Metal buried object detection method based on unmanned aerial vehicle and magnetic detection unmanned aerial vehicle

Abstract

The invention discloses a metal buried object detection method based on an unmanned aerial vehicle and a magnetic detection unmanned aerial vehicle, in a static parking state of the unmanned aerial vehicle, an open static magnetic field interference area close to a to-be-detected metal buried object task area is selected for calibration, and a magnetic detection sensor is started to record magnetic induction intensity data of a current environment; starting the unmanned aerial vehicle, recording flight state data of the unmanned aerial vehicle in real time, controlling the unmanned aerial vehicle to perform magnetic compensation action flight according to a preset track, acquiring magnetic induction intensity data in real time until magnetic compensation is completed, and finally performing simulated flight over a metal buried object task area according to a set task route. And eliminating interference data in a task route by using a magnetic compensation parameter to obtain corrected magnetic induction intensity data, positioning whether a task site contains magnetic substances or not according to difference change of probe data on two sides of the unmanned aerial vehicle, and superposing corresponding position data of the unmanned aerial vehicle to obtain the position of the metal buried object. Therefore, the metal detection precision of the unmanned aerial vehicle is improved.

Description

Technical Field

[0001] The present invention relates to the field of drone detection technology, and in particular to a drone-based metal buried object detection method and a magnetic detection drone. Background Art

[0002] Accurately detecting and locating buried metal objects is crucial in fields such as geological exploration, archaeological excavation, and military reconnaissance. Traditional ground-based detection methods often struggle to efficiently and accurately complete tasks due to limitations in terrain and environmental conditions. However, drones, as a new technological tool, offer a new solution for buried metal detection with their high maneuverability and flexibility. UAV aeromagnetic systems, an advanced aerial detection method, utilize drone-mounted magnetic sensors to measure real-time changes in the geomagnetic field during flight, enabling non-contact detection of buried metal objects. However, the inherent maneuverability of drones in flight generates magnetic field interference, introducing maneuvering magnetic noise into the target data, seriously impacting the accurate identification and determination of buried metal objects. Particularly in complex and changing environments, this interference can significantly bias detection results or even lead to detection failure. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the present invention provides a method for detecting buried metal objects based on a drone, comprising the following steps:

[0004] S1: When the UAV is in a static parking state, select an open static magnetic field interference area near the task area of ​​metal buried objects to be detected for calibration, and start the magnetic detection sensors on both sides of the UAV to record the magnetic induction intensity data of the current environment;

[0005] S2, starting the UAV and recording the UAV's flight status data in real time, the flight status data including position information, speed information, and current information of each motor; controlling the UAV to perform magnetic compensation flight along a preset trajectory, wherein the magnetic detection sensor collects magnetic induction intensity data in real time until magnetic compensation is completed;

[0006] S3: Perform a simulated ground flight over the metal buried object mission area according to the set mission route and record the magnetic induction intensity data in real time. Use magnetic compensation parameters to eliminate the environmental interference data in the mission route and the interference data during the UAV maneuvering process to obtain the corrected magnetic induction intensity data of the mission site. Based on the difference in the probe data on both sides of the UAV, locate whether the mission site contains magnetic materials, and obtain the location of the metal buried object by superimposing the corresponding position data of the UAV.

[0007] Preferably, step S2 specifically includes: after the UAV is started, the UAV is controlled to climb to the set magnetic compensation route starting height, enter the magnetic compensation flight mode, and collect and record the magnetic sensor measurement data in real time until the magnetic compensation flight mode ends; the magnetic compensation flight mode is configured to randomly select a starting route direction in the quadrilateral of due east, south, west, and north, perform compensation maneuvers and collect magnetic declination variables, and after the compensation maneuver in each route direction is completed, turn clockwise or counterclockwise to proceed to the next route direction, wherein the compensation maneuver is set to sequentially perform a set number of positive and negative angles of rolling with the X-axis as the center axis, a set number of positive and negative angles of pitching with the Y-axis as the center axis, and a set number of positive and negative angles of yaw with the Z-axis as the center axis. The amplitude of the movement is based on the maximum deflection angle that can be caused by normal maneuvering of the aircraft. A deviation angle close to the actual maximum flight angle can be measured to be closer to the actual flight self-noise, thereby effectively compensating.

[0008] Preferably, step S3 further includes: locating whether the mission site contains magnetic materials according to the difference change of the probe data on both sides of the UAV, obtaining the rough position of the buried metal object after superimposing the corresponding position data of the UAV, generating a second mission area covering the rough position according to the rough position, wherein the second mission area is smaller than the buried metal object mission area; generating a precise detection route and a corresponding second flight parameter group according to the second mission area, wherein the speed in the second flight parameter group is lower than the speed in the flight parameters of the previous buried metal object mission area, and / or the height in the second flight parameter group is lower than the height in the flight parameters of the previous buried metal object mission area; after being loaded into the UAV, performing a ground-simulating flight over the second mission area, and recording the second magnetic induction intensity data in real time, and obtaining the precise position of the buried metal object after superimposing the corresponding position data of the UAV according to the difference change of the probe data on both sides of the UAV.

[0009] Preferably, step S3 further includes: drawing a magnetic anomaly field contour map and a magnetic anomaly field three-dimensional map of the detection area based on the corrected magnetic induction intensity data of the mission site obtained, and evaluating the location and burial form of the buried metal object based on the different magnetic characteristics presented in the magnetic anomaly field three-dimensional map.

[0010] The present invention also discloses a magnetic detection drone, comprising a rotor drone body, a controller mounted on the body, a crossbar bracket detachably connected to the bottom of the body, two magnetic detection sensors respectively mounted at both ends of the crossbar bracket, and a terminal station capable of communicating with the controller, wherein the controller is configured to: when the drone is in a static parking state, select an open static magnetic field interference area adjacent to a task area of ​​buried metal objects to be detected for calibration, start the magnetic detection sensors mounted on both sides of the drone to record magnetic induction intensity data of the current environment; start the drone, and record the flight status data of the drone in real time, wherein the flight status data includes position information, speed information, and the power of each motor. The method comprises the following steps: controlling the UAV to perform magnetic compensation flight according to a preset trajectory, wherein the magnetic detection sensor collects magnetic induction intensity data in real time until magnetic compensation is completed; performing a ground-simulating flight over a metal buried object mission area according to a set mission route, and recording magnetic induction intensity data in real time; the terminal station is configured to: eliminate environmental interference data in the magnetic induction intensity data collected during the mission route and interference data during the UAV maneuvering process using magnetic compensation parameters, thereby obtaining corrected magnetic induction intensity data for the mission site; locating whether the mission site contains magnetic materials based on the difference change in the probe data on both sides of the UAV, and obtaining the position of the metal buried object by superimposing the corresponding position data of the UAV.

[0011] Preferably, the controller is configured to: after the UAV is started, control the UAV to climb to the set magnetic compensation route starting height, enter the magnetic compensation flight mode, and collect and record the magnetic sensor measurement data in real time until the magnetic compensation flight mode ends; the magnetic compensation flight mode is configured to randomly select a starting route direction in the quadrilateral of east, south, west and north, perform compensation maneuvers and collect magnetic declination variables, and after the compensation maneuver in each route direction is completed, turn clockwise or counterclockwise to the next route direction, wherein the compensation maneuver is set to perform a set number of positive and negative angles of rolling with the X-axis as the center axis, a set number of positive and negative angles of pitching with the Y-axis as the center axis, and a set number of positive and negative angles of yaw with the Z-axis as the center axis. The amplitude of the movement is based on the maximum declination angle that can be caused by normal maneuvering of the aircraft. A deviation angle close to the actual maximum flight angle can be measured to be closer to the actual flight self-noise, thereby effectively compensating.

[0012] Preferably, the terminal station is further configured to locate whether the mission site contains magnetic materials based on the difference change of the probe data on both sides of the UAV, obtain the rough position of the buried metal object after superimposing the corresponding position data of the UAV, generate a second mission area covering the rough position based on the rough position, and the second mission area is smaller than the buried metal object mission area; generate a precise detection route and a corresponding second flight parameter group based on the second mission area, wherein the speed in the second flight parameter group is lower than the speed in the flight parameters of the previous buried metal object mission area, and / or the height in the second flight parameter group is lower than the height in the flight parameters of the previous buried metal object mission area; after the controller loads the precise detection route and the second flight parameter group data sent by the terminal station, it performs a ground-simulating flight over the second mission area and records the second magnetic induction intensity data in real time; the terminal station obtains the precise position of the buried metal object after superimposing the corresponding position data of the UAV based on the difference change of the probe data on both sides in the received second magnetic induction intensity data.

[0013] Preferably, the terminal station is also configured to draw a magnetic anomaly field contour map and a three-dimensional magnetic anomaly field map of the detection area based on the corrected magnetic induction intensity data of the mission site obtained, and evaluate the location and burial form of the buried metal objects based on the different magnetic characteristics presented in the three-dimensional magnetic anomaly field map.

[0014] Preferably, the cross bar bracket includes a first rod body, a second rod body and a third rod body, the first rod body is fixedly connected to the rotor UAV body bracket, the two ends of the first rod body are respectively foldably connected to one end of the second rod body and one end of the third rod body, the other end of the second rod body is detachably connected to a magnetic detection sensor through a magnetic detection mounting base, and the other end of the third rod body is detachably connected to another magnetic detection sensor through a magnetic detection mounting base.

[0015] Preferably, the magnetic probe mounting seat includes a connecting part connected to the end of the rod body, multiple groups of clamping arms connected to the side of the connecting part away from the rod body, and a base located below the clamping arm. The upper part of the connecting part is provided with a storage limit structure protruding upward, and the storage limit structure includes a top plate, a side blocking plate and a front blocking plate. The upper wall of the connecting part is surrounded by the top plate, the side blocking plate and the front blocking plate to form a storage cavity for accommodating the magnetic probe sensor connector. The upper edge of the front blocking plate is provided with a wire groove recessed toward the side blocking plate.

[0016] The present invention discloses a buried metal object detection method and a magnetic detection drone based on a drone. When the drone is in a static state, an open static magnetic field interference area adjacent to a task area of ​​a buried metal object to be detected is selected for calibration, and the magnetic induction intensity data of the current environment is recorded. The drone is then started to perform magnetic compensation flight, flight status data is recorded, and magnetic induction intensity data is collected in real time to eliminate the drone's own magnetic field interference. Finally, a ground-simulating flight is performed according to a set task route, and magnetic compensation parameters are used to eliminate interference data. The position of the buried metal object is located according to the difference change in probe data. The magnetic noise interference generated during the drone's maneuvering process is effectively eliminated through magnetic compensation flight, thereby improving the accuracy of magnetic measurement data, thereby being able to more accurately locate the position of the buried metal object, and providing an efficient and accurate solution for metal detection tasks.

[0017] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0019] Figure 1 The figure is a schematic diagram of the steps of a method for detecting buried metal objects based on a drone according to an embodiment of the present invention.

[0020] Figure 2 A schematic diagram of the magnetic compensation action of a drone disclosed in one embodiment of the present invention.

[0021] Figure 3 A schematic diagram of a coordinate system for compensation calculation disclosed in an embodiment of the present invention.

[0022] Figure 4 This is a schematic diagram of the specific steps of step S3 disclosed in one embodiment of the present invention.

[0023] Figure 5 This is a schematic structural diagram of a magnetic detection drone disclosed in another embodiment of the present invention.

[0024] Figure 6 This is a schematic structural diagram of a crossbar bracket in a folded state according to another embodiment of the present invention.

[0025] Figure 7 This is a schematic structural diagram of a magnetic probe mounting base disclosed in another embodiment of the present invention. DETAILED DESCRIPTION

[0026] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] In the present invention, unless otherwise expressly defined or limited, technical or scientific terms used herein shall have the ordinary meanings understood by persons of ordinary skill in the art to which the present invention pertains. The terms "first," "second," and similar terms used in the present patent application specification and claims do not denote any order, quantity, or importance, but are merely used to distinguish different components. Similarly, terms such as "a" or "an" do not denote a limitation of quantity, but rather denote the presence of at least one.

[0028] This embodiment discloses a method for detecting buried metal objects based on a drone. Figure 1 As shown, the following steps are included:

[0029] Step S1: When the UAV is in a static parking state, select an open static magnetic field interference area near the metal buried object mission area to be detected for calibration, and start the magnetic detection sensors on both sides of the UAV to record the magnetic induction intensity data of the current environment.

[0030] This embodiment eliminates the maneuvering magnetic noise interference generated during the flight of the drone based on the magnetic compensation principle of the TL model. The drone used is pre-equipped with magnetic detection sensors on both sides, which can read and record the drone's position, speed, total current, and current data of each motor in real time through the data interface. Specifically, the method includes two parts: interference data collection and magnetic compensation parameter calculation before the formal flight, and interference data elimination and metal detection object positioning after the formal flight. Among them, the interference data includes environmental interference data and maneuvering interference data. The drone collects environmental interference data of the task area for the metal buried objects to be detected and magnetic interference data caused by various maneuvers during the drone test flight before the formal flight, and uses the TL model to analyze these data in detail, thereby solving the magnetic compensation parameters of the drone. According to the aeromagnetic data collected by the drone during the formal flight, effective magnetic interference elimination processing can be performed to accurately locate the metal detection object to be measured in the task area.

[0031] Specifically, due to the existence of the Earth's natural geomagnetic field, the strength, direction, and other characteristics of the geomagnetic field vary from location to location, which itself will act as a background interference factor affecting the subsequent measurement of magnetic field changes caused by buried metal objects. At the same time, since there may be some fixed, magnetic objects in and around the mission area, the relatively stable magnetic fields generated by them will also interfere with the magnetic detection sensors on the drone to accurately measure the geomagnetic field changes caused by the target buried metal objects. Therefore, before the drone test flight, it is necessary to measure this type of environmental magnetic field interference data. By activating the magnetic detection equipment of the drone in a static state in the area to be detected, the magnetic induction intensity data of the current environment, including the magnetic induction intensity information of the current calibration location, is obtained. These data reflect the strength and direction of the geomagnetic field at the current location and other possible static magnetic field interferences. In the subsequent process, they can be used to effectively eliminate or reduce the interference of the environmental magnetic field on the measurement results, thereby improving the accuracy and reliability of magnetic detection.

[0032] Step S2: Start the UAV and record the flight status data of the UAV in real time, wherein the flight status data includes position information, speed information, and current information of each motor; control the UAV to perform magnetic compensation action according to a preset trajectory, wherein the magnetic detection sensor collects magnetic induction intensity data in real time until the magnetic compensation is completed.

[0033] Specifically, during the flight of a drone, its own maneuverability will cause certain magnetic field interference. For example, when performing maneuvers such as acceleration, deceleration, turning, ascent, descent, etc., the operating state of the motors, circuits and other components inside the drone changes, and physical quantities such as current also change accordingly, thereby generating magnetic field changes and forming maneuver interference data. These magnetic variables caused by maneuvering will be superimposed on the geomagnetic field change signal caused by the target metal buried object to be detected, generating maneuver magnetic noise interference, which seriously affects the accurate identification and determination of the metal buried object. Therefore, this embodiment collects these maneuver interference data by performing magnetic compensation maneuvers according to a preset trajectory during the drone test flight phase, and analyzes and processes them together with environmental interference data in combination with methods such as the TL model, thereby calculating magnetic compensation parameters, thereby effectively eliminating various types of interference generated during the drone flight process and achieving precise positioning of the metal detector to be measured.

[0034] Specifically, step S2 includes the following contents.

[0035] Step S21: After the UAV is started, the UAV is controlled to climb to the set starting altitude of the magnetic compensation route, enter the magnetic compensation flight mode, and collect and record the magnetic sensor measurement data in real time until the magnetic compensation flight mode ends.

[0036] In this embodiment, the starting height of the magnetic compensation route is configured to any value between 80-100m to maintain the high-altitude flight state of the UAV test process, reduce the interference of the environmental magnetic field, obtain the pure magnetic anomaly variable value caused by the UAV maneuver, and obtain the compensation coefficient in the subsequent calculation to improve the measurement accuracy of the magnetic sensor. Figure 2 As shown, the magnetic compensation flight mode is configured to randomly select a starting route direction in the quadrilateral of east, south, west and north, perform compensation maneuvers and collect magnetic declination variables, and after the compensation maneuver in each route direction is completed, turn clockwise or counterclockwise to proceed to the next route direction, wherein the compensation maneuver is set to sequentially perform a set number of positive and negative angles of roll with the X-axis as the center axis, a set number of positive and negative angles of pitch with the Y-axis as the center axis, and a set number of positive and negative angles of yaw with the Z-axis as the center axis. The amplitude of the movement is based on the maximum declination angle that can be caused by normal maneuvering of the aircraft. A maximum angle close to the actual flight can measure self-noise closer to the actual flight, thereby effectively compensating. By randomly selecting the starting route direction in the quadrilateral of east, south, west and north, performing multiple posture simulations around different coordinate axes, and setting the movement amplitude according to the maximum declination angle of the aircraft's normal maneuver, implementing compensatory maneuvers in various directions and collecting magnetic declination variables, it is possible to fit the actual flight conditions and realize the collection of multi-directional and multi-angle data on magnetic field changes during the UAV maneuvering process, thereby improving the accuracy of interference analysis, and optimizing the metal buried object detection process as a whole, reducing the impact of interference, improving the detection success rate and positioning accuracy, and ensuring the reliable completion of the detection mission.

[0037] Step S22, based on the magnetic induction intensity data of the current environment collected when the drone is in a static parking state and the magnetic induction intensity data collected when the drone is started and performing magnetic compensation flight actions, the magnetic compensation model is used to calculate the magnetic compensation parameters of the drone in the mission area.

[0038] In this embodiment, the magnetic interference of the UAV platform is decomposed into three parts: a constant magnetic field, an induced magnetic field, and an eddy current magnetic field, and the magnetic interference coefficient is solved by establishing an overdetermined linear equation group. The constant magnetic field, also known as the residual magnetic field, is a magnetic field with a stable intensity over a certain period of time formed by the hard magnetic material of the aircraft under the magnetization action of the external magnetic field; the induced magnetic field is the magnetic field generated by the soft magnetic material of the aircraft being magnetized by the earth's magnetic field during the movement of the aircraft; and the eddy current magnetic field is the magnetic field generated by the loop conductor of the aeromagnetic system cutting the external magnetic field during the aircraft maneuvering. The corresponding coordinate system is as follows: Figure 3 As shown in the figure, X, Y, and Z are spatial coordinate axes, Y represents the longitudinal axis of the aircraft, X represents the transverse axis of the aircraft, and the Z axis is perpendicular to the XOY plane; x, y, and z are the angles between the geomagnetic field and the coordinate axes, respectively; B is the measurement field of the magnetometer; Bg is the geomagnetic field; and Bd is the interfering magnetic field.

[0039] Specifically, the interfering magnetic field B d Through the constant interference field B p 、Induction interference field B i , eddy current interference field B e express:

[0040] B d =B p +B i +B e ;

[0041] in,

[0042]

[0043]

[0044] cosx, cosy, cosz are the direction cosines of the angles x, y, and z, respectively; cosx', cosy', cosz' are the time derivatives of the direction cosines of the angles x, y, and z, respectively; c1, c2, and c3 are the constant interference field compensation coefficients, and b ij (i, j = 1, 2, 3), c4, c5, c6, c7, c8 represent the compensation coefficients of the induction interference field respectively; c ij (ij=11,22,…,33) is the compensation coefficient of the eddy current interference field.

[0045] After calculation, we can get:

[0046] B d =AC;

[0047]

[0048] C=[c1 c2…c 15 c 16 ] T .

[0049] Where C is the compensation coefficient matrix, which includes 16 items; A is the matrix composed of direction cosines and their derivatives, with a total of 16×N items.

[0050] During the test flight, the 16 coefficients of the A matrix and the B matrix were obtained through the test flight. d Magnetic interference value data, and then use formula B d =AC to solve the compensation coefficient matrix C. Finally, the estimated compensation coefficient matrix C and direction cosine information are substituted into the formula in the aeromagnetic measurement to solve the total magnetic interference field in real time, thereby realizing aeromagnetic data compensation.

[0051] Furthermore, when there are multiple terrains within the mission area, the mission area needs to be divided into regions to ensure the accuracy of drone detection, including the following.

[0052] In step S101, the mission area is pre-divided into multiple sub-task areas, the UAV is controlled to fly to the center of each sub-task area and stop flying. When the UAV is in a static parking state, the magnetic detection sensors mounted on both sides of the UAV are started to record the magnetic induction intensity data of each sub-task interval.

[0053] Specifically, by utilizing geographic information systems or remote sensing technology, a preliminary analysis of the mission area is conducted, and it is intelligently pre-divided into multiple sub-task areas based on terrain, landform, geology and other characteristics. The size and shape of the sub-task areas are reasonably set according to the flight capabilities of the UAV and the detection range of the magnetic detection sensor.

[0054] Step S102 compares the magnetic flux density data of each subtask area. If the magnetic flux density data of two adjacent subtask areas is lower than the first static magnetic flux density difference, the two adjacent subtask areas are merged. If the magnetic flux density of two adjacent subtask areas is higher than the second static magnetic flux density difference, the two subtask areas are evenly divided, and step S101 is repeated until the magnetic flux density data of each subtask area is higher than the first static magnetic flux density difference and lower than the second static magnetic flux density difference. Specifically, the direction of division of the subtask area is configured to pass through the center position of the subtask area and be perpendicular to the line connecting the centers of the two adjacent subtask areas whose magnetic flux density is higher than the second static magnetic flux density difference.

[0055] Step S103: Start the drones in each subtask area and record the flight status data of the drones in real time; control the drones to perform magnetic compensation actions according to a preset trajectory, wherein the magnetic detection sensor collects magnetic induction intensity data in real time until the magnetic compensation is completed.

[0056] Specifically, through the above steps, the mission area is pre-divided into multiple sub-task areas, and the drone is used to collect accurate magnetic induction intensity data of each sub-task area in a static state, ensuring that the collected magnetic induction intensity data effectively reflects the magnetic interference conditions in different areas, avoiding the problem of magnetic compensation parameters not being consistent with the actual situation during unified calculation due to changes in factors such as terrain, and improving the accuracy of drone detection.

[0057] In this embodiment, due to the relatively small fluctuations in the drone's flight attitude, the coefficient matrix in the compensation model often suffers from severe multicollinearity, a problem known as ill-conditioned solution. To address this issue, this embodiment employs methods such as improved ridge regression estimation and truncated singular value estimation to mitigate the effects of multicollinearity. Furthermore, the drone's body is constructed from synthetic materials such as carbon fiber and glass fiber to mitigate the impact of interference fields.

[0058] In step S3, the drone performs a simulated flight over the buried metal object mission area according to the set mission route, and records the magnetic induction intensity data in real time. The magnetic compensation parameters are used to eliminate the environmental interference data in the mission route and the interference data during the UAV maneuvering process to obtain the corrected magnetic induction intensity data of the mission site. Based on the difference in the probe data on both sides of the UAV, the presence of magnetic material in the mission site is determined, and the location of the buried metal object is obtained by superimposing the corresponding position data of the UAV.

[0059] Specifically, when a buried metal object is located underground, it will be induced magnetized by the Earth's magnetic field, creating an additional magnetic field around it. This can cause abnormal conditions such as an increase or decrease in the surrounding magnetic field, which is reflected in a difference in magnetic induction intensity. When a drone flies over a buried metal object, the additional magnetic field causes the drone's magnetic sensors to measure abnormal magnetic induction intensity values. By comparing the difference in data collected by the magnetic sensors on both sides of the drone, it can be determined whether a buried metal object is beneath the drone. During this process, the drone flies along a pre-set mission route, maintaining a relatively constant altitude above the ground. The real-time recorded magnetic induction intensity data is input into a data processing system. Magnetic compensation parameters are applied to eliminate interference data from environmental interference during flight and interference generated by the drone's own maneuvers in real time, ensuring that the acquired magnetic induction intensity data accurately reflects the actual magnetic field conditions at the mission site. The drone then locates the magnetic material by overlaying the drone's data position, accurately determining the location of the metal object.

[0060] In this embodiment, if Figure 4 As shown, the step S3 also includes the following contents.

[0061] In step S31, the mission site is located to determine whether there is magnetic material based on the difference in the probe data on both sides of the drone. The rough position of the buried metal object is obtained by superimposing the corresponding position data of the drone. A second mission area covering the rough position is generated based on the rough position. The second mission area is smaller than the buried metal object mission area.

[0062] Specifically, based on the difference in the probe data on both sides of the UAV, it is possible to determine whether there is magnetic material in the mission site, and preliminarily lock the rough location of the buried metal object after superimposing the position data. The smaller second mission area generated reduces the detection range, laying the foundation for subsequent more detailed and targeted detection, avoiding blind detection in the entire large mission area, and improving the accuracy and efficiency of subsequent detection.

[0063] Step S32, generating a precise detection route and a corresponding second flight parameter group based on the second mission area, wherein the speed in the second flight parameter group is lower than the speed in the flight parameters of the previous metal buried object mission area, and / or the altitude in the second flight parameter group is lower than the altitude in the flight parameters of the previous metal buried object mission area.

[0064] Based on the second mission area determined in the previous step, a precise detection route and a corresponding second set of flight parameters are generated, allowing the drone to conduct a more detailed exploration of the mission area. Simultaneously, flight parameters are adjusted, reducing speed and / or altitude, allowing the drone ample time to collect data during flight and allowing it to fly closer to the ground, obtaining more accurate magnetic induction intensity data. This helps further improve detection accuracy and paves the way for the subsequent determination of the precise location of buried metal objects.

[0065] Step S33: After loading the drone, it performs a simulated ground flight over the second mission area and records the second magnetic induction intensity data in real time. Based on the difference in the probe data on both sides of the drone, the corresponding position data of the drone is superimposed to obtain the precise location of the buried metal object.

[0066] Specifically, a simulated ground flight was conducted in a smaller and more targeted second mission area and new data was recorded. Combined with the analysis of probe data difference changes, more interference factors were eliminated, the magnetic field characteristic changes generated by buried metal objects were accurately captured, and the position of buried metal objects was accurately locked, which improved the accuracy and measurement efficiency of the entire detection work and met the needs of accurate positioning of buried metal objects in practical applications.

[0067] In this embodiment, step S3 also includes: drawing a magnetic anomaly field contour map and a magnetic anomaly field three-dimensional map of the detection area based on the corrected magnetic induction intensity data of the mission site obtained, and evaluating the location and burial form of the buried metal object based on the different magnetic characteristics presented in the magnetic anomaly field three-dimensional map.

[0068] Specifically, by creating contour maps and three-dimensional graphs, the distribution of the magnetic field within the detection area and any anomalies are intuitively and visually presented, allowing relevant personnel to clearly understand key information such as the changes in magnetic field strength and the distribution of anomaly areas. Based on the magnetic characteristics in the three-dimensional magnetic anomaly field map, not only can the exact location of buried metal objects be further confirmed, but their burial form, such as block, strip, horizontal placement, or tilted placement, can also be roughly inferred. This provides a more comprehensive and detailed reference for subsequent excavation and research, enriching the understanding of buried metal objects and enhancing the value and significance of the entire detection work.

[0069] In another embodiment, the present invention also discloses a magnetic detection drone, such as Figure 5As shown, the invention comprises a rotor UAV body 1, a controller mounted on the body, a crossbar bracket 3 detachably connected to the bottom of the body, two magnetic detection sensors 4 mounted on both ends of the crossbar bracket, and a terminal station capable of communicating with the controller. The controller is configured to: when the UAV is in a static parking state, select an open static magnetic field interference area adjacent to the task area of ​​the buried metal object to be detected for calibration, activate the magnetic detection sensors mounted on both sides of the UAV to record the magnetic induction intensity data of the current environment; start the UAV and record the flight status data of the UAV in real time, the flight status data including position information, speed information and current information of each motor; The UAV is controlled to perform magnetic compensation flight along a preset trajectory, wherein the magnetic detection sensor collects magnetic induction intensity data in real time until magnetic compensation is completed; a ground-simulating flight is performed over a metal buried object mission area according to a set mission route, and the magnetic induction intensity data is recorded in real time; the terminal station is configured to: use magnetic compensation parameters to eliminate environmental interference data and interference data during the UAV maneuvering process from the magnetic induction intensity data collected along the mission route, thereby obtaining corrected magnetic induction intensity data for the mission site; and locate whether the mission site contains magnetic material based on the difference in probe data on both sides of the UAV, and obtain the position of the metal buried object by superimposing the corresponding position data of the UAV.

[0070] In this embodiment, the controller is configured to: after the UAV is started, control the UAV to climb to the set magnetic compensation route starting altitude, enter the magnetic compensation flight mode, and collect and record the magnetic sensor measurement data in real time until the magnetic compensation flight mode ends; the magnetic compensation flight mode is configured to randomly select a starting route direction from the quadrilateral of due east, south, west, and north, perform compensation maneuvers and collect magnetic declination variables, and after the compensation maneuver in each route direction is completed, turn clockwise or counterclockwise to the next route direction, wherein the compensation maneuver is set to sequentially perform a set number of positive and negative angles of rolling with the X-axis as the center axis, a set number of positive and negative angles of pitching with the Y-axis as the center axis, and a set number of positive and negative angles of yaw with the Z-axis as the center axis. The amplitude of the movement is based on the maximum declination angle that can be caused by normal maneuvering of the aircraft. A deviation angle close to the actual maximum flight angle can be measured to be closer to the actual flight self-noise, thereby effectively compensating.

[0071] In this embodiment, the terminal station is further configured to locate whether the mission site contains magnetic materials based on the difference change in the probe data on both sides of the drone, obtain the rough position of the buried metal object after superimposing the corresponding position data of the drone, and generate a second mission area covering the rough position based on the rough position, wherein the second mission area is smaller than the buried metal object mission area; generate a precise detection route and a corresponding second flight parameter group based on the second mission area, wherein the speed in the second flight parameter group is lower than the speed in the flight parameters of the previous buried metal object mission area, and / or the altitude in the second flight parameter group is lower than the altitude in the flight parameters of the previous buried metal object mission area; after the controller loads the precise detection route and the second flight parameter group data sent by the terminal station, it performs a ground-simulating flight over the second mission area and records the second magnetic induction intensity data in real time; the terminal station obtains the precise position of the buried metal object by superimposing the corresponding position data of the drone based on the difference change in the probe data on both sides in the received second magnetic induction intensity data.

[0072] In this embodiment, the terminal station is also configured to draw a magnetic anomaly field contour map and a three-dimensional magnetic anomaly field map of the detection area based on the corrected magnetic induction intensity data of the mission site obtained, and evaluate the location and burial form of the buried metal objects based on the different magnetic characteristics presented in the three-dimensional magnetic anomaly field map.

[0073] In this embodiment, the crossbar bracket 3 includes a first rod 31, a second rod 32 and a third rod 33. The first rod 31 is fixedly connected to the rotor UAV body bracket, and the two ends of the first rod 31 are foldably connected to one end of the second rod 32 and one end of the third rod 33 respectively. The other end of the second rod 32 is detachably connected to a magnetic detection sensor through a magnetic detection mounting seat 34, and the other end of the third rod 33 is detachably connected to another magnetic detection sensor through a magnetic detection mounting seat. When the UAV is stored, the crossbar bracket can be detached from the UAV body and placed as shown in the figure. Figure 6 Fold as shown.

[0074] In this embodiment, if Figure 7As shown, the magnetic probe mount 34 includes a connecting portion 341 connected to the end of the rod body, multiple sets of clamping arms 342 connected to the side of the connecting portion away from the rod body, and a base 343 located below the clamping arms. A storage and limiting structure protrudes upward from the upper portion of the connecting portion. The storage and limiting structure includes a top plate 3441, side blocking plates 3442, and a front blocking plate 3443. The upper wall of the connecting portion, together with the top plate, side blocking plates, and front blocking plates, forms a storage cavity for accommodating the magnetic probe sensor connector. A wire groove 3443 is formed in the upper side of the front blocking plate, recessed toward the side blocking plates. A protrusion for connecting wires is provided on the upper side of the magnetic sensor, extending laterally. The side of the protrusion can be connected to the wires connected to the controller, etc. When installing the magnetic sensor, the magnetic sensor can be quickly inserted into the base through a flexible clamping arm. After being inserted into place, the magnetic sensor is rotated so that the protrusion enters the storage cavity until the wire is stuck in the wire groove. When the protrusion is stuck in the storage cavity, the magnetic sensor can be restricted from being separated from the magnetic probe mounting seat, ensuring that the magnetic sensor can remain stable even when the drone performs bumpy flight actions. In addition, the wire position is also constrained by the wire groove to prevent it from being blown by the rotation of the blades.

[0075] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

[0076] In short, the above description is only a preferred embodiment of the present invention, and all equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the patent of the present invention.

Claims

1. A method for detecting buried metal objects based on drones, characterized in that: The steps include: S1: When the UAV is in a static parking state, select an open static magnetic field interference area near the task area of ​​metal buried objects to be detected for calibration, and start the magnetic detection sensors on both sides of the UAV to record the magnetic induction intensity data of the current environment; S2, starting the UAV and recording the UAV's flight status data in real time, wherein the flight status data includes position information, speed information, and current information of each motor; controlling the UAV to perform magnetic compensation flight along a preset trajectory, wherein the magnetic detection sensor collects magnetic induction intensity data in real time until magnetic compensation is completed; S3: Perform a simulated ground flight over the metal buried object mission area according to the set mission route and record the magnetic induction intensity data in real time. Use magnetic compensation parameters to eliminate the environmental interference data in the mission route and the interference data during the UAV maneuvering process to obtain the corrected magnetic induction intensity data of the mission site. Based on the difference in the probe data on both sides of the UAV, locate whether the mission site contains magnetic materials, and obtain the location of the metal buried object by superimposing the corresponding position data of the UAV.

2. The method for detecting buried metal objects based on drones according to claim 1, characterized in that: The method comprises the following steps, wherein step S2 specifically comprises: After the drone is started, it is controlled to climb to the set starting altitude of the magnetic compensation route and enter the magnetic compensation flight mode. The magnetic sensor measurement data is collected and recorded in real time until the magnetic compensation flight mode ends. The magnetic compensation flight mode is configured to randomly select a starting route direction in the quadrilateral of east, south, west and north, perform compensation maneuvers and collect magnetic declination variables, and after the compensation maneuver in each route direction is completed, turn clockwise or counterclockwise to proceed to the next route direction. The compensation maneuver is set to sequentially perform a set number of positive and negative angle rolls with the X-axis as the center axis, a set number of positive and negative angle pitches with the Y-axis as the center axis, and a set number of positive and negative angle yaws with the Z-axis as the center axis. The amplitude of the movement is based on the maximum declination angle that can be caused by normal maneuvering of the aircraft. A movement close to the actual maximum angle of flight can measure self-noise closer to the actual flight, thereby effectively compensating for it.

3. The method for detecting buried metal objects based on drones according to claim 2, characterized in that: The method comprises the following steps, wherein step S3 further comprises: Based on the difference in the probe data on both sides of the drone, the mission site is located to determine whether there is any magnetic material. The corresponding position data of the drone is superimposed to obtain the rough position of the buried metal object. Based on the rough position, a second mission area covering the rough position is generated. The second mission area is smaller than the buried metal object mission area. Generating a precise detection route and a corresponding second flight parameter set based on the second mission area, wherein the speed in the second flight parameter set is lower than the speed in the flight parameters of the previous buried metal object mission area, and / or the altitude in the second flight parameter set is lower than the altitude in the flight parameters of the previous buried metal object mission area; After being loaded onto the drone, it will conduct a simulated ground flight over the second mission area and record the second magnetic induction intensity data in real time. Based on the difference in the probe data on both sides of the drone, the corresponding position data of the drone will be superimposed to obtain the precise location of the buried metal object.

4. The method for detecting buried metal objects based on drones according to claim 3, characterized in that: The method comprises the following steps, wherein step S3 further comprises: Based on the corrected magnetic induction intensity data obtained from the mission site, the magnetic anomaly field contour map and the magnetic anomaly field three-dimensional map of the detection area are drawn. Based on the different magnetic characteristics presented in the magnetic anomaly field three-dimensional map, the location and burial form of the metal buried objects are evaluated.

5. A magnetic detection drone, characterized in that: The invention comprises a rotor UAV body, a controller mounted on the body, a crossbar bracket detachably connected to the bottom of the body, two magnetic detection sensors respectively mounted at both ends of the crossbar bracket, and a terminal station capable of communicating with the controller, wherein the controller is configured as follows: When the drone is in a static parking state, select an open static magnetic field interference area near the task area of ​​metal buried objects to be detected for calibration, and start the magnetic detection sensors on both sides of the drone to record the magnetic induction intensity data of the current environment; The drone is started and flight status data of the drone is recorded in real time, including position information, speed information, and current information of each motor. The drone is controlled to fly along a preset trajectory to perform magnetic compensation, wherein the magnetic detection sensor collects magnetic induction intensity data in real time until magnetic compensation is completed. The drone is then flown over the metal buried object mission area according to a preset mission route, and magnetic induction intensity data is recorded in real time. The terminal station is configured to: use magnetic compensation parameters to eliminate environmental interference data in the magnetic induction intensity data collected during the mission route and interference data during the UAV maneuvering process, and obtain corrected magnetic induction intensity data of the mission site; locate whether the mission site contains magnetic materials based on the difference change of the probe data on both sides of the UAV, and obtain the position of the buried metal object by superimposing the corresponding position data of the UAV.

6. The magnetic detection drone according to claim 5, characterized in that: The controller is configured to: After the UAV is started, the UAV is controlled to climb to the set magnetic compensation route starting altitude, enters the magnetic compensation flight mode, and collects and records the magnetic sensor measurement data in real time until the magnetic compensation flight mode ends; the magnetic compensation flight mode is configured to randomly select a starting route direction in the quadrilateral of due east, south, west and north, implement compensation maneuvers and collect magnetic declination variables, and after the compensation maneuver in each route direction is completed, turn clockwise or counterclockwise to the next route direction, wherein the compensation maneuver is set to sequentially perform a set number of positive and negative angles of rolling with the X-axis as the center axis, a set number of positive and negative angles of pitching with the Y-axis as the center axis, and a set number of positive and negative angles of yaw with the Z-axis as the center axis. The amplitude of the movement is based on the maximum declination angle that can be caused by normal maneuvering of the aircraft. A movement close to the actual maximum flight angle can measure self-noise closer to the actual flight, thereby effectively compensating.

7. The magnetic detection drone according to claim 6, characterized in that: The terminal station is further configured to locate the presence of magnetic material in the mission site based on a difference in probe data from both sides of the drone, superimpose the corresponding position data of the drone to obtain a rough position of the buried metal object, and generate a second mission area covering the rough position based on the rough position, wherein the second mission area is smaller than the buried metal object mission area; Generating a precise detection route and a corresponding second flight parameter set based on the second mission area, wherein the speed in the second flight parameter set is lower than the speed in the flight parameters of the previous buried metal object mission area, and / or the altitude in the second flight parameter set is lower than the altitude in the flight parameters of the previous buried metal object mission area; After the controller loads the precise detection route and the second flight parameter group data sent by the terminal station, it performs a ground simulation flight over the second mission area and records the second magnetic induction intensity data in real time; The terminal station obtains the precise location of the buried metal object by superimposing the corresponding position data of the drone based on the difference change of the probe data on both sides in the second magnetic induction intensity data received.

8. The magnetic detection drone according to claim 7, characterized in that: The method includes the following steps: the terminal station is further configured to draw a magnetic anomaly field contour map and a magnetic anomaly field three-dimensional map of the detection area based on the corrected magnetic induction intensity data of the mission site obtained, and evaluate the location and burial form of the buried metal objects based on the different magnetic characteristics presented in the magnetic anomaly field three-dimensional map.

9. The magnetic detection drone according to claim 8, characterized in that: The crossbar bracket includes a first rod body, a second rod body and a third rod body. The first rod body is fixedly connected to the rotor UAV body bracket, and the two ends of the first rod body are foldably connected to one end of the second rod body and one end of the third rod body respectively. The other end of the second rod body is detachably connected to a magnetic detection sensor through a magnetic detection mounting base, and the other end of the third rod body is detachably connected to another magnetic detection sensor through a magnetic detection mounting base.

10. The magnetic detection drone according to claim 9, characterized in that: The magnetic probe mounting seat includes a connecting part connected to the end of the rod body, multiple groups of clamping arms connected to the side of the connecting part away from the rod body, and a base located below the clamping arm. The upper part of the connecting part is provided with a storage limit structure protruding upward, and the storage limit structure includes a top plate, a side blocking plate and a front blocking plate. The upper wall of the connecting part is surrounded by the top plate, the side blocking plate and the front blocking plate to form a storage cavity for accommodating the magnetic probe sensor connector. The upper edge of the front blocking plate is provided with a wire groove recessed toward the side blocking plate.

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