Method for locating marine structures based on unmanned aerial vehicle (UAV) cargo monitoring systems

Abstract

This invention discloses a method for locating offshore structures using an unmanned aerial vehicle (UAV)-borne monitoring system. The UAV-borne monitoring system employs a rigid platform carried by a swarm of UAVs. A fully automatic tracking total station, GPS, a dual-axis tilt sensor, and an ultrasonic ranging sensor are installed on the rigid platform. After the UAV swarm carries the rigid platform and flies to an angled position above the offshore structure, it hovers. Data from the ultrasonic ranging sensor is used to adjust the flight altitude of the UAV swarm. The tilt angle data measured by the dual-axis tilt sensor is used to further calibrate the levelness of the rigid platform. The fully automatic tracking total station measures the horizontal angle, vertical angle, and slant distance of the offshore structure and uploads this data to a host computer. The host computer calculates the three-dimensional coordinates of the fully automatic tracking total station based on the GPS coordinate data, and then calculates the three-dimensional coordinates of the center point of the offshore structure. This invention enables the location of offshore structures, avoids monitoring blind spots, and reduces personnel risks.

Description

Technical Field

[0001] This invention relates to the field of unmanned aerial vehicle (UAV) technology, and in particular to a method for locating the position of offshore structures based on an UAV-borne cargo monitoring system. Background Technology

[0002] Offshore steel cylinders are a type of large-scale marine steel structure that is highly efficient, reliable, and multifunctional, and they have shown great advantages, especially in the rapid construction of offshore dikes and artificial islands.

[0003] Offshore steel cylinders are typically several meters above sea level. Traditionally, positioning is achieved using a nearby positioning vessel. However, during offshore engineering monitoring, a monitoring vessel is usually brought close to the object being measured, and sensors are manually deployed on the object for monitoring, which poses certain safety risks. Alternatively, the monitoring device can be placed on the monitoring vessel, but sometimes the object being measured is much higher than the vessel, creating blind spots in the monitoring. Summary of the Invention

[0004] The purpose of this invention is to address the technical deficiencies in the existing technology by providing a method for locating the position of marine structures based on an unmanned aerial vehicle (UAV) cargo monitoring system.

[0005] The technical solution adopted to achieve the purpose of this invention is:

[0006] This invention designs a method for locating the position of offshore structures based on an unmanned aerial vehicle (UAV) cargo monitoring system. The UAV cargo monitoring system includes a rigid platform, a UAV swarm, 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 swarm is used to hoist the rigid platform, and the number of UAVs in the swarm is the same as the number of corner points of the rigid platform. The fully automatic tracking total station is fixedly located at the midpoint of one side of the rigid platform, and a GPS is installed at the midpoint of each of the other two sides of the rigid platform. The dual-axis tilt sensor is fixedly located at the center of the rigid platform, and the ultrasonic ranging sensor is fixedly located at each corner point of the rigid platform.

[0007] Includes the following steps:

[0008] Step 1: After the drone swarm carries the rigid platform and flies to the oblique airspace above the offshore structure, the drone hovering mode is activated.

[0009] Step 2: Use data from ultrasonic ranging sensors to adjust the flight altitude of the drone swarm, thereby adjusting the tilt of the rigid platform. Use dual-axis tilt sensors to measure the tilt angle data and further calibrate the levelness of the rigid platform.

[0010] Step 3: Use a fully automatic tracking total station to measure the center point of the reflector of the marine structure. P horizontal angle vertical angle Slope distance S The data is then uploaded to a 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.

[0011] In the above technical solution, the rigid platform is made of carbon fiber material.

[0012] In the above technical solution, the GPS and the fully automatic tracking total station are on the same plane.

[0013] 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 for the fully automatic tracking total station.

[0014] In the above technical solution, in step 1, the offshore structure is a steel cylinder, and a cross is placed 10-15cm below the opening of the steel cylinder, with a reflective sheet attached to the center of the cross.

[0015] In the above technical solution, in step 3, the center point of the offshore structure P 3D coordinates The calculation formula is:

[0016] ;

[0017] In the formula, To automatically track the three-dimensional coordinates of the total station, Center point of offshore structures P Horizontal angle, Center point of offshore structures P The vertical angle, S Center point of offshore structures P The slope distance.

[0018] In the above technical solution, the three-dimensional coordinates of the fully automatic tracking total station are... The calculation formula is:

[0019] ;

[0020] In the formula, The three-dimensional coordinates of one of the GPS devices. For the three-dimensional coordinates of another GPS device, z For the elevation difference between GPS and fully automatic tracking total station; The vector between the two GPS devices. The calculation formula is: .

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] 1. This invention utilizes the characteristics of high-altitude operation of UAVs to achieve the positioning of offshore structures (such as offshore steel cylinders) by deploying a fully automatic tracking total station, GPS positioning sensor, ultrasonic ranging sensor, and dual-axis tilt sensor on a rigid platform, thereby avoiding monitoring blind spots, reducing personnel risks, and is especially suitable for rapid measurement in complex sea areas.

[0023] 2. This invention uses a carbon fiber composite rigid platform, which is lightweight and highly rigid, making it suitable for drone mounting scenarios;

[0024] 3. The method for locating the position of marine structures based on the UAV-borne object monitoring system of the present invention is not affected by the height of the object being measured. As long as the rigid platform carried by the UAV is located diagonally above the object being measured, and a prism or reflector is stably placed on the object being measured at a position that is conducive to measurement, the accurate three-dimensional coordinates of the object being measured can be obtained through distance conversion. Attached Figure Description

[0025] Figure 1 The diagram shown is a structural schematic of the unmanned aerial vehicle (UAV) cargo monitoring system of the present invention.

[0026] Figure 2 The diagram shows the distribution of GPS and fully automatic tracking total station on the rigid platform of the UAV cargo monitoring system of the present invention.

[0027] In the diagram: 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-reflector. Detailed Implementation

[0028] 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 merely illustrative of the invention and are not intended to limit the invention.

[0029] This invention presents a method for locating offshore structures, which is implemented based on an unmanned aerial vehicle (UAV)-borne monitoring system, referring to... Figure 1The unmanned aerial vehicle (UAV) cargo monitoring system includes a rigid platform 1, a UAV swarm, a fully automatic tracking total station 3, a GPS 4, a dual-axis tilt sensor 5, and an ultrasonic ranging sensor 6. The UAV swarm is used to suspend the rigid platform 1. The number of UAVs 2 in the UAV swarm is the same as 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 each of the other two sides of the rigid platform 1. A backsight reflector is attached to the base of one of the GPS 4s to serve as the backsight point of the fully automatic tracking total station 3. The dual-axis tilt sensor 5 is fixedly set at the center of the rigid platform 1. The ultrasonic ranging sensor 6 is fixedly set at each corner point of the rigid platform 1.

[0030] Furthermore, the rigid platform 1 is made of carbon fiber composite material, which is lightweight and highly rigid, making it suitable for drone-borne applications; the GPS4 uses RTK differential technology, which makes the GPS4 coordinates more accurate and provides a reliable reference for the fully automatic tracking total station 3 measurement.

[0031] The method for locating offshore structures based on the above-mentioned UAV-borne cargo monitoring system is as follows:

[0032] First, three drones 2 are used to suspend a rigid triangular platform 1. After the drone cluster flies to the upper part of the steel cylinder 7, the drone hovering mode is activated.

[0033] Secondly, the flight altitude of each UAV 2 is adjusted using data from ultrasonic ranging sensors 6 located at the three corners of the rigid platform 1, thereby adjusting the tilt of the rigid platform 1 to keep it level. Then, the tilt angle data of the rigid platform 1 is measured using a dual-axis tilt sensor 5 fixed at the center of the rigid platform 1, further calibrating the levelness of the rigid platform 1. The GPS data and the data from the fully automatic tracking total station 3 are synchronized via a hardware synchronization clock or software settings. Before measuring the data of the steel cylinder 7, the GPS 4 with a backsight reflector on its base confirms the backsight azimuth of the fully automatic tracking total station 3, completing the orientation and providing a directional reference for subsequent measurements.

[0034] Finally, the center point of the reflector 9 on the cross 8 inside the steel cylinder 7 was measured using a fully automatic tracking total station 3. P horizontal angle vertical angle Slope distance SSimultaneously, coordinate data from two GPS 4 devices are read. Since the coordinate data of the fully automatic tracking total station 3 changes in real time as the drone 2 flies, this embodiment uses the coordinate data measured by the GPS 4 devices and the horizontal angle of the steel cylinder 7 measured by the fully automatic tracking total station 3. vertical angle Slope distance S Simultaneously, the data is uploaded to the host computer, which then calculates the coordinates of the fully automatic tracking total station 3 based on the coordinate data from the two GPS 4 devices, and further calculates the center point of the cross 8 inside the steel cylinder 7. P The three-dimensional coordinates.

[0035] Reference Figure 2 Let the rigid platform 1 of the equilateral triangle be △ABC, and the fully automatic tracking total station 3 be located at the midpoint of side AB. Define two GPS devices as GPS. i and GPS j The GPS i Located at the midpoint of side BC GPS j Located at the midpoint of edge CA The triangle is in a counter-clockwise direction. M c In vector Left side.

[0036] The GPS i and GPS j The midpoint of the edge M a 、M b vector The calculation formula is:

[0037] ;

[0038] In the formula, and GPS respectively i and GPS j The three-dimensional coordinates.

[0039] The three-dimensional coordinates of the fully automatic tracking total station 3 The calculation formula is:

[0040] ;

[0041] In the formula, For GPS i and GPS j The midpoint of the edge M a 、M b The vector, For GPS i The three-dimensional coordinates For GPS j The three-dimensional coordinates. z The elevation difference is between GPS 4 and the fully automatic tracking total station 3; in this invention, the two GPS 4 units and the fully automatic tracking total station are on the same plane, therefore the elevation difference is... z It is 0.

[0042] Based on the three-dimensional coordinates of the fully automatic tracking total station 3 The horizontal angle of the steel cylinder was measured by the fully automatic tracking total station 3. vertical angle Slope distance S The center point of the cross 8 inside the steel cylinder 7 was calculated. P 3D coordinates :

[0043] ;

[0044] In the formula, Center point of steel cylinder 7 P The three-dimensional coordinates To automatically track the three-dimensional coordinates of the total station 3, Center point of steel cylinder 7 P Horizontal angle, Center point of steel cylinder 7 P The vertical angle, S Center point of steel cylinder 7 P The slope distance.

[0045] The above description is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for locating the position of offshore structures based on an unmanned aerial vehicle (UAV)-borne cargo monitoring system, characterized in that, The UAV-borne cargo monitoring system includes a rigid platform, a UAV swarm, 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 swarm is used to suspend the rigid platform, and the number of UAVs in the swarm is the same as the number of corner points of the rigid platform. The fully automatic tracking total station is fixedly located at the midpoint of one side of the rigid platform, and a GPS is installed at the midpoint of each of the other two sides. The dual-axis tilt sensor is fixedly located at the center of the rigid platform, and the ultrasonic ranging sensor is fixedly located at each corner point of the rigid platform. Includes the following steps: Step 1: After the drone swarm carries the rigid platform and flies to the oblique airspace above the offshore structure, the drone hovering mode is activated. Step 2: Use data from ultrasonic ranging sensors to adjust the flight altitude of the drone swarm, thereby adjusting the tilt of the rigid platform. Use dual-axis tilt sensors to measure the tilt angle data and further calibrate the levelness of the rigid platform. Step 3: Use a fully automatic tracking total station to measure the center point of the reflector of the marine structure. P horizontal angle vertical angle Slope distance S The data is then uploaded to a 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.

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

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

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

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

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