Closed-loop control multi-type magnetic field magnetic control system based on eight-axis electromagnetic coil

Abstract

The invention discloses a closed-loop control multi-type magnetic field magnetic control system based on eight-axis electromagnetic coils, which belongs to the technical field of magnetic control and comprises an upper computer, an analog digital acquisition card, a current driver, an eight-axis electromagnetic coil group, a magnetic field sensor, imaging equipment, water cooling equipment and interaction equipment. The upper computer sends out a control signal containing a static, dynamic or self-defined composite magnetic field; the analog digital acquisition card converts the digital control signal into an analog current signal; the current driver drives the coil according to the current loop; the eight-axis coil generates a three-dimensional magnetic field, and the magnetic field sensor feeds back the magnetic field in real time to the upper computer to realize closed-loop control. The system can solve the problems of open loop, single magnetic field and the like of an existing magnetic control system, and is suitable for the fields of minimally invasive medical treatment, micro-nano robots and the like.

Description

Technical Field

[0001] This application relates to the field of magnetic control technology, and in particular to a closed-loop control magnetic control system, device, medium and equipment for multiple types of magnetic fields based on an eight-axis electromagnetic coil. Background Technology

[0002] Magnetoresistive systems are an advanced technology that uses magnetic fields to control the movement of target objects. They are widely used in minimally invasive medicine, micro- and nano-robotics, smart material manipulation, and particle swarm manipulation. These systems achieve high-precision control and motion by guiding, manipulating, and driving specific objects through external magnetic fields. Their advantage lies in non-contact precision navigation. The non-contact control achieved through external magnetic fields makes magnetoresistive systems ideal for use in complex or special environments, such as microscale control or aseptic control. In these environments, traditional mechanical navigation methods may be ineffective due to contact contamination or environmental influences, while magnetoresistive technology can penetrate objects or insulating layers through magnetic fields to achieve safe and reliable remote navigation.

[0003] One of the most common applications of magnetic control systems is in minimally invasive medicine, particularly in the navigation and control of intravascular guidewires and catheters. In this application, an external magnetic field guides the device through complex vascular networks by adjusting the position and orientation of magnetic elements. For example, magnetic guidewires can be guided by an external magnetic field system for precise positioning within blood vessels or nerves, helping surgeons reach the target surgical area more safely and quickly. Magnetic control systems are also widely used in micro- and nano-scale robotics, especially in the medical field. For instance, microrobots can be manipulated by external magnetic fields to enter the human body and perform precise drug delivery, cell manipulation, or tissue repair tasks. The advantages of this magnetic control technology lie in its precise control, non-contact operation, and ability to operate efficiently in narrow and complex environments. Magnetic control systems are also used in other areas of biomedicine, such as cell manipulation and material delivery controlled by magnetic fields. In experiments involving cells and tissues, magnetic control technology enables the movement of biomaterials with extremely high precision without causing destructive interference to the surrounding environment.

[0004] Existing magnetic control systems include various configurations, with Helmholtz coils and Maxwell coils being common. A Helmholtz coil consists of two identical coaxial circular current coils, spaced a distance equal to its radius. By symmetrically arranging these coils, the system generates a highly uniform magnetic field in the intermediate region between the two coils. Maxwell coils are structurally similar to Helmholtz coils, but differ in that they use a specific spacing to counteract the inhomogeneities of higher-order magnetic fields, resulting in a more stable magnetic field gradient. Existing technologies suffer from limitations such as a single type of magnetic field, limited space, a conflict between magnetic field strength and coil heat dissipation preventing further increases in magnetic field strength, and the open-loop nature of the control system restricting the accuracy, stability, and dynamic adjustment capabilities of the magnetic field. Summary of the Invention

[0005] The main objective of this application is to provide a closed-loop control system, device, medium, and equipment for multiple types of magnetic fields based on an eight-axis electromagnetic coil, aiming to provide a closed-loop magnetic control system that integrates magnetic field control, temperature control, and visual feedback.

[0006] To achieve the above objectives, this application provides a closed-loop control magnetic control system for multiple types of magnetic fields based on an eight-axis electromagnetic coil, comprising: Host computer, analog-to-digital data acquisition card, current driver, eight-axis electromagnetic coil assembly, magnetic field sensor; The host computer is used to send digital control signals, including arbitrary magnetic field generation signals. The arbitrary magnetic field generation signals correspond to static magnetic fields, dynamic magnetic fields, or custom composite magnetic fields. The digital control signals are used to control the position and attitude of the magnetic controlled device. The analog-to-digital acquisition card is connected to the host computer and is used to convert the digital control signals sent by the host computer into analog current signals. The current driver is connected to an analog-to-digital acquisition card and is used to receive and process analog current signals based on a current loop control strategy to generate the current signal required to drive the eight-axis electromagnetic coil group. The eight-axis electromagnetic coil group is connected to a current driver and is used to generate a corresponding magnetic field according to the received current signal, so as to realize the three-dimensional magnetic field distribution control of arbitrary direction and intensity. The magnetic field sensor is connected to the host computer and the eight-axis electromagnetic coil group respectively. It is used to monitor the changes in the magnetic field generated by the eight-axis electromagnetic coil group in real time and feed them back to the host computer for closed-loop control and dynamic adjustment of the system.

[0007] Optionally, it also includes: The imaging equipment is connected to the host computer and the eight-axis electromagnetic coil group respectively, and is used to observe the motion state of the magnetically controlled equipment in the magnetic field in real time, providing visual feedback for magnetic field control.

[0008] Optionally, it also includes: The water-cooling equipment is connected to the host computer and the eight-axis electromagnetic coil group respectively, and is used to provide heat dissipation for the eight-axis electromagnetic coil group to prevent the coil from overheating and affecting the normal operation of the system.

[0009] Optionally, it also includes: An interactive device, connected to a host computer, is used by the user to interact with the host computer to adjust the parameters of the magnetic field.

[0010] Optionally, the eight-axis electromagnetic coil group comprises eight coils; Among them, four coils in two pairs of orthogonal arrangement are placed horizontally, with the major axis of the coils forming a 90° angle with the Z-axis; The other four coils are placed below, with their major axis at 45° to the Z-axis and offset from the four coils above by 45°. The central axes of all eight coils point to the center of the workspace, and each coil is fixed by an eight-coil frame. The distance between the head of each coil and the center of the workspace is 50mm-1000mm. Optionally, each of the eight coils includes a soft magnetic core, an electromagnetic coil, and a water-cooled copper tube; The soft magnetic core is cylindrical, and its height-to-diameter ratio is between 1 and 10. The electromagnetic coil is wound around a soft magnetic core, and the ratio of the winding length to the thickness is between 0.1 and 10. The water-cooled copper tube is wound around the outer layer of the electromagnetic coil, and the winding length is the same as the length of the electromagnetic coil. The soft magnetic core extends beyond the winding range of the electromagnetic coil, and the ratio of the extended portion to the portion surrounded by the coil is between 0 and 5.

[0011] Optionally, the closed-loop control multi-type magnetic field magnetic control system based on an eight-axis electromagnetic coil includes: Optionally, the eight coil frames are made of a non-ferromagnetic material, such as aluminum alloy or titanium alloy.

[0012] Optionally, the number of current drivers is eight, and the eight current drivers are respectively connected to the eight coils of the eight-axis electromagnetic coil group to precisely adjust the output current through the current loop of the current driver; The analog-to-digital acquisition card has eight parallel signal channels, each of which is connected to one of eight current drivers. Each signal channel of the analog-to-digital acquisition card can be independently programmed and controlled.

[0013] Optionally, the interactive device includes a keyboard, a gamepad, an AR device, or a VR device; Users can program the magnetic field signal of the host computer via keyboard, or adjust the magnetic field parameters via button mapping on a gamepad, AR device, or VR device.

[0014] This application proposes a closed-loop control system, device, medium, and equipment based on an eight-axis electromagnetic coil for multi-type magnetic field control. The system includes: a host computer, an analog-to-digital data acquisition card, a current driver, an eight-axis electromagnetic coil assembly, and a magnetic field sensor. The host computer sends digital control signals, including arbitrary magnetic field generation signals, which correspond to static magnetic fields, dynamic magnetic fields, or custom composite magnetic fields. The digital control signals control the position and attitude of the magnetically controlled equipment. The analog-to-digital data acquisition card is connected to the host computer and converts the digital control signals sent by the host computer into analog current signals. The current driver is connected to the analog-to-digital data acquisition card and receives and processes the analog current signals based on a current loop control strategy to generate the current signals required to drive the eight-axis electromagnetic coil assembly. The eight-axis electromagnetic coil assembly is connected to the current driver and generates corresponding magnetic fields based on the received current signals to achieve three-dimensional magnetic field distribution control with arbitrary direction and intensity. The magnetic field sensor is connected to both the host computer and the eight-axis electromagnetic coil assembly and monitors the changes in the magnetic field generated by the eight-axis electromagnetic coil assembly in real time, feeding back the changes to the host computer for closed-loop control and dynamic adjustment of the system. The system uses a host computer to control an analog-to-digital data acquisition card and a current driver to drive an electromagnetic coil group. Combined with feedback information provided by a magnetic field sensor and imaging equipment, it forms a closed-loop magnetic control system that integrates magnetic field control, temperature control, and visual feedback. Attached Figure Description

[0015] Figure 1 This is a control system block diagram provided for an embodiment of a closed-loop control multi-type magnetic field magnetic control system based on an eight-axis electromagnetic coil, as described in this application. Figure 2 This is a physical diagram of a magnetic control system provided in an embodiment of a closed-loop control magnetic control system for multiple types of magnetic fields based on an eight-axis electromagnetic coil, as described in this application. Figure 3 This is a schematic diagram of an electromagnetic coil provided for an embodiment of a closed-loop control multi-type magnetic field magnetic control system based on an eight-axis electromagnetic coil, as described in this application.

[0016] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0017] It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0018] Because most existing magnetic control systems can generate specific types of magnetic fields (such as uniform static magnetic fields), the limited variety of magnetic fields restricts their application in various fields. Systems like Helmholtz coils are primarily used to generate static uniform magnetic fields and simple dynamic magnetic fields. While these fields are very useful in many experiments, their functionality is limited when dealing with complex field structures (such as gradient fields and vortex fields). Maxwell coils, although capable of generating gradient magnetic fields, cannot guarantee the uniformity of their magnetic fields. Traditional magnetic control systems cannot meet the demands of complex magnetic fields: for example, in smart materials, nanotechnology, and certain biological experiments, the ability to generate complex, time-varying magnetic fields (such as oscillating or periodic magnetic fields) is required. The limited variety of magnetic fields in magnetic control systems restricts their application in multifunctional magnetic control systems, such as multi-field joint experiments requiring the simultaneous generation of gradient fields, alternating fields, and rotating magnetic fields. High-precision control is also challenging. For scenarios requiring precise control of magnetic field strength and direction (such as guiding magnetic nanoparticles and controlling precision materials), static or single uniform magnetic fields cannot meet the demands of complex fields, thus limiting experimental flexibility.

[0019] Furthermore, in order to achieve a sufficiently large and uniform magnetic field, the size and layout of the coils in a magnetic control system are precisely designed. This often means that a uniform magnetic field can only be obtained in the central region of the coil (i.e., the storage space), which is usually quite small. Especially in Helmholtz coils, the distance between two coils is generally the size of the coil radius, thus limiting the size of the storage space. To provide a stable magnetic field in experiments, many magnetic control systems adopt a fully enclosed structural design. Maxwell coils and some other high-precision magnetic field systems also completely enclose the experimental area with a ring structure. This fully enclosed structure can generate a stable magnetic field in the central region, but it also limits the size of the experimental sample and the flexibility of operation. When in vivo animal experiments are required, existing magnetic control systems cannot meet the experimental requirements due to the size limitations of the experimental animals.

[0020] Existing magnetic control systems typically require increasing the current intensity through the coil to generate a stronger magnetic field. However, this increase in current leads to a significant rise in system heat generation, necessitating more complex cooling systems to maintain stable operation. Such systems consume extremely high power, and the choice of coil materials is limited due to factors such as resistive heating. Furthermore, existing magnetic control systems are often constrained by space limitations, and adding a cooling system would further reduce the available space, imposing additional design constraints and ultimately preventing further increases in magnetic field strength.

[0021] Existing magnetic control systems generally rely on open-loop control, which has several significant limitations. The lack of a closed-loop control system restricts the accuracy, stability, and dynamic adjustment capability of the magnetic field, thus affecting the controllability and precision of the experiment. An open-loop control system means that the system's output (e.g., the strength or direction of the magnetic field) is not fed back to the host computer during the control process, thus preventing real-time adjustments. Magnetic control systems often generate a magnetic field by simply adjusting the current in the coil, but they do not monitor the actual value and changes in the magnetic field in real time. Open-loop magnetic control systems do not receive real-time magnetic field information, therefore they cannot adjust the current or other parameters according to actual conditions. Open-loop control systems rely on preset current or voltage values, assuming these input values ​​will remain stable. However, fluctuations in current, changes in coil resistance, or other external disturbances can affect the actual generation of the magnetic field, leading to unstable experimental results. Due to the lack of real-time feedback, open-loop systems struggle to achieve the desired control precision in experiments requiring high-precision magnetic fields. The actual generated magnetic field may deviate from the expected value, especially when high magnetic field strength is required, these deviations can be more significant. For some experiments that require dynamic adjustment of the magnetic field or complex field distribution, open-loop systems cannot flexibly adjust the magnetic field according to real-time requirements, which limits the diversified control of these experiments.

[0022] Reference Figure 1 The first embodiment of this application provides a closed-loop control system for multiple types of magnetic fields based on an eight-axis electromagnetic coil. The closed-loop control system for multiple types of magnetic fields based on an eight-axis electromagnetic coil may include: a host computer, an analog-to-digital data acquisition card, a current driver, an eight-axis electromagnetic coil group, and a magnetic field sensor.

[0023] The host computer is used to send digital control signals, including arbitrary magnetic field generation signals. The arbitrary magnetic field generation signals correspond to static magnetic fields, dynamic magnetic fields, or custom composite magnetic fields. The digital control signals are used to control the position and attitude of the magnetic controlled device.

[0024] The static magnetic field includes uniform magnetic fields and gradient magnetic fields, while the dynamic magnetic field includes oscillating magnetic fields and rotating magnetic fields. Custom composite magnetic fields can be configured by the user to combine multiple magnetic field types according to specific experimental or application needs. Specifically, the magnetically controlled devices encompass magnetic particles, magnetic wires, and magnetic microrobots, adapting to various scenarios such as minimally invasive medical procedures, micro-nano robot manipulation, and intelligent material control. Clearly, by enabling the generation of multiple types of magnetic field signals through a host computer, the problem of existing magnetic control systems having a limited range of magnetic field types (e.g., only able to generate uniform static magnetic fields or magnetic fields in a single direction) can be solved.

[0025] The analog-to-digital acquisition card is connected to the host computer and is used to convert the digital control signals sent by the host computer into analog current signals.

[0026] The current driver is connected to an analog-to-digital acquisition card and is used to receive and process analog current signals based on a current loop control strategy to generate the current signals required to drive the eight-axis electromagnetic coil group.

[0027] The current loop control strategy can monitor the output current of the current driver in real time and compare and adjust it with a preset current value to ensure the stability of the output current. Specifically, after receiving an analog current signal, the current driver adjusts the amplitude and variation of its output current according to the signal strength and frequency to match the current requirements of the eight-axis electromagnetic coil group.

[0028] The eight-axis electromagnetic coil group is connected to a current driver and is used to generate a corresponding magnetic field according to the received current signal, so as to realize the three-dimensional magnetic field distribution control of arbitrary direction and intensity.

[0029] The eight-axis design enables control of three-dimensional magnetic field distribution with arbitrary direction and intensity, adapting to diverse needs for manipulating magnetic materials. The electromagnetic coil assembly can generate any desired magnetic field for better manipulation of magnetic materials. Specifically, the layout of the eight coils allows them to apply magnetic fields to the center of the workspace from different directions. By adjusting the magnitude and direction of the current in each coil, a three-dimensional magnetic field of arbitrary direction and intensity can be synthesized. For example, when a rotating magnetic field needs to be generated, the continuous rotation of the magnetic field direction can be achieved by adjusting the timing of current changes in different coils according to a specific rule. The design of the eight-axis electromagnetic coil assembly solves the problems of existing magnetic control systems being unable to achieve omnidirectional magnetic field control or having limited space. It can generate an omnidirectional three-dimensional magnetic field, and the optimized coil layout expands the workspace, adapting to the magnetic field manipulation needs of larger objects (such as laboratory animals).

[0030] The magnetic field sensor is connected to the host computer and the eight-axis electromagnetic coil group respectively. It is used to monitor the changes in the magnetic field generated by the eight-axis electromagnetic coil group in real time and feed them back to the host computer for closed-loop control and dynamic adjustment of the system.

[0031] The magnetic field sensor, based on Hall's law, monitors the magnetic field and converts the detected magnetic field strength and direction into voltage signals. Specifically, the magnetic field sensor transmits feedback signals back to the host computer in real time. The host computer compares the actual magnetic field parameters with preset target parameters. If a deviation exists, it adjusts the output digital control signal, forming a closed-loop control. Clearly, the closed-loop control formed by the magnetic field sensor and the host computer solves the problems of low accuracy and inability to adjust the magnetic field in real time in existing open-loop control systems. It can correct magnetic field deviations in real time, ensuring that the magnetic field strength and direction always meet expectations, significantly improving the accuracy and stability of magnetic field control. In one embodiment of this application, the closed-loop control multi-type magnetic field magnetic control system based on an eight-axis electromagnetic coil further includes: an imaging device, which is connected to the host computer and the eight-axis electromagnetic coil group respectively, for real-time observation of the motion state of the magnetically controlled device in the magnetic field, and provides visual feedback for magnetic field regulation.

[0032] The imaging device can be selected according to the scale of the magnetically controlled device. For example, a microscope can be used when manipulating microscopic magnetic microrobots, while a suitable in vivo imaging device can be used for in vivo animal experiments. Specifically, the imaging device converts the observed motion state of the magnetically controlled device (such as position changes and posture adjustments) into image or video signals and transmits them to a host computer, which the operator can view. It is understood that the visual feedback provided by the imaging device solves the problem of not being able to intuitively monitor the motion state of the magnetically controlled device in existing technologies, enabling the operator to adjust the magnetic field parameters in real time according to the actual motion situation. This significantly improves the accuracy and controllability of magnetic field regulation, especially in microscopic manipulation or complex environments (such as intravascular guidewire navigation).

[0033] In one embodiment of this application, the closed-loop control multi-type magnetic field magnetic control system based on an eight-axis electromagnetic coil further includes: a water-cooling device, which is connected to the host computer and the eight-axis electromagnetic coil group respectively, and is used to provide heat dissipation for the eight-axis electromagnetic coil group to avoid overheating of the coils and affecting the normal operation of the system.

[0034] The water-cooling device includes cooling copper pipes, coolant, a water tank, and a temperature sensor. Specifically, the cooling copper pipes are wound around the outer layer of the electromagnetic coil, and the coolant circulates within the cooling copper pipes to carry away the heat generated during coil operation. The temperature sensor monitors the coil temperature in real time and transmits the temperature data to a host computer. If the temperature exceeds a threshold, the host computer can adjust the output current of the current driver or control the water-cooling device to enhance heat dissipation. Undoubtedly, the design of the water-cooling device resolves the contradiction between magnetic field strength and coil heat dissipation in existing technologies (such as increasing the current to enhance the magnetic field strength leading to coil overheating, and the lack of an effective heat dissipation solution). It can maintain a suitable coil temperature under high current and strong magnetic field conditions, preventing coil overheating from affecting system stability or lifespan, while also providing heat dissipation assurance for increasing magnetic field strength.

[0035] In one embodiment of this application, the closed-loop control multi-type magnetic field magnetic control system based on an eight-axis electromagnetic coil further includes: an interactive device connected to a host computer, used for users to interact with the host computer to adjust the parameters of the magnetic field.

[0036] The interactive device provides users with diverse operating methods. For example, operators can directly program magnetic field signals via the keyboard to achieve automated magnetic field control. They can also manually adjust magnetic field parameters (such as magnetic field strength and direction switching) in real time via button mapping on the controller. Optionally, AR / VR devices can provide an immersive operating interface, improving the convenience of complex magnetic field control. Specifically, the interactive device solves the problem of limited operating methods in existing magnetic control systems, meeting the operating habits and application scenario needs of different operators, lowering the system's operating threshold, and improving the real-time performance and flexibility of magnetic field parameter adjustment.

[0037] In one embodiment of this application, the eight-axis electromagnetic coil assembly comprises eight coils. Two pairs of orthogonal coils (four coils each) are placed horizontally, with their major axes forming a 90° angle with the Z-axis. The other four coils are positioned below, with their major axes forming a 45° angle with the Z-axis and offset from the four coils above them by a 45° angle. The central axes of all eight coils point to the center of the workspace and are fixed by eight coil frames. The distance from the head of each coil to the center of the workspace is 50mm-1000mm.

[0038] Specifically, the two pairs of horizontally placed orthogonal coils (with their major axes at a 90° angle to the Z-axis) are primarily used to adjust the magnetic field component in the horizontal direction. The lower coil, at a 45° angle to the Z-axis and offset from the upper coil, supplements the magnetic field components in the vertical and inclined directions, ensuring the synthesis of magnetic fields in any direction within three-dimensional space. For example, the distance between the heads of the eight coils and the center of the workspace ranges from 50mm to 1000mm, which can be selected according to the size of the object being manipulated; a smaller distance is chosen when manipulating small magnetic microrobots, while a larger distance is chosen for in vivo animal experiments. In fact, this specific layout design further clarifies the implementation method of the eight-axis electromagnetic coil group, ensuring the reliable generation of an omnidirectional three-dimensional magnetic field. Simultaneously, the adjustable distance between the coils and the center of the workspace further expands the system's applicability, adapting to the needs of controlled objects of different sizes.

[0039] In one embodiment of this application, each of the eight coils includes a soft magnetic core, an electromagnetic coil, and a water-cooled copper tube. The soft magnetic core is cylindrical, with a height-to-diameter ratio between 1 and 10. The electromagnetic coil is wound around the soft magnetic core, with a length-to-thickness ratio between 0.1 and 10. The water-cooled copper tube is wound around the outer layer of the electromagnetic coil, with a winding length equal to the length of the electromagnetic coil. The soft magnetic core extends beyond the winding range of the electromagnetic coil, with the ratio of the extended portion to the portion enclosed by the coil between 0 and 5.

[0040] The height-to-diameter ratio of the cylindrical soft magnetic core and the winding length-to-thickness ratio of the electromagnetic coil are both set according to the required magnetic field strength and focusing effect of the coil. Specifically, the water-cooled copper pipe is the same length as the electromagnetic coil to ensure uniform heat dissipation throughout the coil.

[0041] Optionally, the portion of the soft magnetic core extending beyond the coil winding area can enhance the magnetic field focusing effect. The extension ratio can be adjusted according to the magnetic field focusing requirements (e.g., the extension ratio is 0 when focusing is not required, and the extension ratio increases when strong focusing is required).

[0042] In one embodiment of this application, the material of the eight coil frames is a non-ferromagnetic material, which is an aluminum alloy or a titanium alloy.

[0043] Aluminum alloy or titanium alloy was chosen as the coil frame material because these two materials are non-ferromagnetic and will not be magnetized by a magnetic field, thus avoiding interference with the magnetic field generated by the eight-axis electromagnetic coil assembly. Specifically, non-ferromagnetic materials also possess a certain structural strength, which can stably fix the positions of the eight coils, ensuring that the coil layout does not shift.

[0044] In one embodiment of this application, the number of current drivers is eight, and each of the eight current drivers is connected one-to-one with one of the eight coils of the eight-axis electromagnetic coil group, so as to precisely adjust the output current through the current loop of the current driver. The analog-to-digital acquisition card has eight parallel signal channels, each of which is connected one-to-one with one of the eight current drivers, and each signal channel of the analog-to-digital acquisition card can be independently programmed and controlled.

[0045] The system comprises eight current drivers, each corresponding to one of the eight coils, enabling independent and precise control of the current in each coil. This avoids interference caused by multiple coils sharing a single current driver. Specifically, the eight independent programming signal channels of the analog-to-digital acquisition card provide independent analog current signals to each current driver, ensuring that control commands for each coil do not affect each other. For example, when adjusting the current of a particular coil to fine-tune the magnetic field direction, adjustment is only required through the corresponding signal channel and current driver, without affecting the currents of other coils.

[0046] In one embodiment of this application, the interactive device includes a keyboard, a gamepad, an AR device, or a VR device. Users can program the magnetic field signal to the host computer via the keyboard, or adjust the magnetic field parameters via button mapping on the gamepad, AR device, or VR device.

[0047] The keyboard is suitable for scenarios requiring precise programming control of the magnetic field (such as pre-programming complex magnetic field changes), the gamepad is suitable for scenarios requiring manual real-time adjustment of the magnetic field (such as manually guiding the movement of a magnetic guide wire), and the AR / VR device is suitable for scenarios requiring intuitive perception of the spatial distribution of the magnetic field (such as complex three-dimensional magnetic field control). Specifically, the button mapping function allows users to customize the magnetic field adjustment functions corresponding to the buttons on the gamepad and AR / VR device according to their habits (such as increasing the magnetic field strength for a certain button, or switching the magnetic field direction for another button).

[0048] In another embodiment of this application, the control flow of the magnetic control system is as follows: First, the user inputs operation commands via an interactive device such as a keyboard or gamepad. The host computer generates corresponding control signals based on these commands. These signals are converted from digital signals to analog current signals via an AD card and then transmitted to the current driver. The current driver drives an electromagnetic coil assembly based on the received analog signals. The electromagnetic coil assembly generates the required magnetic field through the corresponding current. The change in the magnetic field acts on the magnetically controlled device, such as a magnetic microrobot or other magnetic materials, thereby achieving precise control over the position and attitude of these devices.

[0049] Meanwhile, the system uses Hall effect sensors and other magnetic field sensors to detect changes in the magnetic field generated by the electromagnetic coil in real time, and transmits these feedback signals back to the host computer to achieve closed-loop control. The host computer adjusts the magnetic field output based on the feedback information from the magnetic field sensors to ensure precise magnetic field control. During the control process, water cooling equipment is used to dissipate heat from the electromagnetic coil assembly, preventing overheating of the electromagnetic coils from affecting the normal operation of the system. Temperature sensors monitor the operating temperature of the electromagnetic coils; if the temperature is abnormal, the host computer adjusts the system based on the feedback information to ensure safe operation. In addition, imaging equipment is used to observe the movement status of the magnetically controlled equipment, providing visual feedback. Operators can monitor the position and movement of the equipment in real time through the imaging equipment and make adjustments via the host computer when necessary to achieve precise control of the magnetic material.

[0050] The system uses an AD card and a current driver controlled by a host computer to drive the electromagnetic coil group. Combined with feedback information provided by a magnetic field sensor and imaging equipment, it forms a closed-loop magnetic control system that integrates magnetic field control, temperature control, and visual feedback.

[0051] The advantages of this invention are as follows: 1. Closed-Loop Control System. The magnetic control system of this invention introduces closed-loop control, which monitors parameters such as magnetic field strength and direction in real time through a magnetic field sensor and feeds this data back to the host computer. The host computer dynamically adjusts the current output of the current driver based on the feedback information to ensure that the generated magnetic field is consistent with the expected result. This closed-loop control effectively overcomes the limitations of existing open-loop control systems, improving the control accuracy, stability, and dynamic adjustment capability of the magnetic field. Compared with existing open-loop systems, this invention can adjust the magnetic field output in real time, avoiding control deviations caused by external interference or equipment errors, and ensuring the reliability of experimental results.

[0052] 2. Support for diverse magnetic field types. This invention supports the generation of various magnetic field types, including static magnetic fields (such as uniform magnetic fields and gradient magnetic fields), dynamic magnetic fields (such as oscillating magnetic fields and rotating magnetic fields), and custom composite magnetic fields. This flexibility significantly improves the system's adaptability, meeting the needs of different experiments, especially in complex applications such as nanotechnology, smart materials, and micro / nano robots. Compared to the limitations of existing technologies that only offer a single type of magnetic field, the multi-axis electromagnetic coil design of this invention enables the system to generate diverse magnetic fields, greatly expanding its application range.

[0053] 3. Increased storage space. Existing magnetic control systems typically have limited storage space due to coil structure constraints. This invention, through optimized layout of the eight-axis electromagnetic coil, not only generates a uniform magnetic field in the working area but also increases the volume of the magnetic field's effective area. Compared to traditional Helmholtz and Maxwell coils, this invention significantly improves space utilization and magnetic field distribution, making it suitable for manipulating larger objects, especially excelling in experiments involving large objects in minimally invasive medical settings.

[0054] 4. High-efficiency heat dissipation system. This invention is equipped with a water-cooling system, which effectively dissipates heat from the electromagnetic coil assembly, avoiding overheating problems during high-current operation. This water-cooling system, combined with closed-loop feedback from a temperature sensor, allows the host computer to monitor the coil temperature in real time and dynamically adjust system parameters based on the temperature feedback information, ensuring the system maintains a stable operating temperature during high-power operation. Compared to existing technologies, this invention resolves the contradiction between magnetic field strength and coil heat dissipation through efficient heat dissipation, enabling the continuous generation of a strong magnetic field under high-power operating conditions without affecting system performance.

[0055] 5. Visual Feedback and Ease of Operation. This invention is equipped with imaging devices, such as microscopes, enabling real-time observation of the movement of the magnetically controlled equipment and providing visual feedback. Operators can intuitively monitor and adjust the magnetic field signal using image information from the imaging device and the host computer, thereby achieving precise control of magnetic equipment in microscopic or complex environments. Furthermore, interactive devices (such as keyboards and gamepads) further enhance the system's ease of operation, allowing operators to adjust magnetic field parameters manually or through programming, greatly improving the flexibility of experimental operations.

[0056] This invention overcomes many shortcomings of existing magnetic control systems, providing more flexible, precise, and stable magnetic field control capabilities. It is suitable for a variety of complex applications, including minimally invasive medicine, intelligent material manipulation, and micro / nano robotics. Its efficient heat dissipation design, closed-loop control system, and diverse magnetic field generation capabilities ensure the system's wide applicability under high precision and stability requirements.

[0057] In one alternative embodiment, the soft magnetic core can be a variable iron core. The soft magnetic core used in this invention is the simplest cylindrical type, and the front end of the iron core can be processed into a conical shape to change the focusing form of the magnetic field.

[0058] It should be noted that different numbers of electromagnets can also achieve the same semi-enclosed effect. For example, the number of horizontally placed coils can be different from the number in this invention (two pairs of four coils orthogonally distributed). The number of coils below can also be different from the number in this invention (four coils symmetrically arranged in the center).

[0059] Furthermore, electromagnetic coils do not necessarily have to be cylindrical; square or conical electromagnets can also achieve similar magnetic field generation effects.

[0060] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A closed-loop control magnetic control system for multiple types of magnetic fields based on an eight-axis electromagnetic coil, characterized in that, include: Host computer, analog-to-digital data acquisition card, current driver, eight-axis electromagnetic coil assembly, magnetic field sensor; The host computer is used to send digital control signals, including arbitrary magnetic field generation signals. The arbitrary magnetic field generation signals correspond to static magnetic fields, dynamic magnetic fields, or custom composite magnetic fields. The digital control signals are used to control the position and attitude of the magnetic controlled device. The analog-to-digital acquisition card is connected to the host computer and is used to convert the digital control signals sent by the host computer into analog current signals. The current driver is connected to an analog-to-digital acquisition card and is used to receive and process analog current signals based on a current loop control strategy to generate the current signal required to drive the eight-axis electromagnetic coil group. The eight-axis electromagnetic coil group is connected to a current driver and is used to generate a corresponding magnetic field according to the received current signal, so as to realize the three-dimensional magnetic field distribution control of arbitrary direction and intensity. The magnetic field sensor is connected to the host computer and the eight-axis electromagnetic coil group respectively. It is used to monitor the changes in the magnetic field generated by the eight-axis electromagnetic coil group in real time and feed them back to the host computer for closed-loop control and dynamic adjustment of the system.

2. The closed-loop control multi-type magnetic field magnetic control system based on an eight-axis electromagnetic coil as described in claim 1, characterized in that, Also includes: The imaging equipment is connected to the host computer and the eight-axis electromagnetic coil group respectively, and is used to observe the motion state of the magnetically controlled equipment in the magnetic field in real time, providing visual feedback for magnetic field control.

3. The closed-loop control multi-type magnetic field magnetic control system based on an eight-axis electromagnetic coil as described in claim 1, characterized in that, Also includes: The water-cooling equipment is connected to the host computer and the eight-axis electromagnetic coil group respectively, and is used to provide heat dissipation for the eight-axis electromagnetic coil group to prevent the coil from overheating and affecting the normal operation of the system.

4. The closed-loop control multi-type magnetic field magnetic control system based on an eight-axis electromagnetic coil as described in claim 1, characterized in that, Also includes: An interactive device, connected to a host computer, is used by the user to interact with the host computer to adjust the parameters of the magnetic field.

5. The closed-loop control multi-type magnetic field magnetic control system based on an eight-axis electromagnetic coil as described in claim 1, characterized in that, The eight-axis electromagnetic coil assembly comprises eight coils; Among them, four coils in two pairs of orthogonal arrangement are placed horizontally, with the major axis of the coils forming a 90° angle with the Z-axis; The other four coils are placed below, with their major axis at 45° to the Z-axis and offset from the four coils above by 45°. The central axes of the eight coils all point to the center of the workspace and are fixed by the eight coil frames. The distance between the head of the eight coils and the center of the workspace is 50mm-1000mm.

6. The closed-loop control multi-type magnetic field magnetic control system based on an eight-axis electromagnetic coil as described in claim 1, characterized in that, Each of the eight coils includes a soft magnetic core, an electromagnetic coil, and a water-cooled copper tube. The soft magnetic core is cylindrical, and its height-to-diameter ratio is between 1 and 10. The electromagnetic coil is wound around a soft magnetic core, and the ratio of the winding length to the thickness is between 0.1 and 10. The water-cooled copper tube is wound around the outer layer of the electromagnetic coil, and the winding length is the same as the length of the electromagnetic coil. The soft magnetic core extends beyond the winding range of the electromagnetic coil, and the ratio of the extended portion to the portion surrounded by the coil is between 0 and 5.

7. The closed-loop control multi-type magnetic field magnetic control system based on an eight-axis electromagnetic coil as described in claim 1, characterized in that, The eight coil frames are made of non-ferromagnetic materials, namely aluminum alloy or titanium alloy.

8. The closed-loop control multi-type magnetic field magnetic control system based on an eight-axis electromagnetic coil as described in claim 1, characterized in that, The number of current drivers is eight, and the eight current drivers are respectively connected to the eight coils of the eight-axis electromagnetic coil group to precisely adjust the output current through the current loop of the current driver. The analog-to-digital acquisition card has eight parallel signal channels, each of which is connected to one of eight current drivers. Each signal channel of the analog-to-digital acquisition card can be independently programmed and controlled.

9. The closed-loop control multi-type magnetic field magnetic control system based on an eight-axis electromagnetic coil as described in claim 4, characterized in that, The interactive device includes a keyboard, a gamepad, an AR device, or a VR device; Users can program the magnetic field signal of the host computer via keyboard, or adjust the magnetic field parameters via button mapping on a gamepad, AR device, or VR device.

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