Method, device and equipment for calibrating orthogonality of magnetic axis and mechanical axis and medium

Abstract

The invention provides a magnetic axis and mechanical axis orthogonality calibration method and device, electronic equipment and a medium, the device comprises a Helmholtz coil, a non-magnetic rotary table, two non-magnetic theodolites, a reference cubic mirror and an electronics box, the non-magnetic rotary table is placed in the center of the Helmholtz coil, and the reference cubic mirror is placed in the center of the Helmholtz coil; establishing a rectangular coordinate system aiming at the Helmholtz coil by the two non-magnetic theodolites; a magnetometer to be measured is placed on the non-magnetic rotary table, and a reference cubic mirror is fixed to the top of a shell of a probe of the magnetometer to be measured; the two non-magnetic theodolites are adjusted to be aligned with the cubic mirror, a first rotation field adding value is input into the Helmholtz coil, the non-magnetic rotary table is rotated to measure probe measurement values of the magnetometer to be measured at three positions, the calibrated first rotation field adding value is obtained in combination with the calibration result of the Helmholtz coil, and thus rotation matrixes of the three positions are obtained; and solving two cubic normal directions of the cubic mirror under the sensor coordinate system, and determining an orthogonality calibration result, thereby improving the orthogonality calibration precision.

Description

Technical Field

[0001] The present application relates to the field of vector magnetometers, and more specifically, to a method, device, equipment, and medium for calibrating the orthogonality of a magnetic axis and a mechanical axis. Background Art

[0002] Vector magnetometers are critical components in drones, navigation systems, and other devices requiring precise direction detection. The accuracy of magnetometer detection is crucial. Ideally, the magnetometer's magnetic axis and mechanical axis should be strictly aligned. Misalignment can lead to errors in direction measurement, impacting overall performance. Therefore, calibrating the magnetic and mechanical axes of a magnetic sensor (i.e., a magnetometer) is a critical step in ensuring sensor measurement accuracy. Summary of the Invention

[0003] In view of this, the purpose of this application is to provide a method, device, equipment and medium for calibrating the orthogonality of the magnetic axis and the mechanical axis, which can more accurately calibrate the orthogonality of the magnetic axis and the mechanical axis and improve the overall measurement accuracy of the vector magnetometer.

[0004] An embodiment of the present application provides a method for calibrating the orthogonality of a magnetic axis and a mechanical axis, which is applied to an orthogonality calibration device for a magnetic axis and a mechanical axis. The device comprises: a Helmholtz coil, a non-magnetic turntable, two non-magnetic theodolites, a reference cubic mirror, and an electronics box. The non-magnetic turntable is placed at the center of the Helmholtz coil, and the two non-magnetic theodolites establish a rectangular coordinate system for the Helmholtz coil. The two non-magnetic theodolites include a first non-magnetic theodolite and a second non-magnetic theodolite. The calibration method comprises the following steps: Calibrate the Helmholtz coil and calculate the linearity factor, orthogonality and zero bias of the Helmholtz coil; The magnetometer to be tested is placed on the non-magnetic turntable; wherein a reference cubic mirror is fixed to the top of the housing of the probe of the magnetometer to be tested, and the three cubic faces of the reference cubic mirror represent the normal directions of the three mechanical axes respectively; the probe of the magnetometer to be tested is connected to an electronics box; Adjusting the two non-magnetic theodolites so that the normal directions of the first cubic face and the second cubic face of the cubic mirror are aligned with the two non-magnetic theodolites respectively and meet a preset alignment accuracy; setting a first position after alignment as the alignment of the normal directions of the first cubic face of the first non-magnetic theodolite and the cubic mirror; Inputting a first rotational applied field value to the Helmholtz coil, rotating the non-magnetic turntable, and measuring probe measurement values ​​of a probe of the magnetometer to be measured at three positions, respectively; the three positions are the first position, a second position in which the second non-magnetic theodolite is aligned with the second cubic face of the cubic mirror in a normal direction, and a third position in which the first theodolite is aligned with the second cubic face of the cubic mirror in a normal direction; Calibrate the first rotation added field value based on the linear factor, orthogonality, and zero bias of the Helmholtz coil to obtain a calibrated first rotation added field value, and obtain rotation matrices at three positions based on the calibrated first rotation added field value and probe measurement values ​​at three positions; The first cube face normal and the second cube face normal of the cubic mirror in the sensor coordinate system are solved by the conversion matrix of the three positions, and the orthogonality calibration result is determined based on the first cube face normal and the second cube face normal; the orthogonality calibration result includes: the angular deviation between the first cube face normal and the second cube face normal, and the conversion matrix between the orthogonal matrix based on the magnetic axis and the mechanical axis.

[0005] In some embodiments, in the method for calibrating the orthogonality of the magnetic axis and the mechanical axis, calibrating the Helmholtz coil and calculating the linearity factor, orthogonality, and zero bias of the Helmholtz coil include: Placing a proton magnetometer at the center of the Helmholtz coil and inputting a second rotating added field value into the Helmholtz coil system; the total field of the second rotating added field value is 50,000 nT, and the vector direction is uniformly distributed on a spherical surface; The proton magnetometer data is collected, the coil is calibrated, and the linearity factor, orthogonality and zero bias of the coil are calculated.

[0006] In some embodiments, in the method for calibrating the orthogonality of the magnetic axis and the mechanical axis, adjusting the two non-magnetic theodolites so that the first cubic face normal and the second cubic face normal of the cubic mirror are respectively aligned with the two non-magnetic theodolites and meet a preset alignment accuracy includes: Laser is used to preliminarily align the normal direction of the first cubic face and the normal direction of the second cubic face of the cubic mirror with two non-magnetic theodolites respectively; The position of the non-magnetic turntable is fine-tuned until the alignment accuracy of the cubic mirror and the two non-magnetic theodolites meets the preset alignment accuracy; the preset alignment accuracy is 2 arc seconds.

[0007] In some embodiments, in the method for calibrating the orthogonality of the magnetic axis and the mechanical axis, inputting a first rotating field value to the Helmholtz coil, rotating the non-magnetic turntable, and measuring probe measurement values ​​of the magnetometer under test at three positions respectively include: Input a first rotating field value to the Helmholtz coil system to obtain a probe measurement value of the magnetometer to be measured at a first position. ; rotating the non-magnetic turntable to move the cubic mirror to a second position, and fine-tuning the horizontal plane of the non-magnetic turntable to align the second non-magnetic theodolite with the normal of the second cubic face of the cubic mirror; Input a first rotating field value to the Helmholtz coil system to obtain a probe measurement value of the magnetometer to be measured at a second position. ; Rotating the non-magnetic turntable to move the cubic mirror to a third position, and fine-tuning the horizontal plane of the non-magnetic turntable to align the first non-magnetic theodolite with the normal of the second cubic face of the cubic mirror; Input a first rotating field value to the Helmholtz coil system to obtain a probe measurement value of the magnetometer to be measured at a second position. .

[0008] In some embodiments, in the method for calibrating the orthogonality of the magnetic axis and the mechanical axis, calibrating the first rotating added field value based on the linear factor, orthogonality, and zero bias of the Helmholtz coil to obtain the calibrated first rotating added field value includes: The calibrated first rotation plus field value is calculated based on the following formula (1): ... (1); Among them, the Characterizing the first rotation-added field value of the input; Characterizes the calibrated first rotation field value, Characterize the linear factor, Characterize orthogonality; Characterize zero bias.

[0009] In some embodiments, in the method for calibrating the orthogonality of the magnetic axis and the mechanical axis, obtaining the rotation matrix at the three positions based on the calibrated first rotation field value and the probe measurement values ​​at the three positions includes: The first rotation matrix of the probe measurement value at the first position and the calibrated first rotation plus field value is calculated by the following formula (2): R 1; ... (2); Among them, the a probe measurement representing a first position; R 1 first rotation matrix; The second rotation matrix of the probe measurement value at the second position and the calibrated first rotation plus field value is calculated by the following formula (3): R 2; ... (3); in, a probe measurement representing a second position; R 2 second rotation matrix; The third rotation matrix of the probe measurement value at the third position and the calibrated first rotation plus field value is calculated by the following formula (4): R 3; ……(4); in, a probe measurement representing a third position; R3The third rotation matrix.

[0010] In some embodiments, in the method for calibrating the orthogonality of the magnetic axis and the mechanical axis, solving the first cube face normal and the second cube face normal of the cubic mirror in the sensor coordinate system by using the transformation matrix of three positions, and determining the orthogonality calibration result based on the first cube face normal and the second cube face normal, includes: Calculating a fourth rotation matrix of the magnetometer to be measured from the first position to the second position, and calculating an eigenvector of the fourth rotation matrix; the eigenvector of the fourth rotation matrix is ​​a first cubic face normal of the cubic mirror in the sensor coordinate system; Calculating the direction of the optical rotation axis in the coil coordinate system based on the fourth rotation matrix and the first cube face normal; Calculating a second cubic face normal of the cubic mirror in the sensor coordinate system based on a third rotation matrix corresponding to the third position and the direction of the optical rotation axis; Calculate the angle deviation between the normal direction of the first cubic face and the normal direction of the second cubic face; Based on the first and second cube face normals, a target conversion matrix between the magnetic field of the cubic mirror mechanical coordinate system and the magnetic field of the sensor coordinate system is determined, wherein the target conversion matrix represents a conversion matrix between an orthogonal matrix based on a magnetic axis and a mechanical axis.

[0011] In some embodiments, a device for calibrating the orthogonality of a magnetic axis and a mechanical axis is further provided, the device comprising: a Helmholtz coil, a non-magnetic turntable, two non-magnetic theodolites, a reference cubic mirror, an electronics box, and a processor, wherein the non-magnetic turntable is placed at the center of the Helmholtz coil, and the two non-magnetic theodolites establish a rectangular coordinate system for the Helmholtz coil; the two non-magnetic theodolites include a first non-magnetic theodolite and a second non-magnetic theodolite; During calibration, the magnetometer to be tested is placed on the non-magnetic turntable; a reference cubic mirror is fixed to the top of the housing of the probe of the magnetometer to be tested, and the three cubic faces of the reference cubic mirror represent the normal directions of the three mechanical axes respectively; the probe of the magnetometer to be tested is connected to an electronics box, and the electronics box is connected to the processor; Adjusting the two non-magnetic theodolites so that the normal directions of the first cubic face and the second cubic face of the cubic mirror are aligned with the two non-magnetic theodolites respectively and meet a preset alignment accuracy; setting a first position after alignment as the alignment of the normal directions of the first cubic face of the first non-magnetic theodolite and the cubic mirror; Inputting a first rotational applied field value to the Helmholtz coil, rotating the non-magnetic turntable, and measuring probe measurement values ​​of a probe of the magnetometer to be measured at three positions, respectively; the three positions are the first position, a second position in which the second non-magnetic theodolite is aligned with the second cubic face of the cubic mirror in a normal direction, and a third position in which the first theodolite is aligned with the second cubic face of the cubic mirror in a normal direction; The processor is configured to calibrate the first rotation added field value based on the calibrated linear factor, orthogonality, and zero bias of the Helmholtz coil to obtain a calibrated first rotation added field value, and obtain a rotation matrix at the three positions based on the calibrated first rotation added field value and probe measurement values ​​at the three positions; solve the first cubic face normal and the second cubic face normal of the cubic mirror in the sensor coordinate system through the transformation matrix at the three positions, and determine an orthogonality calibration result based on the first cubic face normal and the second cubic face normal; the orthogonality calibration result includes: an angular deviation between the first cubic face normal and the second cubic face normal, and a magnetic field of a magnetic axis coordinate system and a magnetic field of a mechanical axis coordinate system.

[0012] In some embodiments, an electronic device is also provided, comprising: a processor, a memory, and a bus, wherein the memory stores machine-readable instructions executable by the processor. When the electronic device is running, the processor and the memory communicate through the bus, and when the machine-readable instructions are executed by the processor, the steps of the method for calibrating the orthogonality of the magnetic axis and the mechanical axis are performed.

[0013] In some embodiments, a computer-readable storage medium is further provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method for calibrating the orthogonality of the magnetic axis and the mechanical axis are executed.

[0014] The orthogonality calibration method, device, electronic device, and medium for the magnetic and mechanical axes described in the embodiments of the present application calibrate the Helmholtz coils to reduce the error of the applied known magnetic field. Two non-magnetic theodolites are used to establish a precise rectangular coordinate system. A non-magnetic turntable, laser, and cubic mirror are used to improve the alignment accuracy of the mechanical axis, reduce experimental operation errors, and thereby improve the accuracy of the conversion matrix between the vector magnetometer measurement values ​​and the actual magnetic field measurement values. Based on this, the non-orthogonality of the magnetic and mechanical axes is effectively corrected, improving the overall measurement accuracy of the vector magnetometer. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 A flow chart of a method for calibrating the orthogonality of a magnetic axis and a mechanical axis according to an embodiment of the present application is shown; Figure 2 A flow chart of a method for calculating the linearity factor, orthogonality, and zero bias of the Helmholtz coil according to an embodiment of the present application is shown; Figure 3 A schematic diagram of the rotation positions of the theodolite and the vector magnetometer according to an embodiment of the present application is shown; Figure 4 A flow chart of a method for determining an orthogonality calibration result according to an embodiment of the present application is shown; Figure 5 A schematic diagram of the magnetic field measurement results of the Helmholtz coil calibration according to an embodiment of the present application is shown; Figure 6 An example diagram of the Helmholtz coil calibration according to an embodiment of the present application is shown; Figure 7 An example diagram of the conversion matrix calculation and measurement between the measured value of the magnetometer to be measured and the actual magnetic field measured value according to an embodiment of the present application is shown; Figure 8 A schematic diagram of the coordinate system of the sensor coordinate system and the cubic mirror coordinate system described in an embodiment of the present application is shown; Figure 9 A schematic structural diagram of an electronic device according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of illustration and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application illustrate the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowcharts can be implemented out of sequence, and steps without logical context can be reversed or implemented simultaneously. In addition, those skilled in the art, under the guidance of the contents of this application, can add one or more other operations to the flowchart, or remove one or more operations from the flowchart.

[0018] In addition, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application.

[0019] It should be noted that the term "comprising" will be used in the embodiments of the present application to indicate the existence of the features declared thereafter, but does not exclude the addition of other features.

[0020] Vector magnetometers are critical components in drones, navigation systems, and other devices requiring precise direction detection. The accuracy of magnetometer detection is crucial. Ideally, the magnetometer's magnetic axis and mechanical axis should be strictly aligned. Misalignment can lead to errors in direction measurement, impacting overall performance. Therefore, calibrating the magnetic and mechanical axes of the magnetic sensor (i.e., magnetometer) is a critical step in ensuring sensor measurement accuracy.

[0021] Based on this, in an embodiment of the present application, a method, device, electronic device and medium for calibrating the orthogonality of a magnetic axis and a mechanical axis are provided, which are applied to an orthogonality calibration device for a magnetic axis and a mechanical axis. The device includes: a Helmholtz coil, a non-magnetic turntable, two non-magnetic theodolites, a reference cubic mirror and an electronics box. The non-magnetic turntable is placed at the center of the Helmholtz coil, and the two non-magnetic theodolites establish a rectangular coordinate system for the Helmholtz coil; the two non-magnetic theodolites include a first non-magnetic theodolite and a second non-magnetic theodolite; the calibration method includes the following steps: calibrating the Helmholtz coil, calculating the linear factor, orthogonality and zero value of the Helmholtz coil The invention relates to a method for manufacturing a magnetometer to be measured, wherein the magnetometer to be measured is placed on the non-magnetic turntable; wherein a reference cubic mirror is fixed on the top of the housing of the probe of the magnetometer to be measured, and the three cubic faces of the reference cubic mirror respectively represent the normal directions of the three mechanical axes; the probe of the magnetometer to be measured is connected to an electronics box; the two non-magnetic theodolites are adjusted so that the normal directions of the first cubic face and the second cubic face of the cubic mirror are respectively aligned with the two non-magnetic theodolites and meet the preset alignment accuracy; the first position after alignment is set as the alignment of the first non-magnetic theodolite and the first cubic face of the cubic mirror; the first rotational field value is input into the Helmholtz coil, the non-magnetic turntable is rotated, and the probe of the magnetometer to be measured at three positions is measured respectively. The probe measurement value at the three positions is respectively the first position, the second position where the second non-magnetic theodolite is aligned with the second cubic face normal of the cubic mirror, and the third position where the first theodolite is aligned with the second cubic face normal of the cubic mirror; the first rotation added field value is calibrated based on the linear factor, orthogonality and zero bias of the Helmholtz coil to obtain the calibrated first rotation added field value, and the rotation matrix of the three positions is obtained based on the calibrated first rotation added field value and the probe measurement values ​​at the three positions; the first cubic face normal and the second cubic face normal of the cubic mirror in the sensor coordinate system are solved by the transformation matrix of the three positions, and the first cubic face normal and the first cubic face normal are obtained based on the first cubic face normal and the first cubic face normal. The orthogonality calibration result is determined by measuring the normals of two cubic aspects. The orthogonality calibration result includes the angle deviation between the normal of the first cubic aspect and the normal of the second cubic aspect, and the conversion matrix between the orthogonal matrix based on the magnetic axis and the mechanical axis. The method calibrates the Helmholtz coil to reduce the error of the applied known magnetic field. The method also uses two non-magnetic theodolites to establish a precise rectangular coordinate system, and uses a non-magnetic turntable, laser, and cubic mirror to improve the alignment accuracy of the mechanical axis, reduce experimental operation errors, and thus improve the accuracy of the conversion matrix between the vector magnetometer measurement value and the actual magnetic field measurement value. Based on this, the non-orthogonality of the magnetic axis and the mechanical axis is effectively corrected, and the overall measurement accuracy of the vector magnetometer is improved.

[0022] Please refer to Figure 1 , Figure 1The steps of a method for calibrating the orthogonality of a magnetic axis and a mechanical axis according to an embodiment of the present application are shown. The apparatus includes: a Helmholtz coil, a non-magnetic turntable, two non-magnetic theodolites, a reference cubic mirror, and an electronics box. The non-magnetic turntable is placed at the center of the Helmholtz coil, and the two non-magnetic theodolites establish a rectangular coordinate system for the Helmholtz coil. The two non-magnetic theodolites include a first non-magnetic theodolite and a second non-magnetic theodolite. like Figure 1 As shown, the calibration method includes the following steps S101-S106: S101, calibrating the Helmholtz coil, calculating the linear factor, orthogonality and zero bias of the Helmholtz coil; S102, placing the magnetometer to be tested on the non-magnetic turntable; wherein a reference cubic mirror is fixed to the top of the housing of the probe of the magnetometer to be tested, and the three cubic faces of the reference cubic mirror respectively represent the normal directions of the three mechanical axes; and connecting the probe of the magnetometer to be tested to an electronics box; S103, adjusting the two non-magnetic theodolites so that the normal directions of the first cubic face and the second cubic face of the cubic mirror are aligned with the two non-magnetic theodolites respectively and meet a preset alignment accuracy; setting the first position after alignment as the alignment of the normal directions of the first cubic face of the first non-magnetic theodolite and the cubic mirror; S104, inputting a first rotational applied field value into the Helmholtz coil, rotating the non-magnetic turntable, and measuring probe measurement values ​​of the magnetometer probe under test at three positions, respectively; the three positions being the first position, a second position where the second non-magnetic theodolite is aligned with the second cubic face of the cubic mirror in a normal direction, and a third position where the first theodolite is aligned with the second cubic face of the cubic mirror in a normal direction; S105, calibrating the first rotation added field value based on the linear factor, orthogonality, and zero bias of the Helmholtz coil to obtain a calibrated first rotation added field value, and obtaining a rotation matrix at three positions based on the calibrated first rotation added field value and probe measurement values ​​at three positions; S106. Solve the first cube face normal and the second cube face normal of the cubic mirror in the sensor coordinate system through the transformation matrix of the three positions, and determine the orthogonality calibration result based on the first cube face normal and the second cube face normal; the orthogonality calibration result includes: the angular deviation between the first cube face normal and the second cube face normal, and the transformation matrix between the orthogonal matrix based on the magnetic axis and the mechanical axis.

[0023] That is, the orthogonality calibration method of the magnetic axis and the mechanical axis described in the embodiment of the present application is to place the fluxgate magnetometer to be measured at the center of the Helmholtz field coil and apply a stable and uniform magnetic field; a cubic mirror is attached to the top of the magnetometer, and the cubic mirror is used as the mechanical axis reference. The relationship between the mechanical axis and the magnetic axis is determined by the rotation method, and the conversion relationship between the orthogonal matrix based on the magnetic axis and the mechanical axis can be obtained.

[0024] In step S101 , the Helmholtz coil is calibrated, and the linearity factor, orthogonality and zero bias of the Helmholtz coil are calculated.

[0025] The Helmholtz coil may also be referred to as a Helmholtz field coil or a Helmholtz coil mechanism.

[0026] Please refer to Figure 2 The calibrating of the Helmholtz coil and the calculation of the linear factor, orthogonality and zero bias of the Helmholtz coil include the following steps S201-S202: S201, placing a proton magnetometer at the center of the Helmholtz coil, and inputting a second rotating added field value into the Helmholtz coil system; the total field of the second rotating added field value is 50000 nT, and the vector direction is uniformly distributed on a sphere; S202: Collect the proton magnetometer data, calibrate the coil, and calculate the linear factor, orthogonality, and zero bias of the coil.

[0027] The proton magnetometer is an Overhauser proton magnetometer.

[0028] Calibrate the Helmholtz coil and calculate the linear factor of the coil , orthogonality and zero bias The calibrated coil field value can be approximated to the true geomagnetic field value in the coil coordinate system; through calibration, the coil can represent the current true geomagnetic field value and reduce the error of the applied known magnetic field.

[0029] Specifically, please refer to the following formula (5): ……(5); in, is the coil field value after calibration; is the linear factor of the coil; is the orthogonality of the coils and It is the zero bias of the coil and also the zero bias of the calibrated magnetometer.

[0030] In step S102, the magnetometer to be tested is placed on the non-magnetic turntable; wherein a reference cubic mirror is fixed to the top of the housing of the probe of the magnetometer to be tested, and the three cubic faces of the reference cubic mirror respectively represent the normal directions of the three mechanical axes; the probe of the magnetometer to be tested is connected to an electronics box.

[0031] Specifically, a non-magnetic turntable is placed at the center of the Helmholtz field coil, the reference cubic mirror is attached to the top of the magnetometer probe housing to be tested, the magnetometer probe to be tested and the electronics box are connected and placed on the non-magnetic turntable, the host is turned on and the device status is checked, and it is preheated for 60 minutes.

[0032] In step S103, the two non-magnetic theodolites are adjusted so that the first cubic face normal and the second cubic face normal of the cubic mirror are aligned with the two non-magnetic theodolites respectively and meet the preset alignment accuracy; the first position after alignment is set as the alignment of the first cubic face normal of the first non-magnetic theodolite and the cubic mirror.

[0033] The adjusting of the two non-magnetic theodolites so that the first cubic face normal and the second cubic face normal of the cubic mirror are respectively aligned with the two non-magnetic theodolites and meet the preset alignment accuracy includes: Laser is used to preliminarily align the normal direction of the first cubic face and the normal direction of the second cubic face of the cubic mirror with two non-magnetic theodolites respectively; The position of the non-magnetic turntable is fine-tuned until the alignment accuracy of the cubic mirror and the two non-magnetic theodolites meets the preset alignment accuracy; the preset alignment accuracy is 2 arc seconds.

[0034] Please refer to Figure 3 , arrange non-magnetic theodolites so that the two theodolites establish a rectangular coordinate system (such as Figure 3 Use laser to roughly align the two surface normals of the cubic mirror with the two theodolites, and then make fine adjustments until the alignment accuracy of the cubic mirror and the two theodolites is 2 arc seconds, so that the second theodolite is aligned with the surface normal of the first cubic mirror. The position at this time is recorded as the first position ( Figure 3 #1 in the figure); after the non-magnetic turntable rotates, it can be rotated to the second position ( Figure 3 #2 in the ) and the third position ( Figure 3 (#3 in the example).

[0035] In step S104, a first rotational field value is input to the Helmholtz coil, the non-magnetic turntable is rotated, and probe measurement values ​​of the probe of the magnetometer to be measured are measured at three positions respectively; the three positions are respectively the first position, the second position where the second non-magnetic theodolite is aligned normally with the second cubic face of the cubic mirror, and the third position where the first theodolite is aligned normally with the second cubic face of the cubic mirror.

[0036] Specifically, inputting a first rotating field value to the Helmholtz coil, rotating the non-magnetic turntable, and respectively measuring probe measurement values ​​of the probe of the magnetometer to be measured at three positions include: Input a first rotating field value to the Helmholtz coil system to obtain a probe measurement value of the magnetometer to be measured at a first position. ; rotating the non-magnetic turntable to move the cubic mirror to a second position, and fine-tuning the horizontal plane of the non-magnetic turntable to align the second non-magnetic theodolite with the normal of the second cubic face of the cubic mirror; Input a first rotating field value to the Helmholtz coil system to obtain a probe measurement value of the magnetometer to be measured at a second position. ; Rotating the non-magnetic turntable to move the cubic mirror to a third position, and fine-tuning the horizontal plane of the non-magnetic turntable to align the first non-magnetic theodolite with the normal of the second cubic face of the cubic mirror; Input a first rotating field value to the Helmholtz coil system to obtain a probe measurement value of the magnetometer to be measured at a second position. .

[0037] The first rotation added field value is the same as the second rotation added field value input when calibrating the coil, the total field is 50000 nT, and the vector direction is evenly distributed on a spherical surface.

[0038] In some embodiments, specifically, the rotating field value (the total field is 50000nT, and the vector direction is uniformly distributed on a sphere) is input to the Helmholtz coil system, and the vector magnetometer stores the measurement data to obtain the probe measurement value by calculation. To coil field value The transformation matrix R 1.

[0039] Rotate the non-magnetic turntable cubic surface to the second position (rotate around the optical axis of the theodolite), and fine-tune the horizontal plane of the non-magnetic turntable to align the theodolite 2 with the cubic surface 1 in the normal direction.

[0040] The rotating field value is input to the Helmholtz coil system (the total field is 50000nT, and the vector direction is evenly distributed on a sphere). The vector magnetometer stores the measurement data and obtains the probe measurement value through calculation. To coil field value The transformation matrix R 2.

[0041] Rotate the non-magnetic turntable cube to the third position, and fine-tune the horizontal plane of the non-magnetic turntable to align the first theodolite with the normal of the second cube.

[0042] The rotating field value is input to the Helmholtz coil system (the total field is 50000nT, and the vector direction is evenly distributed on a sphere). The vector magnetometer stores the measurement data and obtains the probe measurement value through calculation. To coil field value The transformation matrix R 3.

[0043] The host is shut down, the test is completed, and the stored data is sorted and processed.

[0044] In step S105, the first rotation added field value is calibrated based on the linear factor, orthogonality and zero bias of the Helmholtz coil to obtain a calibrated first rotation added field value, and the rotation matrix of the three positions is obtained based on the calibrated first rotation added field value and the probe measurement values ​​at the three positions.

[0045] In some embodiments, calibrating the first rotating added field value based on the linear factor, orthogonality, and zero bias of the Helmholtz coil to obtain the calibrated first rotating added field value includes: The calibrated first rotation plus field value is calculated based on the following formula (1): ... (1); Among them, the Characterizing the first rotation-added field value of the input; Characterizes the calibrated first rotation field value, Characterize the linear factor, Characterize orthogonality; Characterize zero bias.

[0046] The rotation matrix of the three positions is obtained based on the calibrated first rotation field value and the probe measurement values ​​at the three positions, including: The first rotation matrix of the probe measurement value at the first position and the calibrated first rotation plus field value is calculated by the following formula (2): R 1; ... (2); Among them, the a probe measurement representing a first position; R 1The first rotation matrix.

[0047] The second rotation matrix of the probe measurement value at the second position and the calibrated first rotation plus field value is calculated by the following formula (3): R 2; ... (3); in, a probe measurement representing a second position; R 2 The second rotation matrix.

[0048] The third rotation matrix of the probe measurement value at the third position and the calibrated first rotation plus field value is calculated by the following formula (4): R 3; ……(4); in, a probe measurement representing a third position; R 3The third rotation matrix.

[0049] In step S106, the first cube face normal and the second cube face normal of the cubic mirror in the sensor coordinate system are solved by the transformation matrix of the three positions, and the orthogonality calibration result is determined based on the first cube face normal and the second cube face normal.

[0050] Please refer to Figure 4 , solving the first cube face normal and the second cube face normal of the cubic mirror in the sensor coordinate system through the transformation matrix of the three positions, and determining the orthogonality calibration result based on the first cube face normal and the second cube face normal, including the following steps S401-S405: S401, calculating a fourth rotation matrix of the magnetometer to be measured from a first position to a second position, and calculating an eigenvector of the fourth rotation matrix; the eigenvector of the fourth rotation matrix is ​​a first cubic face normal of the cubic mirror in a sensor coordinate system; S402, calculating the direction of the optical rotation axis in the coil coordinate system based on the fourth rotation matrix and the first cube face normal; S403, calculating a second cubic face normal of the cubic mirror in the sensor coordinate system based on a third rotation matrix corresponding to the third position and the direction of the optical rotation axis; S404, calculating the angle deviation between the normal direction of the first cube face and the normal direction of the second cube face; S405 : Determine a target conversion matrix between the magnetic field of the mechanical coordinate system of the cubic mirror and the magnetic field of the sensor coordinate system based on the first cube face normal and the second cube face normal, wherein the target conversion matrix represents a conversion matrix between an orthogonal matrix based on a magnetic axis and a mechanical axis.

[0051] The mechanical coordinate system magnetic field of the cubic mirror is a coordinate system magnetic field established based on the cubic mirror.

[0052] The principle of the orthogonality calibration method of the magnetic axis and the mechanical axis described in the embodiment of the present application is analyzed below.

[0053] The conversion matrix between the vector magnetometer measurements and the true magnetic field measurements is calculated as follows: The relationship between the vector magnetometer measurement value and the true value of the magnetic field can be expressed as the following formula (6) and formula (7): ... (6); ……(7); Among them, the calibration matrix is a 3×3 matrix, b is the zero bias of the magnetometer, also known as offset, which can be calculated by the magnetometer calibration method; is the linear factor of the coil; is the orthogonality of the coils; is the vector magnetometer measurement, is the true magnetic field measurement value.

[0054] Since the coil field value It can be regarded as the real magnetic field measurement value, so the vector magnetometer measurement value (First position) and coil field value The transformation matrix is ​​as follows (8): ……(8); in, .

[0055] Vector magnetometer measurements (Second position) and coil field value The transformation matrix is ​​as follows (9): ... (9); in, .

[0056] Vector magnetometer measurements (Position #3) and coil field value The transformation matrix is ​​as follows (10): …… (10) in, .

[0057] The conversion matrix between the magnetic sensitive axis and the mechanical axis of the cubic mirror is calculated as follows: First, we can get the following formulas (11) and (12); ……(11); = … (12); in is the transformation matrix of the magnetometer from the first position to the second position, The eigenvector of It is defined as the following formula (13); … (13); Since the rotation from position #1 to position #2 is around the optical axis of the automatic alignment of theodolite 1, The direction is the axial direction of the first non-magnetic theodolite automatic alignment in the sensor coordinate system, that is, the normal direction of the first cubic face, converted to the Helmholtz coil coordinate system Since the rotation vector has three eigenvalues: , That is The rotation angle from position 1 to position 2.

[0058] At the third position, the normal direction of the second cubic face in the sensor coordinate system can be calculated by the following formula (14): … (14); The angle between the normal to the first cubic face and the normal to the second cubic face is given by the following formula (15): ……(15); Therefore, an optical reference axis can be established and The orthogonal coordinate system of the cubic mirror mechanical coordinate system has three coordinate axes: , , , the magnetic field in this coordinate system Magnetic field in the magnetic sensitive axis coordinate system The transformation matrix is ​​as follows (16): … (16); in

[0059]

[0060] 。

[0061] Based on this, after calculating the three rotation matrices corresponding to the three positions, the first cube face normal and the second cube face normal of the cubic mirror in the sensor coordinate system are solved by the transformation matrices of the three positions, and the orthogonality calibration result is determined based on the first cube face normal and the second cube face normal, as follows: (1) Calculate the rotation matrix of the magnetometer to be tested from the first position to the second position ; (2) Calculation eigenvector of , that is, the normal direction of the first cubic face in the sensor coordinate system, so that ; Calculate the direction of the optical rotation axis in the coil coordinate system , The eigenvalue of , for The rotation angle from position 1 to position 2; (3) Calculate the normal direction of the cubic face 2 in the sensor coordinate system The angle between the normals of two cube faces for: ； (4) Therefore, an orthogonal coordinate system based on the mechanical axis of the cubic mirror can be established, and the coordinate axes in the three directions are , , , the magnetic field in this coordinate system is: ； in ， ， 。

[0062] The following is a test example of a method for calibrating the orthogonality of the magnetic axis and mechanical axis of a magnetometer under test.

[0063] Please refer to Figure 5 , Figure 5 FIG. 1 shows a schematic diagram of the magnetic field measurement results of the Helmholtz coil calibration according to an embodiment of the present application; in the Helmholtz coil calibration process, as shown in FIG. Figure 5 As shown, from top to bottom are the three components of the coil applied field and the scalar magnetic field measurement values ​​of the proton magnetometer.

[0064] Please refer to Figure 6 , Figure 6 An example diagram of the Helmholtz coil calibration according to an embodiment of the present application is shown; Figure 6 It is a grouped scatter plot composed of multiple sub-graphs, such as Figure 6 As shown, from top to bottom are the three components of the magnetic field x, y, and z of the coil ( Figure 6 The child Figure 1 ,son Figure 2 Kazuko Figure 3 Total field (sub Figure 4 , where the blue dots are uncalibrated, the green dots are Overhauser measurements, and the red dots are calibrated total field values); Total field residual (sub Figure 5 ).

[0065] The coil calibration parameters are shown in Table 1: Table 1 Sensitivities, in nT / EU:1.00149391.00058940.99974595 offset, in nT:-14.525832-1.87698650.58799202 Misalignment Angle (xy), (xz), (yz), in deg: 0.0123600380.18785198-0.046998853 The following is an example of calculating the transformation matrix between the magnetic sensitive axis and the mechanical axis of the cubic mirror.

[0066] Please refer to Figure 7 , Figure 7 An example of calculating the conversion matrix between the measured value of the magnetometer to be measured and the real magnetic field measurement value is shown; Figure 7 As shown, from top to bottom are the three components of the measured magnetic field x, y, and z ( Figure 7 The child Figure 1 ,son Figure 2 Kazuko Figure 3 Total field ( Figure 7 The child Figure 4 , where the blue dots are uncalibrated, the green dots are the magnetic field scalar values ​​after coil calibration, and the red dots are the total field values ​​after vector magnetometer calibration); total field residual ( Figure 7 The child Figure 5 ).

[0067] By using the orthogonality calibration method mentioned in the embodiment of the present application, the three transformation matrices at the first position, the second position, and the third position relative to the coil coordinate system are calculated. 、 、 , the specific calculation results are:

[0068]

[0069] , satisfy = , in, 、 are the measurement values ​​of the sensor coordinate system at three positions, The magnetic field measurement value is obtained in the coil coordinate system.

[0070] , eigenvector of , that is, the normal direction of the first cubic face in the sensor coordinate system (theodolite automatically aligns to the axis) is: ; Convert the optical axis direction to the coil coordinate system: ; The eigenvalue of , which can be calculated =90.016°, which is the rotation angle from position 1 to position 2, and the rotation error is 0.016°.

[0071] Normal direction of the cubic face 2 in the sensor coordinate system ; To evaluate the error in the cube face normal direction, the angle between the two cube face normals was calculated.

[0072] =89.968°; Therefore, the angular deviation between the normal of the first cubic face and the normal of the second cubic face is approximately 0.032°, and the error sources are mainly the alignment error of the theodolite and the error of the calibration algorithm.

[0073] The magnetic field in the mechanical coordinate system of the cubic mirror can be established Magnetic field in the magnetic sensitive axis coordinate system The conversion relationship: ； Magnetic field in the mechanical coordinate system of the cubic mirror Magnetic field in the magnetic sensitive axis coordinate system The transformation matrix for: ; Please refer to Figure 8 , Figure 8 The coordinate system diagram of the sensor coordinate system and the cubic mirror coordinate system is shown. In order to make the three-axis direction consistent with the sensor coordinate system, further conversion can be obtained: ; in, It is the transformation matrix between the sensor coordinate system and the cubic mirror coordinate system with consistent three-axis directions.

[0074] That is, the conversion matrix between the orthogonal matrix based on the magnetic axis and the mechanical axis , the three components of the magnetic field in the magnetic sensitive axis coordinate system Three components of the magnetic field in the mechanical coordinate system of the cubic mirror The conversion relationship is ; .

[0075] Based on the same inventive concept, an embodiment of the present application also provides an orthogonality calibration device for the magnetic axis and the mechanical axis corresponding to the orthogonality calibration method for the magnetic axis and the mechanical axis. Since the principle of solving the problem by the device in the embodiment of the present application is similar to the orthogonality calibration method for the magnetic axis and the mechanical axis in the above-mentioned embodiment of the present application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0076] In some embodiments, a device for calibrating the orthogonality of a magnetic axis and a mechanical axis is further provided, the device comprising: a Helmholtz coil, a non-magnetic turntable, two non-magnetic theodolites, a reference cubic mirror, an electronics box, and a processor, wherein the non-magnetic turntable is placed at the center of the Helmholtz coil, and the two non-magnetic theodolites establish a rectangular coordinate system for the Helmholtz coil; the two non-magnetic theodolites include a first non-magnetic theodolite and a second non-magnetic theodolite; During calibration, the magnetometer to be tested is placed on the non-magnetic turntable; a reference cubic mirror is fixed to the top of the housing of the probe of the magnetometer to be tested, and the three cubic faces of the reference cubic mirror represent the normal directions of the three mechanical axes respectively; the probe of the magnetometer to be tested is connected to an electronics box, and the electronics box is connected to the processor; Adjusting the two non-magnetic theodolites so that the normal directions of the first cubic face and the second cubic face of the cubic mirror are aligned with the two non-magnetic theodolites respectively and meet a preset alignment accuracy; setting a first position after alignment as the alignment of the normal directions of the first cubic face of the first non-magnetic theodolite and the cubic mirror; Inputting a first rotational applied field value to the Helmholtz coil, rotating the non-magnetic turntable, and measuring probe measurement values ​​of a probe of the magnetometer to be measured at three positions, respectively; the three positions are the first position, a second position in which the second non-magnetic theodolite is aligned with the second cubic face of the cubic mirror in a normal direction, and a third position in which the first theodolite is aligned with the second cubic face of the cubic mirror in a normal direction; The processor is configured to calibrate the first rotation added field value based on the calibrated linear factor, orthogonality, and zero bias of the Helmholtz coil to obtain a calibrated first rotation added field value, and obtain a rotation matrix at the three positions based on the calibrated first rotation added field value and probe measurement values ​​at the three positions; solve the first cubic face normal and the second cubic face normal of the cubic mirror in the sensor coordinate system through the transformation matrix at the three positions, and determine an orthogonality calibration result based on the first cubic face normal and the second cubic face normal; the orthogonality calibration result includes: an angular deviation between the first cubic face normal and the second cubic face normal, and a magnetic field of a magnetic axis coordinate system and a magnetic field of a mechanical axis coordinate system.

[0077] Based on the same inventive concept, an embodiment of the present application also provides an electronic device corresponding to the method for calibrating the orthogonality of the magnetic axis and the mechanical axis. Since the principle of solving the problem by the electronic device in the embodiment of the present application is similar to the method for calibrating the orthogonality of the magnetic axis and the mechanical axis in the above-mentioned embodiment of the present application, the implementation of the electronic device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0078] Please refer to Figure 9 , Figure 9A schematic diagram of the structure of an electronic device described in an embodiment of the present application is shown; the electronic device 900 includes: a processor 901, a memory 902, and a bus. The memory 902 stores machine-readable instructions executable by the processor 901. When the electronic device 900 is running, the processor 901 communicates with the memory 902 via the bus. When the machine-readable instructions are executed by the processor 901, the steps of any one of the methods for calibrating the orthogonality of the magnetic axis and the mechanical axis are performed, specifically as follows: The first rotation added field value is calibrated based on the calibrated linear factor, orthogonality and zero bias of the Helmholtz coil to obtain a calibrated first rotation added field value, and the rotation matrix of the three positions is obtained based on the calibrated first rotation added field value and the probe measurement values ​​at the three positions; the first cubic face normal and the second cubic face normal of the cubic mirror in the sensor coordinate system are solved by the transformation matrix of the three positions, and the orthogonality calibration result is determined based on the first cubic face normal and the second cubic face normal; the orthogonality calibration result includes: the angular deviation between the first cubic face normal and the second cubic face normal, the magnetic field of the magnetic axis coordinate system and the magnetic field of the mechanical axis coordinate system.

[0079] That is, the processor of the electronic device executes the software portion (ie, the calculation portion) of the method for calibrating the orthogonality of the magnetic axis and the mechanical axis.

[0080] Based on the same inventive concept, the embodiment of the present application also provides a computer-readable storage medium corresponding to the method for calibrating the orthogonality of the magnetic axis and the mechanical axis. Since the principle of solving the problem by the computer-readable storage medium in the embodiment of the present application is similar to the method for calibrating the orthogonality of the magnetic axis and the mechanical axis in the above-mentioned embodiment of the present application, the implementation of the computer-readable storage medium can refer to the implementation of the method, and the repeated parts will not be repeated.

[0081] A computer-readable storage medium stores a computer program, which is executed by a processor to execute the steps of the method for calibrating the orthogonality of the magnetic axis and the mechanical axis, specifically as follows: The first rotation added field value is calibrated based on the calibrated linear factor, orthogonality and zero bias of the Helmholtz coil to obtain a calibrated first rotation added field value, and the rotation matrix of the three positions is obtained based on the calibrated first rotation added field value and the probe measurement values ​​at the three positions; the first cubic face normal and the second cubic face normal of the cubic mirror in the sensor coordinate system are solved by the transformation matrix of the three positions, and the orthogonality calibration result is determined based on the first cubic face normal and the second cubic face normal; the orthogonality calibration result includes: the angular deviation between the first cubic face normal and the second cubic face normal, the magnetic field of the magnetic axis coordinate system and the magnetic field of the mechanical axis coordinate system.

[0082] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the system and device described above can refer to the corresponding process in the method embodiment, and will not be repeated in this application. In the several embodiments provided in this application, it should be understood that the disclosed system, device and method can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the modules is only a logical function division. There may be other division methods in actual implementation. For example, multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, indirect coupling or communication connection of devices or modules, which can be electrical, mechanical or other forms.

[0083] The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical units, that is, they may be located in one place or distributed across multiple network elements. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0084] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0085] If the functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this application, or the portion that contributes to the prior art, or the portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, platform server, or network device, etc.) to execute all or part of the steps of the methods described in various embodiments of this application. The aforementioned storage media include various media that can store program code, such as USB flash drives, mobile hard drives, ROM, RAM, magnetic disks, or optical disks.

[0086] The above are only specific embodiments of the present application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A method for calibrating the orthogonality of a magnetic axis and a mechanical axis, characterized in that: An orthogonality calibration device for magnetic and mechanical axes, comprising: a Helmholtz coil, a non-magnetic turntable, two non-magnetic theodolites, a reference cubic mirror, and an electronics box. The non-magnetic turntable is placed at the center of the Helmholtz coil, and the two non-magnetic theodolites establish a rectangular coordinate system for the Helmholtz coil. The two non-magnetic theodolites include a first non-magnetic theodolite and a second non-magnetic theodolite. The calibration method comprises the following steps: Calibrate the Helmholtz coil and calculate the linearity factor, orthogonality and zero bias of the Helmholtz coil; The magnetometer to be tested is placed on the non-magnetic turntable; wherein a reference cubic mirror is fixed to the top of the housing of the probe of the magnetometer to be tested, and the three cubic faces of the reference cubic mirror represent the normal directions of the three mechanical axes respectively; the probe of the magnetometer to be tested is connected to an electronics box; Adjusting the two non-magnetic theodolites so that the normal directions of the first cubic face and the second cubic face of the cubic mirror are aligned with the two non-magnetic theodolites respectively and meet a preset alignment accuracy; setting a first position after alignment as the alignment of the normal directions of the first cubic face of the first non-magnetic theodolite and the cubic mirror; Inputting a first rotational applied field value to the Helmholtz coil, rotating the non-magnetic turntable, and measuring probe measurement values ​​of a probe of the magnetometer to be measured at three positions, respectively; the three positions are the first position, a second position in which the second non-magnetic theodolite is aligned with the second cubic face of the cubic mirror in a normal direction, and a third position in which the first theodolite is aligned with the second cubic face of the cubic mirror in a normal direction; Calibrate the first rotation added field value based on the linear factor, orthogonality, and zero bias of the Helmholtz coil to obtain a calibrated first rotation added field value, and obtain rotation matrices at three positions based on the calibrated first rotation added field value and probe measurement values ​​at three positions; The first cube face normal and the second cube face normal of the cubic mirror in the sensor coordinate system are solved by the conversion matrix of the three positions, and the orthogonality calibration result is determined based on the first cube face normal and the second cube face normal; the orthogonality calibration result includes: the angular deviation between the first cube face normal and the second cube face normal, and the conversion matrix between the orthogonal matrix based on the magnetic axis and the mechanical axis.

2. The method for calibrating the orthogonality of the magnetic axis and the mechanical axis according to claim 1, wherein: The calibrating of the Helmholtz coil and calculating the linearity factor, orthogonality and zero bias of the Helmholtz coil include: Placing a proton magnetometer at the center of the Helmholtz coil and inputting a second rotating added field value into the Helmholtz coil system; the total field of the second rotating added field value is 50,000 nT, and the vector direction is uniformly distributed on a spherical surface; The proton magnetometer data is collected, the coil is calibrated, and the linearity factor, orthogonality and zero bias of the coil are calculated.

3. The method for calibrating the orthogonality of the magnetic axis and the mechanical axis according to claim 1, wherein: The adjusting of the two non-magnetic theodolites so that the first cubic face normal and the second cubic face normal of the cubic mirror are respectively aligned with the two non-magnetic theodolites and meet the preset alignment accuracy includes: Laser is used to preliminarily align the normal direction of the first cubic face and the normal direction of the second cubic face of the cubic mirror with two non-magnetic theodolites respectively; The position of the non-magnetic turntable is fine-tuned until the alignment accuracy of the cubic mirror and the two non-magnetic theodolites meets the preset alignment accuracy; the preset alignment accuracy is 2 arc seconds.

4. The method for calibrating the orthogonality of a magnetic axis and a mechanical axis according to claim 1, wherein: The step of inputting a first rotating field value to the Helmholtz coil, rotating the non-magnetic turntable, and respectively measuring probe measurement values ​​of the magnetometer to be tested at three positions includes: Input a first rotating field value to the Helmholtz coil system to obtain a probe measurement value of the magnetometer to be measured at a first position. ; rotating the non-magnetic turntable to move the cubic mirror to a second position, and fine-tuning the horizontal plane of the non-magnetic turntable to align the second non-magnetic theodolite with the normal of the second cubic face of the cubic mirror; Input a first rotating field value to the Helmholtz coil system to obtain a probe measurement value of the magnetometer to be measured at a second position. ; Rotating the non-magnetic turntable to move the cubic mirror to a third position, and fine-tuning the horizontal plane of the non-magnetic turntable to align the first non-magnetic theodolite with the normal of the second cubic face of the cubic mirror; Input a first rotating field value to the Helmholtz coil system to obtain a probe measurement value of the magnetometer to be measured at a second position. .

5. The method for calibrating the orthogonality of a magnetic axis and a mechanical axis according to claim 1, wherein: The step of calibrating the first rotating added field value based on the linear factor, orthogonality, and zero bias of the Helmholtz coil to obtain the calibrated first rotating added field value includes: The calibrated first rotation plus field value is calculated based on the following formula (1): ... (1); Among them, the Characterizing the first rotation-added field value of the input; Characterizes the calibrated first rotation field value, Characterize the linear factor, Characterize orthogonality; Characterize zero bias.

6. The method for calibrating the orthogonality of the magnetic axis and the mechanical axis according to claim 5, wherein: The rotation matrix of the three positions is obtained based on the calibrated first rotation field value and the probe measurement values ​​at the three positions, including: The first rotation matrix of the probe measurement value at the first position and the calibrated first rotation plus field value is calculated by the following formula (2): R 1; ……（2）； Among them, the a probe measurement representing a first position; R 1 first rotation matrix; The second rotation matrix of the probe measurement value at the second position and the calibrated first rotation plus field value is calculated by the following formula (3): R 2; ……（3）； in, a probe measurement representing a second position; R 2 second rotation matrix; The third rotation matrix of the probe measurement value at the third position and the calibrated first rotation plus field value is calculated by the following formula (4): R 3; ……（4）； in, a probe measurement representing a third position; R 3The third rotation matrix.

7. The method for calibrating the orthogonality of the magnetic axis and the mechanical axis according to claim 6, wherein: Solving the first cube face normal and the second cube face normal of the cubic mirror in the sensor coordinate system through the transformation matrix of the three positions, and determining the orthogonality calibration result based on the first cube face normal and the second cube face normal, including: Calculating a fourth rotation matrix of the magnetometer to be measured from the first position to the second position, and calculating an eigenvector of the fourth rotation matrix; the eigenvector of the fourth rotation matrix is ​​a first cubic face normal of the cubic mirror in the sensor coordinate system; Calculating the direction of the optical rotation axis in the coil coordinate system based on the fourth rotation matrix and the first cube face normal; Calculating a second cubic face normal of the cubic mirror in the sensor coordinate system based on a third rotation matrix corresponding to the third position and the direction of the optical rotation axis; Calculate the angle deviation between the normal direction of the first cubic face and the normal direction of the second cubic face; Based on the first and second cube face normals, a target conversion matrix between the magnetic field of the cubic mirror mechanical coordinate system and the magnetic field of the sensor coordinate system is determined, wherein the target conversion matrix represents a conversion matrix between an orthogonal matrix based on a magnetic axis and a mechanical axis.

8. A device for calibrating the orthogonality of a magnetic axis and a mechanical axis, characterized in that: The device includes: a Helmholtz coil, a non-magnetic turntable, two non-magnetic theodolites, a reference cubic mirror, an electronics box, and a processor. The non-magnetic turntable is placed at the center of the Helmholtz coil, and the two non-magnetic theodolites establish a rectangular coordinate system for the Helmholtz coil. The two non-magnetic theodolites include a first non-magnetic theodolite and a second non-magnetic theodolite. During calibration, the magnetometer to be tested is placed on the non-magnetic turntable; a reference cubic mirror is fixed to the top of the housing of the probe of the magnetometer to be tested, and the three cubic faces of the reference cubic mirror represent the normal directions of the three mechanical axes respectively; the probe of the magnetometer to be tested is connected to an electronics box, and the electronics box is connected to the processor; Adjusting the two non-magnetic theodolites so that the normal directions of the first cubic face and the second cubic face of the cubic mirror are aligned with the two non-magnetic theodolites respectively and meet a preset alignment accuracy; setting a first position after alignment as the alignment of the normal directions of the first cubic face of the first non-magnetic theodolite and the cubic mirror; Inputting a first rotational applied field value to the Helmholtz coil, rotating the non-magnetic turntable, and measuring probe measurement values ​​of a probe of the magnetometer to be measured at three positions, respectively; the three positions are the first position, a second position in which the second non-magnetic theodolite is aligned with the second cubic face of the cubic mirror in a normal direction, and a third position in which the first theodolite is aligned with the second cubic face of the cubic mirror in a normal direction; The processor is configured to calibrate the first rotation added field value based on the calibrated linear factor, orthogonality, and zero bias of the Helmholtz coil to obtain a calibrated first rotation added field value, and obtain a rotation matrix at the three positions based on the calibrated first rotation added field value and probe measurement values ​​at the three positions; solve the first cubic face normal and the second cubic face normal of the cubic mirror in the sensor coordinate system through the transformation matrix at the three positions, and determine an orthogonality calibration result based on the first cubic face normal and the second cubic face normal; the orthogonality calibration result includes: an angular deviation between the first cubic face normal and the second cubic face normal, and a magnetic field of a magnetic axis coordinate system and a magnetic field of a mechanical axis coordinate system.

9. An electronic device, characterized in that: include: A processor, a memory, and a bus, wherein the memory stores machine-readable instructions executable by the processor. When the electronic device is running, the processor and the memory communicate via the bus. When the machine-readable instructions are executed by the processor, the steps of the method for calibrating the orthogonality of the magnetic axis and the mechanical axis as described in any one of claims 1 to 7 are performed.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, which, when executed by a processor, executes the steps of the method for calibrating the orthogonality of a magnetic axis and a mechanical axis according to any one of claims 1 to 7.

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