Method for positioning offshore structure based on unmanned aerial vehicle loading monitoring system

Abstract

The invention discloses a method for positioning the position of an offshore structure based on an unmanned aerial vehicle loading monitoring system, the unmanned aerial vehicle loading monitoring system adopts a rigid platform suspended by an unmanned aerial vehicle cluster, and the rigid platform is provided with a full-automatic tracking total station, a GPS, a double-shaft tilt angle sensor and an ultrasonic distance measuring sensor. After the unmanned aerial vehicle cluster suspends the rigid platform to the inclined sky of the offshore structure, hovering is carried out; the flight height of the unmanned aerial vehicle cluster is adjusted through data of an ultrasonic distance measuring sensor, inclination angle data is measured through a double-shaft inclination angle sensor, and the levelness of the rigid platform is further calibrated; the full-automatic tracking total station is used for measuring the horizontal angle, the vertical angle and the slant distance of the offshore structure and uploading the horizontal angle, the vertical angle and the slant distance to the upper computer, the upper computer calculates the three-dimensional coordinates of the full-automatic tracking total station according to coordinate data of the GPS, and then the three-dimensional coordinates of the center point of the offshore structure are calculated. According to the invention, positioning of the offshore structure can be realized, monitoring dead angles are avoided, and personnel risk is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicles (UAVs), and in particular to a method for locating the position of an offshore structure based on an UAV-borne monitoring system. Background Art

[0002] Offshore steel cylinder is a kind of efficient, reliable and multifunctional large-scale marine steel structure, which has great advantages in the rapid construction of offshore cofferdams and artificial islands.

[0003] Offshore steel cylinders are typically several meters above sea level. Traditionally, positioning is performed using a nearby positioning vessel. During offshore engineering monitoring, sensors are manually deployed on the object from a monitoring vessel close to the object, posing a potential safety hazard. Alternatively, monitoring equipment can be placed on the vessel, but sometimes, because the object is significantly higher than the vessel, there are blind spots. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for locating the position of offshore structures based on an unmanned aerial vehicle (UAV)-borne monitoring system in order to address the technical defects in the prior art.

[0005] The technical solution adopted to achieve the purpose of the present invention is: The present invention designs a method for locating the position of an offshore structure based on an unmanned aerial vehicle (UAV)-borne monitoring system. The UAV-borne monitoring system includes a rigid platform, a UAV cluster, a fully automatic tracking total station, a GPS, a dual-axis tilt sensor, and an ultrasonic ranging sensor. The rigid platform is an equilateral triangle, the UAV cluster is used to hoist the rigid platform, the number of UAVs in the UAV cluster is consistent with the number of corner points of the rigid platform, the fully automatic tracking total station is fixedly set at the midpoint of one side of the rigid platform, a GPS is set at the midpoint of each of the other two sides of the rigid platform, the dual-axis tilt sensor is fixedly set at the center of the rigid platform, and the ultrasonic ranging sensor is fixedly set at each corner point of the rigid platform. The following steps are involved: Step 1: After the drone cluster hoisted the rigid platform to the oblique upper part of the offshore structure, the drone hovering mode was activated; Step 2: Use the data from the ultrasonic ranging sensor to adjust the flight altitude of the drone cluster, and then adjust the inclination of the rigid platform. Use the dual-axis inclination sensor to measure the inclination data and further calibrate the horizontality of the rigid platform. Step 3: Use the fully automatic tracking total station to measure the center point of the reflector of the offshore structure P Horizontal angle , vertical angle , slope distance SAnd upload it to the host computer, which calculates the three-dimensional coordinates of the fully automatic tracking total station based on the GPS coordinate data, and then calculates the center point of the offshore structure P The three-dimensional coordinates of .

[0006] In the above technical solution, the rigid platform is made of carbon fiber material.

[0007] In the above technical solution, the GPS and the fully automatic tracking total station are on the same plane.

[0008] In the above technical solution, a backsight reflector is attached to the base of one of the GPS units to serve as the backsight point of the fully automatic tracking total station.

[0009] In the above technical solution, in step 1, the offshore structure is a steel cylinder, a cross is placed 10 to 15 cm downward from the inner opening of the steel cylinder, and a reflective sheet is attached to the center of the cross.

[0010] In the above technical solution, in step 3, the center point of the offshore structure P The three-dimensional coordinates of The calculation formula is: ; Where, To automatically track the three-dimensional coordinates of the total station, The center point of the offshore structure P The horizontal angle, The center point of the offshore structure P The vertical angle, S The center point of the offshore structure P slant distance.

[0011] In the above technical solution, the three-dimensional coordinates of the fully automatic tracking total station The calculation formula is: ; Where, is the three-dimensional coordinate of one of the GPS, is the three-dimensional coordinate of another GPS, z It is the elevation difference between GPS and fully automatic tracking total station; is the vector between the two GPSs, The calculation formula is: .

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention utilizes the high-altitude operation characteristics of UAVs. By deploying a fully automatic tracking total station, GPS positioning sensors, ultrasonic ranging sensors, and dual-axis tilt sensors on a rigid platform, it can achieve the positioning of offshore structures (such as offshore steel cylinder positioning), avoid monitoring blind spots, reduce personnel risks, and is particularly suitable for rapid measurement in complex sea areas. 2. The present invention adopts a carbon fiber composite material rigid platform, which has the characteristics of light weight and high rigidity, and is suitable for UAV lifting scenarios; 3. The method of locating the position of offshore structures based on an unmanned aerial vehicle (UAV)-borne monitoring system of the present invention is not affected by the height of the object being measured. As long as the rigid platform hoisted by the UAV is located obliquely above the object being measured and a prism or reflector is stably placed at a position on the object that is conducive to measurement, the accurate three-dimensional coordinates of the object being measured can be obtained by distance conversion. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 Shown is a schematic structural diagram of the UAV-mounted monitoring system of the present invention.

[0014] Figure 2 Shown is a schematic diagram of the distribution of GPS and fully automatic tracking total stations on the rigid platform of the UAV-borne cargo monitoring system of the present invention.

[0015] In the figure: 1-rigid platform, 2-UAV, 3-fully automatic tracking total station, 4-GPS, 5-dual-axis tilt sensor, 6-ultrasonic ranging sensor, 7-steel cylinder, 8-cross, 9-reflective sheet. DETAILED DESCRIPTION

[0016] The present invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0017] The present invention designs a method for locating the position of offshore structures, which is based on the UAV-borne monitoring system. Figure 1The unmanned aerial vehicle (UAV) cargo monitoring system includes a rigid platform 1, a UAV cluster, a fully automatic tracking total station 3, a GPS 4, a dual-axis tilt sensor 5, and an ultrasonic ranging sensor 6. The UAV cluster is used to carry the rigid platform 1. The number of UAVs 2 in the UAV cluster is consistent with the number of corner points of the rigid platform 1. The rigid platform 1 is an equilateral triangle. The fully automatic tracking total station 3 is fixedly set at the midpoint of one side of the rigid platform 1. A GPS 4 is set at the midpoint of the other two sides of the rigid platform 1. A rearview point reflector is attached to the base of one of the GPS 4s as the rearview point of the fully automatic tracking total station 3. The dual-axis tilt sensor 5 is fixedly set at the center position of the rigid platform 1, and the ultrasonic ranging sensor 6 is fixedly set at each corner point of the rigid platform 1.

[0018] Furthermore, the rigid platform 1 is made of carbon fiber composite material, which has the characteristics of light weight and high rigidity, and is suitable for drone hanging scenarios; the GPS4 adopts RTK differential technology to make the GPS4 coordinate accuracy higher, providing a reliable benchmark for the measurement of the fully automatic tracking total station 3.

[0019] The method for locating the position of offshore structures based on the above-mentioned drone-borne monitoring system is as follows: First, three drones 2 are used to suspend an equilateral triangular rigid platform 1. After the drone cluster flies obliquely above the steel cylinder 7, the drone hovering mode is enabled.

[0020] Next, the flight altitude of each drone 2 is adjusted using data from ultrasonic ranging sensors 6 located at three corners of the rigid platform 1, thereby adjusting the inclination of the rigid platform 1 to maintain its horizontality. The inclination of the rigid platform 1 is then measured using a dual-axis tilt sensor 5 fixed at the center of the rigid platform 1 to further calibrate its horizontality. GPS data and data from the fully automatic tracking total station 3 are synchronized using hardware clock synchronization or software settings. Before measuring the data from the steel cylinder 7, the fully automatic tracking total station 3 is oriented using the GPS 4, which has a rear-view reflector installed on its base, to confirm its rear-view azimuth. This confirms the orientation and provides a directional reference for subsequent measurements.

[0021] Finally, the center point of the reflector 9 on the cross 8 inside the steel cylinder 7 is measured using the fully automatic tracking total station 3. P Horizontal angle , vertical angle , slope distance S , and read the coordinate data of two GPS 4 at the same time. Since the fully automatic tracking total station 3 flies with the drone 2, the coordinate data is constantly changing in real time. In this embodiment, the coordinate data measured by GPS 4 and the horizontal angle of the steel cylinder 7 measured by the fully automatic tracking total station 3 are used. , vertical angle , slope distance S At the same time, it is uploaded to the host computer, and then the host computer calculates the coordinates of the automatic tracking total station 3 based on the coordinate data of the two GPS4, and then calculates the center point of the cross 8 inside the steel cylinder 7 P The three-dimensional coordinates of .

[0022] Reference Figure 2 , let the equilateral triangle rigid platform 1 be △ABC, and the automatic tracking total station 3 be located at the midpoint of the AB side , define two GPS as GPS i and GPS j , the GPS i Located at the midpoint of side BC , GPS j Located at the midpoint of CA side , the triangle is counterclockwise, M c In vector Left side.

[0023] The GPS i and GPS j The midpoint of the side M a 、M b Vector The calculation formula is: ; Where, and GPS i and GPS j The three-dimensional coordinates of .

[0024] The three-dimensional coordinates of the fully automatic tracking total station 3 The calculation formula is: ; Where, For GPS i and GPS j The midpoint of the side M a 、M b vector, For GPS i The three-dimensional coordinates of For GPS j The three-dimensional coordinates of . z is the elevation difference between GPS 4 and the fully automatic tracking total station 3; in the present invention, the two GPS4 and the fully automatic tracking total station are on the same plane, so the elevation difference z is 0.

[0025] According to the three-dimensional coordinates of the fully automatic tracking total station 3 , combined with the horizontal angle of the steel cylinder measured by the fully automatic tracking total station 3 , vertical angle , slope distance S , calculate the center point of the cross 8 inside the steel cylinder 7 P The three-dimensional coordinates of : ; Where, The center point of the steel cylinder 7 P The three-dimensional coordinates of To automatically track the three-dimensional coordinates of the total station 3, The center point of the steel cylinder 7 P The horizontal angle, The center point of the steel cylinder 7 P The vertical angle, S The center point of the steel cylinder 7 P slant distance.

[0026] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for locating the position of an offshore structure based on an unmanned aerial vehicle (UAV)-borne monitoring system, characterized in that: The UAV cargo monitoring system includes a rigid platform, a UAV cluster, a fully automatic tracking total station, a GPS, a dual-axis tilt sensor, and an ultrasonic ranging sensor; wherein the rigid platform is an equilateral triangle, the UAV cluster is used to lift the rigid platform, the number of UAVs in the UAV cluster is consistent with the number of corner points of the rigid platform, the fully automatic tracking total station is fixedly set at the midpoint of one side of the rigid platform, a GPS is set at the midpoint of the other two sides of the rigid platform, the dual-axis tilt sensor is fixedly set at the center position of the rigid platform, and the ultrasonic ranging sensor is fixedly set at each corner point of the rigid platform; The following steps are involved: Step 1: After the drone cluster hoisted the rigid platform to the oblique upper part of the offshore structure, the drone hovering mode was activated; Step 2: Use the data from the ultrasonic ranging sensor to adjust the flight altitude of the drone cluster, and then adjust the inclination of the rigid platform. Use the dual-axis inclination sensor to measure the inclination data and further calibrate the horizontality of the rigid platform. Step 3: Use the fully automatic tracking total station to measure the center point of the reflector of the offshore structure P Horizontal angle , vertical angle , slope distance S And upload it to the host computer, which calculates the three-dimensional coordinates of the fully automatic tracking total station based on the GPS coordinate data, and then calculates the center point of the offshore structure P The three-dimensional coordinates of .

2. The method for locating the position of an offshore structure based on an unmanned aerial vehicle (UAV)-borne monitoring system according to claim 1, characterized in that: The rigid platform is made of carbon fiber material.

3. The method for locating the position of an offshore structure based on an unmanned aerial vehicle (UAV)-borne monitoring system according to claim 1, characterized in that: The GPS and the fully automatic tracking total station are on the same plane.

4. The method for locating the position of an offshore structure based on an unmanned aerial vehicle (UAV)-borne monitoring system according to claim 1, characterized in that: A backsight reflector is attached to the base of one of the GPS units to serve as the backsight point for the fully automatic tracking total station.

5. The method for locating the position of an offshore structure based on an unmanned aerial vehicle (UAV)-borne monitoring system according to claim 1, characterized in that: In step 1, the offshore structure is a steel cylinder, a cross is placed 10 to 15 cm downward from the inner opening of the steel cylinder, and a reflective sheet is attached to the center of the cross.

6. The method for locating the position of an offshore structure based on an unmanned aerial vehicle (UAV)-borne monitoring system according to claim 1, characterized in that: In step 3, the center point of the offshore structure P The three-dimensional coordinates of The calculation formula is: ； Where, To automatically track the three-dimensional coordinates of the total station, The center point of the offshore structure P The horizontal angle, The center point of the offshore structure P The vertical angle, S The center point of the offshore structure P slant distance.

7. The method for locating the position of an offshore structure based on an unmanned aerial vehicle (UAV)-borne monitoring system according to claim 6, characterized in that: The three-dimensional coordinates of the fully automatic tracking total station The calculation formula is: ； Where, is the three-dimensional coordinate of one of the GPS, is the three-dimensional coordinate of another GPS, z It is the elevation difference between GPS and fully automatic tracking total station; is the vector between the two GPSs, The calculation formula is: .

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