A magnetic sensor position correction method based on magnetic field gradient optimization

Abstract

The present invention provides a magnetic sensor position correction method based on magnetic field gradient optimization, comprising: installing a DC coil magnetic source on a demagnetization dock, the magnetic source moves in the plane of the demagnetization dock relative to an ideal position of a magnetic sensor to be corrected in a step length of 0.6m along an x ​​or y direction, calculating a magnetic field vertical component of a 0.6m*0.6m*0.6m position deviation area centered at the ideal position of the magnetic sensor to be corrected, calculating the average gradient of the magnetic field vertical component in the x, y and z directions and the magnetic source position coordinates of the position deviation area when the magnetic source position changes each time, determining the calculated magnetic field vertical component with the smallest error from the measured magnetic field vertical component in multiple areas with the largest average gradient in the x, y and z directions, determining a deviation vector of the distance from the actual position to the ideal position, thereby correcting the position of the magnetic sensor according to the deviation vector Δr, and because the magnetic sensor to be corrected is located at a position with a large magnetic field gradient value of the magnetic source by moving the magnetic source, the accuracy of the magnetic sensor position correction is further improved.

Description

Technical Field

[0001] The invention relates to the technical field of magnetic sensor positioning, and in particular to a magnetic sensor position correction method based on magnetic field gradient optimization. Background Art

[0002] Demagnetization is a necessary measure to ensure the safety and combat effectiveness of ships. Accurately measuring the ship's magnetic field is an important prerequisite for implementing demagnetization. At present, the ship's magnetic field is generally measured by magnetic sensors laid on the seabed of the demagnetization station. During the installation of the magnetic sensor at the demagnetization station, the position of the magnetic sensor is generally calibrated by a buoy. However, due to the influence of the marine environment and the complexity of the underwater installation project, there will be a certain deviation between the installation position of the underwater magnetic sensor and the ideal position, which affects the measurement accuracy of the ship's magnetic field. Therefore, the position of the underwater magnetic sensor at the demagnetization station must be corrected to improve the measurement accuracy of the ship's magnetic field.

[0003] The most common method is to locate by sound waves and light, but the semi-enclosed environment and turbid water quality in the degaussing station make it difficult to implement the positioning. Some scholars have proposed: (1) The positioning of ships based on three-axis magnetometers and known magnetic dipoles is used to build an underwater sensor network; (2) Auxiliary solenoid coils are installed on some magnetic sensors to locate the magnetic sensors of dynamic detection stations; (3) The use of sea surface energized coils as magnetic dipole sources and depth sensors is studied to simplify the three-dimensional problem into a two-dimensional problem and then solve the position vector; (4) The position vector analytical expression obtained by the completeness of magnetic dipoles is used to quickly locate the magnetic sensors temporarily deployed at the dynamic detection station; (5) The scalar positioning method based on the modulus solves the influence of background geomagnetic anomalies on magnetic sensors; (6) Underwater positioning methods based on oscillating magnetic fields. These methods provide certain reference significance for the positioning of underwater magnetic sensors at degaussing stations, but it is difficult to meet the centimeter-level positioning requirements of underwater magnetic sensors at degaussing stations. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a magnetic sensor position correction method based on magnetic field gradient optimization which can further improve the accuracy of magnetic sensor position correction.

[0005] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0006] In one general aspect, a method for magnetic sensor position correction based on magnetic field gradient optimization is provided, comprising the following steps:

[0007] Install magnetic sources at degaussing docks;

[0008] The magnetic source is moved in the plane of the demagnetization dock in the x or y direction with a step length of 0.6 m relative to the ideal position of the magnetic sensor to be corrected;

[0009] Calculate the vertical component of the magnetic field in the 0.6m*0.6m*0.6m position deviation area centered on the ideal position of the magnetic sensor to be corrected In the formula, μ 0 represents the vacuum magnetic permeability, m represents the magnetic dipole moment, r(x, y, z) represents the position vector of the ideal position of the position deviation area relative to the magnetic source, Δr d (Δx d , Δy d , Δz d ) represents the position vector of the measurement point in the position deviation area relative to the ideal position;

[0010] Calculate the average gradient of the vertical component of the magnetic field in the x, y and z directions and the coordinates of the magnetic source position in the position deviation area each time the magnetic source position changes; determine the calculated vertical component of the magnetic field with the smallest error from the measured vertical component of the magnetic field in multiple areas with the largest average gradient in the x direction; determine the calculated vertical component of the magnetic field with the smallest error from the measured vertical component of the magnetic field in multiple areas with the largest average gradient in the y direction; determine the calculated vertical component of the magnetic field with the smallest error from the measured vertical component of the magnetic field in multiple areas with the largest average gradient in the z direction;

[0011] The deviation vector Δr (Δx, Δy, Δz) of the distance from the actual position to the ideal position is determined, and the position of the magnetic sensor is corrected according to the deviation vector Δr.

[0012] Further, determining the calculated vertical component of the magnetic field having the smallest error with the measured vertical component of the magnetic field among the multiple regions with the largest average gradient in the x direction specifically includes:

[0013] When determining the s regions with the largest average gradient in the x direction of the position deviation area, the coordinates C of the magnetic source x =[C 1 C 2 …C i …C s ];

[0014] The magnetic source is C 1 Move to C s Position, the magnetic sensor to be corrected measures a set of vertical components of the magnetic field Indicates that the magnetic source is located at C i The vertical component of the magnetic field is measured at the same time through B Z =f(r+Δr x ) is calculated to the deviation vector Δr x The vertical component of the magnetic field of the magnetic sensor to be corrected Indicates that the magnetic source is located at C i The vertical component of the magnetic field calculated when ;

[0015] Calculate the vertical component B of the measured magnetic field zm The calculated vertical component of the magnetic field B zc The error of the vertical component B of the magnetic field is obtained by algorithm optimization. zm The vertical component of the magnetic field B calculated with the smallest error zc .

[0016] Further, determining the calculated vertical component of the magnetic field having the smallest error with the measured vertical component of the magnetic field among the multiple regions with the largest average gradient in the y direction specifically includes:

[0017] When determining the d regions with the largest average gradient in the y direction of the position deviation area, the coordinate G of the magnetic source is y =[G 1 G 2 …G i …G d ];

[0018] The magnetic source is G 1 Move to G d Position, the magnetic sensor to be corrected measures a set of vertical components of the magnetic field Indicates that the magnetic source is located at G i The vertical component of the magnetic field is measured at the same time through B Z =f(r+Δr y ) is calculated to the deviation vector Δr y The vertical component of the magnetic field of the magnetic sensor to be corrected Indicates that the magnetic source is located at G i The vertical component of the magnetic field calculated when ;

[0019] Calculate the vertical component B of the measured magnetic field zn The calculated vertical component of the magnetic field B zg The error of the vertical component B of the magnetic field is obtained by algorithm optimization. zn The vertical component of the magnetic field B calculated with the smallest error zg .

[0020] Further, determining the calculated vertical component of the magnetic field having the smallest error with the measured vertical component of the magnetic field in the plurality of regions having the largest average gradient in the z direction specifically includes:

[0021] When determining the e regions with the largest average gradient in the z direction of the position deviation area, the coordinates H of the magnetic source are x =[H 1 H 2 …H i …H e ];

[0022] The magnetic source is composed of H 1 The position moves to He Position, the magnetic sensor to be corrected measures a set of vertical components of the magnetic field Indicates that the magnetic source is located at H i The vertical component of the magnetic field is measured at the same time through B Z =f(r+Δr z ) is calculated to the deviation vector Δr z The vertical component of the magnetic field of the magnetic sensor to be corrected Indicates that the magnetic source is located at H i The vertical component of the magnetic field calculated when ;

[0023] Calculate the vertical component B of the measured magnetic field zk The calculated vertical component of the magnetic field B zh The error of the vertical component B of the magnetic field is obtained by algorithm optimization. zk The vertical component of the magnetic field B calculated with the smallest error zh .

[0024] Further, determining a deviation vector Δr (Δx, Δy, Δz) of the distance from the actual position to the ideal position, and correcting the position of the magnetic sensor according to the deviation vector Δr specifically includes:

[0025] Minimize the correction function to calculate the measured vertical component of the magnetic field B zm The calculated vertical component of the magnetic field B z The error is obtained, thus obtaining the distance deviation vector Δr from the actual position to the ideal position x (Δx x , Δy x , Δz x ), the Δx x is Δx in the Δr;

[0026] Minimize the correction function to calculate the measured vertical component of the magnetic field B zn The calculated vertical component of the magnetic field B z The error is obtained, thus obtaining the distance deviation vector Δr from the actual position to the ideal position y (Δx y , Δy y , Δz y ), the Δy y is Δy in Δr;

[0027] Minimize the correction function to calculate the measured vertical component of the magnetic field B zk The calculated vertical component of the magnetic field B z The error is obtained, thus obtaining the distance deviation vector Δr from the actual position to the ideal position z (Δx z , Δy z , Δz z), the Δz z is Δz in Δr.

[0028] Furthermore, the correction function in the x direction is Minimize: The correction function in the y direction is Minimize: The correction function in the z direction is Minimize:

[0029] The present invention provides a magnetic sensor position correction method based on magnetic field gradient optimization. By moving the magnetic source, the magnetic sensor to be corrected is located in an area with a large magnetic field gradient value of the magnetic source, thereby further improving the accuracy of the magnetic sensor position correction and having good practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 It is a flow chart of the magnetic sensor position correction method based on magnetic field gradient optimization of the present invention. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the 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.

[0033] Embodiment 1

[0034] Figure 1 is a flow chart of the magnetic sensor position correction method based on magnetic field gradient optimization of the present invention, such as Figure 1 As shown, a magnetic sensor position correction method based on magnetic field gradient optimization in this embodiment includes the following steps:

[0035] Install magnetic sources at degaussing docks;

[0036] The magnetic source is moved in the plane of the demagnetization dock in the x or y direction with a step length of 0.6 m relative to the ideal position of the magnetic sensor to be corrected;

[0037] Calculate the vertical component of the magnetic field in the 0.6m*0.6m*0.6m position deviation area centered on the ideal position of the magnetic sensor to be corrected In the formula, μ 0 represents the vacuum magnetic permeability, m represents the magnetic dipole moment, r(x, y, z) represents the position vector of the ideal position of the position deviation area relative to the magnetic source, Δr d (Δx d , Δy d , Δz d ) represents the position vector of the measurement point in the position deviation area relative to the ideal position;

[0038] Calculate the average gradient of the vertical component of the magnetic field in the x, y and z directions and the coordinates of the magnetic source position in the position deviation area each time the magnetic source position changes;

[0039] Determine the calculated vertical component of the magnetic field having the smallest error with the measured vertical component of the magnetic field among the plurality of regions having the largest average gradient in the x-direction;

[0040] Determine the calculated vertical component of the magnetic field having the smallest error with the measured vertical component of the magnetic field among the plurality of regions having the largest average gradient in the y direction;

[0041] Determine the calculated vertical component of the magnetic field having the smallest error with the measured vertical component of the magnetic field among the plurality of regions having the largest average gradient in the z direction;

[0042] The deviation vector Δr (Δx, Δy, Δz) of the distance from the actual position to the ideal position is determined, and the position of the magnetic sensor is corrected according to the deviation vector Δr.

[0043] Further, determining the calculated vertical component of the magnetic field having the smallest error with the measured vertical component of the magnetic field in the plurality of regions having the largest average gradient in the x-direction specifically includes:

[0044] Determine the center coordinates C of the s regions with the largest average gradient in the x direction x =[C 1 C 2 …C s ];

[0045] When determining the s regions with the largest average gradient in the x direction of the position deviation area, the coordinates C of the magnetic source x =[C 1 C 2 …C i …C s ];

[0046] The magnetic source is C 1 Move to C s Position, the magnetic sensor to be corrected measures a set of vertical components of the magnetic field Indicates that the magnetic source is located at C i The vertical component of the magnetic field is measured at the same time through B Z=f(r+Δr x ) is calculated to the deviation vector Δr x The vertical component of the magnetic field of the magnetic sensor to be corrected Indicates that the magnetic source is located at C i The vertical component of the magnetic field calculated when ;

[0047] Calculate the vertical component B of the measured magnetic field zm The calculated vertical component of the magnetic field B zc The error of the vertical component B of the magnetic field is obtained by algorithm optimization. zm The vertical component of the magnetic field B calculated with the smallest error zc .

[0048] Further, determining the calculated vertical component of the magnetic field having the smallest error with the measured vertical component of the magnetic field in the plurality of regions having the largest average gradient in the y direction specifically includes:

[0049] When determining the d regions with the largest average gradient in the y direction of the position deviation area, the coordinate G of the magnetic source is y =[G 1 G 2 …G i …G d ];

[0050] The magnetic source is G 1 Move to G d Position, the magnetic sensor to be corrected measures a set of vertical components of the magnetic field Indicates that the magnetic source is located at G i The vertical component of the magnetic field is measured at the same time through B Z =f(r+Δr y ) is calculated to the deviation vector Δr y The vertical component of the magnetic field of the magnetic sensor to be corrected Indicates that the magnetic source is located at G i The vertical component of the magnetic field calculated when ;

[0051] Calculate the vertical component B of the measured magnetic field zn The calculated vertical component of the magnetic field B zg The error of the vertical component B of the magnetic field is obtained by algorithm optimization. zn The vertical component of the magnetic field B calculated with the smallest error zg .

[0052] Further, determining the calculated vertical component of the magnetic field having the smallest error with the measured vertical component of the magnetic field in the plurality of regions having the largest average gradient in the z direction specifically includes:

[0053] When determining the e regions with the largest average gradient in the z direction of the position deviation area, the coordinates H of the magnetic source arex =[H 1 H 2 …H i …H e ];

[0054] The magnetic source is composed of H 1 The position moves to H e Position, the magnetic sensor to be corrected measures a set of vertical components of the magnetic field Indicates that the magnetic source is located at H i The vertical component of the magnetic field is measured at the same time through B Z =f(r+Δr z ) is calculated to the deviation vector Δr z The vertical component of the magnetic field of the magnetic sensor to be corrected Indicates that the magnetic source is located at H i The vertical component of the magnetic field calculated when ;

[0055] Calculate the vertical component B of the measured magnetic field zk The calculated vertical component of the magnetic field B zh The error of the vertical component B of the magnetic field is obtained by algorithm optimization. zk The vertical component of the magnetic field B calculated with the smallest error zh .

[0056] Further, determining a deviation vector Δr (Δx, Δy, Δz) of the distance from the actual position to the ideal position, and correcting the position of the magnetic sensor according to the deviation vector Δr specifically includes:

[0057] Minimize the correction function to calculate the measured vertical component of the magnetic field B zm The calculated vertical component of the magnetic field B z The error is obtained, thus obtaining the distance deviation vector Δr from the actual position to the ideal position x (Δx x , Δy x , Δz x ), the Δx x is Δx in the Δr;

[0058] Minimize the correction function to calculate the measured vertical component of the magnetic field B zn The calculated vertical component of the magnetic field B z The error is obtained, thus obtaining the distance deviation vector Δr from the actual position to the ideal position y (Δx y , Δy y , Δz y ), the Δy y is Δy in Δr;

[0059] Minimize the correction function to calculate the measured vertical component of the magnetic field Bzk The calculated vertical component of the magnetic field B z The error is obtained, thus obtaining the distance deviation vector Δr from the actual position to the ideal position z (Δx z , Δy z , Δz z ), the Δz z is Δz in Δr.

[0060] Furthermore, the correction function in the x direction is Minimize: The correction function in the y direction is Minimize: The correction function in the z direction is Minimize:

[0061] The embodiments of this specification provide a magnetic sensor position correction method based on magnetic field gradient optimization. By moving the magnetic source, the magnetic sensor to be corrected is located at a position with a large magnetic field gradient value of the magnetic source, thereby further improving the accuracy of the magnetic sensor position correction and having good practicality.

[0062] A 1.2:10 physical scale model experiment was conducted on this embodiment. A circular current-carrying coil was used as a magnetic source, which was equivalent to a magnetic field pole. A correction simulation experiment was conducted on 5 magnetic sensor position deviation states located at a depth of 1.8 m and 1.2 m wide from the magnetic source. The results are shown in Table 1. The error in the x direction is 0.18 cm, the average error in the y direction is 0.19 cm, the average error in the z direction is 0.48 cm, the average error of the modulus d is 0.56 cm, and the relative error d_re is 0.31% (d_re=d / (1.52+12) 1 / 2 ×100%). Compared with the average error of the existing module value of 1.167cm and the relative error of 1.87%, the positioning accuracy is improved by an order of magnitude.

[0063] Table 1

[0064]

[0065]

[0066] The above is a description of a specific embodiment of the present specification. Other embodiments are within the scope of the appended claims. It should be noted that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of this application, and these improvements and modifications should also be regarded as the scope of protection of this application.

Claims

1. A magnetic sensor position correction method based on magnetic field gradient optimization, characterized in that: The following steps are involved: Install magnetic sources at degaussing docks; The magnetic source is moved in the plane of the demagnetization dock in the x or y direction with a step length of 0.6 m relative to the ideal position of the magnetic sensor to be corrected; Calculate the vertical component of the magnetic field in the 0.6m*0.6m*0.6m position deviation area centered on the ideal position of the magnetic sensor to be corrected Where μ0 represents the vacuum magnetic permeability, m represents the magnetic dipole moment, r(x, y, z) represents the position vector of the ideal position of the position deviation area relative to the magnetic source, and Δr d (Δx d , Δy d , Δz d ) represents the position vector of the measurement point in the position deviation area relative to the ideal position; Calculate the average gradient of the vertical component of the magnetic field in the x, y and z directions and the coordinates of the magnetic source position in the position deviation area each time the magnetic source position changes; determine the calculated vertical component of the magnetic field with the smallest error with the measured vertical component of the magnetic field in multiple areas with the largest average gradient in the x direction; Determine the calculated vertical component of the magnetic field having the smallest error with the measured vertical component of the magnetic field among the plurality of regions having the largest average gradient in the y direction; Determine the calculated vertical component of the magnetic field having the smallest error with the measured vertical component of the magnetic field among the plurality of regions having the largest average gradient in the z direction; The deviation vector Δr (Δx, Δy, Δz) of the distance from the actual position to the ideal position is determined, and the position of the magnetic sensor is corrected according to the deviation vector Δr.

2. The magnetic sensor position correction method based on magnetic field gradient optimization according to claim 1, characterized in that: The vertical component of the magnetic field obtained by calculation and having the smallest error with the measured vertical component of the magnetic field among the multiple regions with the largest average gradient in the x direction specifically includes: When determining the s regions with the largest average gradient in the x direction of the position deviation area, the coordinates C of the magnetic source x =[C1C2…C i …C s ]; Move the magnetic source from position C1 to position C s Position, the magnetic sensor to be corrected measures a set of vertical components of the magnetic field Indicates that the magnetic source is located at C i The vertical component of the magnetic field is measured at the same time through B Z =f(r+Δr x ) is calculated to the deviation vector Δr x The vertical component of the magnetic field of the magnetic sensor to be corrected Indicates that the magnetic source is located at C i The vertical component of the magnetic field calculated when ; Calculate the vertical component B of the measured magnetic field zm The calculated vertical component of the magnetic field B zc The error of the vertical component B of the magnetic field is obtained by algorithm optimization. zm The vertical component of the magnetic field B calculated with the smallest error zc .

3. The magnetic sensor position correction method based on magnetic field gradient optimization according to claim 2, characterized in that: The vertical component of the magnetic field obtained by calculation and having the smallest error with the measured vertical component of the magnetic field among the multiple regions with the largest average gradient in the y direction specifically includes: When determining the d regions with the largest average gradient in the y direction of the position deviation area, the coordinate G of the magnetic source is y =[G1G2…G i …G d ]; Move the magnetic source from position G1 to position G1 in sequence. d Position, the magnetic sensor to be corrected measures a set of vertical components of the magnetic field Indicates that the magnetic source is located at G i The vertical component of the magnetic field is measured at the same time through B Z =f(r+Δr y ) is calculated to the deviation vector Δr y The vertical component of the magnetic field of the magnetic sensor to be corrected Indicates that the magnetic source is located at G i The vertical component of the magnetic field calculated when ; Calculate the vertical component B of the measured magnetic field zn The calculated vertical component of the magnetic field B zg The error of the vertical component B of the magnetic field is obtained by algorithm optimization. zn The vertical component of the magnetic field B calculated with the smallest error zg .

4. The magnetic sensor position correction method based on magnetic field gradient optimization according to claim 3 is characterized in that: The vertical component of the magnetic field obtained by calculation and having the smallest error with the measured vertical component of the magnetic field among the multiple regions with the largest average gradient in the z direction specifically includes: When determining the e regions with the largest average gradient in the z direction of the position deviation area, the coordinates H of the magnetic source are x =[H1H2…H i …H e ]; Move the magnetic source from position H1 to position H1 in sequence. e Position, the magnetic sensor to be corrected measures a set of vertical components of the magnetic field It represents the vertical component of the magnetic field measured when the magnetic source is at Hi, and at the same time, it is measured by B Z =f(r+Δr z ) is calculated to the deviation vector Δr z The vertical component of the magnetic field of the magnetic sensor to be corrected Indicates that the magnetic source is located at H i The vertical component of the magnetic field calculated when ; Calculate the vertical component B of the measured magnetic field zk The calculated vertical component of the magnetic field B zh The error of the vertical component B of the magnetic field is obtained by algorithm optimization. zk The vertical component of the magnetic field B calculated with the smallest error zh .

5. The magnetic sensor position correction method based on magnetic field gradient optimization according to claim 4 is characterized in that: Determining the deviation vector Δr (Δx, Δy, Δz) of the distance from the actual position to the ideal position, thereby correcting the position of the magnetic sensor according to the deviation vector Δr specifically includes: Minimize the correction function to calculate the measured vertical component of the magnetic field B zm The calculated vertical component of the magnetic field B z The error is obtained, thus obtaining the distance deviation vector Δr from the actual position to the ideal position x (Δx x , Δy x , Δz x ), the Δx x is Δx in the Δr; Minimize the correction function to calculate the measured vertical component of the magnetic field B zn The calculated vertical component of the magnetic field B z The error is obtained, thus obtaining the distance deviation vector Δr from the actual position to the ideal position y (Δx y , Δy y , Δz y ), the Δy y is Δy in Δr; Minimize the correction function to calculate the measured vertical component of the magnetic field B zk The calculated vertical component of the magnetic field B z The error is obtained, thus obtaining the distance deviation vector Δr from the actual position to the ideal position z (Δx z , Δy z , Δz z ), the Δz z is Δz in Δr.

6. The magnetic sensor position correction method based on magnetic field gradient optimization according to claim 5, characterized in that: The correction function in the x direction is The correction function in the y direction is The correction function in the z direction is

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