CN115020065B - Online magnetization system and magnetization method for micro-robot - Google Patents

Abstract

The invention discloses an online magnetization system and a magnetization method for micro-robots. The online magnetization system includes: a three-axis Helmholtz coil (1), a working platform (2), and a pair of magnetization coils (3 ); the center of the upper surface of the working platform (2) has an axial magnetization groove (2-1) and a radial magnetization groove (2-2), and the axial magnetization groove (2-1) and the radial magnetization groove (2-1) The slots (2-2) are rectangular; the pair of magnetized coils (3) comprises a first magnetized coil (3-1) and a second magnetized coil (3-2), and the first magnetized coil (3-1) and the second magnetizing coil (3-2) are all parallel to the short side of the working platform (2); on the Mholtz coil (1).

Description

An online magnetization system and magnetization method for micro-robots

technical field

The invention relates to the technical field of micro-nano operation, in particular to an online magnetization system and a magnetization method for a micro-robot.

Background technique

With the development of material science and control theory, the characteristic size and operation precision of robots have entered the micro-nano level. Microrobots capable of telemanipulating small objects have been of great interest, especially for single-cell research, microassembly, and drug delivery. However, it is difficult to achieve precise, fast and flexible operations with traditional operating techniques.

In recent years, advances in remote actuation and control technologies have facilitated the development of untethered microrobots that can move autonomously and interact with their environment. In general, tetherless mobile microrobots are driven by local chemical reactions and external physical field stimuli, such as electric fields, light fields, magnetic fields, and sound waves.

At present, magnetic field-driven micro-robots have been extensively studied due to their advantages of non-contact, programmability, integrability, and harmlessness to the human body. For magnetically actuated microrobots, different magnetic moments lead to different deformations and motions. However, the existing magnetically actuated microrobots have a constant magnetic moment throughout the experiment, which makes the microrobots move in a single mode and limits the multimodal motion of the microrobots. A commonly used method to change the magnetization direction of a magnetically driven micro-robot is to place the micro-robot into an external strong magnetic field for magnetization and then put it into the corresponding electromagnetic drive system to generate a certain mode of motion by controlling the electromagnetic drive magnetic field. But this way is not suitable for continuous operation, and wastes time.

In order to solve the single motion mode of the microrobot, it is necessary to develop a magnetic drive system that can change the magnetic moment of the microrobot online.

Contents of the invention

In view of this, the present invention provides an online magnetization system and magnetization method for micro-robots, which can solve the problem that the movement mode of the micro-robot is single, and when it is necessary to change the magnetization direction in order to adjust the movement mode of the micro-robot, it is necessary to repeatedly move the micro-robot from Technical issues taken in magnetic drive systems.

In order to solve the above-mentioned technical problems, the present invention is achieved in this way.

An online magnetization system for microrobots, comprising:

Three-axis Helmholtz coil, working platform, magnetizing coil pair;

The working platform is a cuboid device placed horizontally, and the center of the upper surface of the working platform has an axial magnetization groove and a radial magnetization groove, and the axial magnetization groove and the radial magnetization groove are rectangular; the shaft The magnetization grooves are parallel to the long sides of the working platform, the radial magnetization grooves are parallel to the short sides of the working platform, the axial magnetization grooves are perpendicular to the radial magnetization grooves, and the gap between the two grooves is The distance is 1mm;

The pair of magnetized coils includes a first magnetized coil and a second magnetized coil, the openings of the first magnetized coil and the second magnetized coil are parallel to the short side of the working platform, and the first magnetized coil is arranged on the One short edge of the upper surface of the working platform, the second magnetizing coil is disposed on the other short edge of the upper surface of the working platform;

The working platform and the pair of magnetizing coils are built on the three-axis Helmholtz coil;

The online magnetization refers to the ability to change the direction of the magnetic moment of the robot at any time during operation.

Preferably, the online magnetization system has a control interface for receiving control instructions from the control module, the control instructions include instructions for controlling Helmholtz coils and/or magnetizing coil pairs, and controlling the Helmholtz coils for A uniform rotating magnetic field is generated, and the pair of magnetizing coils is controlled to generate a strong magnetic field for magnetization.

Preferably, the axial magnetization groove and the radial magnetization groove are located at one end of the protrusion of the working platform.

Preferably, the axial magnetization groove and the radial magnetization groove are both rectangular, with a length of 1.5 mm and a diameter of 500 μm.

Preferably, the direction and frequency of the magnetic field generated by the three-axis Helmholtz coil are adjusted by a single-chip microcomputer to control the micro-robot to enter the corresponding magnetization slot, and then send an attenuated sinusoidal signal to the pair of magnetization coils to make the micro-robot The robot is demagnetized, and finally the magnetization direction of the micro robot is changed by the strong magnetic field generated by the magnetization coil pair.

An online magnetization method for micro-robots, using the above-mentioned online magnetization system, the online magnetization method includes the following steps:

Step S1: Receive a control command based on the control interface, the control command indicates the magnetization direction of the micro robot; if the control command is received, enter step S2; otherwise, the method ends;

Step S2: Obtain the initial magnetization direction of the micro-robot, the initial magnetization direction includes axial or radial, the axial direction is parallel to the long side of the working platform, and the radial direction is parallel to the working platform The short side of the platform 2; the movement of the micro-robot is controlled by the three-axis Helmholtz coil, so that the micro-robot can move in any direction on the work platform, and at this time, the magnetizing coil is powered off; If the initial magnetization direction is along the axial direction, enter step S3; if the initial magnetization direction is along the radial direction, enter step S4;

Step S3: Control the direction of the rotating magnetic field generated by the three-axis Helmholtz coil, make the micro robot enter the axial magnetization groove, and energize the magnetization coil pair, and the decreasing magnetic field and strong magnetic field respectively generated by the magnetization coil pair The magnetic field demagnetizes and re-magnetizes the micro-robot; after the magnetization is completed, the direction of the rotating magnetic field is changed, and the micro-robot is moved out of the axial magnetization slot; after the micro-robot is used, the micro-robot is Demagnetization operation, enter step S1;

Step S4: Adjust the frequency and direction of the magnetic field generated by the three-axis Helmholtz coil, make the micro-robot enter the radial magnetization slot, and energize the magnetized coil pair, the decreasing magnetic field and strong magnetic field generated by the magnetized coil pair Degaussing and re-magnetizing the micro-robot respectively; after the magnetization ends, changing the direction of the rotating magnetic field, and moving the micro-robot out of the radial magnetization slot; after using the micro-robot, performing For demagnetization operation, go to step S1.

Beneficial effect:

The present invention takes the miniature columnar robot as an example, and the columnar robot is manufactured with PDMS and NdFeB particles, which ensures that the columnar robot is ferromagnetic. NdFeB has a high coercive force, and can maintain a high residual magnetization in an external magnetic field after magnetization, and needs to be demagnetized before re-magnetization. The robot can perform different operations before and after magnetization.

The present invention provides an online magnetization system and method for micro-robots, by installing a pair of magnetization coils in the Y-axis direction of the three-axis Helmholtz coil, and two The magnetization groove is designed on the side, and then the columnar robot is controlled to enter the corresponding magnetization groove for demagnetization and re-magnetization. Magnetized robots can perform different actions.

It has the following technical effects:

(1) The structure of the online magnetization system provided by the present invention is simple. Based on the original magnetic drive system based on Helmholtz coils, it can reduce the need to repeatedly take the columnar robot from the magnetic drive device during the process of changing the magnetization direction. It has the advantages of convenience and easy operation.

(2) The online magnetization method provided by the present invention is easy to operate.

(3) The present invention provides at least two mutually switchable magnetization directions, which can realize the multi-modal movement of the micro-robot.

Description of drawings

Fig. 1 is a structural schematic diagram of an online magnetization system for a micro robot provided by the present invention.

Fig. 2 is a schematic structural view of the working platform for the online magnetization system of the micro-robot provided by the present invention.

Fig. 3 is a schematic diagram of the magnetization process of the magnetic medium provided by the present invention.

Fig. 4 is a schematic diagram of the movement of the micro-robot with a vertical axis direction provided by the present invention.

Fig. 5 is a schematic diagram of the movement of the micro-robot with an axis direction provided by the present invention.

Fig. 6(A) is a schematic diagram of the axially magnetized robot moving to the magnetized slot provided by the present invention.

Fig. 6(B) is a schematic diagram of the robot rotating cells provided by the present invention.

Fig. 7 is a schematic diagram of axial magnetization provided by the present invention.

Reference signs:

1: Three-axis Helmholtz coil, 2: Working platform, 3: Magnetizing coil pair, 1-1: Y-axis Helmholtz coil, 1-2: X-axis Helmholtz coil, 1-3: Z Axial Helmholtz coil, 2-1: axial magnetization slot, 2-2: radial magnetization slot, 3-1: first magnetization coil, 3-2: second magnetization coil.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1-Figure 2 and Figure 6, the present invention proposes an online magnetization system for micro-robots, including:

Three-axis Helmholtz coil 1, working platform 2, magnetizing coil pair 3.

The working platform 2 is a horizontal cuboid device, the center of the upper surface of the working platform 2 has an axial magnetization groove 2-1 and a radial magnetization groove 2-2, and the axial magnetization groove 2-1 and The radial magnetization grooves 2-2 are rectangular; the axial magnetization grooves 2-1 are parallel to the long sides of the working platform 2, and the radial magnetization grooves 2-2 are parallel to the short sides of the working platform 2 , the axial magnetization groove 2-1 is perpendicular to the radial magnetization groove 2-2, and the distance between the two grooves is 1 mm;

The pair of magnetized coils 3 includes a first magnetized coil 3-1 and a second magnetized coil 3-2, and the openings of the first magnetized coil 3-1 and the second magnetized coil 3-2 are all connected to the working platform 2 The short sides are parallel, the first magnetizing coil 3-1 is arranged on a short side edge of the upper surface of the working platform 2, and the second magnetizing coil 3-2 is arranged on the upper surface of the working platform 2 the other short edge;

The working platform 2 and the pair of magnetizing coils 3 are built on the three-axis Helmholtz coil 1;

The online magnetization refers to the ability to change the direction of the magnetic moment of the robot at any time during operation.

Optionally, the axial magnetization groove 2-1 and the radial magnetization groove 2-2 are located at the protruding end of the working platform 2, thereby ensuring the integrity of the working space on the working platform 2 and reducing the impact of the magnetizing coil on the control system. intrusive. The three-axis Helmholtz coil 1 includes a Y-axis Helmholtz coil 1-1, an X-axis Helmholtz coil 1-2, and a Z-axis Helmholtz coil 1-3.

Optionally, the magnetization groove can also be designed in other positions of the working platform according to requirements.

In this embodiment, the micro-robot is a columnar robot. Both the axial magnetization groove 2-1 and the radial magnetization groove 2-2 are rectangular, with a length of 1.5 mm and a diameter of 500 μm.

Further, the online magnetization system has a control interface for receiving control instructions from the control module, the control instructions include instructions for controlling Helmholtz coils and/or magnetization coil pairs, and controlling the Helmholtz coils for A uniform rotating magnetic field is generated, and the pair of magnetizing coils is controlled to generate a strong magnetic field for magnetization. Adjust the direction and frequency of the magnetic field generated by the three-axis Helmholtz coil through the single-chip microcomputer, control the micro-robot to enter the corresponding magnetization slot, and then send an attenuated sinusoidal signal to the magnetization coil pair to demagnetize the micro-robot, Finally, the magnetization direction of the microrobot is changed by the strong magnetic field generated by the magnetization coil pair.

As shown in Figures 3-5, the present invention proposes an online magnetization method for micro-robots, using the above-mentioned online magnetization system, and the online magnetization method includes the following steps:

Step S1: Receive a control command based on the control interface, the control command indicates the magnetization direction of the micro robot; if the control command is received, enter step S2; otherwise, the method ends;

Step S2: Obtain the initial magnetization direction of the micro-robot, the initial magnetization direction includes axial or radial, the axial direction is parallel to the long side of the working platform, and the radial direction is parallel to the working platform The short side of the platform 2; the movement of the micro-robot is controlled by the three-axis Helmholtz coil, so that the micro-robot can move in any direction on the work platform, and at this time, the magnetizing coil is powered off; If the initial magnetization direction is along the axial direction, enter step S3; if the initial magnetization direction is along the radial direction, enter step S4;

Step S3: Controlling the direction of the rotating magnetic field generated by the three-axis Helmholtz coil, making the micro-robot enter the axial magnetization slot, and energizing the magnetization coil pair, the decreasing magnetic field and the strong magnetic field generated by the magnetization coil pair Degaussing and re-magnetizing the micro-robot respectively; after magnetization, changing the direction of the rotating magnetic field, moving the micro-robot out of the axial magnetization slot; after using the micro-robot, performing Demagnetization operation, enter step S1;

In this embodiment, when the initial magnetization direction of the micro-robot is in the radial direction, the direction of the rotating magnetic field is controlled, and the micro-robot mainly forms a movement mode of rolling or standing on the interface of the working platform to rotate around the Z axis, as shown in Figure 4 shown. The micro-robot can be controlled to roll or stand upright and then fall down into the axial magnetization groove through a rotating magnetic field; after magnetization is completed, a rotating magnetic field along the X-axis is applied to make the micro-robot roll out of the axial magnetization groove.

Step S4: Adjust the frequency and direction of the magnetic field generated by the three-axis Helmholtz coil, make the micro-robot enter the radial magnetization slot, and energize the magnetized coil pair, the decreasing magnetic field and strong magnetic field generated by the magnetized coil pair Degaussing and re-magnetizing the micro-robot respectively; after the magnetization ends, changing the direction of the rotating magnetic field, and moving the micro-robot out of the radial magnetization slot; after using the micro-robot, performing For demagnetization operation, go to step S1.

In this embodiment, when the initial magnetization direction of the micro-robot is magnetization along the axial direction, the magnetized coil pair is energized to adjust the frequency and direction of the magnetic field. Sports mode, as shown in Figure 5. The micro-robot is controlled to walk into the radial magnetization slot by means of a rotating magnetic field. After the magnetization is finished, the microrobot rolls out from the radial magnetization groove through the ramp.

In this embodiment, modulating the frequency and direction of the magnetic field generated by the three-axis Helmholtz coil can realize that the micro-robot enters and leaves the magnetization slot through different motion modes.

In this embodiment, the magnetization direction of the micro-robot is controlled by the magnetic field generated by the three-axis Helmholtz coil.

The invention provides a system and method for an online magnetized columnar robot, by installing a pair of magnetized coils in the Y-axis direction of a three-axis Helmholtz coil, and designing on both sides of the central axis of the magnetized coil on the working platform magnetization tank, and then control the columnar robot to enter the corresponding magnetization tank for demagnetization and re-magnetization.

Example 1:

As shown in Figures 1-2, the online magnetization system of this embodiment includes a three-axis Helmholtz coil, a working platform, and a pair of magnetization coils. The working platform is a cuboid device with two magnetized grooves at one end, the magnetized grooves are rectangular, the length is 1.5 mm, and the diameter is 500 μm. The two magnetization slots are perpendicular to each other and both are located at the centermost position of a pair of magnetization coils, one is an axial magnetization slot and the other is a radial magnetization slot. The entire system is based on a three-axis Helmholtz coil.

When in use, continuously adjust the direction and frequency of the magnetic field generated by the three-axis Helmholtz coil, control the columnar robot to enter the corresponding magnetization slot, and then send an attenuated sinusoidal signal to the magnetization coil to demagnetize the columnar robot, and finally pass the magnetic field generated by the magnetization coil A strong magnetic field changes the magnetization direction of the columnar robot.

The online magnetization method of the above-mentioned online magnetization system for the columnar robot is as follows:

The initial magnetization direction of the columnar robot is perpendicular to the axis direction. When the movement of the columnar robot is controlled by the three-axis Helmholtz coil, the magnetization coil pair does not work. When the columnar robot is magnetized perpendicular to the axial direction, if the direction of the magnetic moment and the direction of the magnetic field are not perpendicular to each other, the columnar robot will quickly rotate to the direction perpendicular to the magnetic field; when the direction of the magnetic moment is parallel to the long axis of the columnar robot, in X-Z Or if the direction of the magnetic field is constantly changed in the Y-Z plane, the columnar robot will rotate around its own long axis, and finally form a rolling motion pattern on the workspace, as shown in the left figure of Figure 4. The rolling pattern of the columnar robot can generate effective displacement on the interface instead of ineffective reciprocating motion. When the magnetic field rotates around the Z-axis, the cylindrical robot will also rotate around the Z-axis in the X-Y plane, and finally stand upright on the interface of the workspace and rotate around the Z-axis to form a rotating motion pattern, as shown in the right figure of Figure 4.

If the initial state of the columnar robot is in the upright state, firstly control the magnetic field generated by the three-axis Helmholtz coil to rotate around the X axis to make the columnar robot fall down, and then continuously generate a rotating magnetic field in the X-Z or Y-Z plane to generate Roll, enter the radial magnetization groove, send a decaying sinusoidal signal to the magnetization coil to demagnetize the columnar robot, and finally change the magnetization direction of the columnar robot through the strong magnetic field generated by the magnetization coil. After the magnetization is over, apply a periodic oscillating magnetic field on the X-Z plane to make it roll out of the magnetization groove.

If the initial state of the columnar robot is flat, it will directly generate a rotating magnetic field in the X-Z or Y-Z plane, roll on the working plane, enter the radial magnetization slot, and demagnetize and remagnetize as above. After the magnetization is over, apply a periodic oscillating magnetic field on the X-Z plane to make it roll out of the magnetization groove.

After the robot rolls out of the magnetization tank, it can rotate around the x/y axis driven by the Helmholtz coil. The rotating robot generates a fluid field in the liquid, which creates a pressure difference on both sides of the cell, so that the cell rotates around the x/y axis. y-axis rotation. The magnetized robot can manipulate cells without contact.

The schematic diagram of Embodiment 1 is shown in Figure 6(A)-Figure 6(B).

Example 2:

As shown in Figures 1-2, the online magnetization system of this embodiment is the same as that of Embodiment 1.

The online magnetization method of the above-mentioned online magnetization system for the columnar robot is as follows:

The initial magnetization direction of the columnar robot is along its own long axis. When the movement of the columnar robot is controlled by the three-axis Helmholtz coil, the magnetization coil does not work. When the columnar robot is in the periodic oscillating magnetic field generated on the X-Z plane, the columnar robot can move forward and finally form a "walking" motion in the plane, as shown in the left figure of Figure 5. When the columnar robot is magnetized along its long axis, if the direction of its magnetic moment is inconsistent with the direction of the magnetic field, the columnar robot will quickly rotate to the direction of the magnetic field. If the magnetic field rotates around the Z axis, the columnar robot will also rotate around the Z axis in the X-Y plane, and finally form a non-vertical rotation motion mode in the workspace, as shown in the right figure of Figure 5.

If the initial state of the columnar robot is in the upright state, directly control the three-axis Helmholtz coil to generate a corresponding periodic oscillating magnetic field on the X-Z plane to make the columnar robot "walk" along the direction of the radial magnetization slot and enter the radial direction. Magnetization slot. An attenuated sinusoidal signal is then sent to the magnetizing coil to demagnetize the columnar robot, and finally the magnetization direction of the columnar robot is changed by the strong magnetic field generated by the magnetizing coil. After the magnetization is finished, a rotating magnetic field on the X-Z plane is applied to make it roll out of the magnetization groove along the slope.

If the initial state of the magnetically controlled columnar robot is flat and does not face the radial magnetization groove, it is necessary to apply a magnetic field rotating around the Z axis to make it stand, and then control the three-axis Helmholtz coil to generate the corresponding on the X-Z plane. The periodic oscillating magnetic field causes the columnar robot to produce a "walking" motion along the direction of the radial magnetization slot and enter the radial magnetization slot. An attenuated sinusoidal signal is then sent to the magnetizing coil to demagnetize the columnar robot, and finally the magnetization direction of the columnar robot is changed by the strong magnetic field generated by the magnetizing coil. After the magnetization is finished, a rotating magnetic field on the X-Z plane is applied to make it roll out of the magnetization groove along the slope.

The schematic diagram of Embodiment 2 is shown in FIG. 7 .

The above specific embodiments only describe the design principle of the present invention, and the shapes and names of the components in the description may be different and are not limited. Therefore, those skilled in the field of the present invention can modify or equivalently replace the technical solutions recorded in the foregoing embodiments; and these modifications and replacements do not deviate from the inventive spirit and technical solutions of the present invention, and all should belong to the protection scope of the present invention.

Claims (5)

1. An online magnetization system for micro-robots, characterized in that it comprises: Three-axis Helmholtz coil (1), working platform (2), magnetizing coil pair (3); The working platform (2) is a horizontal cuboid device, the center of the upper surface of the working platform (2) has an axial magnetization groove (2-1) and a radial magnetization groove (2-2), the The axial magnetization groove (2-1) and the radial magnetization groove (2-2) are rectangular; the axial magnetization groove (2-1) is parallel to the short side of the working platform (2), and the diameter The magnetization groove (2-2) is parallel to the long side of the working platform (2), the axial magnetization groove (2-1) is perpendicular to the radial magnetization groove (2-2), and the two grooves The distance between them is 1mm; The magnetized coil pair (3) includes a first magnetized coil (3-1) and a second magnetized coil (3-2), and the first magnetized coil (3-1) and the second magnetized coil (3-2) The ring openings are all parallel to the short side of the working platform (2), the first magnetizing coil (3-1) is arranged on a short side edge of the upper surface of the working platform (2), and the second The magnetizing coil (3-2) is deployed on the other short edge of the upper surface of the working platform (2); The working platform (2) and the pair of magnetizing coils (3) are built on the three-axis Helmholtz coil (1); The online magnetization refers to the ability to change the direction of the magnetic moment of the robot at any time during operation. 2. The online magnetization system according to claim 1, characterized in that, the online magnetization system has a control interface for receiving control instructions from the control module, and the control instructions include controlling Helmholtz coils and/or Or the instruction of the pair of magnetizing coils is used to control the Helmholtz coil to generate a uniform rotating magnetic field, and the pair of magnetizing coils is controlled to generate a strong magnetic field for magnetization. 3. The online magnetization system according to any one of claims 1-2, characterized in that, the axial magnetization groove (2-1) and the radial magnetization groove (2-2) are both rectangular, with a length of 1.5mm and a diameter of 500μm. 4. The online magnetization system according to any one of claims 1-2, wherein the direction and frequency of the magnetic field generated by the three-axis Helmholtz coil are adjusted by a single-chip microcomputer to control the micro-robot to enter the corresponding The magnetizing slot sends an attenuated sinusoidal signal to the pair of magnetizing coils to demagnetize the micro-robot, and finally changes the magnetization direction of the micro-robot through the strong magnetic field generated by the pair of magnetizing coils. 5. An online magnetization method for micro-robots, using the online magnetization system according to any one of claims 1-4, said online magnetization method comprising the following steps: Step S1: Receive a control command based on the control interface, the control command indicates the magnetization direction of the micro robot; if the control command is received, enter step S2; otherwise, the method ends; Step S2: Obtain the initial magnetization direction of the micro-robot, the initial magnetization direction includes axial or radial, the axial direction is parallel to the long side of the working platform, and the radial direction is parallel to the working platform The short side of the platform; the movement of the micro-robot is controlled by the three-axis Helmholtz coil, so that the micro-robot can move in any direction on the work platform. At this time, the magnetizing coil is powered off; if The initial magnetization direction is in the axial direction, enter step S3; if the initial magnetization direction is in the radial direction, enter step S4; Step S3: Control the direction of the rotating magnetic field generated by the three-axis Helmholtz coils, make the micro-robot enter the axial magnetization slot, and energize the magnetization coil pairs, and the decreasing magnetic fields and strong magnetic fields generated by the magnetization coil pairs respectively The magnetic field demagnetizes and re-magnetizes the micro-robot; after the magnetization is completed, the direction of the rotating magnetic field is changed, and the micro-robot is moved out of the axial magnetization slot; after the micro-robot is used, the micro-robot is Demagnetization operation, enter step S1; Step S4: Adjust the frequency and direction of the magnetic field generated by the three-axis Helmholtz coil, make the microrobot enter the radial magnetization slot, and energize the magnetized coil pair, the decreasing magnetic field and the strong magnetic field generated by the magnetized coil pair Degaussing and re-magnetizing the micro-robot respectively; after the magnetization ends, changing the direction of the rotating magnetic field, and moving the micro-robot out of the radial magnetization slot; after using the micro-robot, performing For demagnetization operation, go to step S1.