Magnetic field control system and method

Abstract

This invention provides a magnetic field control system and method. The system includes a coil, a magnetic field sensor, a position sensor, and a controller. The position sensor, fixed within the coil, acquires the coil's position signal and transmits it to the controller. The position signal includes position and direction information. The magnetic field sensor, also fixed within the coil, acquires the coil's magnetic field signal and transmits it to the controller. The controller, based on the received position and magnetic field signals, determines the magnetic field of a target area and adjusts the coil current distribution accordingly to achieve magnetic field control. This invention transmits information from the position and magnetic field sensors to the controller in real time. By using the position signal and the target area's position information, the relationship between each current segment of the coil and the magnetic field at a characteristic point in the target area is determined. This, combined with the magnetic field signal, determines the magnetic field of the target area, and then the coil current is adjusted based on the target area's magnetic field to achieve magnetic field control.

Description

Technical Field

[0001] This invention relates to the field of magnetic field control technology, and in particular to a magnetic field control system and method. Background Technology

[0002] With the development of technology, magnetic fields are everywhere in our lives; televisions, telephones, high-voltage power lines, and many other sources generate them. However, different magnetic fields have different effects. Some magnetic fields are convenient for us; for example, the Earth's magnetic field allows us to use a compass to determine direction. But other magnetic fields bring electromagnetic noise, such as interference signals. The measures we need to take for different magnetic fields will vary. Sometimes we need to amplify the magnetic field signal, for example, amplifying some signals makes them easier to measure and analyze. More often, we need to cancel or even shield some magnetic field signals.

[0003] In the medical field, it is necessary to shield external magnetic fields in order to precisely measure the weak magnetic fields generated by parts of the human body such as the heart and brain, thereby diagnosing the health status of the corresponding parts or studying their working methods.

[0004] In the chip industry, it is necessary to shield external magnetic fields and internal magnetic fields of equipment to reduce the influence of magnetic fields during the movement of electron beams, thereby increasing accuracy.

[0005] In the defense industry, it is necessary to shield noise and magnetic fields in order to identify and track the magnetic fields of specific objects such as submarines, landmines, and abandoned shells.

[0006] Currently used magnetic field control methods include passive and active magnetic shielding. Passive magnetic shielding mainly uses high-permeability materials to construct a closed cavity to enclose the protected object. By controlling the permeability of the material used to build the shielding cavity, the higher the permeability and the thicker the cavity wall, the more significant the shielding effect. However, the shielding mass is large, the weight is heavy, and the direction of the shielding magnetic field is optically opaque.

[0007] Typical active magnetic shielding systems can only generate 0th or 1st order spatial magnetic fields with a few degrees of freedom, making it difficult to effectively shield magnetic fields with complex spatial distributions. Furthermore, they are often fixed-shape systems, making it difficult to adapt to diverse shielding requirements. Summary of the Invention

[0008] This invention provides a magnetic field control system and method to solve the defects of optical opacity in the direction of shielding magnetic fields in the prior art, to counteract changes in magnetic fields, and to achieve real-time control of magnetic fields.

[0009] This invention provides a magnetic field control system, including a coil, a magnetic field sensor, a position sensor, and a controller, wherein: the position sensor is fixed in the coil and is used to acquire the position signal of the coil and transmit the position signal to the controller, the position signal including position information and direction information; the magnetic field sensor is fixed in the coil and is used to acquire the magnetic field signal of the coil and transmit the magnetic field signal to the controller; the controller, based on the received position signal and magnetic field signal, obtains the magnetic field of a target area, and adjusts the coil current distribution according to the magnetic field of the target area to achieve magnetic field control.

[0010] According to a magnetic field control system provided by the present invention, obtaining the magnetic field of a target region based on received position signals and magnetic field signals includes: obtaining coil attitude information based on the position signals, and obtaining coil magnetic field information based on the magnetic field signals; obtaining the relationship between the magnetic field of each current segment of the coil and the characteristic magnetic field of the target region, and obtaining the position magnetic field relationship between each current segment and the magnetic field sensor, based on the coil attitude information and the coil magnetic field information, combined with the current information of each current segment of the coil and the pre-acquired position information of the target region, using Biot-Savart's law; obtaining the magnetic field of the target region based on the characteristic magnetic field relationship and the position magnetic field relationship, combined with the current of each current segment of the coil.

[0011] According to a magnetic field control system provided by the present invention, obtaining the magnetic field relationship between each current segment of the coil and the feature point of the target region, and obtaining the position magnetic field relationship between each current segment and the magnetic field sensor, includes: selecting feature points from the target region based on pre-acquired position information of the target region to obtain feature point position information; obtaining position information of each current segment based on the coil attitude information and the pre-acquired position relationship of the position sensor relative to each current segment of the coil; and obtaining the magnetic field relationship between each current segment and the feature point of the target region, and the position magnetic field relationship between each current segment and the magnetic field sensor, using Biot-Savart's law, based on the feature point position information, the position information of each current segment, the current information of each current segment of the coil, and the coil magnetic field information.

[0012] According to a magnetic field control system provided by the present invention, the controller is further configured to: obtain coil magnetic field information based on the magnetic field signal when there is no current in the coil; and estimate the magnetic field distribution of the target area based on the coil magnetic field information to obtain the magnetic field of the target area.

[0013] According to a magnetic field control system provided by the present invention, the estimation of the magnetic field distribution of the target area based on the magnetic field signal includes: performing a Taylor expansion of the magnetic field signal according to spatial coordinates in a Cartesian coordinate system or a spherical coordinate system to obtain a Taylor expansion result; removing higher-order parameters in the Taylor expansion result based on a preset threshold, and fitting the Taylor expansion result after removing higher-order parameters.

[0014] According to a magnetic field control system provided by the present invention, adjusting the coil current according to the magnetic field of the target region includes: determining the coil current at the next moment according to the magnetic field of the target region; and adjusting the current of the coil according to the coil current at the next moment.

[0015] According to a magnetic field control system provided by the present invention, the coil includes a flexible cylindrical surface, a three-dimensional conductor grid, and a controllable resistor group, wherein: the three-dimensional conductor grid is formed by connecting conductive components through preset nodes; the flexible cylindrical surface covers the three-dimensional conductor grid; the controllable resistor group includes multiple controllable resistors, and the multiple controllable resistors are connected in parallel, the controllable resistor group is connected in parallel in the three-dimensional conductor grid, and the controllable resistor group is controlled by the controller.

[0016] According to a magnetic field control system provided by the present invention, the material of the flexible cylindrical surface includes at least one selected from polyurethane, polymethyl methacrylate and polyimide.

[0017] According to a magnetic field control system provided by the present invention, the magnetic field sensor includes at least one of a magnetoresistive sensor, a fluxgate sensor, an optical pump sensor, a magneto-inductor, and a magnetocalor; wherein the magnetoresistive sensor includes at least one of a giant magnetoresistive (GMR), anisotropic magnetoresistive (AMR), tunneling magnetoresistive (TMR), and Hall effect sensor.

[0018] The present invention also provides a magnetic field control method, applying any of the magnetic field control systems described above, comprising: receiving a position signal sent by a position sensor, the position signal including position information and direction information, and receiving a magnetic field signal sent by a magnetic field sensor; obtaining a target area magnetic field based on the received position signal and magnetic field signal, and adjusting the coil current distribution according to the target area magnetic field to achieve magnetic field control.

[0019] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of any of the above-described magnetic field control methods.

[0020] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any of the above-described magnetic field control methods.

[0021] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of any of the above-described magnetic field control methods.

[0022] The magnetic field control system and method provided by this invention transmit information from a position sensor and a magnetic field sensor to a controller in real time. By using the position signal from the position sensor and the position information of the target area, the magnetic field relationship between each current segment of the coil and the characteristic point magnetic field of the target area is determined. Combined with the magnetic field signal from the magnetic field sensor, the magnetic field of the target area is determined, and then the current required by the coil at the next moment is obtained. The controller then changes the coil current to control the magnetic field of the target area within the required range, thereby achieving magnetic field control. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the magnetic field control system provided by the present invention;

[0025] Figure 2 This is one of the schematic diagrams of the coil provided by the present invention;

[0026] Figure 3 This is the second schematic diagram of the coil provided by the present invention;

[0027] Figure 4 This is a flowchart illustrating the magnetic field control method provided by the present invention;

[0028] Figure 5 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0030] Figures 1-2 A magnetic field control system is shown, including a coil, a magnetic field sensor, a position sensor, and a controller, wherein:

[0031] The position sensor is fixed in the coil to acquire the position signal of the coil and transmit the position signal to the controller. The position signal includes position information and direction information.

[0032] A magnetic field sensor is fixed in a coil to acquire the magnetic field signal of the coil and transmit the magnetic field signal to the controller;

[0033] The controller obtains the magnetic field of the target area based on the received position signal and magnetic field signal, and adjusts the coil current distribution according to the magnetic field of the target area to achieve magnetic field control.

[0034] It should be added that the coil current distribution is used to characterize the current distribution on one surface of the coil, not the overall current magnitude of the coil.

[0035] In this embodiment, reference Figures 2-3 The coil includes a flexible cylindrical surface, a three-dimensional conductor grid, and a controllable resistor group, wherein: the three-dimensional conductor grid is formed by connecting conductive components through preset nodes; the flexible cylindrical surface covers the three-dimensional conductor grid; the controllable resistor group includes multiple controllable resistors, which are connected in parallel, and the controllable resistor group is connected in parallel in the three-dimensional conductor grid, and the controllable resistor group is controlled by a controller.

[0036] In one alternative embodiment, the material of the flexible cylindrical surface includes at least one of polyurethane, polymethyl methacrylate, and polyimide.

[0037] In one optional embodiment, the conductive component can be made of a conductive material, such as at least one of copper, gold, silver, and aluminum. When copper wire is selected as the conductive component, it is welded at preset nodes to form a two-dimensional three-dimensional conductor grid. Multiple layers of the two-dimensional three-dimensional conductor grid are then connected through preset nodes to obtain a three-dimensional conductor grid. It should be noted that copper wire provides good conductivity when used as the conductive component. Furthermore, the number of layers in the two-dimensional three-dimensional conductor grid can be determined according to the actual shape and usage requirements of the coil; no further limitations are imposed here.

[0038] In one optional embodiment, the controllable resistor includes at least one of a transistor, a field-effect transistor, a varistor, and a digital potentiometer. It should be noted that, since the controllable resistor can change its resistance or control a switch by adjusting the input voltage or current signal, in this embodiment, at least two controllable resistors can be connected in parallel to achieve control over the direction of current conduction. The controllable resistor is connected in series in a three-dimensional wire mesh and is controlled by the controller.

[0039] In one alternative embodiment, the magnetic field sensor includes at least one of a magnetoresistive sensor, a fluxgate sensor, an optical pump sensor, a magneto-inductor, and a magnetocalor; wherein the magnetoresistive sensor includes at least one of a giant magnetoresistive (GMR), anisotropic magnetoresistive (AMR), tunneling magnetoresistive (TMR), and Hall effect sensor.

[0040] In one optional embodiment, the coil's enclosure of the target area can be open or closed; the coil can be a continuous whole or multiple separate components. In other words, the target area can be selected based on the coil's position, with the center of symmetry as the sphere's center and a radius of a preset value. The preset value can be determined according to actual design requirements, such as 20cm.

[0041] In one possible implementation, the controller is used to obtain the magnetic field of the target area based on the received position signal and magnetic field signal. In other words, the controller includes: an information acquisition unit, which obtains coil attitude information based on the position signal and coil magnetic field information based on the magnetic field signal; a relationship acquisition unit, which, based on the coil attitude information and coil magnetic field information, and in combination with the current information of each current segment of the coil and the pre-acquired position information of the target area, uses Biot-Savart's law to obtain the magnetic field relationship between each current segment of the coil and the characteristic point magnetic field of the target area, and the position magnetic field relationship between each current segment and the magnetic field sensor; and a magnetic field acquisition unit, which, based on the characteristic point magnetic field relationship and the position magnetic field relationship, and in combination with the current of each current segment of the coil, obtains the magnetic field of the target area. It should be added that by acquiring the position and orientation information of the coil, the overall deflection angle of the coil can be obtained, which facilitates determining the corresponding attitude of the coil based on the overall deflection angle.

[0042] Furthermore, the relationship acquisition unit is used to obtain the magnetic field relationship between each current segment of the coil and the feature point of the target area, as well as the position magnetic field relationship between each current segment and the magnetic field sensor. In other words, the relationship acquisition unit includes: a first position acquisition subunit, which selects feature points from the target area based on the pre-acquired position information of the target area to obtain the feature point position information; a second position acquisition subunit, which obtains the position information of each current segment based on the coil attitude information and the pre-acquired position relationship between the position sensor and each current segment of the coil; and a relationship acquisition subunit, which, based on the feature point position information, the position information of each current segment, the current information of each current segment of the coil, and the coil magnetic field information, uses Biot-Savart's law to obtain the magnetic field relationship between each current segment and the feature point of the target area, as well as the position magnetic field relationship between each current segment and the magnetic field sensor.

[0043] It should be added that the relationship between each current segment and the characteristic magnetic field of the target region is expressed as follows:

[0044] B tI =Mt I

[0045] Among them, B tI M represents the magnetic field of the target region. t This indicates the relationship between each current segment and the characteristic magnetic field of the target region, where I represents the current information of each current segment of the coil.

[0046] The position and magnetic field relationships between each current segment and the magnetic field sensor are expressed as follows:

[0047] B sI =M sI

[0048] Among them, B sI M represents the coil's magnetic field information. s This indicates the position and magnetic field relationship between each current segment and the magnetic field sensor, where I represents the current information of each current segment of the coil.

[0049] In addition, the magnetic field of the target region is represented as:

[0050] B t (t1)=f(B s (t1)-M s I(t1))+M t I(t1)

[0051] Among them, B t (t1) represents the magnetic field of the target region, B s (t1) represents the coil magnetic field information, M s M represents the position and magnetic field relationship between each current segment and the magnetic field sensor. t This represents the relationship between each current segment and the characteristic magnetic field of the target region, and I(t1) represents the current information of each current segment of the coil.

[0052] In another possible implementation, the controller is further configured to: obtain coil magnetic field information based on the magnetic field signal when there is no current in the coil; and estimate the magnetic field distribution of the target region based on the coil magnetic field information to obtain the magnetic field of the target region.

[0053] Specifically, the controller is also used to estimate the magnetic field distribution of the target area based on the magnetic field signal. In other words, the controller also includes: a Taylor expansion unit, which performs Taylor expansion on the magnetic field signal according to the spatial coordinates in the Cartesian coordinate system or the spherical coordinate system to obtain the Taylor expansion result; and a fitting unit, which removes the higher-order parameters in the Taylor expansion result based on a preset threshold and fits the Taylor expansion result after removing the higher-order parameters.

[0054] In this embodiment, it should be added that the magnetic field of the target region is represented as:

[0055] Bt =f(B s )

[0056] Among them, B t Target region magnetic field, B s This indicates information about the coil's magnetic field.

[0057] In one optional embodiment, the controller adjusts the coil current based on the magnetic field of the target region after obtaining the magnetic field. Specifically, the controller further includes: a current determination unit for determining the coil current at the next moment based on the magnetic field of the target region; and an adjustment unit for adjusting the current of the coil according to the required current magnitude. It should be noted that by changing the total coil current and controlling the variable resistor, the current in the coil is made consistent with the current at the next moment, thereby achieving magnetic field control.

[0058] Furthermore, the current determination unit includes: a first current acquisition subunit, which obtains the preliminary current at the next moment based on the magnetic field of the target area, the current of each current segment of the coil, and the magnetic field relationship between each current segment and the characteristic point of the target area, and in combination with a preset threshold and Kirchhoff's current law; and a second current acquisition subunit, which optimizes the preliminary current at the next moment to obtain the coil current at the next moment.

[0059] It should be added that the coil current at the next moment is expressed as... Furthermore:

[0060]

[0061] Among them, M t This represents the relationship between each current segment and the characteristic magnetic field of the target region; I(t2) represents the initial current at the i-th next moment; I(t1) represents the current information of each current segment of the coil, that is, the current of each current segment of the coil; B t (t1) represents the magnetic field of the target area; A represents the preset threshold. The preset threshold can be determined according to the actual magnetic field value in the target area to be controlled. For example, when it is 1nT, it means that the magnetic field in the target area needs to be controlled to be less than 1nT. This indicates that Kirchhoff's Current Law must be satisfied, meaning the sum of the currents at each node must be zero, where N represents the node number. i This represents the current of the i-th node connected to the corresponding node.

[0062] In one optional embodiment, the current distribution in the programmable coil can be adjusted by controlling a controllable resistor via a controller, actively applying a magnetic field to the target area to counteract magnetic field changes, thereby achieving magnetic field shielding in the target area. The programmable coil can be placed outside the target area to shield against external magnetic fields, or it can cancel the magnetic field of the magnetic source in the target area, reducing the influence of the magnetic source on the magnetic field of the external area.

[0063] In an alternative embodiment, the system further includes a power source for supplying power to the system and regulating the total current in the coil.

[0064] In one optional embodiment, the coil consists of two independent planes, each measuring 2m x 2m x 2cm. Each plane is primarily made of polymethyl methacrylate (PMMA) and is a fixed structure with a spacing of 0.5m. Each coil contains five layers of coil structure, each layer composed of 1mm diameter copper wire. Different layers are connected by 1mm diameter copper wire, forming a three-dimensional grid structure. Each grid is 1cm x 1cm x 5mm in size. A transistor is connected in series in each segment of copper wire forming the grid, and the transistor is controlled by a controller. Additionally, a fluxgate magnetic field sensor and a position sensor are arranged at the center of selected grid areas. Sensor information is collected and processed by the controller. The coils, controller, fluxgate sensor, and position sensor are all powered by a power supply.

[0065] In one optional embodiment, the coil is a flexible cylindrical surface with a curved surface size of φ10cm*10cm and a thickness of 1mm, primarily made of polyurethane. The programmable coil comprises a 5-layer coil structure, each layer consisting of copper wire with a diameter of 0.01mm. Different layers are connected by copper wires with a diameter of 0.01mm, forming a three-dimensional mesh structure. Each mesh is 0.1mm*0.1mm*0.1mm in size. A field-effect transistor is connected in series in each copper wire segment constituting the mesh, controlled by a controller. Above the copper wire structure, a giant magnetoresistive magnetic field sensor and a position sensor are arranged, with sensor information collected and processed by the controller. The programmable coil, controller, fluxgate sensor, and attitude sensor are all powered by a power supply.

[0066] It should be noted that the difference between this embodiment and the previous embodiment is that the position signal of the position sensor is read in real time to facilitate timely updates of the magnetic field relationship of the feature points and the position magnetic field relationship. It should be noted that the target area is a flexible cylindrical surface-wrapped area to reduce the influence of the target area's magnetic field on the external environment. Furthermore, to improve efficiency, the shape of the programmable coil can be adjusted to achieve complete coverage of the target area.

[0067] In summary, the embodiments of the present invention transmit information from position sensors and magnetic field sensors to the controller in real time. By using the position signals from the position sensors and the position information of the target area, the magnetic field relationship between each current segment of the coil and the characteristic point magnetic field of the target area is determined. Combined with the magnetic field signals from the magnetic field sensors, the magnetic field of the target area is determined, and the required current of the coil at the next moment is obtained. The controller then changes the coil current to control the magnetic field of the target area within the required range, thereby achieving magnetic field control.

[0068] The magnetic field control method provided by the present invention is described below. The magnetic field control method described below can be referred to in correspondence with the magnetic field control system described above.

[0069] Figure 4 A flowchart of a magnetic field control method is shown. Applying the magnetic field control system described above, the method is executed by a controller and includes:

[0070] S41, receive a position signal sent by a position sensor, the position signal including position information and direction information, and receive a magnetic field signal sent by a magnetic field sensor;

[0071] S42 obtains the magnetic field of the target area based on the received position signal and magnetic field signal, and adjusts the coil current distribution according to the magnetic field of the target area to achieve magnetic field control.

[0072] In step S42, the magnetic field of the target area is obtained based on the received position signal and magnetic field signal, including: obtaining coil attitude information based on the position signal and obtaining coil magnetic field information based on the magnetic field signal; obtaining the relationship between the magnetic field of each current segment of the coil and the characteristic magnetic field of the target area, and obtaining the relationship between the magnetic field of each current segment of the coil and the position magnetic field of the magnetic field sensor based on the coil attitude information and the coil magnetic field information, combined with the current information of each current segment of the coil and the pre-acquired position information of the target area, using Biot-Savart's law; obtaining the magnetic field of the target area based on the characteristic magnetic field relationship and the position magnetic field relationship, combined with the current of each current segment of the coil.

[0073] Furthermore, obtaining the magnetic field relationship between each current segment of the coil and the characteristic point magnetic field of the target area, as well as the position magnetic field relationship between each current segment and the magnetic field sensor, includes: selecting characteristic points from the target area based on the pre-acquired position information of the target area to obtain the position information of the characteristic points; obtaining the position information of each current segment based on the coil attitude information and the pre-acquired position relationship of the position sensor relative to each current segment of the coil; and obtaining the magnetic field relationship between each current segment and the characteristic point magnetic field of the target area, as well as the position magnetic field relationship between each current segment and the magnetic field sensor, using Biot-Savart's law based on the characteristic point position information, the position information of each current segment, the current information of each current segment of the coil, and the coil magnetic field information.

[0074] In another possible implementation, the method further includes: obtaining coil magnetic field information based on the magnetic field signal when there is no current in the coil; estimating the magnetic field distribution of the target region based on the coil magnetic field information to obtain the magnetic field of the target region.

[0075] Specifically, the estimation of the magnetic field distribution in the target area based on the magnetic field signal includes: performing a Taylor expansion of the magnetic field signal according to the spatial coordinates in a Cartesian or spherical coordinate system to obtain the Taylor expansion result; removing higher-order parameters from the Taylor expansion result based on a preset threshold, and fitting the Taylor expansion result after removing higher-order parameters.

[0076] Furthermore, after obtaining the magnetic field of the target region, the process includes adjusting the coil current based on the magnetic field. Specifically, adjusting the coil current based on the magnetic field includes: determining the coil current at the next moment based on the magnetic field; and adjusting the current of the coil according to the required current magnitude. It should be noted that by changing the total coil current and controlling the variable resistor, the current in the coil is made consistent with the current at the next moment, thereby achieving magnetic field control.

[0077] Further, based on the magnetic field of the target region, the coil current at the next moment is determined, including: obtaining the preliminary current at the next moment based on the magnetic field of the target region, the current of each current segment of the coil, and the magnetic field relationship between each current segment and the characteristic point of the target region, combined with a preset threshold and Kirchhoff's current law; and optimizing based on the preliminary current at the next moment to obtain the coil current at the next moment.

[0078] In summary, the embodiments of the present invention transmit information from position sensors and magnetic field sensors to the controller in real time. By using the position signals from the position sensors and the position information of the target area, the magnetic field relationship between each current segment of the coil and the characteristic point magnetic field of the target area is determined. Combined with the magnetic field signals from the magnetic field sensors, the magnetic field of the target area is determined, and the required current of the coil at the next moment is obtained. The controller then changes the coil current to control the magnetic field of the target area within the required range, thereby achieving magnetic field control.

[0079] Figure 5 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 5 As shown, the electronic device may include a processor 51, a communication interface 52, a memory 53, and a communication bus 54. The processor 51, communication interface 52, and memory 53 communicate with each other via the communication bus 54. The processor 51 can call logical instructions in the memory 53 to execute a magnetic field control method. This method includes: receiving a position signal sent by a position sensor and receiving a magnetic field signal sent by a magnetic field sensor; the position signal including position information and direction information; obtaining the magnetic field of the target area based on the received position signal and magnetic field signal; and adjusting the coil current distribution according to the magnetic field of the target area to achieve magnetic field control.

[0080] Furthermore, the logical instructions in the aforementioned memory 53 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, or the part that contributes to the prior art, or a part 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 to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0081] On the other hand, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the magnetic field control method provided by the above methods. The method includes: receiving a position signal sent by a position sensor and receiving a magnetic field signal sent by a magnetic field sensor, wherein the position signal includes position information and direction information; obtaining the magnetic field of a target area based on the received position signal and magnetic field signal, and adjusting the coil current distribution according to the magnetic field of the target area to achieve magnetic field control.

[0082] In another aspect, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the magnetic field control method provided by the above methods. The method includes: receiving a position signal sent by a position sensor and receiving a magnetic field signal sent by a magnetic field sensor, the position signal including position information and direction information; obtaining a magnetic field of a target area based on the received position signal and magnetic field signal, and adjusting the coil current distribution according to the magnetic field of the target area to achieve magnetic field control.

[0083] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0084] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A magnetic field control system, characterized in that, It includes a coil, a magnetic field sensor, a position sensor, and a controller, among which: The position sensor is fixed in the coil and is used to acquire the position signal of the coil and transmit the position signal to the controller. The position signal includes position information and direction information. The magnetic field sensor is fixed in the coil and is used to acquire the magnetic field signal of the coil and transmit the magnetic field signal to the controller; The controller obtains the magnetic field of the target area based on the received position signal and magnetic field signal, and adjusts the coil current distribution according to the magnetic field of the target area to achieve magnetic field control; The coil comprises a flexible cylindrical surface, a three-dimensional conductor grid, and a controllable resistor array, wherein: The three-dimensional conductor grid is formed by connecting conductive components through preset nodes; The flexible cylindrical surface is coated on the three-dimensional conductor grid; The controllable resistor group includes multiple controllable resistors connected in parallel. The controllable resistor group is connected in parallel in the three-dimensional conductor grid, and the controllable resistor group is controlled by the controller.

2. The magnetic field control system according to claim 1, characterized in that, The process of obtaining the magnetic field of the target area based on the received position signal and magnetic field signal includes: Based on the position signal, coil attitude information is obtained, and based on the magnetic field signal, coil magnetic field information is obtained; Based on the coil attitude information and the coil magnetic field information, and combined with the current information of each current segment of the coil and the pre-acquired position information of the target area, the characteristic magnetic field relationship between each current segment of the coil and the target area is obtained using Biosavart's law, as well as the position magnetic field relationship between each current segment and the magnetic field sensor. Based on the magnetic field relationship of the characteristic points and the magnetic field relationship of the position, and combined with the current of each current segment of the coil, the magnetic field of the target area is obtained.

3. The magnetic field control system according to claim 2, characterized in that, The process of obtaining the magnetic field relationship between each current segment of the coil and the characteristic point magnetic field of the target region, and obtaining the position magnetic field relationship between each current segment and the magnetic field sensor, includes: Based on the pre-acquired location information of the target area, feature points are selected from the target area to obtain feature point location information; based on the coil attitude information and the pre-acquired positional relationship between the position sensor and each current segment of the coil, the location information of each current segment is obtained. Based on the feature point location information, the location information of each current segment, the current information of each current segment of the coil, and the magnetic field information of the coil, the magnetic field relationship between each current segment and the feature point of the target area is obtained using Biot-Savart's law, as well as the position magnetic field relationship between each current segment and the magnetic field sensor.

4. The magnetic field control system according to claim 1, characterized in that, The controller is also used for: In the absence of current in the coil, the coil magnetic field information is obtained based on the magnetic field signal; The magnetic field distribution of the target region is estimated based on the magnetic field information of the coil, and the magnetic field of the target region is obtained.

5. The magnetic field control system according to claim 4, characterized in that, The estimation of the magnetic field distribution in the target region based on the magnetic field signal includes: In Cartesian or spherical coordinate systems, the magnetic field signal is expanded using Taylor expansion based on spatial coordinates to obtain the Taylor expansion result. Based on a preset threshold, higher-order parameters in the Taylor expansion result are removed, and the Taylor expansion result after removing higher-order parameters is fitted.

6. The magnetic field control system according to claim 1, characterized in that, The step of adjusting the coil current according to the magnetic field of the target region includes: Determine the coil current at the next moment based on the magnetic field of the target region; The current current of the coil is adjusted according to the coil current at the next moment.

7. The magnetic field control system according to claim 1, characterized in that, The material of the flexible cylindrical surface includes at least one of polyurethane, polymethyl methacrylate, and polyimide.

8. The magnetic field control system according to claim 1, characterized in that, The magnetic field sensor includes at least one of magnetoresistive sensor, fluxgate sensor, optical pump sensor, magneto-inductor and magneto-capacitor; wherein the magnetoresistive sensor includes at least one of giant magnetoresistive (GMR), anisotropic magnetoresistive (AMR), tunneling magnetoresistive (TMR) and Hall effect sensor.

9. A magnetic field control method, employing the magnetic field control system as described in any one of claims 1-8, characterized in that, include: The system receives position signals sent by a position sensor, the position signals including position information and direction information, and also receives magnetic field signals sent by a magnetic field sensor. Based on the received position signal and magnetic field signal, the magnetic field of the target area is obtained, and the coil current distribution is adjusted according to the magnetic field of the target area to achieve magnetic field control.

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