Magnetic source high-precision positioning method and device based on single vector sensor space maneuvering

Abstract

The invention discloses a magnetic source high-precision positioning method and device based on single vector sensor space maneuvering, and aims to solve the problems that a traditional magnetic gradient tensor positioning method depends on a sensor array, error correction is complex, and the positioning precision is low due to the fact that the traditional magnetic gradient tensor positioning method is easily interfered by a geomagnetic field. The invention provides a magnetic source high-precision positioning device and method based on single vector sensor space maneuvering. According to the scheme, a single-vector magnetic sensor is controlled to carry out maneuvering measurement at six preset spatial symmetrical measurement points, a magnetic gradient tensor is constructed by utilizing differential operation of magnetic field data of each measurement point, and sensor device errors and environmental interference are decoupled through two times of differential processing of measurement data at different positions, so that the measurement accuracy is improved. And finally, the accurate three-dimensional position of the magnetic source is calculated. According to the method, the hardware structure is simplified, complex correction is not needed, stable and high-precision positioning can still be kept under various error working conditions, and the method is suitable for magnetic target detection in the fields of aerospace and military national defense.

Description

A method and apparatus for high-precision positioning of magnetic sources based on single-vector sensor space maneuvering Technical Field

[0001] This invention belongs to the field of magnetic source detection and positioning technology, and particularly relates to a high-precision positioning method and device for magnetic sources based on spatial maneuvering using a single vector sensor. Background Technology

[0002] Magnetic source detection and inversion technology has significant application value in aerospace, military defense, and other fields. Its core lies in achieving high-precision positioning of magnetic sources through the magnetic gradient tensor. Currently, the measurement of the magnetic gradient tensor mainly relies on a fixed array composed of multiple magnetic sensors. However, this traditional method faces many challenges in practical engineering applications. First, the manufacturing and installation process of the sensor array inevitably introduces proportionality coefficient errors, non-orthogonality errors, and installation alignment errors. To eliminate these systematic errors, a complex calibration process must be performed before or during use. This calibration process itself is highly susceptible to changes in the geomagnetic field spatial gradient and random environmental magnetic interference, leading to inaccurate calibration parameters and a significant decrease in measurement accuracy.

[0003] Secondly, under complex operating conditions with the aforementioned multiple errors, traditional sensor array-based positioning algorithms are prone to a sharp increase in positioning error and unstable performance. More importantly, the geomagnetic field, as a powerful background interference, is difficult to completely separate in traditional correction methods, resulting in indistinguishable interference components in the output signal of the sensor array. This makes the detection of weak magnetic targets against a strong geomagnetic background extremely difficult. These factors collectively limit the real-time high-precision positioning capability of magnetic gradient tensor technology, making it difficult to meet the stringent requirements of modern military reconnaissance, unexploded ordnance detection, and other fields for rapid and accurate positioning of concealed magnetic targets.

[0004] The difficulty in solving the above problems lies in the fact that, on the one hand, attempting to reduce errors by optimizing the processing and assembly technology of sensor arrays is costly and has limited effectiveness; on the other hand, developing more complex online calibration algorithms increases system complexity and affects real-time performance. Therefore, how to significantly simplify the system hardware structure, completely avoid complex calibration processes, and effectively resist environmental interference such as the geomagnetic field while ensuring high accuracy has become a technical bottleneck that urgently needs to be overcome in this field. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention proposes a high-precision positioning method and apparatus for magnetic sources based on single-vector sensor spatial maneuvering, thereby resolving the issues present in the prior art.

[0006] In a first aspect, to achieve the above objectives, the present invention provides a method and apparatus for high-precision positioning of a magnetic source based on spatial maneuvering using a single vector sensor, comprising the following steps:

[0007] Set up spatially symmetrical measuring points centered on a point in the target detection area;

[0008] The single-vector magnetic sensor is controlled to move sequentially to each center point and spatial measuring point, and magnetic field data of each measuring point is collected.

[0009] Based on the magnetic field data from symmetrical measurement points, a magnetic gradient tensor is constructed through difference operations.

[0010] By selecting measurement data from two different spatial locations, differential processing is used to decouple system errors from environmental interference.

[0011] Based on the decoupled magnetic gradient tensor and magnetic field data, the position coordinates of the magnetic source are calculated.

[0012] Optionally, the process of setting up spatially symmetrical measuring points includes: taking a point in the detection area as a reference point, setting up one measuring point in each of the positive and negative directions of the three mutually perpendicular axes in the three-dimensional coordinate system, forming six symmetrically distributed measuring points including the reference point.

[0013] Optionally, the process of controlling the movement of the sensor and collecting magnetic field data includes: driving the single-vector magnetic sensor to sequentially reach the center point and each spatially symmetrical measurement point; at each measurement point, keeping the sensor attitude unchanged or performing attitude compensation, and recording the three-dimensional magnetic field data and spatial coordinate data of that measurement point.

[0014] Optionally, the process of constructing the magnetic gradient tensor includes: differentiating the magnetic field measurements of two symmetrical measurement points located in the positive and negative directions of the same coordinate axis, dividing by the distance between the two measurement points to calculate the magnetic field gradient component of that axis, and combining the gradient components of all axes to form the magnetic gradient tensor.

[0015] Optionally, the process of decoupling errors through differential processing includes: obtaining the magnetic gradient tensor and magnetic field vector measured and constructed by the sensor at two different center positions; establishing the differential equation between the magnetic gradient tensor, magnetic field vector and sensor displacement at the two positions; and canceling the sensor error coefficient and background magnetic field by solving the equation.

[0016] Optionally, the distance between the symmetrical measuring point and the center point is an adjustable baseline length.

[0017] Secondly, the present invention also provides a high-precision magnetic source positioning device based on single-vector sensor spatial maneuvering, for implementing a high-precision magnetic source positioning method based on single-vector sensor spatial maneuvering, the device comprising:

[0018] The measuring point layout module is used to set up spatially symmetrical measuring points centered on a point in the target detection area.

[0019] The motion control and acquisition module is used to control the single-vector magnetic sensor to move sequentially to the center point and the spatial measurement point, and to acquire the magnetic field data of each measurement point;

[0020] The tensor construction module is used to construct a magnetic gradient tensor based on the magnetic field data from symmetrical measurement points through difference operations.

[0021] The error decoupling module is used to select measurement data from two different spatial locations and decouple system errors from environmental interference through differential processing.

[0022] The positioning and solving module is used to calculate the position coordinates of the magnetic source based on the decoupled magnetic gradient tensor and magnetic field data.

[0023] Thirdly, the present invention also provides a computer terminal device, comprising:

[0024] One or more processors;

[0025] A memory, coupled to the processor, for storing one or more programs;

[0026] When the one or more programs are executed by the one or more processors, the one or more processors implement the steps of the high-precision positioning method for magnetic sources based on single-vector sensor spatial maneuvering in the first aspect described above.

[0027] Fourthly, the present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, it implements the steps of the high-precision positioning method for a magnetic source based on a single-vector sensor spatial maneuver described in the first aspect above.

[0028] Fifthly, the present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the high-precision positioning method for a magnetic source based on single-vector sensor spatial maneuver described in the first aspect above.

[0029] Compared with the prior art, the present invention has the following advantages and technical effects:

[0030] This invention provides a high-precision magnetic source positioning method and device based on single-vector sensor space maneuvering. By using single-vector sensor space maneuvering measurement and differential data processing, it effectively overcomes the shortcomings of traditional magnetic gradient tensor positioning technology. This invention simplifies hardware configuration, avoids the complex installation, alignment, and calibration processes of multi-sensor arrays, and reduces system cost and operational complexity. Through symmetrical measurement point layout and two differential calculations, it can automatically cancel sensor scale factor errors, non-orthogonality errors, installation alignment errors, and environmental interferences such as hard magnetic interference, zero-point drift, and geomagnetic field disturbances, achieving automatic error decoupling without the need for additional correction devices or complex calibration. This method maintains stable high-precision positioning capability under various complex error conditions, is highly adaptable to changes in measurement baseline length, and can be flexibly mounted on mobile platforms such as UAVs, meeting the stringent requirements of aerospace, military, and defense fields for high-precision, high-reliability, and real-time detection of magnetic targets. Attached Figure Description

[0031] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0032] Figure 1 is a flowchart illustrating a high-precision positioning method for a magnetic source based on spatial maneuvering using a single vector sensor, according to an embodiment of the present invention.

[0033] Figure 2 is a spatial measurement point diagram of an embodiment of the present invention;

[0034] Figure 3 is a schematic diagram of a high-precision magnetic source positioning device based on single-vector sensor spatial maneuver using a stabilized gimbal according to an embodiment of the present invention.

[0035] Figure 4 is a schematic diagram of a high-precision magnetic source positioning device based on single-vector sensor space maneuvering using a strapdown inertial navigation module according to an embodiment of the present invention. Detailed Implementation

[0036] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0037] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0038] Example 1

[0039] As shown in Figure 1, this embodiment provides a high-precision positioning method for a magnetic source based on single-vector sensor spatial maneuvering, including:

[0040] Set up spatially symmetrical measuring points centered on a point in the target detection area;

[0041] The single-vector magnetic sensor is controlled to move sequentially to each center point and spatial measuring point, and magnetic field data of each measuring point is collected.

[0042] Based on the magnetic field data from symmetrical measurement points, a magnetic gradient tensor is constructed through difference operations.

[0043] By selecting measurement data from two different spatial locations, differential processing is used to decouple system errors from environmental interference.

[0044] Based on the decoupled magnetic gradient tensor and magnetic field data, the position coordinates of the magnetic source are calculated.

[0045] Specifically, the implementation process of this embodiment includes:

[0046] Step 1: Mount the positioning device on the drone platform and power it on.

[0047] Step 2: Operate the drone or follow the predetermined route to make the drone hover at each of the 0-6 points of the spatial measuring point array at position 1 and record the magnetic field data and spatial coordinate data. Transmit the above data to the data acquisition and processing module.

[0048] Step 3: Operate the drone or follow the predetermined route to make the drone hover at each of the 0-6 points of the spatial measurement point array at the second position (record the spatial coordinate offset relative to the first position) and record the magnetic field data and spatial coordinate data. Transmit the above data to the data acquisition and processing module.

[0049] Step 4: Calculate the magnetic gradient tensor based on the magnetic field measurement data of the spatial measuring points at positions 1 and 2, and substitute it into formula (4) to obtain the target position relative to the sensor.

[0050] Furthermore, the process of setting up spatially symmetrical measuring points includes: taking a certain point in the detection area as a reference point, setting up one measuring point in each of the positive and negative directions of the three mutually perpendicular axes in the three-dimensional coordinate system, forming six symmetrically distributed measuring points including the reference point.

[0051] Specifically, the implementation process of this embodiment includes:

[0052] Step 1, Measurement point layout: Taking the center of the area where the magnetic source may exist as the origin, set up a three-dimensional coordinate system, and set up 7 measurement points in the positive and negative directions of the x-axis, y-axis, and z-axis, as shown in Figure 2.

[0053] Furthermore, the process of controlling the movement of the sensor and collecting magnetic field data includes: driving the single-vector magnetic sensor to sequentially reach the center point and the spatially symmetrical measurement point; at each measurement point, keeping the sensor attitude unchanged or performing attitude compensation, and recording the three-dimensional magnetic field data and spatial coordinate data of that measurement point.

[0054] Specifically, the implementation process of this embodiment includes:

[0055] First, six symmetrical measuring points are arranged in the positive and negative directions of the three axes of the three-dimensional coordinate system, with the detection center point as the reference. After the single vector sensor collects the magnetic field data of each measuring point in the order of 0-->1-->5-->4-->2-->6-->3 (or a similar order), the magnetic gradient tensor is quickly constructed through differential operation. The measurement data of any two measuring points are selected for secondary differential analysis. During the measurement process, the sensor attitude is kept unchanged, and the algorithm automatically cancels systematic errors and environmental interferences such as hard magnetic interference, zero-point offset, and geomagnetic field. Finally, the magnetic source position is calculated based on the decoupled effective data.

[0056] Step 2, First Motion Measurement: The coordinates of the central measuring point are r1=(x, y, z). The UAV, equipped with a single-vector magnetic sensor, moves sequentially to seven measuring points. The attitude is maintained by a stabilizing gimbal or a strapdown attitude module, which measures the sensor's attitude in real time. Each measuring point is held for a preset time to collect stable three-dimensional magnetic field data, which is then transmitted to the data processing module. The data collected at each measuring point is averaged to reduce noise interference. If a strapdown attitude module is used, the data is rotated and aligned to the same coordinate system.

[0057] Step 3, Tensor G1 Construction: The data processing module performs differential calculations on the magnetic field data of the positive and negative measurement points on the x-axis, y-axis, and z-axis according to formula (1), automatically canceling the influence of hard magnetic interference, zero-point offset, and errors caused by the geomagnetic field, and obtaining the key independent elements of the magnetic gradient tensor to complete the tensor construction.

[0058] Furthermore, the process of constructing the magnetic gradient tensor includes: differentiating the magnetic field measurements of two symmetrical measurement points located in the positive and negative directions of the same coordinate axis, dividing by the distance between the two measurement points to calculate the magnetic field gradient component of that axis, and combining the gradient components of all axes to form the magnetic gradient tensor.

[0059] Specifically, the implementation process of this embodiment includes:

[0060] Let G be the magnetic field vector at point 0. Then the formula for calculating the magnetic gradient tensor G is:

[0061] (1).

[0062] Furthermore, the process of decoupling errors through differential processing includes: obtaining the magnetic gradient tensor and magnetic field vector measured and constructed by the sensor at two different center positions; establishing the differential equation between the magnetic gradient tensor, magnetic field vector and sensor displacement at the two positions; and canceling the sensor error coefficient and background magnetic field by solving the equation.

[0063] Specifically, the implementation process of this embodiment includes:

[0064] Step 4: Within a distance of M meters from the center point of the first mobile measurement, select the center point of the second mobile measurement, r2=(x+D1, y+D2, z+D3), and repeat steps 2 and 3 to construct tensor G2.

[0065] Positioning calculation: Based on the decoupled magnetic gradient tensor and effective magnetic field data, the three-dimensional position coordinates of the magnetic source are calculated through the positioning algorithm to achieve high-precision positioning.

[0066] According to Euler's equations:

[0067] (2);

[0068] (3);

[0069] Subtracting both sides of equation (2) from equation (3) gives:

[0070] (4);

[0071] Where n represents the target construction index (3 for a magnetic dipole); T represents the regional background field, which can generally be considered a constant; and K represents the sensor error coefficient matrix. Solving for r1 yields the result.

[0072] In this embodiment, under complex working conditions with scale factor error, non-orthogonality error, installation alignment error and geomagnetic field interference, the positioning error is better than the traditional sensor array magnetic gradient tensor positioning method, and no correction operation is required, which fully meets the requirements of engineering application.

[0073] Example 2

[0074] Based on the same general inventive concept, this invention also provides a high-precision magnetic source positioning device based on single-vector sensor spatial maneuvering. The high-precision magnetic source positioning device based on single-vector sensor spatial maneuvering provided by this invention will be described below. The high-precision magnetic source positioning device based on single-vector sensor spatial maneuvering described below can be referred to in correspondence with the high-precision magnetic source positioning method based on single-vector sensor spatial maneuvering described above. The device includes:

[0075] The measuring point layout module is used to set up spatially symmetrical measuring points centered on a point in the target detection area.

[0076] The motion control and acquisition module is used to control the single-vector magnetic sensor to move sequentially to each center point and spatial measuring point, and to acquire the magnetic field data of each measuring point;

[0077] The tensor construction module is used to construct a magnetic gradient tensor based on the magnetic field data from symmetrical measurement points through difference operations.

[0078] The error decoupling module is used to select measurement data from two different spatial locations and decouple system errors from environmental interference through differential processing.

[0079] The positioning and solving module is used to calculate the position coordinates of the magnetic source based on the decoupled magnetic gradient tensor and magnetic field data.

[0080] Specifically, the implementation process of this embodiment includes:

[0081] This device includes a three-axis vector magnetic sensor, a three-axis stabilized gimbal or strapdown inertial navigation module, a data acquisition and processing module, and an unmanned aerial vehicle platform with a high-precision positioning module (such as RTK).

[0082] If a stable gimbal is used, the data acquisition and processing module simultaneously receives 3D coordinate data from the magnetic sensor and the high-precision positioning module; if a strapdown inertial navigation system is used, the data acquisition and processing module receives data from the magnetic sensor, 3D coordinates from the high-precision positioning module, and attitude data from the strapdown inertial navigation system, and outputs the target positioning coordinates after processing.

[0083] Figure 3 shows the high-precision positioning device for the magnetic source, which uses a stable gimbal. Figure 4 shows the high-precision positioning device for the magnetic source, which uses a strapdown inertial navigation module. It adopts a simplified architecture of "single vector sensor + motion control + data processing", which eliminates the need for complex installation and calibration of multi-sensor arrays. The single vector magnetic sensor is driven to move between 6 symmetrical measurement points through the motion control module, thus avoiding the alignment error problem between array sensors.

[0084] Example 2 (equivalent to Example 2 above)

[0085] In this embodiment, a computer terminal device is provided, including:

[0086] One or more processors;

[0087] A memory, coupled to the processor, for storing one or more programs;

[0088] When the one or more programs are executed by the one or more processors, the one or more processors implement the steps of the above-described method for high-precision positioning of magnetic sources based on single-vector sensor spatial maneuvering.

[0089] In this embodiment, a computer-readable storage medium is also provided, on which a computer program is stored. When the computer program is executed by a processor, it implements the steps of the above-described high-precision positioning method for a magnetic source based on single-vector sensor spatial maneuvering.

[0090] In this embodiment, a computer program product is also provided, including a computer program that, when executed by a processor, implements the steps of the above-described high-precision positioning method for a magnetic source based on single-vector sensor spatial maneuvering.

[0091] This invention provides a high-precision magnetic source positioning method and device based on single-vector sensor space maneuvering. By using single-vector sensor space maneuvering measurement and differential data processing, it effectively overcomes the shortcomings of traditional magnetic gradient tensor positioning technology. This invention simplifies hardware configuration, avoids the complex installation, alignment, and calibration processes of multi-sensor arrays, and reduces system cost and operational complexity. Through symmetrical measurement point layout and two differential calculations, it can automatically cancel sensor scale factor errors, non-orthogonality errors, installation alignment errors, and environmental interferences such as hard magnetic interference, zero-point drift, and geomagnetic field disturbances, achieving automatic error decoupling without the need for additional correction devices or complex calibration. This method maintains stable high-precision positioning capability under various complex error conditions, is highly adaptable to changes in measurement baseline length, and can be flexibly mounted on mobile platforms such as UAVs, meeting the stringent requirements of aerospace, military, and defense fields for high-precision, high-reliability, and real-time detection of magnetic targets.

[0092] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A high-precision positioning method for a magnetic source based on spatial maneuvering using a single vector sensor, characterized in that, Includes the following steps: A spatially symmetrical measuring point is set with a certain point in the target detection area as the center point; a single vector magnetic sensor is controlled to move sequentially to each center point and spatial measuring point, and magnetic field data of each measuring point is collected; based on the magnetic field data of the symmetrical measuring point, a magnetic gradient tensor is constructed through differential operation; two measurement data from different spatial locations are selected, and the system error and environmental interference are decoupled through differential processing; based on the decoupled magnetic gradient tensor and magnetic field data, the position coordinates of the magnetic source are calculated.

2. The method according to claim 1, characterized in that, The process of setting up spatially symmetrical measuring points includes: taking a certain point in the detection area as the reference point, setting up one measuring point in each of the positive and negative directions of the three mutually perpendicular axes in the three-dimensional coordinate system, forming six symmetrically distributed measuring points including the reference point.

3. The method according to claim 1, characterized in that, The process of controlling the movement of the sensor and collecting magnetic field data includes: driving the single-vector magnetic sensor to sequentially reach the center point and the spatially symmetrical measurement point; at each measurement point, keeping the sensor attitude unchanged or performing attitude compensation, and recording the three-dimensional magnetic field data and spatial coordinate data of that measurement point.

4. The method according to claim 3, characterized in that, The process of constructing the magnetic gradient tensor includes: differentiating the magnetic field measurements of two symmetrical measurement points located in the positive and negative directions of the same coordinate axis, dividing by the distance between the two measurement points to calculate the magnetic field gradient component of that axis, and combining the gradient components of all axes to form the magnetic gradient tensor.

5. The method according to claim 1, characterized in that, The process of decoupling errors through differential processing includes: obtaining the magnetic gradient tensor and magnetic field vector measured and constructed by the sensor at two different center positions; establishing the differential equation between the magnetic gradient tensor, magnetic field vector and sensor displacement at the two positions; and canceling the sensor error coefficient and background magnetic field by solving the equation.

6. The method according to claim 1, characterized in that, The distance between the symmetrical measuring point and the center point is the adjustable baseline length.

7. A high-precision positioning device for a magnetic source based on spatial maneuvering using a single vector sensor, characterized in that, The apparatus for implementing the method according to any one of claims 1-6 comprises: a measurement point layout module for setting spatially symmetrical measurement points centered on a point in the target detection area; a motion control and acquisition module for controlling a single-vector magnetic sensor to move sequentially to each center point and spatial measurement point, and acquiring magnetic field data at each measurement point; a tensor construction module for constructing a magnetic gradient tensor based on the magnetic field data of the symmetrical measurement points through differential operations; an error decoupling module for selecting measurement data from two different spatial locations and decoupling system errors from environmental interference through differential processing; and a positioning calculation module for calculating the position coordinates of the magnetic source based on the decoupled magnetic gradient tensor and magnetic field data.

8. A computer terminal device, characterized in that, include: One or more processors; A memory, coupled to the processor, for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors perform the steps of the method as described in any one of claims 1-6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1-6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1-6.

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