CN-121978707-A - Dam access door detection operation method

CN121978707ACN 121978707 ACN121978707 ACN 121978707ACN-121978707-A

Abstract

The invention discloses a dam access door detection operation method, and belongs to the technical field of intelligent operation and maintenance of water conservancy. After the rapid door is closed, the water flow passage is emptied and the access door is closed, the tethered spherical unmanned aerial vehicle is lowered through the vent hole at the dam crest to enter the water flow passage, collaborative detection is performed, leakage confidence is calculated based on specular reflection, wetting area and gravity strips, shrinkage cracks and erosion damage are distinguished by texture anisotropy, and risk enhancement factors are superimposed on leakage crossing a metal-rubber interface. The running process dynamically adjusts the lowering speed and the cable tension according to the local curvature of the vent hole, and adopts a sectional lifting strategy with self-adaptive accumulated curvature during recycling. The invention solves the problems of the curved duct passing, leakage misjudgment, unclear maintenance priority and the like, and realizes safe, accurate and full-automatic detection.

Inventors

GAN HUIMIN
YAO YONGHUAN
WANG CHENJIE
XIONG JIAN
XIAO PENG
HU JUN
WU LIGUI
LIU LIANWEI
QIU TAO
LI YAJUN
LI WEIXIAN
TONG YING

Assignees

中国长江电力股份有限公司

Dates

Publication Date: 20260505
Application Date: 20260119

Claims (10)

1. The dam access door detection operation method is characterized by adopting an integrated detection system, wherein the integrated detection system comprises an operation platform (10), a spherical unmanned aerial vehicle (30) is connected to the operation platform (10) through a retractable cable (20), and the spherical unmanned aerial vehicle (30) is provided with a camera and a laser radar; the detection operation method comprises the following steps: s1, closing a quick door (4), and discharging water on the downstream side of a water flow channel (3); S2, closing an access door (5), and opening a quick door (4); s3, deploying the integrated detection system on a dam top (2) of the dam body (1), and enabling the spherical unmanned aerial vehicle (30) to be positioned right above an inlet of the vent hole (6); S4, based on a pre-acquired three-dimensional model of the vent hole (6), the control cable (20) is released in a variable speed strategy, so that the spherical unmanned aerial vehicle (30) smoothly descends into the water flow channel (3) along the inner cavity of the bent vent hole (6); S5, carrying a camera and a laser radar on the spherical unmanned aerial vehicle (30) to carry out cooperative detection operation on the access door (5) and the water channel (3); s6, after detection is completed, the spherical unmanned aerial vehicle (30) is recovered along the original path.
2. A dam access door detection method according to claim 1, wherein after the spherical unmanned aerial vehicle (30) enters the water flow channel (3), cooperative detection is performed including: a. the detection of access door leakage, namely, utilizing visible light and polarization imaging to scan the surface of an access door (5), identifying a strip-shaped wet spot with a specular reflection water film, continuous water drops or from top to bottom, and carrying out leakage judgment; b. Detecting the surface state of an access door, namely fusing laser point cloud and an image, and identifying metal rust bulge and water stopping rubber void; c. And (3) detecting the surface of the runner concrete, namely transversely scanning the inner wall of the adjacent concrete, and identifying shrinkage cracks, erosion pits or calcium precipitation.
3. A dam access door detection operation method according to claim 1, wherein in S4, the larger the local curvature of the vent hole (6) is, the larger the radius of the spherical unmanned aerial vehicle (30) is, the smaller the safety clearance is, the higher the blocking risk is, and when the blocking risk exceeds a threshold value, the lowering speed is automatically reduced and the tension of the cable (20) is increased, so that the effective throughput of the spherical unmanned aerial vehicle (30) in a curved channel is improved.
4. A method of dam access door detection operation according to claim 1 or 3, wherein the maximum allowable lowering speed of the spherical unmanned aerial vehicle (30) in the vent hole (6) decays exponentially with increasing local curvature, ensuring a significant deceleration in the sharp bend area to maintain the running stability.
5. A dam access door detection method according to claim 1, wherein in S4, the lateral friction force of the cable (20) on the current bending section is estimated in real time, the friction force is proportional to the cable tension and the total curvature integral value of the bending section, and if the estimated friction force exceeds a safety threshold, the cable (20) is suspended and reciprocally wound and unwound for a small margin to release the accumulated stress.
6. The dam access door detection operation method according to claim 2, wherein leakage confidence is calculated by considering specular reflection intensity, wetted area ratio and whether the wet area is distributed in a stripe shape along the gravity direction, and if the confidence reaches a preset high credibility threshold, true leakage is judged.
7. A method of dam access door testing as set forth in claim 6 wherein risk priority scores for areas of leakage across the metal-rubber interface are further overlaid on the base leakage confidence level with an enhancement factor proportional to the length of the intersection of the defect and the interface to highlight the severity of seal failure type leakage.
8. A dam access door detection operation method according to claim 2, wherein when detecting concrete in the water channel (3), the degree of texture anisotropy is calculated based on the second derivative characteristic of the image of the damaged area, if the degree of anisotropy is low and distributed in a net shape, it is judged that the crack is dry shrinkage, and if the degree of anisotropy is high and distributed in a radial shape, it is judged that the damage is erosion.
9. A dam access door detection operation method according to claim 2, wherein if the surface rust area ratio of the access door (5) exceeds a rust area threshold dynamically adjusted based on service life, or the adjacent concrete crack density exceeds a corresponding service life related threshold, respectively generating targeted maintenance suggestions.
10. A dam access door detection method according to claim 1, wherein in S6, a sectional pulling strategy is adopted in the recovery stage, and the suspension time of each section is dynamically prolonged according to the accumulated curvature of the section and all the previous curved sections, so that a longer cable relaxation time is given in a high curvature accumulation area, and the flexible cable (20) naturally fits the hole wall of the ventilation hole (6) under the action of gravity.

Description

Dam access door detection operation method Technical Field The invention relates to the technical field of intelligent operation and maintenance of hydraulic and hydroelectric engineering, in particular to a dam access door detection operation method. Background In large-scale water-conservancy junction, such as ship lock, flood discharge gate, hydropower station diversion system, the access door is the key structure of guarantee equipment maintenance and emergent shutoff. Traditional detection relies on manual entry water flow channel visual inspection, and has the problems of high risk, low efficiency, multiple blind areas and the like. In recent years, unmanned aerial vehicle inspection is gradually applied, but under the water conservancy scene, the problems that the first vent hole and the plurality of vent holes are downwards bent concrete channels, such as J-shaped, are not straight-line through and cannot be penetrated by a common unmanned aerial vehicle, the second vent hole and the water channels are closed spaces, wireless signal attenuation is serious, and communication and cruising of the unmanned aerial vehicle with battery power supply are difficult to ensure. At present, although a tethered unmanned aerial vehicle is used for power inspection, the tethered unmanned aerial vehicle works in an open space above the ground, and no truly feasible scheme exists at present for the operation of detecting a dam access door. To this end, we propose a dam access door inspection operation method of the present application. Disclosure of Invention The invention aims to provide a dam access door detection operation method, which is used for detecting a dam access door through a vent hole. In order to achieve the above purpose, the application provides a dam access door detection operation method, which adopts an integrated detection system, wherein the integrated detection system comprises an operation platform, a spherical unmanned aerial vehicle is connected to the operation platform through a retractable cable, and the spherical unmanned aerial vehicle is provided with a camera and a laser radar; the detection operation method comprises the following steps: s1, closing a quick door, and discharging water on the downstream side of a water flow path; s2, closing an access door and opening a quick door; s3, deploying the integrated detection system at the dam crest of the dam body, and enabling the spherical unmanned aerial vehicle to be positioned right above the inlet of the vent hole; S4, based on a pre-acquired three-dimensional model of the vent hole, the control cable is released in a variable speed strategy, so that the spherical unmanned aerial vehicle smoothly descends into the water flow path along the bent vent hole inner cavity; s5, carrying a camera and a laser radar on the spherical unmanned aerial vehicle to carry out collaborative detection operation on the access door and the water channel; S6, after detection is completed, the spherical unmanned aerial vehicle is recovered along the original path. After the spherical unmanned aerial vehicle enters the water flow channel, the cooperative detection comprising the following steps is executed: a. The detection of access door leakage, namely, scanning the surface of the access door by utilizing visible light and polarization imaging, identifying a strip-shaped wet spot with a mirror surface reflective water film, continuous water drops or from top to bottom, and judging leakage; b. Detecting the surface state of an access door, namely fusing laser point cloud and an image, and identifying metal rust bulge and water stopping rubber void; c. And (3) detecting the surface of the runner concrete, namely transversely scanning the inner wall of the adjacent concrete, and identifying shrinkage cracks, erosion pits or calcium precipitation. In S4, the larger the local curvature of the vent hole and the larger the radius of the spherical unmanned aerial vehicle, the smaller the safety clearance and the higher the blocking risk are, and when the blocking risk exceeds a threshold value, the lowering speed is automatically reduced and the cable tension is increased so as to improve the effective traffic capacity of the spherical unmanned aerial vehicle in a curved channel. The maximum allowable drop-off speed of the spherical drone in the vent hole decays exponentially with increasing local curvature, ensuring a significant drop-off in the sharp bend area to maintain the ride stability. In S4, the lateral friction force of the cable on the current bending section is estimated in real time, the friction force is proportional to the cable tension and the total curvature integral value of the bending section, and if the estimated friction force exceeds a safety threshold, the cable is suspended to be released and is reciprocally wound and unwound for a small extent to release the accumulated stress. And calculating leakage confidence coefficient of the wet