Chain cluster regulation and control and cargo transportation control method of magnetic drive micro-nano robot in air environment

Abstract

The invention relates to the technical field of micro-nano robots, in particular to a magnetically-driven micro-nano robot chain cluster regulation and cargo transportation control method suitable for an air environment. According to the chain cluster regulation and control method, a rotating magnetic field is formed in a vertical plane by applying a vertical cosine alternating magnetic field and a horizontal sine alternating magnetic field, the micro-nano robot is driven to gradually assemble a long chain cluster, and the length of the chain cluster can be dynamically regulated and controlled by adjusting the initial mass, the magnetic field frequency and the intensity. The cargo transportation control method comprises the following steps: applying a magnetic field formed by superimposing an xoy plane fan-shaped oscillating magnetic field and an alternate and reverse z-direction direct-current magnetic field, enabling a chain-shaped group to alternately swing in a conical surface and realize forward movement, and simultaneously applying a pushing force to cargoes, thereby realizing controllable transportation and displacement of the cargoes.

Description

Technical Field

[0001] The present invention relates to the field of micro-nano robot technology, and more specifically to a method for controlling chain clustering and cargo transportation of magnetically driven micro-nano robots in an air environment. Background Art

[0002] A micro-nano robot is a micro-nano actuator that can achieve precise movement and a variety of complex manipulation tasks in a confined space. Among the various driving methods of micro-nano robots, magnetic field drive has become a popular choice for researchers due to its long-range mobility, flexible controllability, biocompatibility, and strong driving ability. With the rapid development of micro-nano robot technology, single-body magnetically driven micro-nano robots are restricted by size and structure, have limited movement and control capabilities, and have poor driving force, which can no longer meet various application scenarios. Therefore, researchers have proposed a cluster collaboration strategy and designed various magnetically driven micro-nano robot clusters. These clusters have stronger movement capabilities and driving force, and at the same time have the unique feature of cluster-scale adaptive regulation, which can realize more complex multimodal collaborative operation tasks.

[0003] Currently, magnetically driven micro-nano robot clusters are limited by material properties, drive mechanisms, and environmental adaptability, and their research scope is still primarily limited to controllable drive in liquid media. Furthermore, in existing technologies, most micro-nano robot clusters rely on van der Waals forces, electrostatic forces, and hydrophobic / hydrophilic interactions between their surfaces and cargo to load and transport cargo. These methods are difficult to separate from the auxiliary effects of the liquid medium, and have limited load capacity and poor stability. Therefore, the present invention successfully develops a magnetically driven micro-nano robot chain cluster that can move in an air environment and achieve flexible control of cluster size. It also proposes a "swinging gait-like" cargo transportation control method. This method enables the magnetically driven micro-nano robot chain cluster to achieve flexible cargo propulsion, fully leveraging its structural advantage of a high thrust-to-weight ratio. It has broad application potential in the removal of foreign objects from the human respiratory tract and other complex scenarios requiring operation in an air environment. Summary of the Invention

[0004] The present invention aims to provide a method for controlling a chain of magnetic micro-nano robots in an air environment, enabling reconfigurable dynamic control of the cluster size of a chain of magnetically driven micro-nano robots. Furthermore, a "swinging gait-like" cargo transport control method is proposed, which can drive the chain of robots to synchronously and flexibly propel cargo while moving.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] A chain cluster control method based on magnetic micro-nano robots in an air environment includes the following steps:

[0007] S1: Apply a vertical cosine alternating magnetic field in the air environment, so that the micro-nano robots initially cluster in the vertical direction under the action of the magnetic field, forming multiple short chain-like clusters;

[0008] S2: Continue applying the horizontal sinusoidal alternating magnetic field, which is superimposed on the vertical cosine alternating magnetic field in step S1 to form a rotating magnetic field in the vertical plane;

[0009] S3: Under the action of a rotating magnetic field, the short chain-like cluster of micro-nano robots rolls horizontally and gradually assembles into a long chain-like cluster during the rolling process;

[0010] S4: By adjusting the total mass of the initial micro-nano robot, the frequency of the rotating magnetic field, and the magnetic field strength, the length of the magnetically driven micro-nano robot chain cluster can be dynamically controlled, thereby flexibly adapting to workspaces of different scales.

[0011] Furthermore, the alternating magnetic field used in S1 to S4 is generated by inputting a sine-cosine alternating voltage signal outputted by a signal control box into the three-dimensional Helmholtz coil.

[0012] Furthermore, the control box is powered by 220V AC. Through its internal power conversion, control, and drive components, it can output sinusoidal and cosine alternating voltage signals, as well as DC voltage signals, with a continuously adjustable frequency between 0 and 500Hz and a continuously adjustable voltage amplitude between 0 and 44V. It connects to the three-dimensional Helmholtz coil via a specific interface to precisely control magnetic field characteristic parameters such as frequency and intensity. The power conversion component comprises a switching power supply and a voltage regulator module; the control component comprises an STM32 microcontroller, a PS2 controller, and a controller signal receiver; and the drive component comprises a motor driver board, or servo drive.

[0013] Furthermore, the magnetic micro-nano robot is a large-size ferroferric oxide particle in the range of 10 μm to 30 μm, and most of them are polyhedral structures with extremely irregular shapes.

[0014] A method for controlling the "swinging gait-like" cargo transportation of a chain-like cluster of magnetically driven micro-nano robots in an air environment. Under this control method, the chain-like cluster of micro-nano robots always maintains a local "point contact" state between one of its two ends and the base during movement, and enables the entire chain-like cluster to swing alternately left and right within a conical surface. When the swinging direction switches, the chain-like cluster synchronously switches the end in contact with the base, thereby continuously moving forward while swinging back and forth, forming a "swinging gait-like" motion pattern. Furthermore, during the swinging process of the chain-like cluster, an effective driving force can be applied to the surrounding cargo, thereby achieving controllable transportation and displacement of the cargo.

[0015] Further, the magnetic field working mode of the regulation method is composed of a fan-shaped oscillating magnetic field component in the xoy plane and a z-direction direct current magnetic field component superimposed; wherein, is used to drive the chain-like population to swing left and right alternately, is used to lift one end of the chain-like population, and when swinging to the extreme position in the same direction for a single time, by changing the direction, the switching of the contact end of the chain-like population with the substrate is realized.

[0016] Further, the fan-shaped oscillating magnetic field component in the xoy plane is formed by superimposing an x-direction cosine alternating magnetic field and a y-direction sine alternating magnetic field; within a complete swing period, by adjusting the angular frequency and phase components of the x-direction and y-direction alternating magnetic fields when swinging to the extreme position in the same direction for a single time, the switching of the swinging direction of the chain-like population is realized.

[0017] Further, by adjusting the field strength ratio of the fan-shaped oscillating magnetic field component in the xoy plane and the z-direction direct current magnetic field component , the pitching angle between the chain-like population and the horizontal plane can be controlled; the traveling direction and the maximum swing amplitude of the chain-like population are jointly determined by the phase components of the x-direction and y-direction alternating magnetic fields; by adjusting the pitching angle between the chain-like population and the horizontal plane, the regulation of the length of the chain-like population can also be realized to adapt to working spaces of different scales.

[0018] A method for removing foreign objects in the respiratory tract by a chain-like population includes the following steps:

[0019] S1: Release magnetic micro-nanorobots to the main area of the simulated tracheal channel through a bronchoscope;

[0020] S2: Apply a rotating magnetic field to cluster the magnetic micro-nanorobots into a chain-like population and move them to the target branch blind end area where the glass beads are located;

[0021] S3: After all the chain-like population reaches the target area, switch the rotating magnetic field to the "swinging gait-like" magnetic field mode and control the chain-like population to return along the original path;

[0022] S4: During the return process, the chain-like population synchronously pushes the glass beads towards the main area, and finally removes the foreign objects from the branch area, realizing the removal of the simulated respiratory tract foreign objects.

[0023] The beneficial effects of the present invention are:

[0024] By applying a combined magnetic field in an air environment, a chain-like population of magnetically driven micro-nano robots capable of achieving stable assembly and controllable movement in the air environment is developed, and a flexible regulation method for the cluster scale of the chain-like population is proposed. At the same time, a "swinging gait imitation" cargo transportation control method based on the chain-like population of magnetically driven micro-nano robots is proposed, which can synchronously realize the pushing transportation of goods during the movement of the chain-like population and adapt to the cargo transportation needs in working spaces of different scales. Compared with traditional micro-nano robot populations, the present invention overcomes the technical bottlenecks of existing micro-nano robot populations highly relying on liquid media, limited cargo transportation capabilities, and difficulty in achieving stable movement and manipulation in the air environment, and demonstrates excellent application prospects and practical values in the removal of foreign bodies in the human respiratory tract and other complex scenarios that require operation in the air environment. Description of the Drawings

[0025] The present invention will be further described in detail below in conjunction with the drawings and specific implementation methods.

[0026] Figure 1 It is an overall schematic diagram of micro-nano robots clustering into a chain-like population and transporting goods in an air environment;

[0027] Figure 2 It is a scanning electron microscope image and a hysteresis loop diagram of a micro-nano robot;

[0028] Figure 3 It is a schematic diagram and a time-sequence snapshot diagram of micro-nano robots clustering into a chain-like population in an air environment;

[0029] Figure 4 It is a data diagram of the change in the length of the chain-like population of micro-nano robots under different masses and magnetic field parameters;

[0030] Figure 5 It is a schematic diagram of the "swinging gait imitation" motion mode of the chain-like population of magnetically driven micro-nano robots moving along the positive x direction, its magnetic field working mechanism diagram, and a time-sequence snapshot diagram;

[0031] Figure 6 It is a schematic diagram of the pitch angle of the chain-like population of magnetically driven micro-nano robots and a data diagram of the change in the length of the population under different pitch angle conditions;

[0032] Figure 7 It is a time-sequence snapshot diagram of the cargo transportation trajectory of the chain-like population of magnetically driven micro-nano robots and a mechanical analysis diagram between the cargo and the population;

[0033] Figure 8 It is a time-sequence snapshot diagram for verifying the flexibility of cargo transportation of the chain-like population of magnetically driven micro-nano robots and a time-sequence snapshot diagram for verifying its transportation ability in a narrow pipeline;

[0034] Figure 9It is a time - series snapshot of a chain - like swarm of magnetically - driven micro - nano robots clearing foreign objects in a simulated tracheal channel. Detailed implementation mode

[0035] The present invention will be further described in detail below with reference to the accompanying drawings.

[0036] The scanning electron microscope image of the magnetic micro - nano robot is as Figure 2 from A to Figure 2 B shown. It is a magnetite particle with an irregular polyhedron structure, and the particle size is in the range of 10μm - 30μm. As can be seen from Figure 2 C, it has a high saturation magnetization intensity of 64.09 emu / g, showing excellent magnetic properties. Since the present invention does not involve the analysis of the shape effect of the magnetic micro - nano robot, its specific shape is not the focus of the present invention. For the convenience of demonstrating the chain - like swarm regulation and cargo transportation control method of the magnetic micro - nano robot, all schematic diagrams in the specification intuitively represent the magnetic micro - nano robot with a spherical structure.

[0037] As Figure 1 shown, the present invention successfully realizes the chain - like swarm assembly of magnetic micro - nano robots by applying a rotating magnetic field in the vertical plane in an air environment. Further, for the chain - like swarm, a "swinging gait - like" cargo transportation control method is proposed, so that it can synchronously apply a driving force to the front - end cargo during the movement process, thereby realizing the flexible transportation of the cargo.

[0038] A detailed description of a chain - like swarm regulation method for magnetic micro - nano robots based on an air environment is as follows:

[0039] As Figure 3 shown, first, a cosine alternating voltage signal is applied to the z - direction coil of the three - dimensional Helmholtz coil device to generate a cosine alternating magnetic field in the vertical direction, driving the magnetic micro - nano robots to preliminarily swarm in the vertical direction under the influence of the magnetic dipole interaction force in the air environment, forming multiple short - chain - like swarms. Subsequently, a sine alternating voltage signal is applied to the x - direction coil to further generate a sine alternating magnetic field in the horizontal direction, which is coupled with the z - direction magnetic field to form a rotating magnetic field rotating clockwise in the vertical plane. Under the action of the rotating magnetic field, the short - chain - like swarms are driven by the magnetic torque to roll in the horizontal direction and gradually assemble into a long - chain - like swarm during the movement process due to the magnetic mutual attraction between them until the swarm scale tends to be stable.

[0040] Further, the length of the chain - like swarm is controlled by changing the initial mass m of the magnetic micro - nano robot, the frequency f and the field strength B of the rotating magnetic field to flexibly adapt to working spaces of different scales.

[0041] As Figure 4As shown in Figure A, under the conditions of magnetic field strength B = 15 mT and frequency f = 1 Hz, the average length of the chain-like aggregate increases with the increase of the initial mass m of the magnetic micro-nanorobot. As the curve flattens out, it can be seen that the influence of the initial mass m on the aggregate length gradually weakens. This is attributed to the fact that the rotating magnetic field strength B and frequency f limit the assembly ability of the aggregate, making the aggregation ability of the magnetic micro-nanorobot tend to saturate in a specific cluster region.

[0042] As Figure 4 shown in Figure B, under the conditions of magnetic field strength B = 15 mT and initial mass m = 3 mg, the average length of the chain-like aggregate decreases with the increase of the rotating magnetic field frequency f. At an extremely low magnetic field frequency of 0.1 Hz, the average length of the chain-like aggregate can reach 4.31 mm, while it is only 1.04 mm at 60 Hz. This phenomenon is due to the intensification of the centrifugal force between magnetic micro-nanorobots at high frequencies, resulting in a decrease in the stability of the original long-chain structure, separation, and shortening.

[0043] As Figure 4 shown in Figure C, under the conditions of magnetic field frequency f = 1 Hz and initial mass m = 3 mg, the average length of the chain-like aggregate increases with the increase of the rotating magnetic field strength B. This is because the high magnetic field strength enhances the magnetic mutual attraction between short chains, promoting their assembly into long-chain structures.

[0044] Furthermore, a detailed description is given to a "swinging gait-like" cargo transportation control method based on a chain-like aggregate of magnetically driven micro-nanorobots:

[0045] Taking the case where the chain-like aggregate of magnetically driven micro-nanorobots travels along the positive x direction as an example, combined with Figure 5 to illustrate the control method. As Figure 5 shown in Figures B and Figure 5 C, the magnetic field mode of the control method is composed of a sector-shaped oscillating magnetic field component in the xoy plane and a z-direction direct current magnetic field component superposed. Specifically, the motion behavior and magnetic field working mechanism of the chain-like aggregate traveling along the positive x direction under the control method can be decomposed into the following steps:

[0046] S1: In the initial state, the sector-shaped oscillating magnetic field component in the xoy plane and the z-direction direct current magnetic field component together constitute the total oblique magnetic field vector in the three-dimensional Cartesian coordinate system. The chain-like aggregate tilts up at one end under the action of the magnetic torque and tends to align with the direction of this total magnetic field vector. Subsequently, rotates counterclockwise around the origin, causing the chain-like aggregate to swing counterclockwise around its contact point with the substrate within a conical surface, corresponding to steps ① and ② in the figure;

[0047] S2: After the chain-like aggregate swings counterclockwise to the extreme position, control the z-direction DC magnetic field component to instantaneously reverse, so that under the action of the instantaneous magnetic torque, the contact end with the substrate is switched. Due to the change of the landing position, the whole chain-like aggregate moves forward, corresponding to step ③ in the figure;

[0048] S3: Control the rotation direction to switch from counterclockwise to clockwise, and the chain-like aggregate continues to swing clockwise around its contact point with the substrate under the action of the magnetic torque, corresponding to steps ④ and ⑤ in the figure;

[0049] S4: After the chain-like aggregate swings clockwise to the extreme position, control the z-direction DC magnetic field component to instantaneously reverse, realizing the switching of the contact end of the aggregate with the substrate, corresponding to step ⑥ in the figure. At the same time, the rotation direction is switched again, repeating the above cycle process.

[0050] Since the chain-like aggregate continuously makes a conical swing during the traveling process, always maintaining an inclined posture with one end tilted up and one end in contact with the substrate, and the switching mode of its contact end is similar to the bipedal alternating process in human walking, the described control method is called the "swinging gait imitation" cargo transportation control method, as Figure 5 shown in A.

[0051] As Figure 5 shown in B, define the angle between the magnetic field component at its rotation limit position and the center line of its fan-shaped oscillation region as the swing angle α, then the maximum swing angle of the chain-like aggregate in a single direction is 2α. Further, define the angle between the center line of the fan-shaped oscillation region and the positive x-axis as the traveling angle θ, which determines the traveling direction of the chain-like aggregate. Taking the Figure 5 shown situation as an example, when the traveling angle θ = 3π / 2, the chain-like aggregate travels along the positive x-direction, that is, the angle between its traveling direction and the positive x-axis always has a phase difference of 3π / 2 with the traveling angle θ. The magnetic field working mechanism of the described control method can be written in the following mathematical expression form:

[0052]

[0053] where T is the time for the chain-like aggregate to complete a full reciprocating swing once, that is, the swing period; t is the working time of the magnetic field; B xy is the magnetic field intensity modulus of the xoy plane fan-shaped oscillating magnetic field component ; B z is the magnetic field intensity modulus of the z-direction DC magnetic field component ; f is the rotation frequency, that is, the magnetic field frequency; B is the total magnetic field vector The magnitude of the magnetic field strength, i.e., the magnetic field strength; and respectively represent the unit vectors in the positive x, y, and z directions; is formed by superimposing a cosine alternating magnetic field in the x direction and a sine alternating magnetic field in the y direction By adjusting the angular frequencies and phase components of the alternating magnetic fields in the x and y directions it is possible to achieve the switching of the rotation direction. Further, by adjusting the value of the traveling angle θ in

[0054] In addition, define the total magnetic field vector and the angle between the xoy plane as the pitch angle β, as shown in Figure 6 A. From the experimental results, by adjusting the value of the pitch angle β, it is also possible to control the length of the chain-like aggregate to adapt to working spaces of different scales. As shown in Figure 6 B, under the conditions of an initial mass m = 3 mg, a magnetic field strength B = 15 mT, a magnetic field frequency f = 1 Hz, and a swing angle α = 45°, the average length of the chain-like aggregate decreases with the increase of the pitch angle β. This may be because the increase in the pitch angle β leads to an increase in the instantaneous angular acceleration during the switching of the contact end of the chain-like aggregate with the substrate, thereby intensifying the instantaneous centrifugal force between the micro-nano robots and destroying the stability of the original long-chain structure, resulting in its separation and shortening.

[0055] Further, the chain-like aggregate can exert an effective driving force on the surrounding goods during the swinging process, thereby realizing the controllable transportation and displacement of the goods. Using a glass bead with a diameter of 1 mm as the goods, analyze the driving and transportation effects of the chain-like aggregate on the goods. From Figure 7 A of the experimental results, the movement trajectory of the glass bead under the push of the chain-like aggregate is wavy rather than straight. This is because the chain-like aggregate exerts a driving force on the glass bead during the swinging process and its swinging direction continuously changes. As shown in Figure 7 B, the forces acting on the glass bead include the normal collision force Fn and the tangential force Ft exerted by the chain-like aggregate, the frictional force Ff and the supporting force Fs provided by the substrate, and the gravitational force G. At the same time, the tangential force will also generate a tangential torque M relative to the centroid of the glass bead, driving it to rotate.

[0056] Verify the flexibility of the goods transportation of the chain-like aggregate. As shown in Figure 8 A, the chain-like aggregate can transport a glass bead with a diameter of 1 mm from the starting area in the lower left corner of the maze channel to the target area in the lower right corner within a short time, and has the ability to transport goods along paths such as "direct turning" and "U-shaped continuous turning". Further, verify the goods transportation ability of the chain-like aggregate in extremely narrow channels. AsFigure 8 As shown in B, under the specific parameter conditions of magnetic field strength B = 12 mT, magnetic field frequency f = 0.4 Hz, swing angle α = 69°, and pitch angle β = 12°, the chain-like aggregate can effectively transport glass beads with a diameter of 1 mm in a pipe with a diameter of 3 mm.

[0057] Furthermore, to verify the ability of the chain-like aggregate to remove foreign objects in a simulated tracheal channel, as Figure 9 shown. The foreign object is a glass bead with a diameter of 1 mm, and the simulated tracheal channel is a 3D printed model constructed based on human segmental bronchus CT scan data. To ensure the experimental effect, the outlets of the channel are sealed. Specifically, the method for the chain-like aggregate to remove respiratory foreign objects includes the following steps:

[0058] S1: Release the magnetic micro-nanorobots into the main area of the simulated tracheal channel through a bronchoscope;

[0059] S2: Apply a rotating magnetic field to cluster the magnetic micro-nanorobots into a chain-like aggregate and move it to the target branch blind end area where the glass bead is located;

[0060] S3: After all the chain-like aggregate reaches the target area, switch the rotating magnetic field to the "swinging gait-like" magnetic field mode and control the chain-like aggregate to return along the original path;

[0061] S4: During the return process, the chain-like aggregate synchronously pushes the glass bead towards the main area, and finally removes the foreign object from the branch area, realizing the removal of the simulated respiratory foreign object.

[0062] Among them, in step S2, a rotating magnetic field is used instead of the "swinging gait-like" magnetic field mode because the disturbance of the chain-like aggregate to the glass bead under the rotating magnetic field is extremely small, which can effectively prevent the glass bead from being pushed deeper into the blind end, thus ensuring the subsequent smooth removal of the glass bead.

[0063] In summary, the present invention develops a chain-like aggregate of magnetically driven micro-nanorobots suitable for an air environment, and further proposes a method for regulating the cluster scale of the aggregate and a "swinging gait-like" cargo transportation control method for the aggregate. Among them, the "swinging gait-like" cargo transportation control method can enable the chain-like aggregate to synchronously push the target cargo during the traveling process, thereby realizing the controllable transportation of the cargo. In addition, by adjusting the initial total mass m, magnetic field frequency f, magnetic field strength B, and pitch angle β of the micro-nanorobots, not only can the dynamic regulation of the length of the chain-like aggregate be realized, but also the contact effect between it and the cargo can be adjusted, so as to meet the cargo transportation requirements in different scale spaces. The present invention has broad application prospects in the removal of human respiratory foreign objects and other complex scenarios that require operation in an air environment.

Claims

1. A method for regulating the chain-like aggregation of magnetic micro-nano robots in an air environment, characterized in that, It includes the following steps: S1: Apply a vertically - directed cosine alternating magnetic field in an air environment, so that the micro - nano robots are initially clustered in the vertical direction under the action of the magnetic field, forming multiple short - chain - like aggregates; S2: Continuously apply a horizontally - directed sine alternating magnetic field, which is superimposed on the vertically - directed cosine alternating magnetic field in step S1 to form a rotating magnetic field in the vertical plane; S3: Under the action of the rotating magnetic field, the short - chain - like aggregates of micro - nano robots roll in the horizontal direction and are gradually assembled into long - chain - like aggregates during the rolling process; S4: By adjusting the total mass of the initial micro - nano robots, the frequency and magnetic field intensity of the rotating magnetic field, the dynamic regulation of the length of the chain - like aggregates of magnetically - driven micro - nano robots is realized, so as to flexibly adapt to working spaces of different scales.

2. The chain-like cluster regulation method of a magnetic micro-nano robot based on an air environment according to claim 1, characterized in that: The alternating magnetic fields used in S1 - S4 are generated by passing a sine - cosine alternating voltage signal output by a signal control box into a three - dimensional Helmholtz coil.

3. The chain-like cluster regulation method of a magnetic micro-nano robot based on an air environment according to claim 2, characterized in that: The control box is powered by 220V alternating current. Through the internal power conversion component, control component and drive component, it can output a sine - cosine alternating voltage signal and a direct - current voltage signal with a continuously adjustable frequency in the range of 0 to 500Hz and a continuously adjustable voltage amplitude between 0 and 44V, and is connected to the three - dimensional Helmholtz coil through a specific interface to achieve precise regulation of magnetic field characteristic parameters such as magnetic field frequency and magnetic field intensity.

4. A method for regulating a chain-like cluster of magnetic micro-nanorobots in an air environment according to claim 3, characterized in that: The magnetic micro - nano robots are large - particle - size iron oxide particles in the range of 10μm - 30μm, mostly polyhedral structures with extremely irregular shapes.

5. A method for controlling the cargo transportation of a magnetically driven micro-nano robot in an air environment, characterized in that, The motion behavior of the chain - like aggregates moving along the positive x - direction under this control method and its corresponding magnetic field working mechanism include the following steps: S1: In the initial state, the xoy plane sector oscillating magnetic field component and the z-direction DC magnetic field component together form the total oblique magnetic field vector in the three-dimensional Cartesian coordinate system The chain-like aggregate tilts up at one end under the action of the magnetic torque and tends to align with the direction of the total magnetic field vector; subsequently, it rotates counterclockwise around the origin, causing the chain-like aggregate to swing counterclockwise around its contact point with the substrate within a conical surface; S2: After the chain-like aggregate swings to the extreme position in the counterclockwise direction, control the z-direction DC magnetic field component to reverse instantaneously, so that its contact end with the substrate is switched under the action of the instantaneous magnetic torque; due to the change in the landing position, the overall chain-like aggregate moves forward; S3: Control The rotation direction of is switched from counterclockwise to clockwise, and the chain-like population continues to swing clockwise around its contact point with the substrate under the action of magnetic torque; S4: After the chain-like population swings clockwise to the extreme position, control the z-direction DC magnetic field component to reverse instantaneously, realizing the switching of the contact end of the population and the substrate. At the same time, the rotation direction switches again, repeating the above cycle process.

6. The cargo transportation control method of a magnetically driven micro-nano robot in an air environment according to claim 5, characterized in that: During the swinging process of the chain - like aggregates, an effective driving force is applied to the surrounding goods to achieve the controllable transportation and displacement of the goods.

7. A method for controlling the cargo transportation of a magnetically driven micro-nano robot in an air environment according to claim 5, characterized in that: Sector oscillating magnetic field component in the xoy plane It is formed by the superposition of a cosine alternating magnetic field in the x direction and a sine alternating magnetic field in the y direction; within a complete swing period, by adjusting the angular frequency and phase components of the alternating magnetic fields in the x and y directions when swinging to the extreme position in the same direction once, the switching of the swinging direction of the chain-like population is realized.

8. A method for controlling the cargo transportation of a magnetically driven micro-nano robot in an air environment according to claim 5, characterized in that: By adjusting the field strength ratio of the sector oscillating magnetic field component in the xoy plane and the DC magnetic field component in the z direction the pitching angle between the chain-like aggregate and the horizontal plane can be controlled; the traveling direction and the maximum swing amplitude of the chain-like aggregate are jointly determined by the phase components of the alternating magnetic fields in the x and y directions.

9. A method for controlling the cargo transportation of a magnetically driven micro-nano robot in an air environment according to claim 8, characterized in that: By adjusting the pitch angle between the chain - like aggregates and the horizontal plane, the regulation of the length of the chain - like aggregates can also be realized to adapt to working spaces of different scales.

10. A method for removing foreign bodies from the respiratory tract by a chain-like colony, characterized in that, It includes the following steps: S1: Release the magnetic micro - nano robots to the main area of the simulated tracheal channel through a bronchoscope; S2: Apply a rotating magnetic field to cluster the magnetic micro - nano robots into a chain - like aggregate and move it to the target branch blind - end area where the glass beads are located; S3: After all the chain - like aggregates reach the target area, switch the rotating magnetic field to the "swinging - like gait" magnetic field mode and control the chain - like aggregates to return along the original path; S4: During the return process, the chain - like aggregates synchronously push the glass beads towards the main area, and finally remove the foreign body from the branch area to achieve the removal of the simulated respiratory tract foreign body.

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