Preparation method of soft robot with programmable magnetization profile

Abstract

The invention discloses a preparation method of a soft robot with a programmable magnetization profile, which comprises the following steps: mixing and stirring an A part solution and a B part solution of Ecoflex 00-10to obtain a silicone rubber solution; mixing the magnetic powder with a silicone rubber solution to obtain a magnetic mixed solution; defoaming the magnetic mixed solution, pouring the defoamed magnetic mixed solution into a mold, carrying out magnetization, solidification and demolding treatment to obtain a plurality of magnetic modules, and storing the magnetic modules in a module library; cutting a silica gel film according to the appearance of the designed robot to obtain a profiling substrate matched with the robot in size; and the silica gel films are laid on the horizontal plane, a plurality of magnetic modules are taken, the magnetic modules are laid on the silica gel films according to the shapes of the silica gel films, the silica gel films are pressed to make full contact with and adhere to the silica gel films, and the soft robot is obtained. According to the invention, the robot is endowed with reconfiguration capability and magnetization profile reprogramming capability, and the method has the advantages of short manufacturing period, simple manufacturing process, low material consumption and the like.

Description

Technical Field

[0001] The invention relates to a soft robot, and in particular to a method for preparing a soft robot with programmable magnetization profile. Background Art

[0002] Patent 1: The invention application with application publication number CN115093705A discloses an organic composite material based on NdFeB, a frog-like soft robot and its preparation method, and proposes a soft robot that imitates biological structure and biological movement mode, changes the original structural shape and size during movement, so that it can have more degrees of freedom and multiple modes for driving, and realizes crawling, jumping, twisting, grasping and other action operations. Compared with traditional rigid robots, soft robots have better sensitivity, stretchability and environmental adaptability.

[0003] Disadvantages: Once the magnetic robot is magnetized, its magnetization profile is difficult to change. Under the action of an external magnetic field, it can only achieve a motion mode for a certain application environment. When the robot is used in a more complex environment, its deformation may not be suitable for the new environment because its magnetization profile cannot be changed. The lack of reprogrammable magnetization profile means that it cannot flexibly change its motion mode according to the scene, which limits its application.

[0004] Patent 2: The invention application with application publication number CN116168781A discloses a magnetic reconstruction programming device and method for magnetic soft materials. According to the method, after the magnetic soft robot is heated to a preset temperature, the magnetic particles in the magnetic soft robot are programmed to be magnetized and turned under the action of the composite spatial magnetic field generated by the magnet array. The magnetic soft robot is then cooled, and during the cooling process, the composite spatial magnetic field is ensured to continue to act on the magnetic soft robot until the phase change composite magnetic powder solidifies again, thereby completing the magnetic reconstruction of the magnetic soft robot. The magnetization turning direction of the magnetic particles in any area of ​​the magnetic soft robot can be arbitrarily controlled under the action of the composite spatial magnetic field.

[0005] Advantages: Only one step of magnetic reconstruction programming is required to achieve complex magnetization reconstruction, without the need for mold assistance or the support of large equipment.

[0006] Disadvantages: This method requires heating the material to complete the solid-liquid conversion, which consumes a lot of extra energy and limits the choice of materials (low melting point).

[0007] Patent 3: The invention application with application publication number CN115775701A discloses a method for preparing a programmable magnetic control array switch, which first uses a mixture of PDMS and magnetic material NdFeB to magnetize a soft robot with a specific magnetization profile. The obtained soft robot is then placed in a polytetrafluoroethylene mold, and the Ecoflex mixture is sucked with a syringe to connect the soft robots, which serves as a connecting material between the magnetic soft robots. The prepared programmable magnetic control array switch can be redirected by magnetic particles assisted by a magnetic field, and can control the closing and opening of different circuits through magnetic fields in different directions according to the on-site environment, and has high practicality.

[0008] Disadvantages: 1. This preparation process is relatively complicated and time-consuming, and it is necessary to wait for the silicone to solidify. 2. The array switch obtained by permanently connecting each soft robot with silicone is lacking in the reconfigurability of the magnetization profile. If you want to build an array switch with a different magnetization profile, you need to re-prepare the soft robot and connect it, which consumes a lot of materials.

[0009] Paper 1: VK Venkiteswaran, LFP Samaniego, J. Sikorski et al., “Bio-inspired terrestrial motion of magnetic soft millirobots,” IEEE Ro-bot. Autom. Lett., vol. 4, no. 2, pp. 1753–1759, Apr. 2019. Four soft bionic robots are proposed. The magnetic elastomer is made of Ecoflex 00-10 and magnetic particles PrFeB, and is magnetized by winding it on a specific mold, and then connected to the non-magnetic soft body with glue to obtain the bionic robot. The four designs imitate the motion of inchworms, turtles, quadrupeds, and millipedes respectively.

[0010] Disadvantages: Similar to Patents 1 and 3, although this design uses magnetic elastomers with different magnetization profiles to assemble different soft robots, the connection is permanently bonded with glue, and the magnetization profile of the bonded magnetic elastomer is difficult to change. If it is to be reconstructed into other soft robots, different elastomers need to be remade, which consumes a lot of materials and manufacturing time.

[0011] Paper 2: Y. Alapan, A Karacakol, S N Guzelhan et al., "Reprogrammable shape morphing of magnetic soft machines," Sci. Adv., vol. 6, 2020, Art. no. eabc6414. A method for reconfigurable magnetization profiles, namely the Curie temperature method, is proposed. Below the Curie temperature, magnetic materials behave as ferromagnetic materials, and the magnetization profile of the material is difficult to change. When the temperature is higher than the Curie point, the magnetic material behaves as paramagnetic materials, and the magnetization profile of the material can easily change with changes in the surrounding magnetic field.

[0012] Disadvantages: 1. The local heating of magnetic materials uses infrared heating, which requires specific equipment and consumes energy. (The solid-liquid conversion method mentioned in Patent 2 solves the equipment problem) 2. This method selects CrO with a lower Curie temperature. 2 (118℃), which limits the choice of materials.

[0013] Paper 3: X. Ke, H. Yong, F. Xu et al., “Synergistical mechanical design and function integration for insect-scale on-demand configurable multi-functional soft magnetic robots,” Soft Robot., 2023. A modular assembly strategy is proposed to quickly manufacture robots with different motion modes and different sensing capabilities. First, the magnetization profile of the magnetic elastomer is designed, and different sensing capabilities are designed on the surfaces of different elastomers. The body of the robot is a specially designed disc. When making the robot, you only need to match the magnetic elastomer with the disc notch. Its design is easy to disassemble and can be flexibly replaced according to different environments without consuming extra energy to change the magnetization profile.

[0014] Disadvantages: This strategy requires special mechanical design and high-precision 3D printing, which is costly to produce and still has room for improvement.

[0015] Paper 4: Y.Kim and X.Zhao, “Magnetic soft materials and robots”, Chem.Rev., vol.122, no.5, pp.5317-5364, 2022. A review of the design of magnetic robots in recent years, including the selection of magnetic materials, the molding method of magnetized profiles, and some demos of magnetic robots. This review can be used as a reference.

[0016] Soft robots are characterized by their soft bodies that can be driven by external stimuli. Thanks to the continuous development of smart materials, robots have demonstrated various driving strategies such as magnetic field, electricity, light, and shape memory alloys. Among them, magnetic drive is an actuation method with the characteristics of remote control, strong penetration, harmlessness, and fast response. It can be operated in confined spaces and has great potential in biomedical and engineering applications.

[0017] The motion capability of magnetic robots depends on the design and manufacture of magnetization profiles. Common methods for preparing magnetic soft robots are demolding, 3D printing, and spraying. Robots designed by these methods have achieved many complex bionic movements, such as jellyfish robots, inchworm robots, and quadruped robots. However, these robots are usually permanently bonded and lack the ability to reconfigure structures and magnetization curves for different mission environments.

[0018] In order to achieve reprogrammable magnetization profiles of magnetic robots, existing technologies include Curie temperature magnetic reprogramming, solid-liquid conversion reconstruction, and modular reconstruction. Curie temperature refers to the temperature at which the spontaneous magnetization intensity in a magnetic material drops to zero. When the magnetic material is heated above the Curie temperature, its magnetization direction can change. Applying an external magnetic field can change the magnetization direction a second time, and cooling it down to below the Curie temperature, its new magnetization direction will be fixed. The main disadvantage of this method is that the Curie temperature of most magnetic materials is very high and requires a lot of extra energy. The solid-liquid conversion reconstruction method is to mix magnetic powder with a low melting point metal (such as gallium, etc.). When the metal is in a liquid state, applying an external magnetic field can change the direction of the magnetic powder. Then cooling the metal to solidify, and this magnetization direction is retained. This method requires the use of specific materials and has limited accuracy.

[0019] The modular reconstruction method designs the desired magnetic robot by assembling magnetic modules with different magnetization profiles. When the application scenario needs to be changed, the magnetic module can be easily disassembled and replaced to assemble robots with different structures and different magnetization profiles. Commonly used materials are hard magnetic particles, such as neodymium iron boron. In order to ensure a large enough residual magnetism during the magnetization process, the magnetization equipment needs to output a large magnetic field. However, this equipment is very expensive and the preparation cost of the robot is high. At the same time, due to the large residual magnetism of hard magnets, it is difficult to control deformation under the action of a large external magnetic field strength.

[0020] In summary, the core points of the shortcomings of existing technologies are:

[0021] 1. Once the magnetic soft robot is manufactured, its magnetization profile is difficult to change.

[0022] 2. Magnetic robots are mostly permanently bonded using silicone or glue and lack reconfigurability.

[0023] 3. The magnetization profile reprogrammable technology requires a large amount of additional energy input and has limitations on the choice of magnetic materials.

[0024] 4. The production of robots has equipment thresholds and cannot be simple and fast. Summary of the invention

[0025] The purpose of the present invention is to overcome the above-mentioned problems and provide a method for preparing a soft robot with a programmable magnetic profile. The method not only gives the robot the ability to be reconfigured and the ability to reprogram the magnetic profile, but also has the advantages of short manufacturing cycle, simple manufacturing process, and low material consumption.

[0026] The purpose of the present invention is achieved through the following technical solutions:

[0027] A method for preparing a soft robot with programmable magnetic profile comprises the following steps:

[0028] (1) mixing and stirring the Ecoflex00-10 part A solution and part B solution according to a first mass ratio to obtain a silicone rubber solution;

[0029] Mixing the magnetic powder and the silicone rubber solution according to a second mass ratio to obtain a magnetic mixed solution;

[0030] (2) vacuum degassing the magnetic mixed liquid and pouring it into a mold, and obtaining a plurality of magnetic modules after magnetization, curing, and demolding, which are stored in a module library;

[0031] Repeat the above method to obtain a module library with modules of different magnetization profiles;

[0032] (3) According to the shape of the designed robot, the silicone film is cut to obtain a base that matches the size and conforms to the shape of the robot;

[0033] (4) Lay the silicone film flat on a horizontal plane, take out several magnetic modules from the module library, lay the magnetic modules on the silicone film according to the shape of the silicone film, and press each silicone film to make it fully contact and adhere to the silicone film, so as to obtain a soft robot with programmable magnetic profile.

[0034] In a preferred embodiment of the present invention, in step (1), the first mass ratio is 1:1, and the second mass ratio is 2:3.

[0035] In a preferred embodiment of the present invention, in step (1), the magnetic powder is iron particles with a diameter of 5 μm.

[0036] In a preferred embodiment of the present invention, in step (2), the stirred magnetic mixed liquid is placed in a vacuum drying oven and evacuated for 5 minutes to remove bubbles remaining in the liquid;

[0037] Pour the degassed magnetic mixture into a 3D printed mold for making a magnetic module;

[0038] applying an external magnetic field to arrange the magnetic particles in the magnetic mixed solution in a chain shape;

[0039] The bottom of the mold is heated to 80° C. and allowed to stand for 2 hours to allow the magnetic mixed liquid to fully solidify into a magnetic module;

[0040] The magnetic module is demoulded and then stored in a magnetic module library.

[0041] Furthermore, the applied external magnetic field is provided by two parallel permanent magnets, and the magnetic field strength of the external magnetic field is 150 mT.

[0042] Furthermore, the magnetic particles will be arranged in a chain shape under the action of an external magnetic field to align the direction of the magnetic field. Depending on the direction of the magnetic field, the direction of the magnetic chain inside the magnetic module after solidification will also be different, forming a magnetization profile of the magnetic module.

[0043] Furthermore, the magnetic particle chain of the magnetic module is oriented at 30°.

[0044] According to a preferred embodiment of the present invention, in step (2), the size of the magnetic module is 6 mm*4 mm*1 mm.

[0045] In a preferred embodiment of the present invention, in step (3), the thickness of the silicone film is 0.1 mm.

[0046] In a preferred embodiment of the present invention, the method for detecting the adhesion reliability between the magnetic module and the silicone film is as follows:

[0047] Glue the magnetic module to the connecting rod, spread the silicone film flat on the force sensor and fix it;

[0048] Control the universal testing machine to drive the connecting rod downward, and apply preload force to the magnetic module through the connecting rod; when the set preload force is reached, pause the universal testing machine and wait for the set time;

[0049] The universal testing machine is controlled to drive the connecting rod upward, and the magnetic module is pulled upward by the connecting rod until the magnetic module is completely separated from the silicone film; the force in the above process is detected by the force sensor, and the maximum absolute value measured is the maximum adhesion force of the magnetic module;

[0050] Place the magnetic module on a flat surface, place the control force sensor above the magnetic module and just in contact with the module, drive the permanent magnet to gradually approach the magnetic module, use a Gauss meter to record the magnitude of the magnetic field during this process, and read the reading of the force sensor, and measure the maximum force of the magnetic module acting on the force sensor under the action of the magnetic field. If the maximum force is less than the maximum adhesion force of the magnetic module, it means that the adhesion between the magnetic module and the silicone film is reliable; otherwise, the installation needs to be readjusted until the maximum adhesion force of the module is greater than the maximum force in the set magnetic field.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] 1. The magnetic module of the present invention uses magnetic particles and does not require large-scale magnetization equipment for magnetization. It only needs to use a permanent magnet to apply a magnetic field of about 100mT during the curing process to arrange the magnetic particles in a chain. After complete curing, the magnetic particle chain fixed inside the module provides magnetic anisotropy for the module.

[0053] 2. After designing the structure and magnetization profile of the robot, the soft robot can be manufactured within 5 minutes by cutting the silicone film of appropriate size and selecting magnetic modules from the module library for assembly. Compared with other soft robot manufacturing methods, it greatly saves manufacturing time.

[0054] 3. Silicone film is used as the soft skeleton for connection. While ensuring that the module will not fall off during the movement of the robot, the module can be manually separated and recycled from the robot, saving the material consumption and time cost of manufacturing the magnetic module.

[0055] 4. Soft robots can be flexibly manufactured according to the required deformation, and the manufactured robots have multiple motion modes to adapt to different application environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 Schematic diagram of the modular assembly design strategy of the present invention.

[0057] Figure 2 It is a schematic diagram of the manufacturing process of the magnetic module of the present invention.

[0058] Figure 3 It is a schematic diagram of the assembly process of the soft robot of the present invention.

[0059] Figure 4 FIG. 1 is a schematic diagram of an adhesion reliability verification operation of the present invention.

[0060] Figure 5 It is a schematic diagram of the deformation capability analysis of the magnetic module of the present invention.

[0061] Figure 6It is a schematic diagram of the soft robot of the present invention transforming from 1D to 2D (the arrows in the figure indicate the directions of the magnetic particle chains).

[0062] Figure 7 It is a schematic diagram of the transformation of the soft robot of the present invention from 2D to 3D (the arrows in the figure indicate the directions of the magnetic particle chains).

[0063] Figure 8 Schematic diagram of the turtle robot design and driving example of the present invention.

[0064] Fig. 9 Schematic diagram of the snake-like robot design and driving example of the present invention. DETAILED DESCRIPTION

[0065] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0066] Example 1

[0067] The method for preparing a soft robot with programmable magnetic profile of this embodiment comprises the following steps:

[0068] Step S1, taking Ecoflex00-10 part A solution and part B solution according to a first mass ratio, mixing and stirring to obtain a silicone rubber solution, and taking an appropriate amount of magnetic powder according to a second mass ratio in the plastic cup and mixing with the silicone rubber solution to obtain a magnetic mixed solution.

[0069] Step S2, vacuum degassing the magnetic mixed liquid and pouring it into a 3D printing mold, and obtaining a plurality of magnetic modules after magnetization, curing and demoulding, which are stored in a module library.

[0070] Step S3, cutting the silicone film according to the shape of the designed robot to obtain a base that matches the size of the robot.

[0071] Step S4, spreading the silicone film on a horizontal plane, using tweezers to pick up the magnetic modules in the module library and placing them on the silicone film, and then pressing them to make them fully contact and adhere to obtain a magnetic profile programmable soft robot.

[0072] The step S1 comprises:

[0073] Step S11, taking Ecoflex00-10 part A solution and part B solution according to a first mass ratio, mixing and stirring to obtain a silicone rubber solution.

[0074] Step S12, weighing the mass of the silicone rubber solution, taking an appropriate amount of magnetic powder according to the second mass ratio and mixing it with the silicone rubber solution in the plastic cup, and stirring at a constant speed for 10 minutes using a glass rod to obtain a magnetic mixed solution.

[0075] The first mass ratio is 1:1, and the second mass ratio is 2:3.

[0076] The magnetic powder is iron particles with a diameter of 5 μm.

[0077] See also Figure 2 , the step S2 comprises:

[0078] Step S21, placing the stirred magnetic mixed liquid in a vacuum drying oven and evacuating the vacuum for 5 minutes to remove the bubbles remaining in the liquid.

[0079] Step S22, pouring the degassed magnetic mixed solution into a mold for making a magnetic module.

[0080] Step S23, applying an external magnetic field to arrange the magnetic particles in the magnetic mixed solution in a chain shape.

[0081] Step S24, heating the bottom of the mold to 80° C. and leaving it to stand for 2 hours to allow the magnetic mixed liquid to fully solidify into a magnetic module.

[0082] Step S25, demoulding the magnetic module and storing it in a magnetic module library.

[0083] The size of the magnetic module made by the mold is 6mm*4mm*1mm.

[0084] The applied external magnetic field is provided by two parallel permanent magnets, and the magnetic field strength thereof is measured by a Gauss meter to be 150 mT.

[0085] The magnetic particles will be arranged in a chain shape under the action of an external magnetic field to align the direction of the magnetic field. According to the different directions of the magnetic field, the direction of the magnetic chain inside the magnetic module after curing will also be different, that is, the magnetization profile of the magnetic module is formed. The magnetic particle chain direction of the module is 30°.

[0086] In step S3, the thickness of the silicone film is 0.1 mm.

[0087] The step S4 comprises:

[0088] Step S41, laying the silicone film flat on a horizontal surface.

[0089] Step S42, according to a preset magnetization profile, a magnetic module is selected from the module library using tweezers and placed on the surface of the silicone film.

[0090] Step S43, pressing the magnetic module for 1 minute to allow it to fully contact the silicone film, and then letting it stand for 5 minutes to obtain a soft robot.

[0091] Example 2

[0092] See also Figure 1 ,The design of modular assembly strategy: cut the silicone film of the desired ,robot size, and select magnetic modules with different magnetization profiles from the ,module library. Through assembly, a soft robot can be obtained, whose morphological structure and motion mode are ,determined by the magnetization profile and assembly method of the magnetic ,module.

[0093] See also Figure 3 , Soft robot assembly method: The soft robot is assembled from a magnetic module and a silicone film, and a separate demonstration is given here; the silicone film is cut into a cross, and a magnetic module with a 30° magnetic particle chain structure is selected from the module library, and marked as module 1 and module 2 according to the different directions of the magnetic chain, and assembled as shown in the numbers in the figure; first, a spider-like robot is manufactured, and its four legs will shrink under the action of an external magnetic field; then the robot can be reconstructed, and the magnetic module is removed and recycled with tweezers and replaced with other magnetic modules in the module library to assemble into a claw robot; using this method, the robot's magnetization profile can be quickly reconstructed, so that the robot can produce different deformations to cope with different application scenarios.

[0094] See also Figure 4 , Adhesion reliability verification:

[0095] First, use a universal testing machine to test the adhesion between the magnetic module and the silicone film. The magnetic module is glued to the connecting rod with glue, and the silicone film is laid flat on the force sensor and fixed; the universal testing machine is controlled to move downward at a speed of 2.5mm / min to apply a preload force to the module; when the set preload force is reached, the universal testing machine is paused and waits for 2 seconds; then the universal testing machine is controlled to move upward at a speed of 2.5mm / min until the module is completely separated from the silicone film. The maximum force (negative value) measured during this process is the maximum adhesion force of the module, see Figure 4 (a) and 4(b).

[0096] Next, test the magnetic force generated by the magnetic module under the action of an external magnetic field. Place the magnetic module on a flat surface, control the height of the force sensor to just touch the module, use a stepper motor to slowly move the permanent magnet close to the module, use a gauss meter to record the magnitude of the magnetic field during this process, and read the reading of the force sensor. The maximum force generated under a magnetic field strength of 200mT is measured to be 22mN, which is less than the adhesion force under a preload of 120mN; in reality, the preload applied to the module is much greater than 120mN, so this adhesion is reliable, see Figure 4 (c) and 4(d).

[0097] See also Figure 5 ,Study on the magnetic response ability of magnetic modules,The factors affecting the deformation ability of magnetic modules include: ,magnetic field intensity, module length, module thickness, magnetic particle chain inclination, and magnetic particle mass fraction.

[0098] One end of the magnetic module is fixed on the bracket, and the other end is suspended in the air. Two parallel magnets are used to generate a magnetic field, and the influence of different parameters on the deformation capacity of the magnetic module is tested under the conditions of 40mT to 140mT. The two parallel magnets minimize the effect of the magnetic gradient force on the magnetic module. The study found that the shorter and thicker the module, the worse the deformation capacity, because its elastic bending moment is larger, so it is more difficult to deform. The inclination angle of the magnetic particle chain will also affect the deformation capacity of the magnetic module, and the module with a magnetic particle chain structure has a greater deformation capacity than the module without a magnetic particle chain structure under low magnetic field strength. The mass fraction of magnetic particles has little effect on the deformation capacity, because the module with a high mass fraction of magnetic particles will increase its Young's modulus and hinder its deformation while being subjected to a larger magnetic moment.

[0099] The ability of the magnetic module to continuously deform under the drive of a permanent magnet was also tested. The magnet was placed under the magnetic module, and the magnetic module was deformed by rotating the magnet, and the deformation of the magnetic module in one cycle was recorded. The experimental results show that the module can be used to drive soft robots.

[0100] See also Figure 6-7 , magnetization profile design assembly example.

[0101] By assembling the robot using the above method, the robot can achieve 1D to 2D and 2D to 3D deformation respectively. The magnetically driven deformation process is completely reversible and can be repeatedly driven as needed. The magnetic response is very fast, usually within milliseconds. The folding angle and deformation degree can also be adjusted by changing the magnetic field strength. The attached figure shows the deformation ability of the robot with different magnetization profiles.

[0102] See also Figure 8-9 , Example of bionic soft robot design:

[0103] The turtle robot consists of a non-magnetic silicon body (14 mm long, 6 mm wide, and 1 mm thick) and four magnetic modules (6 mm long, 4 mm wide, and 1 mm thick) for legs. Figure 8 As shown in (a), the magnetic flux orientation of modules M1 and M2 is 30°, and that of M3 and M4 is -30°. When the magnet approaches the robot, the magnetic torque received by the magnetic module increases, causing the robot to arch its body. The deformation of the module legs is mainly driven by the rotating permanent magnet. Due to the change in magnetic torque, the robot's legs repeatedly paddle, allowing the robot to crawl forward by generating thrust. We measured the displacement of the tip along the x and z directions within 10 seconds at a magnet rotation frequency of 1 Hz, as shown in Figure 2. Figure 8 (b) and 8(c). The relationship between the robot crawling speed and the magnet rotation frequency is shown in Figure 8 (d) Figure 8 As shown in (e), in addition to crawling, it can also swim in water under the attraction of a permanent magnet.

[0104] Inspired by the movement of snakes, a robot consisting of three magnetic modules was assembled. The total length of the robot is 30 mm, and the magnetic profile of the modules is as follows Fig. 9 (a) shows. M1 and M3 have the same magnetization curve. The magnetization profile of M2 is designed to be -60°. It has two motion modes: crawling mode and rolling mode, and the driving method is shown in the figure.

[0105] The above is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited to the above content. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A method for preparing a soft robot with programmable magnetic profile, characterized in that: The following steps are involved: (1) mixing and stirring the Ecoflex00-10 part A solution and part B solution according to a first mass ratio to obtain a silicone rubber solution; Mixing the magnetic powder and the silicone rubber solution according to a second mass ratio to obtain a magnetic mixed solution; (2) vacuum degassing the magnetic mixed liquid and pouring it into a mold, and obtaining a plurality of magnetic modules after magnetization, curing, and demolding, which are stored in a module library; Repeat the above method to obtain a module library with modules of different magnetization profiles; (3) According to the shape of the designed robot, the silicone film is cut to obtain a base that matches the size and conforms to the shape of the robot; (4) Lay the silicone film flat on a horizontal plane, take out several magnetic modules from the module library, lay the magnetic modules on the silicone film according to the shape of the silicone film, and press each silicone film to make it fully contact and adhere to the silicone film, so as to obtain a soft robot with programmable magnetic profile.

2. The method for preparing a soft robot with programmable magnetic profile according to claim 1, characterized in that: In step (1), the first mass ratio is 1:1, and the second mass ratio is 2:

3.

3. The method for preparing a soft robot with programmable magnetic profile according to claim 1, characterized in that: In step (1), the magnetic powder is iron particles with a diameter of 5 μm.

4. The method for preparing a soft robot with programmable magnetic profile according to claim 1, characterized in that: In step (2), the stirred magnetic mixed liquid is placed in a vacuum drying oven and evacuated for 5 minutes to remove the bubbles remaining in the liquid; Pour the degassed magnetic mixture into a 3D printed mold for making a magnetic module; applying an external magnetic field to arrange the magnetic particles in the magnetic mixed solution in a chain shape; The bottom of the mold is heated to 80° C. and allowed to stand for 2 hours to allow the magnetic mixed liquid to fully solidify into a magnetic module; The magnetic module is demoulded and then stored in a magnetic module library.

5. The method for preparing a soft robot with programmable magnetic profile according to claim 4, characterized in that: The applied external magnetic field is provided by two parallel permanent magnets, and the magnetic field strength of the external magnetic field is 150 mT.

6. The method for preparing a soft robot with programmable magnetic profile according to claim 5, characterized in that: The magnetic particles are arranged in a chain shape under the action of an external magnetic field to align the direction of the magnetic field. According to different directions of the magnetic field, the direction of the magnetic chain inside the magnetic module after solidification will also be different, forming a magnetization profile of the magnetic module.

7. The method for preparing a soft robot with programmable magnetic profile according to claim 6, characterized in that: The magnetic particle chains of the magnetic module are oriented at 30°.

8. The method for preparing a soft robot with programmable magnetic profile according to claim 1, characterized in that: In step (2), the size of the magnetic module is 6mm*4mm*1mm.

9. The method for preparing a soft robot with programmable magnetic profile according to claim 1, characterized in that: In step (3), the thickness of the silicone film is 0.1 mm.

10. The method for preparing a soft robot with programmable magnetic profile according to claim 1, characterized in that: The method for detecting the adhesion reliability between the magnetic module and the silicone film is as follows: Glue the magnetic module to the connecting rod, spread the silicone film flat on the force sensor and fix it; Control the universal testing machine to drive the connecting rod downward, and apply preload force to the magnetic module through the connecting rod; when the set preload force is reached, pause the universal testing machine and wait for the set time; The universal testing machine is controlled to drive the connecting rod upward, and the magnetic module is pulled upward by the connecting rod until the magnetic module is completely separated from the silicone film; the force in the above process is detected by the force sensor, and the maximum absolute value measured is the maximum adhesion force of the magnetic module; Place the magnetic module on a flat surface, place the control force sensor above the magnetic module and just in contact with the module, drive the permanent magnet to gradually approach the magnetic module, use a Gauss meter to record the magnitude of the magnetic field during this process, and read the reading of the force sensor, and measure the maximum force of the magnetic module acting on the force sensor under the action of the magnetic field. If the maximum force is less than the maximum adhesion force of the magnetic module, it means that the adhesion between the magnetic module and the silicone film is reliable; otherwise, the installation needs to be readjusted until the maximum adhesion force of the module is greater than the maximum force in the set magnetic field.

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