Micro-nano robot swarm control method and device

Abstract

The present invention provides a method and a corresponding device for controlling a micro-nanorobot cluster, which adopts a driving method based on a rotating gradient magnetic field to drive a micro-nanorobot cluster with magnetic components as a carrier for precise drug or cell delivery. The present invention uses a plurality of electromagnetic coils driven by a programmable timing electrical signal, which can generate an equivalent centripetal force pointing to the target position in the working space area, thereby attracting the micro-cluster to converge from different directions to the target position including the diseased tissue. By changing the current input of the electromagnetic coil, the coordinates of the target position can be adjusted.

Description

Technical Field

[0001] The present invention relates to a method and device for controlling a micro-nano robot swarm, in particular to a method and device for controlling a micro-nano robot swarm based on a rotating gradient magnetic field. Background Art

[0002] As one of the forefront research fields of micro-nano technology, micro-nano robots have the characteristics of small size, light weight, and large thrust-to-weight ratio. These robots at the micro- or nano-scale have broad application prospects in the fields of sensing detection, micro-nano manufacturing, biomedicine, etc. For example, they have potential in various biomedical applications such as targeted drug delivery and biosensing. Such small machines can perform controllable motion and execute complex tasks in various complex environments through external fields (magnetic field, acoustic field, electric field, etc.), self-propulsion, and hybrid propulsion. In recent years, researchers have made amazing achievements in the manufacturing, driving, and functionalization of micro-nano robots, and various multifunctional micro-nano robots have been prepared. At present, the motion control of micro-nano robots and the research on the behavior of their swarms are still hot research topics. The energy sources for the collective behavior of micro-nano robot swarms are extensive. Magnetism and electricity, as external field energy sources, can reasonably regulate the motion of micro-nano robots. At the same time, external energy sources can also cause the collective behavior of micro-nano robots.

[0003] US Patent Application US20140225694A1 describes a method for manufacturing a microactuator that can be remotely controlled in an addressable manner, and also provides a method for remotely controlling such a microactuator. The microactuator is a composite material of two permanent magnetic materials, one of which has a high coercivity, and the other can switch the magnetization direction by an applied magnetic field. By switching the magnetization direction of the second material, the magnetisms of the two magnets either work together or cancel each other out, resulting in different "on" and "off" behaviors of the microactuator. The microactuator can be remotely switched between the "on" or "off" state by using short-duration field pulses.

[0004] US Patent US10950378B2 relates to a method and device for controlling an electromagnetic field generator system to generate a dynamic magnetic field. The method may include: establishing a dynamic model that describes the open-loop dynamics of the electromagnetic field generation system and has a unified state-space form with a time delay; configuring a controller based on the dynamic model; applying a control signal to the electromagnetic field generation system through the controller; detecting one or more feedback signals from the electromagnetic field generation system; and updating, by the controller, the control signal for controlling the electromagnetic field generation system according to a reference signal corresponding to the desired dynamic magnetic field, one or more compensated feedback signals, and the system state. To solve the time delay, modeling error, and estimating the system state, a Kalman filter and a compensator based on a Smith predictor may be equipped.

[0005] Chinese Patent CN110861111B proposes a micro-nano robot manipulation platform with the coupling effect of magnetic field and electric field, including an observation microscope, a magnetic field generating device and an electric field generating device. The movement and cluster morphology of the micro-nano robot can be controlled by the frequency and amplitude of the alternating current applied to the electric field generating device. By passing a sinusoidal signal with adjustable frequency and amplitude through the magnetic field generating device, an adjustable uniform magnetic field, a rotating magnetic field, etc. can be generated at the center of the magnetic field. Under the action of the adjustable magnetic field, the micro-nano robot can achieve specified movements and cluster behaviors. The magnetic field lifting platform can keep the magnetic field generating device suspended without contacting the observation microscope, which can greatly reduce the influence on the field of view jitter of the observation microscope. The observation microscope is used to observe the movement of the micro-nano robot in the microenvironment.

[0006] However, the practical application of micro-nano robots still faces challenges: the tiny size makes it difficult for in-vivo imaging technology to provide high resolution and contrast, posing challenges to the real-time imaging and positioning of these micro-nano robots. Moreover, there is still a lack of platforms driven by the coupling of magnetic field and / or electric field at present, and the existing platforms cannot well meet the actual experimental requirements in terms of accuracy and design rationality. Summary of the Invention

[0007] To make up for the gap in the field of micro-nano robot manipulation under the coupling action of magnetic field and / or electric field, the present invention provides a method and device for manipulating micro-nano robots using magnetic field to achieve the movement control of micro-nano robots and the behavior control of their clusters.

[0008] The present invention provides a method and corresponding device for controlling a micro-nano robot cluster. The method is based on the driving mode and driving device of a rotating gradient magnetic field, and is used to drive a magnetic micro-nano robot cluster as a carrier for precise drug or cell delivery. The micro-nano robot cluster is also called a micro-nano robot cluster, or simply a micro-cluster. The present invention uses multiple electromagnetic coils driven by a programmable timing electrical signal, which can generate an equivalent centripetal force pointing to the target position in the working space area, thereby attracting the micro-cluster to converge on the target site including the diseased tissue from different directions. By changing the current input of the electromagnetic coil, the coordinates of the target site can be adjusted.

[0009] The present invention first provides a method for controlling a micro-nano robot cluster. The micro-nano robots in the micro-nano robot cluster contain magnetic components. The method includes: placing an object containing the micro-nano robot cluster in the working space of a magnetic field generating device, where the magnetic field generating device includes a plurality of electromagnetic coils; providing input currents to the plurality of electromagnetic coils respectively to generate a gradient magnetic field in the working plane; adjusting the input currents of the plurality of electromagnetic coils to rotate the gradient magnetic field; and adjusting the position of the object in the working space and the rotation frequency of the gradient magnetic field to move and gather the micro-nano robots in the micro-nano robot cluster to a target position.

[0010] The present invention also provides a device for controlling a micro-nano robot cluster, including: a magnetic field generating device, which includes a plurality of electromagnetic coils arranged in a ring in sequence; a driving device respectively connected to the plurality of electromagnetic coils; a microcontroller unit for controlling the driving device to generate the driving current; and a workbench located at the center of the ring formed by the plurality of electromagnetic coils for placing an object containing the micro-nano robot cluster. Wherein, the driving device generates a driving current to drive each electromagnetic coil in the plurality of electromagnetic coils in sequence to generate a rotating magnetic field, and the rotating magnetic field is used to drive the micro-nano robot cluster to converge to a target position in the object.

[0011] According to an embodiment of the present invention, the position of the micro-nano robot cluster can be adjusted by changing the timing function of the input currents of the plurality of electromagnetic coils.

[0012] Wherein, the magnetic field gradient generated by the plurality of electromagnetic coils in the working space is greater than zero, and the gradient magnetic field is annularly distributed and based on the magnetic field distribution in the working plane.

[0013] Wherein, input currents can be provided to each electromagnetic coil in the plurality of electromagnetic coils in sequence to make the magnetic field direction of the gradient magnetic field rotate continuously, and the rotation frequency of the gradient magnetic field is equal to the frequency of the input current. The input current distributed to each electromagnetic coil in the plurality of electromagnetic coils can be adjusted by the microcontroller unit to change the rotation frequency of the gradient magnetic field.

[0014] According to an embodiment of the present invention, the input current of each electromagnetic coil in the plurality of electromagnetic coils is a sequential DC input electrical signal I·c i , the magnetic flux density of the gradient magnetic field is B(r, h), the rotation frequency of the gradient magnetic field is f, I is expressed as the maximum value of the input current, and the current of the i-th electromagnetic coil in the plurality of electromagnetic coils is:

[0015]

[0016]

[0017] Among them, f and t respectively represent the rotation frequency and time period of the gradient magnetic field.

[0018] The parameter ci is a correction coefficient, which belongs to empirical values and is used to adjust the current of the i-th coil.

[0019] Among them, when c1 = c2 = c3 = c4 = 1, the rotating magnetic field generates a centripetal force to attract the micro-nanorobot to gather at the target position.

[0020] In addition, the value of the parameter ci can be changed through the microcontroller unit. Among them, the value of the parameter ci has a definite mapping relationship with the target position, and when the value of the parameter ci is changed, the target position is changed.

[0021] The present invention further includes creating a mapping relationship table, which is the relationship between the value of the parameter ci and the coordinates of the target position.

[0022] As described above, the present invention provides a method and a corresponding device for generating a magnetic field based on a rotating gradient, and the magnetic field is used to gather microclusters at a target site. Therefore, the present invention solves the key requirements for generating and controlling a magnetic field based on a rotating gradient, and has the following advantages:

[0023] (1) The existing magnetic force driving method mainly uses the gradient of the magnetic field to generate magnetic force, so as to drive functional magnetic micro-nanorobots with different shapes to move to a specified position. This technology has no special requirements for the design and processing of magnetic robots and has wide adaptability. However, due to the influence of interference factors such as high viscosity, low Reynolds number, and strong electrostatic force at the micro scale, there are problems of instability, poor controllability, and weak driving ability. In the present invention, each micro-agent rotates around itself while moving forward, thereby reducing the viscous resistance and friction force on the micro-agent and improving its movement ability. The shape design of the micro-agent is still not restricted.

[0024] (2) The existing technology for realizing targeted drug delivery mainly uses biological imaging technology to obtain the characteristics of the internal environment of the organism, establishes a movement path based on the positional relationship between the magnetic robot and the targeted target area, and uses imaging feedback to drive the magnetic robot to move towards the targeted target area. This scheme has high requirements for the resolution, response speed, imaging depth, etc. of biological imaging technology. The present invention does not depend on the specific trajectory planning and real-time visual guidance of each micro-intelligent agent navigation, greatly simplifies the steps of practical application and improves its reliability.

[0025] (3) The existing methods for realizing micro-nano robot clusters are mainly applicable to micro-nano robots with specific sizes, shapes, and materials, including peanut-shaped nanoparticles, double-sided nano magnetic particles, spiral micro-nano robots, etc. Moreover, the control of the formation process of micro-nano robot clusters strongly depends on the initial distribution state of the micro-nano robots. When the concentration of micro-nano robots is lower than a specific threshold, or the cluster is dispersed due to environmental interference, the micro-nano robot cluster will become uncontrollable. The present invention can drive different magnetic micro-reagents, regardless of the characteristics such as the size, shape, and material of these magnetic micro-reagents, and is also independent of the initial distribution density. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram showing a micro-nano robot cluster control device according to an embodiment of the present invention.

[0027] Figure 2 Schematic diagram showing the driving of a magnetic micro-nano robot cluster based on a rotating gradient magnetic field in a micro-nano robot cluster control device according to an embodiment of the present invention.

[0028] Figure 3A Showing Figure 2 Schematic diagram of the reference plane and working plane of a single electromagnetic coil in Figure 3B Showing by Figure 2 Schematic diagram of the working plane generated by four electromagnetic coils in Figure 3C Showing in Figure 3A Simulation results of the unit magnetic flux density on the working plane generated by a single electromagnetic coil in

[0029] Figures 4A - 4D respectively show in Figure 2 The input current signal timing diagrams of four electromagnetic coils in according to an embodiment of the present invention.

[0030] Figures 5A - 5D Respectively showing in Figure 2 The trajectories of moving micro-nano robots to different aggregation centers by changing the input currents of four electromagnetic coils according to an embodiment of the present invention.

[0031] Figures 6A - 6D Showing in Figure 2 The mapping relationship between the target positions of the aggregation centers and the input currents of the electromagnetic coils in four electromagnetic coils according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, and the technical solutions will be described clearly and completely. It should be noted that the embodiments described below are only some specific embodiments of the present invention, rather than all implementation schemes. Based on the principles of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0033] I. Summary of the Micro-Nano Robot Cluster Control Device

[0034] This application relates to a driving device and a corresponding driving method for a micro-nano robot cluster. Magnetic micro-nano robots themselves are technologies widely adopted in recent years, and a large number of literature reports have been made on the structures of micro-nano robots and various experiments and studies on micro-nano robots.

[0035] For example, an example of a magnetically drivable micro-robot can be found in Chinese Patent Application CN113966988A. The micro-robot can be used to carry and deliver cells, and includes photocuring a photocurable material composition to form the main body of the magnetically drivable micro-robot. The photocurable material composition includes: a degradable component, a structural component, a magnetic component, and a photocuring promoting composition including a photoinitiator component and a photosensitizer component. The magnetic component may include Fe3O4 particles, such as nanoparticles of Fe3O4 particles. The magnetic component enables the main body of the micro-robot to be magnetically driven.

[0036] The solution of the present invention can be applied to various micro-nano robots and their clusters as long as they contain a magnetic component so as to be driven by a magnetic field. Those skilled in the art can decide on their own according to their actual situations and habits which micro-nano robots and their clusters, their manufacturing materials, and magnetic properties to use to implement the solution of the present invention.

[0037] Figure 1 is a schematic diagram of a micro-nano robot cluster control device according to an embodiment of the present invention, which is used to aggregate a micro-nano robot cluster based on the rotating gradient magnetic field generated by a magnetic field generating device.

[0038] As Figure 1As shown, the magnetic field generating device 2 of the micro-nano robot cluster control device includes a plurality of electromagnetic coils 11, for example, including 3 to 12 electromagnets, especially four orthogonal electromagnetic coils 11. Each electromagnetic coil 11 is respectively excited by a voltage amplifier 4 as a driving device. The voltage amplifier 4 is controlled by a microcontroller unit 5 and can be driven by an ordinary power supply 6, and the power supply 6 converts alternating current (AC) into direct current (DC). With the help of the microcontroller unit 5 and the power supply 6, the voltage amplifier 4 inputs a determined sequence of DC to each electromagnetic coil, so that the electromagnetic coil generates a rotating magnetic field. The microcontroller unit 5 is controlled by a PC (personal computer) 7. The lifting platform 19 as a workbench is located at the center of the plurality of orthogonal coils, can be rotated to different directions through a screw 14, and the height (h) of the lifting platform relative to the electromagnetic coil can be adjusted. The chamber 15 for the micro-nano robot cluster is fixed on the lifting platform 19, in which an object containing the micro-nano robot cluster can be accommodated or placed, such as the diseased part of a patient, such as Figure 2 the eyeball of the patient shown. The computer vision subsystem 16 constitutes an imaging device, which may include different digital image capture devices depending on different environments, such as an inverted optical charge coupled device (CCD) camera 17, or optical coherence tomography (OCT) 18. The working space of the generated rotating magnetic field is located in the central region of the plurality of electromagnetic coils 11, for example, it can be a square region with a side length of 15 mm.

[0039] Figure 2 It is a schematic diagram of driving a magnetic micro-nano robot cluster based on a rotating gradient magnetic field according to an embodiment of the present invention, which can be used to explain Figure 1 the working process of the micro-nano robot cluster control device of the present invention shown in Figure 2 In

[0040] Figure 2 Figure 2 Figure 2As shown by the reference numeral 10 in the drawings, when current passes through the electromagnetic coils in sequence, a static gradient magnetic field 13 distributed in a ring shape is generated. By sequentially inputting direct current (DC) to each electromagnetic coil 11 to generate a rotating magnetic field, the micro-nano robot cluster 12 can be excited to gather at the center of the generated rotating magnetic field, which is called the gathering center in this application. The position of the gathering center can be adjusted by changing the input current of the electromagnetic coils. Refer to FIGS. 4A-4D below and their detailed descriptions. Figure 2 Reference numerals 20 and 30 in [the drawings] respectively show two cases of driving the micro-nano robot cluster in blood vessels and the eyeball.

[0041] It can be understood that any electromagnetic coil capable of generating a gradient orthogonal magnetic field can be applicable to the rotating gradient-based magnetic field generating device of the present invention for gathering the micro-nano robot cluster. The present invention is not limited by a specific coil design, and any number of electromagnetic coils can also be used. For example, an example of the electromagnetic coil 11 can be seen in US Patent Application US20200357554A1, which discloses an electromagnetic device for manipulating a magnetoresponsive robot device. The electromagnetic device includes a magnetic core and one or more electromagnetic coils arranged around the magnetic core. The magnetic core includes a first part and a second part. The first part has a first cross-section and defines a first central axis. The second part extends from one side of the first part, has a second cross-section smaller than the first cross-section, and defines a second central axis parallel to the first central axis.

[0042] II. Characteristics of the Gradient Magnetic Field

[0043] Figures 3A to 3C is the magnetic field generated by the electromagnetic coils according to an embodiment of the present invention and its simulation results. Figure 2 in the drawings Figure 3A represents Figure 2 a schematic diagram of a single electromagnetic coil in [the drawings], which includes a reference plane 23 and a working plane 22 with a height h. Figure 3B represents Figure 2 a schematic diagram of the reference plane 23 and the working plane 22 generated by the four electromagnetic coils 11 in [the drawings]. Figure 3C represents the simulation result of the unit magnetic flux density B on the working plane generated by a single electromagnetic coil 11 with 3A. Among them, Bx and By are respectively the flux densities in the Figure 3A and 3B x and y directions of [the drawings], h is the height of the working plane, and x, y, and h can form an orthogonal rectangular coordinate system.

[0044] Figure 3A and Figure 3C show the simulation results of the magnetic field gradient field generated by a single electromagnetic coil 11. Figure 3AShows a schematic diagram of a magnetic system with an electromagnetic coil 11, a reference plane 23, and a working plane 22. The reference plane 23 is the horizontal plane where the point dipoles of the four electromagnetic coils are located. The distance between the reference plane 23 and the working plane 22 is denoted by h.

[0045] Figure 3C Shows the magnetic field unit flux density B unit (r, h) simulated results of a single electromagnetic coil 11 on different planes at different heights h. It can be observed that the magnetic fields generated on different planes at different heights h are all magnetic fields with gradients, and have different intensity magnitudes and density distributions. It should be noted that there are various methods for simulating and calculating magnetic fields in the art, and they can all be used in the solution of the present invention to calculate the simulated results of the magnetic field. For example, in the paper "Preformation Characterization of a Torque-Driven Magnetic Microswimmer With Multi-Segment Structure" by Liuxi Xing et al. https: / / doi.org / 10.1109 / TIE.2019.2928283 ), the research on magnetic microswimmers is disclosed, which describes the characteristics of torque-driven segmented microswimmers driven by an external oscillating magnetic field. It is considered that magnetic microswimmers exhibit various advantages in practical applications, including a simplified propulsion mechanism for non-reciprocating motion in a low Reynolds (Re) number environment, high flexibility, and high efficiency. The magnetic field calculation method in this paper can also be applied to the Figure 3C magnetic field simulation calculation of the present invention.

[0046] III. Method for generating a rotating gradient magnetic field

[0047] By sequentially activating the four electromagnetic coils 11 on the rotating plane, the direction of the magnetic field generated by the electromagnetic coils in the working space will continuously change, thereby generating an equivalent rotating magnetic field, and its rotation frequency is equal to the frequency of the electrical signal used to activate the coil 11. Figures 4A - 4D are respectively the signal timing diagrams of the input currents of the four electromagnetic coils 11 according to the embodiments of the present invention. The working space refers to Figures 3A - 3C the space where the working plane 22 is located.

[0048] Figures 4A - 4D respectively show the sequential DC input electrical signals I·c1 - I·c4 of each electromagnetic coil 11. When applying the sequential DC input Ii (i.e., I·c i) When the time is, the magnetic flux density is B(r, h), and the magnetic field rotates at a frequency of f. i is the number of the electromagnetic coil, and any number or any type of coil can be used in the present invention. In this embodiment, i is 4, indicating that 4 electromagnetic coils are used. When other numbers of coils are used, i can take other values.

[0049] Representing I as the maximum value of the current, the current in the i-th coil of the electromagnetic coil 11 can be expressed as:

[0050]

[0051]

[0052] Where f and t respectively represent the rotation frequency of the magnetic field and the time period. In real-time applications, the parameter ci can be introduced to adjust the current of the i-th electromagnetic coil, keeping I constant. By adjusting the magnitude of the parameter ci, the position of the aggregation center of the micro-nano robot can be changed. In the present invention, the maximum value I of the current represents the peak value of the unmodulated input electrical signal of each electromagnetic coil 11, which is adjusted by the constant power supply part in the control device, and the parameter ci is adjusted by the microcontroller unit. The parameter ci is the correction coefficient of the control device of the present invention and belongs to empirical values. For the selection of the values of c1 - c4 in this embodiment, reference can be made to the data in the table of Figures 6A - 6D respectively.

[0053] IV. Description of the movement of the micro-nano robot towards the aggregation center

[0054] Figures 5A - 5D are respectively the trajectories of the micro-nano robot moving towards different aggregation centers by changing the input current of the coil according to the embodiments of the present invention.

[0055] Figures 5A - 5D respectively show the movement trajectories of the micro-nano robot moving from the starting position to different aggregation centers under different parameters c = (c1, c2, c3, c4). The starting position can be freely selected by performing specific calculations or experiments, and can be selected as any value within the working space. For example, it can be selected with the center of the working plane 22 as the coordinate origin.

[0056] As Figure 5A shown, the starting positions of the movement of the micro-nano robot are respectively located at four points such as (0, 3), (3, 0), (0, -3), (-3, 0). The relationship between these coordinates and the coordinate system of the working plane or the reference plane can be referred to Figure 3B . When c1 = c2 = c3 = c4 = 1, the micro-nano robot can move and converge from these four different starting points to the center of the working space, indicating that the rotating magnetic field can generate a centripetal force to attract the micro-nano robot to converge to the target position. In Figures 5A - 5DThe trajectory of the micro-nanorobot is represented by a gray curve, which is shown as a centripetal and gradually changing curve. The curve has a certain width, indicating the possible trajectory range of the micro-nanorobot. Figures 5B - 5D Three figures respectively show the movement trajectories of the micro-nanorobot moving to different aggregation centers when the parameter c is changed. This process will be discussed in detail in the next part.

[0057] V. Method for Changing the Position of the Aggregation Center by Program Setting

[0058] Adjusting ci can be used to change the position of the aggregation center. The detailed description of this calculation process is as follows. First, the cis of the electromagnetic coils on the same axis cannot be adjusted simultaneously. That is, when adjusting the first coil (c1), the third coil (c3) in the opposite direction should be kept at the base value 1. The same applies to the adjustment methods of c2 and c4. Secondly, the change of the current always increases. That is to say, ci only increases from the base value 1, so the value of ci is always greater than or equal to 1. There are four pairs of coils for changing the coil current, namely coil combinations 1–2, 2–3, 3–4, and 4–1. Consider c = (c1, c2, c3, c4) as the parameter group of the four coils. When c = (1, 1, 1, 1), the aggregation center is located at the physical center of the working space, that is, (x, y) = (0, 0). By changing ci, the position of the new aggregation center can be calculated according to the dynamic equation. Then, establish the reverse mapping relationship from g(x, y) to c, for example, by using a neural network model or an algorithm based on reinforcement learning, etc. The dynamic equation can be obtained according to a large number of existing micro-nano hydrodynamics calculation methods in the field. The solution of the present invention is not limited to a specific dynamic equation.

[0059] Figures 6A - 6D is the mapping relationship between the position of the aggregation center and the input current of the coil according to the embodiment of the present invention. Figures 6A - 6D shows the mapping relationship between the position of the aggregation center g(x, y) and ci when a 15mm×15mm working space is divided into 15×15 unit square regions. A unit square area with a side length of 1mm is accurate enough for most clinical treatments (such as tumor treatment). For other application cases, the selection and division of the working space size can be adjusted accordingly.

[0060] It should be noted that Figures 6A - 6D the values in the shown table are the inherent properties of the electromagnetic coils in this embodiment. When the design of the electromagnetic coils is changed, the data in the table should be adjusted or modified according to the teachings of the present invention.

[0061] As described above, the present invention can be used to aggregate and drive magnetic micro-nanorobots, such as clusters composed of magnetic microparticles, micro magnetic control robots, and other magnetizable objects, enabling them to move to a specified target area without imaging guidance and aggregate. The aggregation position can be set and changed by adjusting the input signal of the electromagnetic coil. The present invention is particularly suitable for precise targeted therapy by delivering drugs or cells using micro-nanorobots in complex environments.

[0062] Compared with the prior art, the present invention has the following advantages:

[0063] (1) The present invention utilizes an electromagnetic coil to form a dynamic magnetic field. Only by adjusting the input current signal of the coil, it has significant convenience in the generation and adjustment process of the magnetic field.

[0064] (2) The present invention is based on the principle of generating an attraction zone at a specific position that can attract all magnetic objects. Therefore, the present invention can drive micro-clusters composed of different magnetic micro-nanorobots without considering the characteristics such as the size, shape, and material composition of individual robots, and does not depend on the distribution density of the robots. This is different from the traditional methods for controlling micro-nano clusters that require specific triggering mechanisms.

[0065] (3) By adjusting the input current of the coil, the present invention can drive the cluster to move precisely to different target positions. The micro-cluster is attracted by the magnetic force, so the process of moving from the initial position to the aggregation area is a spontaneous process. Therefore, this driving method is much easier than the existing micro-nano cluster control and does not depend on external navigation and image feedback.

[0066] (4) The method of the present invention can overcome many problems existing in traditional methods, such as maintaining mode stability, randomness of the initial distribution, and navigation in an unpredictable dynamic fluid environment.

[0067] The above advantages of the present invention have been experimentally demonstrated in different micro-group environments, including the open area environment in a chamber, the restricted environment in a microfluidic chip, and the ex vivo environment of a bovine eyeball with different micro-group agents.

[0068] The potential market of the present invention includes the medical science industry, especially in the fields of advanced biomedical devices and targeted drug therapy.

[0069] Although the present invention has been described in detail in combination with limited embodiments, it should be understood that the present invention is not limited to these disclosed embodiments. Those of ordinary skill in the art can conceive of other embodiments that conform to the spirit and scope of the present invention, including changes in the number of components, modifications, substitutions, or equivalent arrangements, and these embodiments all fall within the scope of the present invention.

Claims

1. A method for controlling a micro-nano robot swarm, wherein the micro-nano robots in the micro-nano robot swarm contain magnetic components, and the method for controlling the micro-nano robot swarm includes: Placing an object containing the micro-nano robot swarm in the working space of a magnetic field generating device, the magnetic field generating device including a plurality of electromagnetic coils; Providing input currents to the plurality of electromagnetic coils respectively to generate a gradient magnetic field in the working plane; Adjusting the input currents of the plurality of electromagnetic coils to rotate the gradient magnetic field; And Adjusting the position of the object in the working space and the rotation frequency of the gradient magnetic field to move and gather the micro-nano robots in the micro-nano robot swarm to a target position; Among them, the input current of each of the multiple electromagnetic coils is a sequential DC input electrical signal I·c i , the magnetic flux density of the gradient magnetic field is B(r,h), the rotation frequency of the gradient magnetic field is f, I is expressed as the maximum value of the input current, and the current of the i-th electromagnetic coil among the multiple electromagnetic coils is: Wherein, f and t respectively represent the rotation frequency and time period of the gradient magnetic field, The parameter ci is a correction coefficient, which belongs to an empirical value and is used to adjust the current of the i-th coil.

2. The micro-nano robot cluster control method according to claim 1, wherein, Adjusting the position of the micro-nano robot swarm by changing the timing function of the input currents of the plurality of electromagnetic coils.

3. The micro-nano robot cluster control method according to claim 1, wherein, The magnetic field gradient generated by the plurality of electromagnetic coils in the working space is greater than zero, and the gradient magnetic field is annularly distributed and based on the magnetic field distribution in the working plane.

4. The method for controlling a micro-nano robot cluster according to claim 1, wherein, Sequentially providing input currents to each of the plurality of electromagnetic coils to continuously rotate the magnetic field direction of the gradient magnetic field, and the rotation frequency of the gradient magnetic field is equal to the frequency of the input current.

5. The micro-nano robot swarm control method according to claim 4, wherein, Adjusting the input currents allocated to each of the plurality of electromagnetic coils by a microcontroller unit to change the rotation frequency of the gradient magnetic field.

6. The method for controlling a micro-nano robot cluster according to claim 1, wherein, When c1 = c2 = c3 = c4 = 1, the rotating magnetic field generates a centripetal force to attract the micro-nano robots to gather at the target position.

7. The micro-nano robot swarm control method according to claim 1, wherein, Changing the value of the parameter ci by a microcontroller unit.

8. The method for controlling a micro-nano robot cluster according to claim 7, wherein, When changing the value of the parameter ci, the target position is changed, and there is a definite mapping relationship between the value of the parameter ci and the target position.

9. The micro-nano robot swarm control method according to claim 8, wherein, It further includes creating a mapping relationship table, and the mapping relationship table is the relationship between the value of the parameter ci and the coordinates of the target position.

10. The method for controlling a micro-nano robot cluster according to claim 9, wherein, The mapping relationship is realized by solving the motion function through a backpropagation neural network.

11. The micro-nano robot cluster control method according to claim 1, wherein, The value of the parameter ci is adjusted in the following manner: First, the parameters ci of the electromagnetic coils on the same axis cannot be adjusted simultaneously. When adjusting one electromagnetic coil, the electromagnetic coil in the opposite direction of this electromagnetic coil should maintain the base value 1; Second, the change of the input current always increases. The parameter ci only increases from the base value 1, so the value of the parameter ci is always greater than or equal to 1.

12. The method for controlling a micro-nano robot cluster according to claim 1, wherein, Changing the height of the working plane in the gradient magnetic field by a lift, and observing the aggregation of the micro-nano robot swarm through an imaging device.

13. A micro-nano robot swarm control device, wherein the micro-nano robots in the micro-nano robot swarm contain magnetic components, and the control of the micro-nano robot swarm includes: A magnetic field generating device, the magnetic field generating device including a plurality of electromagnetic coils, and the plurality of electromagnetic coils are arranged in a ring in sequence; A driving device, the driving device being respectively connected to the plurality of electromagnetic coils; A microcontroller unit for controlling the driving device to generate a driving current; And The workbench is located at the center of the ring formed by the multiple electromagnetic coils and is used to place an object containing the micro-nano robot cluster; Wherein, the driving device generates a driving current to sequentially drive each of the multiple electromagnetic coils to generate a rotating magnetic field, and the rotating magnetic field is used to drive the micro-nano robot cluster to converge to a target position in the object; Among them, the input current of each of the multiple electromagnetic coils is a sequential DC input electrical signal I·c i , the magnetic flux density of the gradient magnetic field generated by the electromagnetic coil is B(r, h), the rotation frequency of the gradient magnetic field is f, I is expressed as the maximum value of the input current, and the current of the i-th electromagnetic coil among the multiple electromagnetic coils is: Wherein, f and t respectively represent the rotation frequency and time period of the gradient magnetic field, The parameter ci is a correction coefficient, which is an empirical value and is used to adjust the current of the i-th coil.

14. The micro-nano robot cluster control device according to claim 13, wherein, The multiple electromagnetic coils include three to twelve electromagnetic coils uniformly arranged in a ring.

15. The micro-nano robot cluster control device according to claim 14, wherein, The multiple electromagnetic coils include four orthogonal electromagnetic coils.

16. The micro-nano robot cluster control device according to claim 13, wherein, The microcontroller unit is used to change the value of the parameter ci, wherein the value of the parameter ci has a definite mapping relationship with the target position, and when the value of the parameter ci is changed, the target position is changed.

17. The micro-nano robot cluster control device according to claim 13, wherein, The workbench includes a lifting platform located in the central area of the multiple electromagnetic coils, and the height of the lifting platform relative to the multiple electromagnetic coils is adjustable and can be rotated to different directions.

18. The micro-nano robot cluster control device according to claim 13, further comprising an imaging device for imaging the object containing the micro-nano robot cluster to observe the position of the micro-nano robot cluster.

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