Six degree of freedom soft magnetic drive system and method

Abstract

The application discloses a kind of six degrees of freedom soft magnetic drive systems and methods, wherein the system includes: magnetic source module, for generating magnetic source magnetic field;Soft magnet, installed on mechanical device, for driving the movement of the mechanical device;Microcontroller, for controlling the operating parameter of magnetic source module;Wherein, soft magnet is magnetized under the action of magnetic source magnetic field to form secondary magnetic source, and its magnetic moment depends on the external magnetic field at the position of soft magnet, and the magnetized soft magnet is subjected to force and torque under the action of external magnetic field, and then drive the mechanical device to occur translation and rotation.The application controls magnetic source parameter, regulates and controls the three degrees of freedom force and three degrees of freedom torque that soft magnet receives, to realize the six degrees of freedom drive and active control of mechanical device.The application can be widely applied in magnetic drive field.

Description

Technical Field

[0001] This invention relates to the field of magnetic drive, and more particularly to a six-degree-of-freedom soft magnetic drive system and method. Background Technology

[0002] Minimally invasive medical devices (such as laparoscopic robots and transoral flexible robots) can reduce patient trauma and improve surgical safety. Minimally invasive instruments can more flexibly reach certain confined and complex spaces within the body, performing more complex medical tasks. While they can passively move within the body by utilizing the natural movements of organs (such as intestinal peristalsis) and the flow of bodily fluids, passively driven devices lack flexibility and controllability, limiting their functionality in medical tasks. Existing active actuation systems for minimally invasive devices can be divided into internal and external actuation systems. Internal actuation systems often achieve movement through internal drive mechanisms (such as the motorized legs and tail fins of capsule robots, and the cable-driven mechanisms of flexible robots), but integrating complex power supply systems and motion mechanisms within confined spaces is extremely difficult. External actuation primarily uses the magnetic force of an external magnetic field on the magnets mounted on the device to control it, avoiding the need for complex micro-drive mechanisms and power supply systems. However, existing magnetic drive systems mainly use permanent magnets as the force-bearing components of medical devices, which cannot apply torque around the principal axis of the magnetic moment. They can only achieve five degrees of freedom drive (three degrees of freedom force drive and two degrees of freedom torque drive), which reduces the dexterity and controllability of minimally invasive medical device manipulation. Summary of the Invention

[0003] In order to at least partially solve one of the technical problems existing in the prior art, the present invention aims to provide a six-degree-of-freedom soft magnetic drive system and method.

[0004] The technical solution adopted in this invention is:

[0005] A six-degree-of-freedom soft magnetic drive system includes the following steps:

[0006] The magnetic source module is used to generate the magnetic field.

[0007] A soft magnet, mounted on a mechanical device, is used to drive the movement of the mechanical device;

[0008] The microcontroller is used to control the operating parameters of the magnetic source module;

[0009] In this process, a soft magnetic body is magnetized under the action of a magnetic source to form a secondary magnetic source. Its magnetic moment depends on the external magnetic field at the location of the soft magnetic body. The magnetized soft magnetic body is subjected to force and torque under the action of the external magnetic field, which in turn drives the mechanical device to translate and rotate.

[0010] Furthermore, the magnetic source module includes a triaxial orthogonal Helmholtz coil or Maxwell coil, and the working space of the soft magnet is inside the three sets of orthogonal coils.

[0011] Furthermore, the magnetic source module includes a universal dipole magnetic source composed of three sets of orthogonal coils, and the working space of the soft magnet is outside the three sets of coils and in a three-dimensional space centered on the magnetic source.

[0012] Furthermore, the magnetic source module includes a single-axis coil magnetic source controlled by a six-axis robotic arm. The single-axis coil is fixed at the end of the robotic arm, and the position and posture of a single coil are controlled by the movement of the robotic arm. The working space of the soft magnet is in the space around the coil.

[0013] Furthermore, the mechanical device is a minimally invasive medical device, which includes a capsule robot or a flexible catheter.

[0014] Furthermore, the material of the soft magnet is a nickel-iron magnetic alloy or a nickel-iron amorphous alloy.

[0015] Furthermore, the soft magnet is installed at the end of the mechanical device, and the soft magnet is rigidly connected to the end of the mechanical device so that the force and torque on the soft magnet are transmitted to the mechanical device.

[0016] Furthermore, the soft magnet is shaped as an ellipsoid, an elliptical cylinder, or a cuboid, and is asymmetrical along its three axes, meaning that its equatorial radius a and b, and its polar radius (height) c are all unequal, and a > b > c.

[0017] Another technical solution adopted in this invention is:

[0018] A six-degree-of-freedom soft magnetic actuation method includes the following steps:

[0019] Establish a coupling model between the magnetic field and the force and torque acting on the soft magnetic body;

[0020] Based on the target position and attitude of the mechanical device and its current position and attitude, the motion trajectory of the mechanical device is obtained;

[0021] Calculate the required driving force and torque based on the motion trajectory;

[0022] Based on the calculated forces and torques, as well as the coupling relationship model, the driving magnetic field required for the soft magnet is calculated.

[0023] The magnetic source parameters are adjusted according to the calculated magnetic field; the magnetic source parameters include the current value of the electromagnetic coil and / or the position of the electromagnetic coil.

[0024] Furthermore, the coupling relationship model is specifically as follows:

[0025] Assuming the magnetized soft magnetic body is modeled as a magnetic dipole, the relationship between the torque on the soft magnetic body and the magnetic field is as follows:

[0026] τ=m×B

[0027] Where m=vR T χ a RB / μ0, where m is the magnetic moment of the soft magnet after being magnetized by an external magnetic field; R is the rotation matrix from the global coordinate system to the soft magnet coordinate system; and χ is the magnetic moment of the soft magnet after being magnetized by an external magnetic field. a It is the magnetic susceptibility of a soft magnetic material. B is the magnetic flux density at the soft magnetic material, μ0 is the free permeability; n a n represents the demagnetization coefficient of the longest axis a of a soft magnetic material. b n represents the demagnetization coefficient of the second major axis b of a soft magnetic material. c The demagnetization coefficient represents the shortest axis c of a soft magnetic material;

[0028] The relationship between the force and the magnetic field on a soft magnet is as follows:

[0029]

[0030] in, x, y, and z represent the three-axis coordinates.

[0031] The beneficial effects of this invention are as follows: By controlling the magnetic source parameters, this invention regulates the three-degree-of-freedom force and torque acting on the soft magnet, thereby achieving six-degree-of-freedom drive and active control of the mechanical device. Secondly, this invention transmits force and torque through a magnetic field, allowing for safe penetration of the human body and achieving contactless actuation. Furthermore, this magnetic drive scheme will enable more precise, flexible, and controllable manipulation and navigation of minimally invasive medical devices during minimally invasive diagnosis and treatment, effectively improving the automation and intelligence level of minimally invasive medical procedures. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following description is provided with accompanying drawings of the relevant technical solutions in the embodiments of the present invention or the prior art. It should be understood that the accompanying drawings described below are only for the purpose of clearly illustrating some embodiments of the technical solutions of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of a six-degree-of-freedom soft magnetic drive system based on a triaxial Helmholtz coil in an embodiment of the present invention;

[0034] Figure 2 This is a schematic diagram of the driving magnetic source design using a triaxial orthogonal coil in an embodiment of the present invention;

[0035] Figure 3This is a schematic diagram of a six-degree-of-freedom soft magnetic drive system based on a single-axis electromagnetic coil controlled by a six-axis robotic arm, as described in an embodiment of the present invention.

[0036] Figure 4 This is a flowchart of the steps of a six-degree-of-freedom soft magnetic drive method in an embodiment of the present invention;

[0037] Figure 5 This is a flowchart of the six-degree-of-freedom magnetic drive control system for a minimally invasive medical device based on soft magnets, as described in this embodiment of the invention.

[0038] Figure 6 This is a first schematic diagram comparing the forces (torques) acting on the soft magnet before and after magnetization in a water tank, according to an embodiment of the present invention.

[0039] Figure 7 This is a second schematic diagram comparing the force (torque) on the soft magnet before and after magnetization in the water tank in an embodiment of the present invention;

[0040] Figure 8 This is a third schematic diagram comparing the force (torque) on the soft magnet before and after magnetization in the water tank in an embodiment of the present invention. Detailed Implementation

[0041] The embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. The step numbers in the following embodiments are set only for ease of explanation, and there is no limitation on the order between the steps. The execution order of each step in the embodiments can be adaptively adjusted according to the understanding of those skilled in the art.

[0042] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0043] In the description of this invention, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0044] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0045] Soft magnets are ferromagnetic materials with high permeability and low coercivity. They are easily magnetized by external magnetic fields and become magnetic sources, experiencing forces and torques in such fields. Therefore, soft magnets can be fixed to medical devices as force-bearing elements to drive the devices. The electromagnetic coil, acting as the driving magnetic source, is placed externally. The soft magnet is magnetized by the magnetic field emitted by the driving source, forming a secondary magnetic source. Its magnetic moment (reflecting magnetic strength and orientation) depends on the magnetic field at the location of the driving source magnetizing the soft magnet. The magnetized soft magnet can be considered a dipole magnetic source. In the driving magnetic field, it experiences torques and forces depending on the local magnetic field and its gradient. Therefore, by understanding the magnetic-force coupling relationship of the forces acting on the soft magnet in the driving magnetic field, and combining this with a drive control system, precise control of micro-medical devices or other industrial micro-robots can be achieved.

[0046] See Figure 1 This embodiment provides a six-degree-of-freedom soft magnetic drive system, including:

[0047] The magnetic source module is used to generate the magnetic field.

[0048] A soft magnet, mounted on a mechanical device, is used to drive the movement of the mechanical device;

[0049] The microcontroller is used to control the operating parameters of the magnetic source module;

[0050] In this process, a soft magnetic body is magnetized under the action of a magnetic source to form a secondary magnetic source. Its magnetic moment depends on the external magnetic field at the location of the soft magnetic body. The magnetized soft magnetic body is subjected to force and torque under the action of the external magnetic field, which in turn drives the mechanical device to translate and rotate.

[0051] As an optional implementation, the soft magnet is made of nickel-iron magnetic alloy (1J85) or nickel-iron amorphous alloy (1K501), with a relative permeability μ r =10 4 -10 5 Its shape is an ellipsoid, elliptical cylinder, or cuboid, and its three axes are asymmetrical, that is, its equatorial radius a and b and its polar radius (height) c are not equal, and a > b > c.

[0052] As an alternative implementation, the soft magnet is installed at the end of the mechanical device, and the soft magnet is rigidly connected to the end of the mechanical device, so that the force and torque on the soft magnet can be effectively transmitted to the mechanical device.

[0053] As an alternative implementation, the magnetic source module includes a triaxial orthogonal Helmholtz coil or Maxwell coil, with the soft magnet's working space inside the three sets of orthogonal coils.

[0054] As an optional implementation, the magnetic source module includes a universal dipole magnetic source composed of three sets of orthogonal coils, and the working space of the soft magnet is in a three-dimensional space outside the three sets of coils and centered on the magnetic source.

[0055] As an optional implementation, the magnetic source module includes a single-axis coil magnetic source controlled by a six-axis robotic arm. The single-axis coil is fixed at the end of the robotic arm, and the position and posture of a single coil are controlled by the movement of the robotic arm. The working space of the soft magnet is in the space around the coil.

[0056] The above system will be explained in detail below with reference to the accompanying drawings and specific embodiments.

[0057] In this embodiment, the soft magnet is made of nickel-iron magnetic alloy (1J85) and is shaped into an elliptical cylindrical soft magnet with a relative permeability μ. r =1.246×10 5 The three axes have lengths of a = 30 mm, b = 12 mm, and c = 6 mm. The mechanical device is a minimally invasive medical device.

[0058] See Figure 1 , Figure 1 This embodiment uses a Helmholtz coil driving scheme. For the pure torque driving mode, a uniform external driving magnetic field is required to avoid the force on the soft magnetic body caused by the magnetic field gradient. At the same time, an asymmetric soft magnetic body is used to achieve three-degree-of-freedom torque driving. Figure 1 The system includes a three-axis Helmholtz coil (hereinafter referred to as three coil sets 1), a soft magnetic six-degree-of-freedom positioning system (hereinafter referred to as positioning system 2), a microcontroller 3, a power supply 4, and a soft magnetic body 5, which is mounted on the minimally invasive medical device. Specifically, the minimally invasive medical device is a capsule endoscopy robot, and the soft magnetic body 5 is mounted inside the capsule endoscopy robot. As another optional implementation, Figure 1 The three-axis Helmholtz coil in the circuit can be replaced by a three-axis Maxwell coil.

[0059] See Figure 5By adjusting the current in the three sets of coils 1, a uniform magnetic field of arbitrary direction and magnitude can be generated inside the coils. The soft magnetic body 5 inside the coil is magnetized under the influence of the magnetic field and, under the action of torque, can be oriented towards the target posture. The current posture of the soft magnetic body 5 can be determined by the external positioning system 2. The positioning system 2 is connected to the microprocessor 3, which compares the current posture with the target posture to calculate the required magnetic field using a magnetic-torque coupling model. The microprocessor 3 is connected to the power supply 4, and the microcontroller 3 issues commands to adjust the current in the three sets of coils 1 through the power supply 4 to generate the required magnetic field. The soft magnetic body 5 moves under the influence of the magnetic field until it reaches the target posture. This embodiment explains the principle of Helmholtz coil driving; however, the control principles of other magnetic sources are the same and will not be elaborated here.

[0060] Figure 2 A triaxial orthogonal omnidirectional magnetic source coil is required for both pure force-driven and full six-degree-of-freedom force and torque-driven modes, necessitating a non-uniform driving magnetic field with gradients. An omnidirectional dipole magnetic source composed of three sets of orthogonal coils allows for the control of the magnitude and direction of the driving magnetic field by adjusting the current in the three sets of coils, thereby enabling the control of the force and torque of the soft magnetic body.

[0061] Figure 3 It is a single-axis coil magnetic source controlled by a six-axis robotic arm. By adjusting the position and current of the single-axis coil, the magnitude and direction of the driving magnetic field can be controlled, thereby driving the soft magnetic body to move continuously to the desired position. Figure 3 The system shown includes a six-axis collaborative robotic arm 1, a single-axis electromagnetic coil magnetic source 2, and a minimally invasive medical device 3. The single-axis electromagnetic coil magnetic source 2 is located at the end of the six-axis collaborative robotic arm 1, and its position and orientation are changed by the six-axis collaborative robotic arm 1. In this embodiment, the minimally invasive medical device 3 is a capsule endoscope robot containing a soft magnet. When the patient swallows the capsule endoscope robot, it moves along the internal cavity 4 of the human body. Specifically, the position and orientation of the capsule endoscope robot are controlled by the single-axis electromagnetic coil magnetic source 2.

[0062] Based on the above system, such as Figure 4 As shown, this embodiment provides a six-degree-of-freedom soft magnetic drive method, including the following steps:

[0063] S1. Establish a coupling relationship model between the magnetic field and the force and torque on the soft magnetic body.

[0064] S2. Obtain the motion trajectory of the mechanical device based on its target position and attitude and its current position and attitude.

[0065] Based on the target posture of the minimally invasive instrument, its current posture, and the magnetic field workspace, the motion trajectory of the minimally invasive instrument is planned, and then a controller is designed.

[0066] S3. Calculate the required driving force and torque based on the motion trajectory.

[0067] S4. Based on the calculated force and torque, as well as the coupling relationship model, calculate the driving magnetic field required for the soft magnet.

[0068] S5. Adjust the magnetic source parameters according to the calculated magnetic field; where the magnetic source parameters include the current value of the electromagnetic coil and / or the position of the electromagnetic coil.

[0069] Based on the trajectory error of the controlled soft magnet, the required driving torque is calculated. Then, using a magneto-torque coupling model, the required driving magnetic field for the soft magnet is calculated. The current magnitudes of three pairs of electromagnetic coils are then adjusted to generate the desired magnetic field. The soft magnet is magnetized under the influence of the magnetic source's magnetic field, forming a secondary magnetic source. Its magnetic moment depends on the external magnetic field at the soft magnet's location. The magnetized soft magnet experiences torque under the influence of the external magnetic field, which in turn causes the minimally invasive instrument to rotate. By comparing the current new pose with the target pose, the magnetic source parameters are continuously updated, prompting the minimally invasive instrument to move until it reaches the target pose.

[0070] As an optional implementation method, the coupling relationship model is as follows:

[0071] Assuming the magnetized soft magnetic body is modeled as a magnetic dipole, the relationship between the torque on the soft magnetic body and the magnetic field is as follows:

[0072] τ=m×B

[0073] Where m=vR T χ a RB / μ0, where m is the magnetic moment of the soft magnet after being magnetized by an external magnetic field. R is the rotation matrix from the global coordinate system to the soft magnet's coordinate system, and χ... a It is the magnetic susceptibility of a soft magnetic material. B is the magnetic flux density at the soft magnet, and μ0 is the permeability of free space.

[0074] The relationship between the force and the magnetic field on a soft magnet is as follows:

[0075]

[0076] in,

[0077] The following explanation is based on the accompanying diagrams and experiments.

[0078] Figure 6 The capsule shell, containing a soft magnet, is placed in a water tank, in a static, suspended state where gravity and buoyancy are balanced. When a 1A current in the same direction is applied to a pair of coils, establishing a magnetic field perpendicular to the coils, the soft magnet immediately rotates about its longest axis (x), aligning its second longest axis (y) with the direction of the magnetic field. Figure 6 The upper part represents the state when it is not subject to a magnetic field. Figure 6 The lower part is when the soft magnetic body is subjected to a magnetic field in a certain direction, it rotates around the longest axis x, and finally the second longest axis y is in the same direction as the magnetic field.

[0079] Figure 7 The capsule shell, containing a soft magnet, is placed in a water tank, in a static, suspended state where gravity and buoyancy are balanced. When a 1A current in the same direction is applied to a pair of coils, establishing a magnetic field perpendicular to the coils, the soft magnet immediately rotates about its second longest axis (y), aligning its longest axis (x) with the direction of the magnetic field. Figure 7 The upper part represents the state when it is not subject to a magnetic field. Figure 7 The lower part is the soft magnetic body rotating around the second longest axis y when subjected to a magnetic field in a certain direction, and eventually the longest axis x is in the same direction as the magnetic field.

[0080] Figure 8 The capsule shell, containing a soft magnet, is placed in a water tank, in a static, suspended state where gravity and buoyancy are balanced. When a 1A current in the same direction is applied to a pair of coils, establishing a magnetic field perpendicular to the coils, the soft magnet immediately rotates around its shortest axis z, aligning its longest axis x with the direction of the magnetic field. Figure 8 The upper part represents the state when it is not subject to a magnetic field. Figure 8 The lower part is when the soft magnetic body is subjected to a magnetic field in a certain direction, it rotates around the shortest axis z, and eventually the longest axis x is in the same direction as the magnetic field.

[0081] In summary, this embodiment has at least the following advantages and beneficial effects compared to the prior art:

[0082] (1) The magnetic drive technology of this invention transmits force and torque through magnetic field, can safely penetrate the human body, realize contactless drive, and is suitable for the control of micro medical devices moving in the body in minimally invasive medicine.

[0083] (2) The magnetic drive technology of this invention applies three degrees of freedom force and three degrees of freedom torque to the end of the minimally invasive instrument by adjusting the external driving magnetic field and designing the geometry of the soft magnet, thereby achieving full six degrees of freedom dexterous drive.

[0084] In the foregoing description of this specification, references to terms such as "one embodiment," "another embodiment," or "some embodiments" indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0085] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

[0086] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the above embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A six-degree-of-freedom soft magnetic drive system, characterized in that, include: The magnetic source module is used to generate the magnetic field. A soft magnet is mounted on a mechanical device to drive the movement of the mechanical device; the soft magnet is ellipsoidal, cylindrical, or cuboid in shape and is asymmetric on three axes. The microcontroller is used to control the operating parameters of the magnetic source module; In this process, a soft magnetic body is magnetized under the action of a magnetic source to form a secondary magnetic source. Its magnetic moment depends on the external magnetic field at the location of the soft magnetic body. The magnetized soft magnetic body is subjected to force and torque under the action of the external magnetic field, which in turn drives the mechanical device to translate and rotate. The relationship between the torque on a soft magnet and the magnetic field is as follows: τ=m×B m=vR T x a RB / μ0 Where m is the magnetic moment of the soft magnetic body after being magnetized by an external magnetic field; R is the rotation matrix from the global coordinate system to the soft magnetic body coordinate system; and χ is the magnetic moment of the soft magnetic body after being magnetized by an external magnetic field. a is the magnetic susceptibility of the soft magnetic material, B is the magnetic flux density at the soft magnetic material, and μ0 is the permeability of free space.

2. The six-degree-of-freedom soft magnetic drive system according to claim 1, characterized in that, The magnetic source module includes a triaxial orthogonal Helmholtz coil or Maxwell coil, and the working space of the soft magnet is inside the three sets of orthogonal coils.

3. The six-degree-of-freedom soft magnetic drive system according to claim 1, characterized in that, The magnetic source module includes a universal dipole magnetic source composed of three sets of orthogonal coils. The working space of the soft magnet is outside the three sets of coils and in a three-dimensional space centered on the magnetic source.

4. The six-degree-of-freedom soft magnetic drive system according to claim 1, characterized in that, The magnetic source module includes a single-axis coil magnetic source controlled by a six-axis robotic arm. The single-axis coil is fixed at the end of the robotic arm, and the position and posture of a single coil are controlled by the movement of the robotic arm. The working space of the soft magnet is in the space around the coil.

5. A six-degree-of-freedom soft magnetic drive system according to claim 1, characterized in that, The mechanical device is a minimally invasive medical device, which includes a capsule robot or a flexible catheter.

6. A six-degree-of-freedom soft magnetic drive system according to claim 1, characterized in that, The soft magnet is made of nickel-iron magnetic alloy or nickel-iron amorphous alloy.

7. A six-degree-of-freedom soft magnetic drive system according to claim 1, characterized in that, The soft magnet is installed at the end of the mechanical device, and the soft magnet is rigidly connected to the end of the mechanical device so that the force and torque on the soft magnet are transmitted to the mechanical device.

8. A six-degree-of-freedom soft magnetic drive method, applied to a six-degree-of-freedom soft magnetic drive system as described in any one of claims 1-7, characterized in that, Includes the following steps: Establish a coupling model between the magnetic field and the force and torque acting on the soft magnetic body; Based on the target position and attitude of the mechanical device and its current position and attitude, the motion trajectory of the mechanical device is obtained; Calculate the required driving force and torque based on the motion trajectory; Based on the calculated forces and torques, as well as the coupling relationship model, the driving magnetic field required for the soft magnet is calculated. The magnetic source parameters are adjusted based on the calculated magnetic field. The magnetic source parameters include the current value of the electromagnetic coil and / or the orientation of the electromagnetic coil.

9. A six-degree-of-freedom soft magnetic drive method according to claim 8, characterized in that, The coupling relationship model is specifically as follows: Assuming the magnetized soft magnetic body is modeled as a magnetic dipole, the relationship between the torque on the soft magnetic body and the magnetic field is as follows: τ=m×B Where m=vR T χ a RB / μ0, where m is the magnetic moment of the soft magnet after being magnetized by an external magnetic field; R is the rotation matrix from the global coordinate system to the soft magnet coordinate system; and χ is the magnetic moment of the soft magnet after being magnetized by an external magnetic field. a is the magnetic susceptibility of the soft magnetic material, B is the magnetic flux density at the soft magnetic material, and μ0 is the permeability of free space. The relationship between the force and the magnetic field on a soft magnet is as follows: in,

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