Method for detecting completed bridge pile foundation based on unmanned aerial vehicle

Abstract

The invention relates to the field of pile foundation construction engineering, in particular to a method for detecting a completed bridge pile foundation based on an unmanned aerial vehicle. The method specifically comprises the following steps: S1, determining a detection area according to a pile foundation area; s2, arranging a plurality of image control points and a plurality of check points in the detection area at intervals; s3, providing an unmanned aerial vehicle, installing a camera on the lower side of the unmanned aerial vehicle, and formulating a route of the unmanned aerial vehicle; s4, enabling the unmanned aerial vehicle to fly along the set route and shooting the image control points; s5, after the unmanned aerial vehicle flies and shoots, a three-dimensional model is established for the pile foundation area according to the shot image, and the three-dimensional model is output as a DOM; and S6, superposing a CAD drawing of a bridge pile foundation point position on the orthographic map DOM, and comparing the orthographic map DOM with the CAD drawing to check whether the pile foundation design positions are consistent or not. The method has the beneficial effects that the unmanned aerial vehicle is used for collecting image data of a pile foundation area in a detection area, compared with a traditional total station measurement method, non-contact observation is adopted, the observation range is wider, information of multiple pile foundation points can be collected at the same time, and the operation efficiency is high.

Description

Technical Field

[0001] The invention relates to the field of pile foundation construction engineering, and in particular to a method for detecting completed bridge pile foundations based on an unmanned aerial vehicle. Background Art

[0002] During the construction of pile foundation, measurement is the first step and a critical link throughout the entire construction cycle. Since most construction sites have complex conditions, the measurement results require high accuracy and are difficult to correct, high-precision pile foundation measurement plays a pivotal role in engineering construction. Traditional pile foundation positioning uses total station observation. Although this method is relatively mature, it has the disadvantages of low efficiency, poor safety, and is greatly affected by on-site environmental factors.

[0003] In recent years, with the increasing maturity of drone technology, drones have been applied to various fields. In the engineering field, drones are generally used for earthwork calculation, high slope monitoring and other applications. Drones collect data at low altitudes, and there is less human intervention during the data collection process. Using drone technology for pile foundation measurement will be more effective than traditional measurement methods.

[0004] Therefore, the present invention proposes a method for detecting completed bridge pile foundations based on unmanned aerial vehicles. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the prior art and provide a method for detecting completed bridge pile foundations based on drones, so as to solve the problems of low efficiency, poor safety and great influence of on-site environmental factors in the existing pile foundation positioning detection methods.

[0006] The present invention provides a method for detecting a completed bridge pile foundation based on an unmanned aerial vehicle, and its technical scheme is as follows: the specific method is as follows: S1: determining a detection area according to a pile foundation area, so that the pile foundation area is located within the range of the detection area; S2: arranging a plurality of image control points and a plurality of inspection points at intervals in the detection area; S3: providing an unmanned aerial vehicle, installing a camera on the lower side of the unmanned aerial vehicle, and formulating a route of the unmanned aerial vehicle, so that the route of the unmanned aerial vehicle can cover the detection area and pass directly above each of the image control points; S4: making the unmanned aerial vehicle fly along the set route and photograph the image control points; S5: after the unmanned aerial vehicle flies and photographs, establishing a three-dimensional model of the pile foundation area according to the photographed image, and outputting the three-dimensional model as an orthophoto image DOM; S6: superimposing a CAD drawing of the bridge pile foundation points on the orthophoto image DOM, comparing the orthophoto image DOM with the CAD drawing to check whether the pile foundation design position is consistent, thereby determining whether the completed bridge pile foundation meets the design requirements.

[0007] Furthermore, the image control points are arranged at the four corners of the detection area, at the midpoints of the four sides and at the midpoint of the detection area; and the check points are arranged at intervals around the pile foundation area.

[0008] Furthermore, the shooting direction of the camera below the drone is at a set angle to the ground, and the drone flies to the opposite side from the four directions of east, west, south and north of the detection area in sequence.

[0009] Furthermore, after the UAV flies to the opposite side from four directions, the camera is adjusted so that the shooting direction of the camera is perpendicular to the ground, and then the UAV is made to fly from the north side to the south side of the detection area.

[0010] Furthermore, the UAV is positioned in real time by using RTK technology to ensure the correct course.

[0011] Furthermore, the specific steps for positioning the UAV through the RTK technology are: providing a GNSS base station, setting the GNSS base station in the detection area, connecting the UAV to the GNSS base station, and connecting the GNSS base station to the satellite, so that the UAV is connected to the satellite through the GNSS base station and positioned.

[0012] Furthermore, a laser rangefinder is provided at each of the image control points, and the emission direction of the laser transmitter of the laser rangefinder is vertically upward, so that when the UAV passes directly above the image control point, the laser rangefinder can detect the UAV, and further indirectly determine whether the UAV's course is correct.

[0013] Furthermore, after the drone flies according to the set route, the image taken by the camera on the lower side of the drone is imported into the Context Capture software, and the pile foundation area is 3D modeled through steps such as tile segmentation, puncture points, and 3D reconstruction, and the 3D model is output as an orthophoto map DOM.

[0014] Furthermore, after the orthophoto DOM is exported, the orthophoto DOM is imported into ArcGIS, and geometric correction, rotation, and splicing are performed. The CAD drawing of the bridge pile foundation point and diameter is loaded in the CAD, and the orthophoto DOM is loaded as the base map. The CAD drawing and the DOM drawing are matched through coordinate matching. The pile foundation position in the DOM drawing is compared with the pile foundation design position in the CAD drawing. The actual distance between the two is measured using the measurement function of the CAD, so as to determine the error value of the completed bridge pile foundation.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The drone is used to collect image data of the pile foundation area within the inspection area, and three-dimensional modeling is performed based on the collected image data to obtain the orthophoto map of the inspection area. The graphics are analyzed by superimposing the graphics to obtain the error between the design value and the actual value. Compared with the traditional total station measurement method, it adopts non-contact observation, has a wider observation range, can collect multiple pile foundation point information at the same time, and has high operation efficiency.

[0017] Compared with traditional surveying and mapping, it has the advantages of high efficiency and low risk, and the model built contains a variety of data, which is easy to apply to other engineering stages, and can visualize the data for easy observation and operation. The three-dimensional model of the top of the pile foundation established by the oblique photogrammetry of the drone can quickly, safely and comprehensively collect data on the plane position of the pile foundation, providing a new measurement method for pile foundation detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of signal transmission of the method for detecting completed bridge pile foundations based on unmanned aerial vehicles according to the present invention.

[0019] Figure 2 It is a schematic plan view of the detection area of ​​the method for detecting completed bridge pile foundations based on an unmanned aerial vehicle according to the present invention.

[0020] Figure 3 The diagram is a schematic diagram of a drone route for a method of detecting a completed bridge pile foundation using a drone according to the present invention.

[0021] Figure 4 The present invention is a workflow diagram of a method for detecting completed bridge pile foundations based on an unmanned aerial vehicle.

[0022] Legend: 1. UAV; 2. Laser rangefinder; 3. Satellite; 4. Ground; 5. Checkpoint; 6. Pile foundation area; 7. Inspection area; 8. Image control point; 9. GNSS base station. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0024] See also Figure 1The present invention provides a method for detecting completed bridge pile foundations based on drones, which solves the problems of low efficiency, poor safety, and great influence of on-site environmental factors in existing pile foundation positioning detection methods. The drone is used to collect image data of the pile foundation area within the detection area, and three-dimensional modeling is performed based on the collected image data to obtain an orthophoto map within the detection area, and the graphics are analyzed by superposition of graphics to obtain the error between the design value and the actual value. Compared with the traditional total station measurement method, non-contact observation is adopted, and the observation range is wider. Multiple pile foundation point information can be collected at the same time, and the operation efficiency is high. Compared with traditional surveying and mapping, it has the advantages of high efficiency and low risk, and the constructed model contains a variety of data, which is convenient for application in other engineering stages, and the data can be visualized for easy observation and operation. The three-dimensional model of the top of the pile foundation established by the drone using oblique photogrammetry can quickly, safely and comprehensively collect data on the plane position of the pile foundation, providing a new measurement method for pile foundation detection.

[0025] A method for detecting a completed bridge pile foundation based on a drone according to the present invention is described below in conjunction with the accompanying drawings.

[0026] See also Figure 1 , showing a schematic diagram of signal transmission of the method for detecting completed bridge pile foundations based on a drone according to the present invention. Figure 2 , showing a schematic diagram of the detection area of ​​the method for detecting a completed bridge pile foundation based on a drone according to the present invention. Figure 1 and Figure 2 , a method for detecting a completed bridge pile foundation based on a drone is described in the present invention.

[0027] like Figure 1 and Figure 2 As shown, a method for detecting a completed bridge pile foundation based on a drone of the present invention is specifically as follows: S1: determining a detection area 7 according to a pile foundation area 6, so that the pile foundation area 6 is located within the range of the detection area 7; S2: arranging a plurality of image control points 8 and a plurality of inspection points 5 at intervals in the detection area 7; S3: providing a drone 1, installing a camera on the lower side of the drone 1, and formulating a route for the drone 1, so that the route of the drone 1 can cover the detection area 7 and pass directly above each of the image control points 8; S4: making the drone 1 fly along the set route and photograph the image control points 8; S5: after the drone 1 flies and photographs, establishing a three-dimensional model of the pile foundation area 6 according to the photographed image, and outputting the three-dimensional model as an orthophoto map DOM; S6: superimposing a CAD drawing of the bridge pile foundation points on the orthophoto map DOM, comparing the orthophoto map DOM with the CAD drawing to check whether the pile foundation design position is consistent, thereby determining whether the completed bridge pile foundation meets the design requirements.

[0028] Specifically, by setting the checkpoint 5, when establishing the three-dimensional model diagram of the pile foundation area 6, the coordinate system of the three-dimensional model of the pile foundation area 6 can be checked through the checkpoint 5 to determine whether the coordinate system is accurate; by setting the image control point 8, after detecting that the coordinate system is inaccurate, the coordinate system can be corrected through the image control point 8.

[0029] In a preferred embodiment, when the route of the drone 1 is formulated, the aerial survey altitude, overlap, etc. are also formulated.

[0030] In a specific implementation, the image control points 8 are arranged at the four corners of the detection area 7 , at the midpoints of the four sides, and at the midpoint of the detection area 7 ; and the check points 5 are arranged at intervals around the pile foundation area 6 .

[0031] In a specific embodiment, the shooting direction of the camera below the drone 1 is at a set angle to the ground, and the drone 1 flies to the opposite side from the four directions of east, west, south and north of the detection area 7 in sequence.

[0032] In a specific implementation, after the drone 1 flies to the opposite side from four directions, the camera is adjusted so that the shooting direction of the camera is perpendicular to the ground, and then the drone 1 flies from the north side to the south side of the detection area 7.

[0033] In a preferred embodiment, the shooting angle of the camera on the lower side of the drone 1 is set at an angle of 45° to the ground.

[0034] In a specific implementation, the drone 1 performs real-time positioning through RTK technology to ensure the correct course.

[0035] In a specific embodiment, the specific steps for positioning the UAV 1 through the RTK technology are: providing a GNSS reference station 9, setting the GNSS reference station 9 in the detection area 7, connecting the UAV 1 to the GNSS reference station 9, and connecting the GNSS reference station 9 to the satellite 3, so that the UAV 1 is connected to the satellite 3 through the GNSS reference station 9 and positioned.

[0036] In a specific embodiment, a laser rangefinder 2 is provided at each of the image control points 8, and the emission direction of the laser transmitter of the laser rangefinder 2 is vertically upward, so that when the UAV 1 passes directly above the image control point 8, the laser rangefinder 2 can detect the UAV 1, and then indirectly determine whether the course of the UAV 1 is correct.

[0037] More specifically, the RTK surveying instrument adopts real-time dynamic carrier phase differential technology, which is a differential method for processing the carrier phase observations of two measuring stations in real time, and sends the carrier phase collected by the base station to the receiver for calculating the difference and settling the coordinates.

[0038] In a specific implementation, an inertial navigation system is provided inside the drone 1 to determine the attitude information of the drone 1 under control.

[0039] In a specific implementation, the drone 1 is a consumer-grade single-lens drone.

[0040] In a specific embodiment, after the drone 1 flies according to the set route, the image taken by the camera on the lower side of the drone 1 is imported into the Context Capture software, and the pile foundation area 6 is three-dimensionally modeled through tile segmentation, punctation, and three-dimensional reconstruction steps, and the three-dimensional model is output as an orthophoto map DOM.

[0041] In a specific implementation, after the orthophoto DOM is exported, the orthophoto DOM is imported into ArcGIS, and geometric correction, rotation, and splicing are performed. The CAD diagram of the bridge pile foundation point and diameter is loaded in CAD, and the orthophoto DOM is loaded as the base map. The CAD diagram and the DOM diagram are matched by coordinate matching, and the pile foundation position in the DOM diagram is compared with the pile foundation design position in the CAD diagram to see if they are consistent. The actual distance between the two is measured by using the measurement function of CAD. After the DOM diagram and the CAD diagram are superimposed, the difference between the two can be intuitively obtained by comparison, thereby determining the plane position relationship between the design value and the actual value, determining the plane position of the completed pile foundation, and thus determining the error value of the completed bridge pile foundation.

[0042] The following is a detailed description of the construction process of the present invention based on unmanned aerial vehicle (UAV) to detect the completed bridge pile foundation.

[0043] Based on the preliminary data collation and on-site survey results, the scope of the survey area is determined, the aerial survey route, aerial survey height, overlap, etc. are formulated, image control point 8 and check point 5 are arranged, and a laser rangefinder 2 is arranged at image control point 8.

[0044] The drone 1 used is a consumer-grade single-lens drone, and the vertical angle and four groups of angles to be collected should be 45°. The flight direction of the drone 1 is east, south, west, and north in turn.

[0045] The images collected by aerial survey are imported into Context Capture software, and three-dimensional modeling is performed through steps such as tile segmentation, punctum points, and three-dimensional reconstruction. The three-dimensional model of the bridge pile foundation area 6 is established by oblique photogrammetry of UAV 1, and the orthophoto map DOM is output.

[0046] Use ArcGIS to process the orthophoto DOM (geometric correction, rotation, and stitching), load the CAD drawing of the bridge pile foundation points and diameters into CAD, load the DOM map as the base map, match the two through coordinate matching, compare the pile foundation position in the DOM map with the pile foundation design position in the CAD map, and use the CAD measurement function to measure the actual distance between the two.

[0047] The present invention is described in detail above in conjunction with the embodiments of the accompanying drawings. A person skilled in the art can make various variations of the present invention according to the above description. Therefore, certain details in the embodiments should not constitute a limitation of the present invention, and the scope of protection of the present invention shall be defined by the scope of the attached claims.

Claims

1. A method for detecting completed bridge pile foundations based on drones, characterized in that: The specific method is as follows: S1: determining a detection area (7) according to a pile foundation area (6), so that the pile foundation area (6) is located within the range of the detection area (7); S2: arranging a plurality of image control points (8) and a plurality of inspection points (5) at intervals in the detection area (7); S3: providing a drone (1), installing a camera on the lower side of the drone (1), and planning a route for the drone (1) so that the route of the drone (1) can cover the detection area (7) and pass directly above each of the image control points (8); S4: causing the drone (1) to fly along the set route and photograph the image control points (8); S5: After the drone (1) flies and takes photos, a three-dimensional model is established for the pile foundation area (6) according to the taken images, and the three-dimensional model is output as an orthophoto map DOM; S6: superimposing the CAD drawing of the bridge pile foundation points on the orthophoto image DOM, and comparing the orthophoto image DOM with the CAD drawing to check whether the pile foundation design positions are consistent, so as to determine whether the completed bridge pile foundation meets the design requirements.

2. The method for detecting completed bridge pile foundations based on drones according to claim 1 is characterized in that: The image control points (8) are arranged at the four corners and the midpoints of the four sides of the detection area (7) and at the midpoint of the detection area (7); the inspection points (5) are arranged at intervals around the pile foundation area (6).

3. The method for detecting completed bridge pile foundations based on drones according to claim 1 is characterized in that: The shooting direction of the camera below the drone (1) is at a set angle to the ground, and the drone (1) flies to the opposite side from the four directions of east, west, south and north of the detection area (7) in sequence.

4. The method for detecting completed bridge pile foundations based on drones according to claim 3 is characterized in that: After the drone (1) flies to the opposite side from four directions, the camera is adjusted so that the shooting direction of the camera is perpendicular to the ground, and then the drone (1) is made to fly from the north side to the south side of the detection area (7).

5. The method for detecting completed bridge pile foundations based on drones according to claim 1 is characterized in that: The drone (1) performs real-time positioning through RTK technology to ensure the correctness of the navigation path.

6. The method for detecting completed bridge pile foundations based on drones according to claim 5 is characterized in that: The specific steps of positioning the unmanned aerial vehicle (1) by using the RTK technology are as follows: providing a GNSS reference station (9), arranging the GNSS reference station (9) in the detection area (7), connecting the unmanned aerial vehicle (1) to the GNSS reference station (9), and connecting the GNSS reference station (9) to the satellite (3), thereby achieving connection and positioning of the unmanned aerial vehicle (1) with the satellite (3) through the GNSS reference station (9).

7. The method for detecting completed bridge pile foundations based on drones according to claim 6 is characterized in that: A laser rangefinder (2) is provided at each of the image control points (8), and the emission direction of the laser transmitter of the laser rangefinder (2) is vertically upward, so that when the drone (1) passes directly above the image control point (8), the laser rangefinder (2) can detect the drone (1), thereby indirectly judging whether the route of the drone (1) is correct.

8. The method for detecting completed bridge pile foundations based on drones according to claim 1 is characterized in that: After the drone (1) flies according to the set route, the image captured by the camera on the lower side of the drone (1) is imported into Context Capture software, and the pile foundation area (6) is three-dimensionally modeled through tile segmentation, punctation, and three-dimensional reconstruction, and the three-dimensional model is output as an orthophoto map DOM.

9. The method for detecting completed bridge pile foundations based on drones according to claim 8, characterized in that: After the orthophoto DOM is exported, the orthophoto DOM is imported into ArcGIS, and geometric correction, rotation, and splicing are performed. The CAD drawing of the bridge pile foundation point and diameter is loaded in CAD, and the orthophoto DOM is loaded as the base map. The CAD drawing and the DOM drawing are matched through coordinate matching. The pile foundation position in the DOM drawing is compared with the pile foundation design position in the CAD drawing. The actual distance between the two is measured using the measurement function of CAD, so as to determine the error value of the completed bridge pile foundation.

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