly on the dam section at the edge, a laser ranging device and a laser receiving device (3) that can rotate with the second rotating shaft (403) are respectively fixed at both ends of the second rotating shaft (403); in the leveling assembly on the dam section at the edge, at least one end of the second rotating shaft (403) is fixed with a laser ranging device or a laser receiving device (3) that can rotate with the second rotating shaft (403); the laser ranging device is used to emit laser to the laser receiving device (3) on the adjacent leveling assembly; a counterweight is also provided to keep both ends of the second rotating shaft (403) horizontal.

2. The automatically leveling gravity dam crest three-dimensional displacement laser visual monitoring device according to claim 1, characterized in that, The first rotating shaft (402) is fixed at both ends to the fixed bracket (401), and the part between the two ends can rotate freely. When the gravity dam is displaced in the dam axis direction, it can automatically return to the vertical state by its own weight.

3. The automatically leveling gravity dam crest three-dimensional displacement laser visual monitoring device according to claim 1, characterized in that, The laser receiving device (3) is a plate-shaped structure and is vertically suspended on the automatic leveling bracket (4).

4. The self-leveling, gravity dam crest, three-dimensional displacement, laser vision monitoring device of claim 1, wherein, The laser receiving device (3) includes a receiving screen on the side close to the laser ranging device and a photosensitive sensor on the side away from the laser ranging device. The photosensitive sensor is used to convert the optical signal into an electrical signal when the laser beam (503) irradiates the surface of the receiving screen, thereby obtaining the displacement of the laser irradiation point (502).

5. The automatically leveling gravity dam crest three-dimensional displacement laser visual monitoring device according to claim 4, characterized in that, The receiving screen is a diffuse reflection screen.

6. The automatically leveling gravity dam crest three-dimensional displacement laser visual monitoring device according to claim 1, characterized in that, The laser ranging device includes a laser rangefinder (1), which emits visible light.

7. The automatically leveling gravity dam crest three-dimensional displacement laser visual monitoring device according to claim 6, characterized in that, The laser rangefinder (1) is fixed inside the protective cover (2), and the protective cover (2) is fixed on the automatic leveling bracket (4).

8. The self-leveling, gravity dam crest, three-dimensional displacement, laser vision monitoring device of claim 1, wherein, The line connecting the laser emission point of the laser ranging device and the center point of the laser receiving device (3) is parallel to the dam axis.

9. The self-leveling, gravity dam crest, three-dimensional displacement, laser vision monitoring device of claim 1, wherein, The second shaft (403) passes through the center of the first shaft (402).

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