CN114888798B - Micro-robot motion control system based on oscillating magnetic field platform - Google Patents

Abstract

A micro-robot motion control system based on an oscillating magnetic field platform comprises a Helmholtz coil; the alternating current power supply is used for providing alternating current for the Helmholtz coil to generate an oscillating magnetic field, and is controlled by the computer, and the generated oscillating magnetic field can be adjusted by changing the magnitude and the frequency of the alternating current provided for the Helmholtz coil, so that the motion gesture of the micro-robot is controlled; the rotary table drives the Helmholtz coil to rotate and changes the direction of the oscillating magnetic field; a camera for shooting the micro robot to obtain an image of the micro robot; the computer is used for analyzing the obtained micro-robot image to obtain the gesture and position information of the micro-robot, and transmitting the analysis results to the alternating current power supply and the controller respectively; and a controller for adjusting the rotation angle of the rotary table according to the analysis result of the position information of the micro robot, and changing the direction of the oscillating magnetic field, thereby adjusting the movement direction of the micro robot.

Description

Micro-robot Motion Control System Based on Oscillating Magnetic Field Platform

【Technical field】

The invention relates to the field of micro-robot control, in particular to a micro-robot motion control system based on an oscillating magnetic field platform.

【Background technique】

Micro-robots, especially magneto-controlled micro-robots, are widely used in biology, medicine and micro-assembly. In order to achieve precise motion control of magnetically controlled micro-robots, the existing technology has used the OctoMag magnetic operating system to generate gradient magnetic fields in three-dimensional space, or the combination of Helmertz coils and Maxwell coils to generate composite magnetic fields to control the motion state of magnetically controlled micro-robots. . Although a gradient magnetic field like the OctoMag magnetic force operating system can drive the motion of the magnetically controlled robot, it cannot easily change the direction of motion of the magnetically controlled microrobot, and the force calculation process of the magnetically controlled robot in the gradient magnetic field is complicated; in addition, using The combination of MHZ coils and Maxwell coils to generate a composite magnetic field requires the combination of multiple sets of coils to form a superimposed magnetic field, which is expensive, complex in device structure, complicated in device construction, and inefficient in driving magnetically controlled microrobots.

【Content of invention】

The purpose of the present invention is to provide a micro-robot motion control system based on an oscillating magnetic field platform, which uses a rotating table to drive the Helmertz coil to rotate, and generates an oscillating magnetic field with controllable rotation on a two-dimensional plane; and also collects and analyzes micro-robots. According to the difference between the real-time position and the expected target position, adjust the alternating current provided to the Helmertz coil and/or the rotation angle of the turntable to drive the micro-robot to move from the real-time position to the expected target position, and adjust in real time The motion pose of the microrobot. The above-mentioned system has a simple structure, no magnetic field superposition, convenient control, and can control the micro-robot to perform high-precision and high-response steering movements.

The purpose of the present invention is to realize through the following technical solutions:

A micro-robot motion control system based on an oscillating magnetic field platform, comprising:

Helmhertz coil;

an AC power supply, the AC power supply is connected to the Helmhertz coil, and is used to provide an AC current to the Helmhertz coil, so that the Helmhertz coil generates an oscillating magnetic field;

a rotating table, the rotating table is used to drive the Helmertz coil to rotate, and change the direction of the oscillating magnetic field;

a workbench, the workbench is set in the area covered by the oscillating magnetic field;

a micro robot, the micro robot is arranged on the workbench and can move on the workbench;

a camera, the camera is used to photograph the micro-robot to obtain an image of the micro-robot;

a computer, the computer is connected to the camera, the AC power supply, and the controller respectively, and is used to analyze the image of the micro-robot to obtain attitude and position information of the micro-robot, and transmit the analysis results to the AC power supply and the controller respectively. controller;

a controller, the controller is respectively connected with the computer and the turntable;

The controller adjusts the rotation angle of the rotating platform and changes the direction of the oscillating magnetic field according to the analysis result of the image of the micro-robot, thereby adjusting the moving direction of the micro-robot.

In one of the embodiments, the Helmertz coil includes a first circular conductor coil and a second circular conductor coil placed parallel and coaxially; the workbench is placed between the first circular conductor coil and the between the second circular conductor coils.

In one of the embodiments, the AC power supply provides a sinusoidal alternating current to the Helmhertz coil.

In one of the embodiments, the rotary table includes a base, and a motor disposed under the base and drivingly connected with the base.

In one of the embodiments, the controller is connected to the motor, and is configured to provide different driving currents to the motor, so that the motor drives the base to rotate in different directions and/or angles.

In one embodiment, the analyzing the image of the micro-robot by the computer includes: identifying and processing the image of the micro-robot by the computer to obtain the current position coordinates and coordinates of the micro-robot on the workbench. The pose of the microrobot.

In one embodiment, the computer generates a first control signal according to the difference between the current position coordinates of the micro-robot and the expected target position coordinates of the micro-robot on the workbench, and sends the The first control signal is input to the controller, so that the controller provides different driving currents to the motor.

In one embodiment, the computer generates a second control signal according to the difference between the current posture of the micro-robot and the expected movement posture of the micro-robot on the workbench, and sends the second control signal to A signal is input to the AC power supply, so as to adjust the magnitude and/or frequency of the AC current provided by the AC power supply to the Helmhertz coil.

Compared with the prior art, the present invention has the following beneficial effects:

The micro-robot motion control system based on the oscillating magnetic field platform provided by this application uses the rotating table to drive the Helmertz coil to rotate, and generates an oscillating magnetic field with controllable rotation on the two-dimensional plane; and also collects and analyzes the real-time position of the micro-robot, According to the difference between the real-time position and the expected target position, the real-time attitude and the expected attitude, adjust the alternating current provided to the Helmhertz coil and/or the rotation angle of the turntable to drive the micro-robot to move from the real-time position to the expected target position, and Adjust the motion posture of the micro-robot in real time. The above-mentioned system has a simple structure, no magnetic field superposition, convenient control, and can control the micro-robot to perform high-precision and high-response steering movements.

【Description of drawings】

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, other drawings can also be obtained based on these drawings without creative effort. in:

FIG. 1 is a schematic structural diagram of a micro-robot motion control system based on an oscillating magnetic field platform provided by the present application.

Fig. 2 is a three-dimensional schematic diagram of the rotary table and the Helmertz coil in the micro-robot motion control system based on the oscillating magnetic field platform shown in Fig. 1 .

FIG. 3 is a schematic side view corresponding to FIG. 2 .

FIG. 4 is a schematic top view of the structure corresponding to FIG. 2 .

FIG. 5 is a schematic diagram of the control flow of the micro-robot motion control system based on the oscillating magnetic field platform shown in FIG. 1 .

FIG. 6 is a schematic diagram of the oscillating magnetic field generated by the micro-robot motion control system based on the oscillating magnetic field platform shown in FIG. 1 .

FIG. 7 is a three-dimensional schematic diagram of the helical microrobot in one embodiment of the microrobot motion control system based on the oscillating magnetic field platform shown in FIG. 1 .

Fig. 8 is a schematic diagram of the trajectory of the helical microrobot shown in Fig. 7 driven by the microrobot motion control system.

Reference signs: 10, Helmertz coil; 11, first circular conductor coil; 12, second circular conductor coil; 20, AC power supply; 30, rotary table; 31, base; 32, motor; 40, Workbench; 41, support rod; 42, flat panel; 50, video camera; 60, computer; 70, controller; 80, spiral micro-robot; 81, conical head; 82, spiral tail.

【Detailed ways】

In order to make the above purpose, features and advantages of the present application more obvious and understandable, the specific implementation manners of the present application will be described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described here are only used to explain the present application, but not to limit the present application. In addition, it should be noted that, for the convenience of description, only some structures related to the present application are shown in the drawings but not all structures. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

The terms "comprising" and "having" and any variations thereof in this application are intended to cover a non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but optionally also includes unlisted steps or units, or optionally further includes For other steps or units inherent in these processes, methods, products or apparatuses.

Reference herein to an "embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The occurrences of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is understood explicitly and implicitly by those skilled in the art that the embodiments described herein can be combined with other embodiments.

1 to 4, the micro-robot motion control system based on an oscillating magnetic field platform provided by an embodiment of the present application, the micro-robot motion control system based on an oscillating magnetic field platform includes a Helmertz coil 10, an AC power supply 20, a rotating stage 30, workbench 40, video camera 50, computer 60, controller 70, and microrobot.

The AC power source 20 is connected to the Helmhertz coil 10 and is used to provide an AC current to the Helmhertz coil 10 to make the Helmhertz coil 10 generate an oscillating magnetic field. Optionally, the AC power supply 20 can provide a sinusoidal alternating current to the Helmertz coil 10, so that the Helmertz coil 10 can generate an oscillating magnetic field whose direction and intensity change sinusoidally and periodically with time under the action of the sinusoidal alternating current. The magnetic field formed by the Helmhertz coil 10 at any moment during the whole process is uniform and has no gradient force.

The Helmhertz coil 10 includes a first circular conductor coil 11 and a second circular conductor coil 12 placed parallel to and coaxial with each other. When the AC power supply 20 supplies alternating current to the first circular conductor coil 11 and the second circular conductor coil 12 , the space between the first circular conductor coil 11 and the second circular conductor coil 12 will generate an oscillating magnetic field. Wherein, the space between the first circular conductor coil 11 and the second circular conductor coil 12 will generate an oscillating magnetic field as shown in FIG. 6 .

The workbench 40 is set in an area covered by a uniform magnetic field, and the micro-robot is set on the workbench 40 and can move on the workbench 40 . Optionally, the workbench 40 is arranged between the first circular conductor coil 11 and the second circular conductor coil 12, so as to ensure that the micro-robot is always subjected to the oscillating magnetic field. The workbench 40 may include a support rod 41 and a flat plate 42 . The support rod 41 is vertically arranged on the rotating table 30, and the flat plate 42 is fixedly arranged above the support rod 41, providing a planar space area for the movement of the micro-robot. Both the support rod 41 and the flat plate 42 are located between the first circular conductor coil 11 and the second circular conductor coil 12 . The support rod 41 and the flat plate 42 can be made of non-magnetic materials such as plastics. While the turntable 30 rotates, the table 40 can remain stationary.

The rotating table 30 is used to drive the Helmertz coil 10 to rotate and change the direction of the oscillating magnetic field. The turntable 30 may include a base 31 , and a motor 32 disposed below the base 31 and drivingly connected to the base 31 . The base 31 is in the shape of a circular plate as a whole. The drive output rod of the motor 32 can be connected with the center of the circle of the base 31 , and the base 31 is driven to rotate with the axis vertically passing through the center of the circle as the rotation axis. When the base 31 is driven by the motor 32 to rotate, it can synchronously drive the Helmertz coil 10 to rotate on the two-dimensional plane, thereby changing the direction of the oscillating magnetic field and obtaining a controllable rotating oscillating magnetic field.

The camera 50 is arranged above the workbench 40, and is used for photographing the micro-robot to obtain an image of the micro-robot. The camera 50 may be but not limited to be an industrial camera.

The computer 60 is connected with the camera 50 for receiving the images of the micro-robot captured by the camera 50 and performing recognition processing on the images of the micro-robot to obtain the current position coordinates of the micro-robot on the workbench 40 or the attitude of the micro-robot.

Optionally, the computer 60 can generate a first control terminal signal according to the difference between the current position coordinates of the micro-robot on the workbench 40 and the expected target position on the workbench, and input the first control terminal signal to the control At this time, the controller 70 will provide different driving currents to the motor 32, so that the motor 32 drives the base 31 to rotate in different directions and/or angles. Wherein, the above-mentioned difference may include, but not limited to, a distance difference and/or an orientation difference between the current location coordinates and the desired target location coordinates.

Optionally, the computer 60 can generate a second control terminal signal according to the difference between the current motion posture of the micro-robot on the workbench 40 and the expected motion posture on the workbench, and input the second control terminal signal to the AC power supply 20, At this time, the magnitude and/or frequency of the alternating current provided by the alternating current power source 20 to the Helmhertz coil 10 is adjusted. Wherein, the above-mentioned difference may include, but not limited to, the difference between the current movement speed and movement range of the micro-robot and the expected movement speed and movement range.

The computer 60 can use the proportional/integral/differential algorithm (PID) according to the deviation to generate a control terminal signal according to the difference between the above-mentioned coordinates or the difference between the attitudes, so as to ensure that the subsequent controller 70 can accurately control the work of the rotary table 30 .

The AC power supply 20 controls the motion posture of the micro-robot by adjusting the magnitude and/or frequency of the AC power supplied to the Helmertz coil 10 . A controller 70 is connected to the computer 60 and the turntable 30 respectively. The controller 70 can adjust the rotation angle of the turntable 30 and change the direction of the oscillating magnetic field according to the control terminal signal from the computer 60, thereby controlling the movement direction of the micro-robot.

Referring to FIG. 5 , the AC power source 20 adjusts the magnitude and/or frequency of the AC power supplied to the Helmertz coil 10 according to the second control terminal signal. When the magnitude and/or frequency of the alternating current provided by the AC power source 20 to the Helmhertz coil 10 changes, the magnitude and/or frequency of the oscillating magnetic field generated by the Helmhertz coil 10 will change synchronously, so that the micro-robot receives the force from the oscillating magnetic field. The magnetic torque will also change, so that the motion state of the micro-robot on the workbench 30 will change.

The controller 70 can also send a drive current signal to the motor 32 of the turntable 30 according to the first control terminal signal, thereby adjusting the rotation angle and/or direction of the base 31 of the turntable 30, that is, the base 31 rotates clockwise. Or the size of the rotation angle in the counterclockwise direction, thereby changing the rotation direction of the vibrating magnetic field. Through the above control process, it is possible to perform closed-loop control on the movement of the micro-robot, and accurately move the micro-robot from its current position to a desired target position.

Please refer to FIG. 7 to FIG. 8 , in practical application, the micro-robot motion control system based on the oscillating magnetic field platform of the present application can be used to drive the helical micro-robot 80 to move. The helical microrobot 80 has a cylindrical shape as a whole, wherein the diameter of the cylindrical shape may be 3mm and the length may be 12mm. The helical microrobot 80 can be composed of a conical head 81 and a helical tail 82, and three helical wires are arranged on the periphery of the helical tail 82. The conical head 81 is inlaid with a cylindrical permanent magnet to provide driving force for the helical microrobot 80 . When the helical microrobot 80 is in the oscillating magnetic field generated by the Helmertz coil 10, the conical head 81 is subjected to the action of the magnetic torque, so that the helical microrobot 80 performs high-speed rotational motion along its central axis, and at the same time the helical tail 82 The above-mentioned high-speed rotational motion is converted into a forward driving force to realize the forward motion of the helical microrobot 80 .

Specifically, the micro-robot motion control system based on the oscillating magnetic field platform of the present application drives the helical micro-robot 80 to move as follows:

(1) placing the helical microrobot 80 at a specific position on the workbench 40;

(2) Provide an alternating current of 3A to the Helmertz coil 10 through the alternating current power supply 20, thereby generating an oscillating magnetic field on the plane corresponding to the workbench 40, and driving the helical microrobot 80 to move forward in a straight line;

(3) Control the rotation of the turntable 30 to make the helical microrobot 80 turn; such as controlling the turntable 30 to rotate 90°, the direction of the oscillating magnetic field also rotates 90°, at this time the direction of motion of the helical microrobot 80 is the same as the direction of the oscillating magnetic field alignment, so as to achieve the purpose of turning the helical microrobot 80;

(4) When the helical microrobot 80 moves to the desired target position, the alternating current of the Helmertz coil 10 is turned off, and the helical microrobot 80 stops moving forward.

In actual operation, the above step (3) and step (4) can be repeatedly performed, so that the helical microrobot 80 can move along the planned trajectory. It can be seen from FIG. 8 that the helical microrobot 80 can move along an "S"-shaped trajectory or a "U"-shaped trajectory in a two-dimensional plane driven by a microrobot motion control system based on an oscillating magnetic field platform.

The above is only a specific embodiment of the present invention, and any other improvements made on the premise of the concept of the present invention are regarded as the protection scope of the present invention.

Claims (7)

1. A micro-robot motion control system based on an oscillating magnetic field platform, comprising:

a Helmholtz coil (10);

an alternating current power supply (20), wherein the alternating current power supply (20) is connected with the Helmholtz coil (10) and is used for providing alternating current for the Helmholtz coil (10) so that the Helmholtz coil (10) generates an oscillating magnetic field;

the rotary table (30) is used for driving the Helmholtz coil (10) to rotate and changing the direction of the oscillating magnetic field;

a table (40), wherein the table (40) is arranged in an area covered by the oscillating magnetic field;

a micro robot provided on the table (40) and movable on the table (40);

the camera (50) is used for shooting the micro-robot to obtain an image of the micro-robot; the computer (60) is respectively connected with the camera (50), the alternating current power supply (20) and the controller (70) and is used for analyzing the image of the micro-robot to obtain the gesture and position information of the micro-robot and respectively transmitting the analysis result to the alternating current power supply (20) and the controller (70);

the controller (70) is respectively connected with the computer (60) and the rotary table (30);

the controller (70) adjusts the rotation angle of the rotary table (30) according to the analysis result of the image of the micro-robot, and changes the direction of the oscillating magnetic field, thereby adjusting the movement direction of the micro-robot;

the Helmholtz coil (10) comprises a first circular conductor coil (11) and a second circular conductor coil (12) which are coaxially arranged in parallel; the workbench (40) is arranged between the first circular conductor coil (11) and the second circular conductor coil (12).

2. The oscillating magnetic field platform based micro-robot motion control system according to claim 1, wherein the ac power supply (20) provides sinusoidal ac current to the helmholtz coil (10).

3. The oscillating magnetic field platform based micro-robot motion control system according to claim 1, characterized in that the rotary table (30) comprises a base (31) and a motor (32) arranged below the base (31) and in driving connection with the base (31).

4. A micro-robot motion control system based on an oscillating magnetic field platform according to claim 3, characterized in that the controller (70) is connected to the motor (32) for providing different driving currents to the motor (32) so that the motor (32) drives the base (31) to perform angular rotations in different directions and/or magnitudes.

5. The oscillating magnetic field platform based micro-robot motion control system of claim 4, wherein the computer (60) analyzing the micro-robot image comprises: the computer (60) performs recognition processing on the image of the micro-robot to obtain the current position coordinate of the micro-robot on the workbench and the posture of the micro-robot.

6. The oscillating magnetic field platform based micro-robot motion control system of claim 5, wherein the computer (60) generates a first control signal based on a difference between a current location coordinate of the micro-robot and a desired target location coordinate of the micro-robot at the table (40), and inputs the first control signal to the controller (70), thereby causing the controller (70) to provide different driving currents to the motor (32).

7. The oscillating magnetic field platform based micro-robot motion control system according to claim 6, wherein the computer (60) generates a second control signal according to a difference between a current posture of the micro-robot and a desired motion posture of the micro-robot at the table (40), and inputs the second control signal to the ac power supply (20), thereby adjusting a magnitude and/or a frequency of an ac current supplied from the ac power supply (20) to the helmholtz coil (10).