Magnetically-actuated jellyfish-imitating soft robot and preparation and driving method thereof

Abstract

The invention discloses a magnetically-actuated jellyfish-imitating soft robot and a preparation and driving method thereof, and relates to the technical field of bionic soft robots, the magnetically-actuated jellyfish-imitating soft robot comprises an upper soft body layer, a lower soft body layer and a plurality of supporting pieces, the upper soft body layer, the lower soft body layer and the supporting pieces are made of magnetically-controlled soft materials, N upper layer tentacles are evenly arranged on the edge of the upper soft body layer at intervals in the circumferential direction, and N lower layer tentacles are arranged on the edge of the lower soft body layer at intervals in the circumferential direction; n lower layer tentacles are uniformly arranged on the edge of the lower soft body layer at intervals in the circumferential direction, and N is an even number and is larger than or equal to 4; the two ends of the supporting piece are connected with the upper soft body layer and the lower soft body layer respectively, the connecting positions are located between the adjacent upper layer tentacles and between the adjacent lower layer tentacles respectively, and the upper soft body layer and the lower soft body layer are separated from each other through supporting of the supporting piece to form a space capable of containing loads. The requirements for high elasticity, high toughness and excellent magnetic deformation of a soft robot base body can be met, and the problems that an existing jellyfish-imitating robot is difficult in material flexibility regulation and control, slow in magnetic drive response, single in structure and insufficient in motion stability are solved.

Description

Technical Field

[0001] This invention relates to the field of biomimetic soft robot technology, specifically to a magneto-actuated jellyfish-inspired soft robot and its fabrication and actuation method. Background Technology

[0002] As robotics technology expands into flexible interaction and special environment applications, traditional rigid robots, due to insufficient motion flexibility and limited environmental adaptability, are struggling to meet the demands of complex scenarios. Against this backdrop, soft robots, with soft materials as their core matrix, are gradually becoming a research hotspot due to their unique advantages. Soft robots achieve flexible movement and precise deformation through diverse actuation methods, possessing strong environmental adaptability, high interaction safety, outstanding motion flexibility, and convenient manufacturing characteristics. They can conform to irregular surfaces, traverse narrow spaces, and require no complex transmission components. They can be rapidly manufactured using simple processes, balancing lightweight design and cost control, demonstrating broad application prospects in fields such as flexible interaction, biomedicine, and special environment detection.

[0003] Magnetic actuation, with its advantages of wireless control, rapid response, and operation in enclosed spaces, has become an important development direction for soft robot drive technology. However, current magnetically driven soft robots still face many challenges in terms of material properties and structural design, which severely restrict their application scope and performance improvement.

[0004] In terms of material properties, the core issues are concentrated in two main areas: insufficient elasticity and toughness, and the difficulty in achieving functional balance. On the one hand, the flexible materials used in existing soft robots generally suffer from poor elasticity and toughness, making them unable to adapt to complex deformations such as bending and torsion during repeated movements. They are prone to fatigue cracks after cyclic stress, resulting in a significant reduction in their cycle life and making it difficult to meet the actual needs of long-term stable operation. On the other hand, magnetically driven soft robots have extremely high requirements for the comprehensive performance of materials, but most existing materials cannot simultaneously achieve a harmonious balance of high elasticity, high strength, and high magnetic responsiveness. This technical challenge in achieving functional balance directly limits the motion capability, load performance, and work efficiency of magnetically driven soft robots.

[0005] In terms of structural design and motion performance, current magnetically driven soft robots generally suffer from relatively simple structures and limited motion modes, making it difficult to achieve multimodal motion to flexibly adapt to complex and ever-changing application environments. Among them, jellyfish-inspired soft robots, an important branch of magnetically driven soft robots, have certain potential for underwater operations by leveraging the biological movement characteristics of jellyfish. However, their structural designs are mostly limited to a single umbrella-shaped structure, resulting in limited load capacity, poor functional expandability, and relatively weak practical application capabilities.

[0006] For example, Chinese invention patent CN 116789985 A discloses a biomimetic jellyfish hydrogel robot, its preparation method, and its application. This biomimetic jellyfish hydrogel robot includes a main body and N side arms (N being an integer ≥3) connected to the main body. The main body contains water and a first polymer. Each side arm independently contains water, a second polymer, an anti-settling agent, and magnetic particles dispersed in the second polymer. Both the first and second polymers are hydrophilic cross-linked polymers, and the magnetic particles are composed of neodymium iron boron and an insulating layer coating their surface. While this biomimetic jellyfish hydrogel robot achieves wireless drive, possesses flexibility, good biocompatibility, and hydrophilic properties, and can achieve various movement postures through a simple body structure, its structural design still has significant room for improvement in terms of load capacity, precise control of complex movement postures, and stability during long-term cyclic operation. Furthermore, the hydrogel material is soft, has low mechanical strength, and is easily torn or deformed in complex aquatic environments. It is also sensitive to water quality such as pH or temperature, and the hydrogel substrate is prone to swelling, leading to functional failure.

[0007] Therefore, developing a magnetically driven jellyfish-like soft robot that combines excellent material properties with optimized structural design to solve problems such as insufficient elasticity and toughness, low functional integration, and limited load and motion performance in existing technologies has become an urgent technical issue to be addressed in this field. Summary of the Invention

[0008] This invention aims to provide a magnetically actuated jellyfish-inspired soft robot and its preparation and actuation method, in order to meet the requirements of high elasticity, high toughness and excellent magnetic deformation of the soft robot substrate, and to solve the problems of current jellyfish-inspired robots such as difficulty in controlling material flexibility, slow magnetic actuation response, simple structure and insufficient motion stability.

[0009] To solve the above technical problems, the specific solution adopted by the present invention is as follows: a magneto-actuated jellyfish-like soft robot, comprising an upper soft layer, a lower soft layer, and multiple support plates made of magnetically controlled soft material. The edge of the upper soft layer is provided with N upper tentacles evenly spaced along the circumferential direction, and the edge of the lower soft layer is provided with N lower tentacles evenly spaced along the circumferential direction. The upper tentacles and lower tentacles correspond one-to-one, and the end of each upper tentacle is connected to its corresponding lower tentacle. N is an even number and N≥4. The two ends of the support plates are respectively connected to the upper soft layer and the lower soft layer, and the connection positions are respectively located between adjacent upper tentacles and between adjacent lower tentacles. The upper soft layer and the lower soft layer are separated from each other by the support of the support plates to form a space that can accommodate the load.

[0010] As a further optimization of the above technical solution, the upper software layer and the lower software layer have the same size.

[0011] As a further optimization of the above technical solution, N=4.

[0012] As a further optimization of the above technical solution, the connections between the upper and lower tentacles, as well as between the two ends of the support plate and the upper and lower soft layers, are all adhesive.

[0013] A method for fabricating a magnetoactuated jellyfish-inspired soft robot includes the following steps:

[0014] S1. Cut the magnetically controlled soft material to obtain the above-mentioned upper soft layer, lower soft layer and support sheet;

[0015] S2. Magnetize the upper soft layer, the lower soft layer and the support sheet respectively. The magnetization direction angle of the upper soft layer and the lower soft layer is 45°. The support sheet is folded in half and then magnetized, with the folded support sheet perpendicular to the magnetic field direction.

[0016] S3. After magnetization, the upper soft layer, lower soft layer and support plate are bonded together. The end of each upper tentacle is bonded to its corresponding lower tentacle. The two ends of the support plate are bonded to the upper soft layer and the lower soft layer respectively, thus obtaining the magneto-actuated jellyfish-like soft robot.

[0017] As a further optimization of the above technical solution, the preparation method of the magnetic control soft material is as follows: styrene-isoprene-styrene block copolymer, polybutadiene and p-xylene are mixed evenly and then neodymium iron boron magnetic particles are added to obtain a polymer solution mixed with magnetic particles. The polymer solution mixed with magnetic particles is then spin-coated onto a carrier and dried to obtain a thin film loaded on the carrier. This thin film is the magnetic control soft material.

[0018] As a further optimization of the above technical solution, in step S1, the polymer solution mixed with magnetic particles is spin-coated onto the carrier using a gradient rotation speed, dried, spin-coated again, dried, and repeated multiple times to obtain a film loaded on the carrier with a film thickness of 0.4-0.5 mm; the gradient rotation speed is specifically as follows: first, pre-spread at a low speed of 750-850 rpm for 10-15 s, and then increase to a high speed of 1150-1250 rpm for 20-25 s.

[0019] As a further optimization of the above technical solution, in step S1, the weight ratio of styrene-isoprene-styrene block copolymer to polybutadiene is 10:0.7-1.2:20-30; the weight ratio of neodymium iron boron magnetic particles to styrene-isoprene-styrene block copolymer is 1:2-2.5.

[0020] A driving method for a magneto-actuated jellyfish-inspired soft robot includes:

[0021] A magneto-actuated jellyfish-like soft robot is placed on land and a magnetic field is applied vertically downwards to enable it to crawl horizontally on land.

[0022] Alternatively, a magneto-actuated jellyfish-like soft robot can be placed on land and a horizontal magnetic field can be applied to achieve horizontal rolling on the land;

[0023] Alternatively, a magneto-actuated jellyfish-like soft robot can be placed in water and a vertically downward magnetic field can be applied to enable it to crawl horizontally in the water.

[0024] Alternatively, a magneto-actuated jellyfish-like soft robot can be placed in water and a horizontal magnetic field can be applied to achieve underwater propulsion and translation.

[0025] Alternatively, first adjust the overall density of the magneto-actuated soft robot to be greater than that of water, then place the magneto-actuated jellyfish-like soft robot in the water and apply a magnetic field pointing vertically downwards to enable it to float, swim, and jump in the water.

[0026] As a further optimization of the above technical solution, the overall density of the magneto-actuated soft robot is adjusted by adding a buoyancy module, and the mass ratio of the buoyancy module to the magneto-actuated soft robot is 1:155-165.

[0027] As a further optimization of the above technical solution, during the process of horizontal crawling on land, the magnetic field with a vertical downward direction has a magnitude of 18mT, a driving frequency of 2.5Hz, and a duty cycle of 30%.

[0028] During the process of achieving horizontal rolling of the land, the horizontal magnetic field is 15-18 mT, the duty cycle is 50%, and the driving frequency is 1 Hz.

[0029] During the process of achieving horizontal crawling in water, the magnetic field with the vertical downward direction is 15-18mT, the duty cycle is 30%, and the driving frequency is 1Hz.

[0030] During the process of achieving underwater propulsive translation: the magnitude of the horizontal magnetic field is 15mT, the driving frequency is 2Hz, the soft robot moves to the right when the duty cycle is adjusted to 75%, and moves to the left when the duty cycle is adjusted to 25%.

[0031] During the process of achieving levitation swimming in water: the magnetic field direction is vertically downward and the magnitude of the magnetic field is 15mT, the driving frequency is 2Hz, and the duty cycle adjustment range is 20-60%.

[0032] During the process of achieving the water jump: the magnetic field direction is vertically downward and the magnitude of the magnetic field is 15mT, the driving frequency is 2Hz, and the duty cycle adjustment range is 0-20%.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] 1. This invention employs a biomimetic structural design, resulting in a soft robot with a jellyfish-inspired double-leg structure. Its central cavity allows for load-bearing or application expansion, offering greater flexibility and adaptability compared to other single-umbrella-shaped soft robots, covering more complex scenarios. The double-leg structure enhances propulsion through coordinated paddling between the upper and lower layers, reducing body sway during movement compared to a single-layer structure. This makes it more suitable for directional movement in slow-flowing or still water, improving underwater mobility and stability. Furthermore, the double-layer design allows for the maintenance of basic movement capabilities even when a single leg fails, reducing the risk of functional failure in extreme environments and enhancing environmental adaptability. Additionally, the magnetization of the support plates in this invention causes the central cavity to deform under the influence of an axial magnetic field, quickly expelling water (or expanding its functionality to include cargo or medication). This, combined with the movement of the surrounding tentacles, enables stable and rapid movement or load-bearing.

[0035] 2. The magnetically controlled soft material prepared in this invention serves as an elastic matrix. This material is easy to prepare; an elastic film can be fabricated simply by dissolving it in a solvent. The process is simple, cost-effective, and offers excellent performance. Furthermore, the elastic matrix exhibits a certain initial tack after film formation. This initial tack enhances micro-adhesion at the contact surface, creating a micro-interlocking effect. By increasing friction, it prevents the robot from slipping relative to the contact surface during magnetic field driving, allowing magnetic energy to be converted into motion displacement more efficiently. In underwater or multi-medium environments, the initial tack resists water flow impacts or medium disturbances, helping the robot stably adhere to the target surface and ensuring the continuity of magnetically controlled motion without requiring additional magnetic field strength.

[0036] 3. This invention uses styrene-isoprene-styrene block copolymer (SIS) as the main elastic matrix of the soft robot. SIS exhibits excellent flexibility and elasticity, possessing high elasticity and deformation recovery capability at room temperature. It is not prone to fatigue cracking after repeated deformation, meeting the flexibility requirements of soft robots. Furthermore, it is simple to process, has high molding efficiency, good environmental stability, and is flexible in modification. By using polybutadiene as a plasticizer, the material's flexibility is improved. The flexible molecular chain and unsaturated bond structure of polybutadiene give it high elasticity, effectively weakening the intermolecular forces of the SIS matrix, reducing the material's hardness and glass transition temperature, while simultaneously enhancing deformation recovery capability and reducing fatigue damage after repeated deformation. By using p-xylene to dissolve the matrix, adjust viscosity, and optimize processing and molding effects, pX, a non-polar aromatic hydrocarbon solvent, exhibits excellent compatibility with SIS, quickly breaking down the intermolecular forces of SIS to form a uniform and stable polymer solution. As a carrier solvent, pX promotes the uniform dispersion of plasticizers and functional fillers in the SIS matrix, avoiding local aggregation. Attached Figure Description

[0037] Figure 1 This is a flowchart illustrating the fabrication process of the magneto-actuated jellyfish-like soft robot described in this invention.

[0038] Figure 2 This is a physical diagram of the magnetic field driving device and a schematic diagram of the magnetic field direction.

[0039] Figure 3 A schematic diagram of the magnetization of the upper and lower support layers;

[0040] Figure 4 This is a schematic diagram of the magnetization of the support sheet;

[0041] Figure 5 A schematic diagram of the overall structure of a magneto-actuated jellyfish-inspired soft robot;

[0042] Figure 6 The stress-strain curves of the thin film materials prepared in the examples and comparative examples are shown.

[0043] Figure 7 The tensile recovery rate of the thin film materials prepared in the examples and comparative examples;

[0044] Figure 8 The bending fatigue test results of the thin film material prepared in the example are shown on the horizontal axis, which represents the number of cycles and the vertical axis represents the bending angle of the thin film.

[0045] Figure 9 The water contact angle of the thin film materials prepared in the examples and comparative examples;

[0046] Figure 10 The acid and alkali resistance of the thin film materials prepared in the examples and comparative examples;

[0047] Figure 11 The magnetic response deformation angles of the thin film materials prepared in the examples and comparative examples are shown.

[0048] Figure 12 The relative relationship between the thickness, magnetic force, and deformation angle of the prepared thin film material;

[0049] Figure 13 A schematic diagram of the structural design of a magneto-actuated jellyfish-inspired soft robot;

[0050] Figure 14 The image shows the gait of a magneto-actuated jellyfish-like soft robot during crawling.

[0051] Figure 15 The image shows the underwater translational gait of a magneto-actuated jellyfish-like soft robot.

[0052] Figure 16 The image shows the underwater jumping and levitation gait of a magneto-actuated jellyfish-like soft robot.

[0053] Figure 17 This is a schematic diagram showing the dimensions of the soft layer and the lower soft layer in Example 1;

[0054] Figure 18 This is a schematic diagram showing the dimensions of the support piece in Example 1. Detailed Implementation

[0055] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. Parts not described or disclosed in detail in the following embodiments of the present invention should be understood as prior art known or should be known by those skilled in the art.

[0056] like Figure 5 As shown, this invention discloses a magnetoactuated jellyfish-like soft robot, comprising an upper soft layer, a lower soft layer, and multiple support plates made of a magnetoactuated soft material. The upper soft layer has N upper tentacles evenly spaced circumferentially along its edge, and the lower soft layer has N lower tentacles evenly spaced circumferentially along its edge. The upper and lower tentacles correspond one-to-one, and the end of each upper tentacle is connected to its corresponding lower tentacle. The upper and lower soft layers are the same size, the ends of the upper tentacles are connected to the middle of the lower tentacles, and the upper tentacles are positioned above the lower tentacles.

[0057] N is an even number and N≥4. N can be 4, 6, 8, 10, etc. Preferably, N=4.

[0058] The upper and lower soft layers are connected by corresponding upper and lower tentacles. Combined with the magnetostrictive properties of the magnetically controlled soft material, this simulates the contraction and propulsion motion of a jellyfish's umbrella-like body. The design of the upper tentacles connecting to the middle of the lower tentacles adds a sense of depth to the deformation of the tentacles under magnetic drive.

[0059] The support plate connects to the upper and lower soft layers at both ends, with the connections located between adjacent upper and lower tentacles, respectively. The upper and lower soft layers are separated by the support plate to form a space capable of accommodating the load. This space can flexibly accommodate micro-sensors, drug delivery modules, micro-drive circuits, etc., upgrading the robot from a single motion carrier to a multi-functional integrated platform, adaptable to complex scenarios such as targeted drug delivery, environmental monitoring, and pipeline inspection.

[0060] The connections between the upper and lower tentacles, as well as between the two ends of the support plate and the upper and lower soft layers, are all bonded. This design simplifies the assembly process, reduces production difficulty, and the bonding process enables seamless connections between components, avoiding motion jamming problems that may occur with mechanical connections, thus maintaining high structural reliability of the robot during repeated magnetostrictive deformation.

[0061] This invention also discloses a method for fabricating a magneto-actuated jellyfish-like soft robot, comprising the following steps:

[0062] S1. The magnetron-controlled soft material is cut to obtain an upper soft layer, a lower soft layer, and a support sheet; wherein, the preparation method of the magnetron-controlled soft material is as follows: styrene-isoprene-styrene block copolymer (SIS), polybutadiene (PBD), and p-xylene (PX) are mixed evenly, and neodymium iron boron (NdFeB) magnetic particles are added to obtain a polymer solution mixed with magnetic particles. The polymer solution mixed with magnetic particles is then spin-coated onto a carrier and dried to obtain a thin film loaded on the carrier. This thin film is the magnetron-controlled soft material.

[0063] S101. Weigh a certain amount of SIS elastic particles and place them in a beaker. Then add liquid PBD and p-xylene solvent in sequence. The weight ratio of SIS elastomer, PBD and p-xylene solvent is 10:1:20.

[0064] S102. After mixing the three components evenly, magnetically stir until the SIS elastic particles are completely dissolved (no white flocculent particles, transparent texture, viscous polymer solution). Add NdFeB magnetic particles to the polymer solution and stir evenly. The weight ratio of NdFeB magnetic particles to SIS elastomer is 1:2.5. SIS is used as the main elastic matrix of soft robots, exhibiting excellent flexibility and elasticity. It possesses high elasticity and deformation recovery capability at room temperature and is not prone to fatigue cracking after repeated deformation, meeting the flexibility requirements of soft robots. It is also simple to process, has high molding efficiency, good environmental stability, and is flexible in modification. It can be blended with various plasticizers and fillers. Hardness, viscosity, and mechanical properties can be precisely controlled through formula adjustment to adapt to different structural design requirements. Polybutadiene, as a plasticizer, can improve the material's flexibility. The flexible molecular chain and unsaturated bond structure of polybutadiene give it high elasticity, which can effectively weaken the intermolecular forces of the SIS matrix, reduce the material's hardness and glass transition temperature, and at the same time improve deformation recovery capability, reducing fatigue damage after repeated deformation. The hardness, viscosity, and mechanical properties of the material can be precisely controlled by adjusting the blending ratio, eliminating the need for additional compatibilizers and simplifying the modification process. PX, a non-polar aromatic hydrocarbon solvent, dissolves the substrate, adjusts viscosity, and optimizes processing and molding effects. It exhibits excellent compatibility with SIS, rapidly breaking down intermolecular forces within SIS to form a uniform and stable polymer solution. As a carrier solvent, PX promotes the uniform dispersion of plasticizers and functional fillers within the SIS matrix, preventing localized aggregation. Neodymium iron boron magnetic particles endow soft robots with magnetic responsiveness, boasting high magnetic energy product, strong coercivity, and excellent cost-effectiveness, precisely matching the performance requirements of flexible actuation.

[0065] S103. Place the polymer solution containing the mixed magnetic particles in a vacuum drying oven for vacuum degassing treatment. The vacuuming time is 10-15 minutes.

[0066] S104. To prepare a magnetoelastic film, a glass slide is used as a carrier. The mixed solution is poured onto the glass slide and spin-coated to prepare the film. A gradient rotation speed is used. First, the film is pre-spread at a low speed of 750-850 rpm for 10-15 seconds, and then the speed is increased to 1150-1250 rpm for 20-25 seconds to reduce the generation of bubbles and improve the uniformity of magnetic particle dispersion.

[0067] S105. Place the spin-coated glass slide on a heated platform for brief drying to accelerate solvent evaporation and rapid film formation. The heating platform temperature is 60-70℃, and the drying time is approximately 5 minutes.

[0068] S106. Then continue with steps S104 and S105 above, perform multiple spin coatings to finally prepare a circular film with a thickness of 0.4-0.5 mm.

[0069] S107. The circular film is cut and trimmed to obtain an upper soft layer, a lower soft layer, and a support sheet. The upper soft layer has N upper tentacles evenly spaced along its circumferential edge, and the lower soft layer has N lower tentacles evenly spaced along its circumferential edge. The upper and lower soft layers are the same size, and the support sheet is rectangular. That is, the upper soft layer includes a sheet-like upper soft layer body and N upper tentacles evenly spaced along its circumferential edge; the lower soft layer includes a sheet-like lower soft layer body and N lower tentacles evenly spaced along its circumferential edge.

[0070] S2. Magnetize the upper soft layer, lower soft layer and support sheet respectively.

[0071] The magnetization direction angles of both the upper and lower soft layers are 45°. For example... Figure 3 , 4 As shown, the magnetic field direction of the magnetization device (i.e., the direction pointing to the N pole) is vertically downward. First, place the upper soft layer horizontally in the magnetization device, keeping the plane of the upper soft layer perpendicular to the magnetic field direction of the magnetization device. Then, adjust each upper tentacle of the upper soft layer downward so that the angle between the upper soft layer and the upper tentacle is 45°, and the angle between the upper tentacle and the magnetic field direction is also 45°. Start the magnetization device to magnetize, that is, the magnetization direction of the upper soft layer is 45°. Similarly, when magnetizing the lower soft layer, keep the magnetic field direction of the magnetization device vertically downward. First, place the lower soft layer horizontally in the magnetization device, keeping the plane of the lower soft layer perpendicular to the magnetic field direction of the magnetization device. Then, adjust each lower tentacle of the lower soft layer downward so that the angle between the lower soft layer and the lower tentacle is 45°, and the angle between the lower tentacle and the magnetic field direction is also 45°. Start the magnetization device to magnetize, that is, the magnetization direction angle of the lower soft layer is 45°.

[0072] The support sheet is folded in half and then magnetized, with the folded support sheet perpendicular to the direction of the magnetic field. For example... Figure 5 As shown, the magnetic field of the magnetizing device is vertically downward. After folding the support plate in half, place it horizontally in the magnetizing device and start the magnetizing device to magnetize.

[0073] S3. After magnetization, the upper soft layer, lower soft layer, and support sheet are bonded together. The bottom surface of each upper tentacle end is bonded to the surface of its corresponding lower tentacle end. The two ends of the support sheet are bonded to the bottom surface of the upper soft layer body and the surface of the lower soft layer body, respectively. For ease of description, during the magnetization process, the side of the upper and lower soft layers facing the S pole is considered its surface, and the side facing the N pole is considered its bottom surface. The support sheet is folded into a U-shape, with the outer edge of the U-shaped support sheet being its outer surface and the inner edge being its inner surface. During bonding, the upper and lower soft layers are arranged vertically, with the bottom surface of the upper soft layer facing the surface of the lower soft layer. The bottom surface of the upper tentacle's end is connected to the end surface of the lower tentacle. The upper and lower soft layers are separated by a support plate to form a space capable of accommodating a load. The two ends of the support plate are connected to the bottom surface of the upper soft layer body and the surface of the lower soft layer body, respectively, and the inner surface of the support plate faces the formed space capable of accommodating a load, thus obtaining the magnetoactuated jellyfish-like soft robot. Figure 13 As shown.

[0074] This invention employs a biomimetic structural design to create a magnetoactuated jellyfish-like soft robot with a double-legged structure. Its central cavity can be used for load-bearing functions or application expansion. Compared with other soft robots with a single umbrella-shaped structure, its application scenarios are more flexible and adaptable, and it can cover more complex scenario requirements.

[0075] The magneto-actuated jellyfish-like soft robot designed in this invention has multiple modes of motion, can adapt to both terrestrial and aquatic environments, and possesses adaptability to complex environments.

[0076] When a soft robot is placed in a magnetic field pointing vertically downwards, it can achieve horizontal crawling motion under the influence of the magnetic field gradient force. Its maximum crawling speed on land is 11.77 mm / s, and its fastest crawling speed in water is 5.33 mm / s.

[0077] By placing the soft robot in a magnetic field that is horizontally oriented to the left, and then applying alternating left and right magnetic fields, the soft robot can achieve propulsive left and right translational motion in water by adjusting the drive frequency and duty cycle.

[0078] By adding a buoyancy module and adjusting the overall density of the soft robot, and placing it in a magnetic field with the magnetic field direction pointing vertically downwards, the soft robot can achieve levitation in water and propulsive up-and-down jumping and undulating movements by adjusting the drive frequency and duty cycle.

[0079] This invention also discloses a driving method for a magneto-actuated jellyfish-like soft robot, comprising at least the following:

[0080] 1) The magneto-actuated jellyfish-like soft robot is placed on land and a magnetic field with a vertical downward direction is applied to achieve horizontal crawling on land. During the horizontal crawling process, the magnitude of the magnetic field with a vertical downward direction is 18mT, the driving frequency is 2.5Hz, and the duty cycle is 30%.

[0081] 2) Place the magneto-actuated jellyfish-like soft robot on land and apply a horizontal magnetic field to achieve horizontal rolling on land. During the horizontal rolling process, the horizontal magnetic field is 15-18 mT, the duty cycle is 50%, and the driving frequency is 1 Hz.

[0082] 3) Place the magneto-actuated jellyfish-like soft robot in water and apply a magnetic field with the direction of vertical downward to achieve horizontal crawling in water. During the horizontal crawling process, the magnetic field with the direction of vertical downward is 15-18mT, the duty cycle is 30%, and the driving frequency is 1Hz.

[0083] 4) Place the magneto-actuated jellyfish-like soft robot in water and apply a horizontal magnetic field to achieve underwater propulsion translation. During the underwater propulsion translation process: the magnitude of the horizontal magnetic field is 15mT, the driving frequency is 2Hz, the soft robot moves to the right when the duty cycle is adjusted to 75%, and the soft robot moves to the left when the duty cycle is adjusted to 25%.

[0084] 5) First, adjust the overall density of the magneto-actuated soft robot to be greater than that of water. Then, place the magneto-actuated jellyfish-like soft robot in the water and apply a magnetic field with the direction of vertical downward to achieve levitation and swimming in the water. During the process of achieving levitation and swimming in the water, the magnitude of the magnetic field with the direction of vertical downward is 15mT, the driving frequency is 2Hz, and the duty cycle adjustment range is 20-60%.

[0085] 6) First, adjust the overall density of the magneto-actuated soft robot to be greater than that of water. Then, place the magneto-actuated jellyfish-like soft robot in the water and apply a vertically downward magnetic field to achieve water jumping. During the water jumping process: the magnitude of the vertically downward magnetic field is 15mT, the driving frequency is 2Hz, and the duty cycle adjustment range is 0-20%.

[0086] Example 1

[0087] A method for fabricating a magnetoactuated jellyfish-inspired soft robot, such as... Figure 1 As shown, it includes the following steps:

[0088] 1. Weigh 1g of SIS elastic particles into a beaker, then add 0.1g of liquid PBD and 2g of p-xylene solvent in sequence.

[0089] 2. After mixing the three ingredients evenly, stir magnetically until the SIS elastic particles are completely dissolved (no white flocculent particles, transparent texture, and viscous polymer solution) to obtain a polymer solution. Add 2.5g of NdFeB magnetic particles to the polymer solution and stir evenly to obtain a polymer solution mixed with magnetic particles.

[0090] 3. Place the polymer solution containing the mixed magnetic particles in a vacuum drying oven for vacuum degassing treatment for 10 minutes.

[0091] 4. Pour the polymer solution containing the mixed magnetic particles onto a glass slide and spin-coat it to prepare a thin film. Use a gradient spin-coating speed. First, pre-spread at a low speed of 800 rpm for 15 seconds, and then increase to a high speed of 1200 rpm for 25 seconds to reduce the generation of bubbles and improve the uniformity of magnetic particle dispersion.

[0092] 5. Place the spin-coated glass slide on a heated platform for brief drying to accelerate solvent evaporation and rapid film formation. The heating platform temperature is 65℃, and the drying time is 5 minutes.

[0093] 6. Then continue with steps 4 and 5 above, and perform spin coating multiple times. After each spin coating, use a vernier caliper to measure the film thickness. Finally, a circular film with a thickness of 0.5 mm is prepared. This circular film is the magnetron soft material.

[0094] 7. Cut the circular film to obtain the upper soft layer, lower soft layer, and support sheet. The dimensions of the upper and lower soft layers are as follows: Figure 17 As shown, the thickness is 0.5mm, and there are four upper and four lower tentacles, all of which are trapezoidal pieces. The end width of the upper and lower tentacles is 5mm, and the width of the connection between them and the corresponding upper and lower soft body layers is 10mm. The dimensions of the support piece are as follows. Figure 18 As shown, the thickness is 0.5mm, the width is 5mm, and the length is 20mm.

[0095] It is then placed in a magnetizer for magnetization. The magnetization direction angle of the upper and lower soft layers is 45°, and the magnetization direction of the four-sided support plate is folded in half and then magnetized vertically downward along the plane (at 90° with the plane).

[0096] 8. The overall structure is divided into upper and lower layers and four-sided support. After magnetization, it is glued and assembled. Double-sided adhesive or silicone adhesive is used for bonding. Finally, a magneto-actuated jellyfish-like soft robot with a double-layer leg structure is prepared.

[0097] Example 2

[0098] A method for fabricating a magnetoactuated jellyfish-inspired soft robot includes the following steps:

[0099] 1. Weigh 1g of SIS elastic particles into a beaker, then add 0.07g of liquid PBD and 25g of p-xylene solvent in sequence.

[0100] 2. After mixing the three ingredients evenly, stir magnetically until the SIS elastic particles are completely dissolved (no white flocculent particles, transparent texture, and viscous polymer solution) to obtain a polymer solution. Add 2g of NdFeB magnetic particles to the polymer solution and stir evenly to obtain a polymer solution mixed with magnetic particles.

[0101] 3. Place the polymer solution containing the mixed magnetic particles in a vacuum drying oven for vacuum degassing treatment for 10 minutes.

[0102] 4. Pour the polymer solution containing the mixed magnetic particles onto a glass slide and spin-coat it to prepare a thin film. Use a gradient spin-coating speed. First, pre-spread at a low speed of 750 rpm for 10 seconds, and then increase to a high speed of 1150 rpm for 22 seconds to reduce bubble generation and improve the uniformity of magnetic particle dispersion.

[0103] 5. Place the spin-coated glass slide on a heated platform for brief drying to accelerate solvent evaporation and rapid film formation. The heating platform temperature is 65℃, and the drying time is 5 minutes.

[0104] 6. Then continue with steps 4 and 5 above, performing spin coating multiple times. After each spin coating, use vernier calipers to measure the film thickness, and finally prepare a circular film with a thickness of 0.4 mm.

[0105] 7. Cut the circular film to obtain an upper soft layer, a lower soft layer, and a support sheet. Both the upper and lower layers have six tentacles.

[0106] It is then placed in a magnetizer for magnetization. The magnetization direction angle of the upper and lower soft layers is 45°, and the magnetization direction of the four-sided support plate is folded in half and then magnetized vertically downward along the plane (at 90° with the plane).

[0107] 8. The overall structure is divided into upper and lower layers and four-sided support. After magnetization, it is glued and assembled. Double-sided adhesive or silicone adhesive is used for bonding. Finally, a magneto-actuated jellyfish-like soft robot with a double-layer leg structure is prepared.

[0108] Example 3

[0109] A method for fabricating a magnetoactuated jellyfish-inspired soft robot includes the following steps:

[0110] 1. Weigh 1g of SIS elastic particles into a beaker, then add 0.12g of liquid PBD and 3g of p-xylene solvent in sequence.

[0111] 2. After mixing the three ingredients evenly, stir magnetically until the SIS elastic particles are completely dissolved (no white flocculent particles, transparent texture, and viscous polymer solution) to obtain a polymer solution. Add 2.2g of NdFeB magnetic particles to the polymer solution and stir evenly to obtain a polymer solution mixed with magnetic particles.

[0112] 3. Place the polymer solution containing the mixed magnetic particles in a vacuum drying oven for vacuum degassing treatment for 10 minutes.

[0113] 4. Pour the polymer solution containing the mixed magnetic particles onto a glass slide and spin-coat it to prepare a thin film. Use a gradient spin-coating speed. First, pre-spread at a low speed of 850 rpm for 12 seconds, and then increase to a high speed of 1250 rpm for 20 seconds to reduce bubble generation and improve the uniformity of magnetic particle dispersion.

[0114] 5. Place the spin-coated glass slide on a heated platform for brief drying to accelerate solvent evaporation and rapid film formation. The heating platform temperature is 65℃, and the drying time is 5 minutes.

[0115] 6. Then continue with steps 4 and 5 above, performing spin coating multiple times. After each spin coating, use vernier calipers to measure the film thickness, and finally prepare a circular film with a thickness of 0.45 mm.

[0116] 7. Cut the circular film to obtain an upper soft layer, a lower soft layer, and a support sheet. Both the upper and lower layers have eight tentacles.

[0117] It is then placed in a magnetizer for magnetization. The magnetization direction angle of the upper and lower soft layers is 45°, and the magnetization direction of the four-sided support plate is folded in half and then magnetized vertically downward along the plane (at 90° with the plane).

[0118] 8. The overall structure is divided into upper and lower layers and four-sided support. After magnetization, it is glued and assembled. Double-sided adhesive or silicone adhesive is used for bonding. Finally, a magneto-actuated jellyfish-like soft robot with a double-layer leg structure is prepared.

[0119] Example 4

[0120] A driving method for a magneto-actuated jellyfish-like soft robot involves placing the magneto-actuated jellyfish-like soft robot prepared in Example 1 on land and applying a vertically downward magnetic field to achieve horizontal crawling on land. Figure 2The image shows a physical diagram of the magnetic field drive device and a schematic diagram of the magnetic field direction. During the horizontal crawling process on land, the magnetic field with a vertically downward direction has a magnitude of 18 mT, a drive frequency of 2.5 Hz, a duty cycle of 30%, and a movement speed of 11.77 mm / s.

[0121] Tests showed that the crawling gait of horizontal crawling on land is as follows: Figure 14 As shown.

[0122] Example 5

[0123] A driving method for a magneto-actuated jellyfish-like soft robot involves placing the magneto-actuated jellyfish-like soft robot prepared in Example 1 on land and applying a horizontal magnetic field to achieve horizontal rolling on land. During the horizontal rolling process, the horizontal magnetic field is 18 mT, the driving frequency is 1 Hz, and the duty cycle is 50%.

[0124] Example 6

[0125] A driving method for a magneto-actuated jellyfish-like soft robot involves placing the magneto-actuated jellyfish-like soft robot prepared in Example 1 in water and applying a magnetic field with a vertically downward direction to achieve horizontal crawling in the water. During the horizontal crawling process, the magnetic field with a vertically downward direction is 18mT, the duty cycle is 30%, the driving frequency is 1Hz, and the movement speed is 5.33mm / s.

[0126] Tests showed that the crawling gait of horizontal movement in water is as follows: Figure 14 As shown.

[0127] Example 7

[0128] A driving method for a magnetoacted jellyfish-inspired soft robot involves placing the robot (prepared in Example 1) in water and applying a horizontal magnetic field to achieve underwater propulsive translation. During this underwater propulsive translation, the horizontal magnetic field strength is 15 mT, the driving frequency is 2 Hz, and the robot translates to the right when the duty cycle is adjusted to 75%, and to the left when the duty cycle is adjusted to 25%. Specifically, when the duty cycle is 0%, the magnetic field direction is always to the right. When the duty cycle is adjusted to 25%, the ratio of right to left time within one cycle is 75:25, and the soft robot oscillates and translates to the left under the influence of the magnetic field force. When the duty cycle is 100%, the magnetic field direction is always to the left. When the duty cycle is adjusted to 75%, the ratio of right to left time within one cycle is 25:75, and the soft robot oscillates and translates to the right under the influence of the magnetic field force.

[0129] The alternating magnetic field is controlled by a microcontroller that controls the on / off state of a relay, thereby controlling the direction of the current flowing into the coil and achieving the switching of the magnetic field direction. The time ratio of the left and right alternating magnetic fields is achieved by adjusting the duty cycle.

[0130] The underwater translational gait of this magneto-actuated jellyfish-like soft robot is as follows: Figure 15 As shown.

[0131] Example 8

[0132] A driving method for a magneto-actuated jellyfish-like soft robot involves first adjusting the overall density of the magneto-actuated soft robot prepared in Example 1 to be greater than that of water by adding a buoyancy module. Then, the magneto-actuated jellyfish-like soft robot is placed in water, and a vertically downward magnetic field is applied to achieve suspension and jumping in the water. The buoyancy module is white foam with a mass of 0.012g. The buoyancy module is fixed to the upper part of the upper soft layer body by adhesive bonding.

[0133] During the process of achieving levitation swimming in water: the magnetic field direction is vertically downward with a magnitude of 15mT, the driving frequency is 2Hz, and the duty cycle is 50%.

[0134] Example 9

[0135] This embodiment is used to drive a magneto-actuated jellyfish-like soft robot to achieve jumping motion in water. The overall steps are the same as those in embodiment 8, except that the magnetic field direction is vertically downward and the magnitude of the magnetic field is 15mT, the driving frequency is 2Hz, and the duty cycle is 20%.

[0136] Testing revealed that the magnetically actuated jellyfish-like soft robot exhibited excellent underwater jumping, levitation, and swimming gait. Figure 16 As shown.

[0137] Comparative Example 1

[0138] The process of preparing the magneto-controlled soft material in this embodiment is generally the same as that in Example 1, except that the addition ratio of SIS, PBD and NdFeB powder in this comparative example is 10:0:5.

[0139] Comparative Example 2

[0140] The process of preparing the magneto-controlled soft material in this embodiment is generally the same as that in Example 1, except that the addition ratio of SIS, PBD and NdFeB powder in this comparative example is 10:0.5:15.

[0141] Comparative Example 3

[0142] The process of preparing the magneto-controlled soft material in this embodiment is generally the same as that in Example 1, except that the addition ratio of SIS, PBD and NdFeB powder in this comparative example is 10:0:15.

[0143] Comparative Example 4

[0144] The process of preparing the magneto-controlled soft material in this embodiment is generally the same as that in Example 1, except that the addition ratio of SIS, PBD and NdFeB powder in this comparative example is 10:0.5:25.

[0145] Comparative Example 5

[0146] The process of preparing the magneto-controlled soft material in this embodiment is generally the same as that in Example 1, except that the addition ratio of SIS, PBD and NdFeB powder in this comparative example is 10:1:5.

[0147] Comparative Example 6

[0148] The process of preparing the magneto-controlled soft material in this embodiment is generally the same as that in Example 1, except that the addition ratio of SIS, PBD and NdFeB powder in this comparative example is 10:0:25.

[0149] Comparative Example 7

[0150] The process of preparing the magneto-controlled soft material in this embodiment is generally the same as that in Example 1, except that the addition ratio of SIS, PBD and NdFeB powder in this comparative example is 10:0.5:5.

[0151] Comparative Example 8

[0152] The process of preparing the magneto-controlled soft material in this embodiment is generally the same as that in Example 1, except that the addition ratio of SIS, PBD and NdFeB powder in this comparative example is 10:1:15.

[0153] Below, the performance of the magnetically controlled soft material film prepared in Example 1 of this invention is tested as the elastic substrate (hereinafter referred to as the elastic substrate) of the magnetoacted jellyfish-like soft robot, and the performance of the elastic substrate and the films prepared in Comparative Examples 1-8 are tested. In the magnetically controlled soft material film prepared in Example 1, the addition ratio of SIS, PBD and NdFeB powder is 10:1:25.

[0154] <Mechanical Properties>

[0155] like Figure 6 As shown, the elastic matrix has excellent elasticity and toughness. The addition of PBD reduces the elastic modulus of the elastic matrix, enabling the soft robot to meet the requirements of high elasticity and large deformation.

[0156] <Fatigue resistance>

[0157] like Figure 7 , 8 As shown, the elastic matrix was subjected to tensile strain of 200% for 1 min, 10 min, and 10 h, and the tensile recovery rate was observed. It was found that the elastic recovery rate remained at about 95%, indicating that the elastic matrix has excellent tensile recovery performance.

[0158] The elastic matrix was placed in an alternating magnetic field environment of 10 mT. After nearly 10,000 cycles of bending tests, the bending angle remained within the effective range. No adverse phenomena such as significant degradation of bending performance or fatigue fracture were observed during the test, indicating that the elastic matrix has excellent fatigue resistance and can stably adapt to repeated deformation scenarios.

[0159] <Environmental stability>

[0160] like Figure 9 , 10 As shown, the water contact angle of the elastic matrix surface is 99°. After being immersed in liquid environments with pH=4.5, pH=7, and pH=11.5 for 96 hours, the weight change rate is within the range of 5%, indicating that it has hydrophobic properties and acid and alkali resistance, and excellent environmental adaptability.

[0161] <Magneelastic Properties>

[0162] like Figure 11 , 12 As shown, the elastic matrix can achieve maximum deformation under a magnetic field strength of 15 mT, exhibiting excellent magnetoelastic properties and rapid magnetic response. Furthermore, films with thicknesses of 0.25 mm and 0.75 mm were prepared using the method of this invention. Testing revealed that when the film thickness was 0.5 mm, the magnetic force and bending angle achieved a relative balance, ensuring both stable magnetic performance and good deformation properties, thus achieving a highly efficient balance between the two.

[0163] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A magnetically actuated jellyfish-like soft robot, characterized in that, The magnetic actuated jellyfish-like soft robot comprises an upper soft layer, a lower soft layer and a plurality of support pieces made of a magnetic soft material, edges of the upper soft layer are uniformly spaced in a circumferential direction and provided with N upper tentacles, edges of the lower soft layer are uniformly spaced in a circumferential direction and provided with N lower tentacles, the upper tentacles and the lower tentacles correspond to each other, and an end of each upper tentacle is connected to a corresponding lower tentacle, N is an even number and N is greater than or equal to 4; two ends of the support piece are connected to the upper soft layer and the lower soft layer respectively, and the connection positions are located between adjacent upper tentacles and adjacent lower tentacles respectively, and the upper soft layer and the lower soft layer are separated from each other by the support of the support piece to form a space capable of accommodating a load.

2. The magnetically actuated jellyfish-like soft robot of claim 1, wherein, The upper soft layer and the lower soft layer have the same size.

3. The magnetically actuated jellyfish-like soft robot of claim 1, wherein, N＝4。 4. A method of manufacturing the magnetic actuated jellyfish soft robot of claim 1, wherein, The method comprises the following steps: S1, cutting the magnetic soft material to obtain the upper soft layer, the lower soft layer and the support piece as claimed in claim 1; S2, magnetizing the upper soft layer, the lower soft layer and the support piece respectively, wherein the magnetizing direction angle of the upper soft layer and the lower soft layer is 45°, and the support piece is magnetized after being folded, and the folded support piece is perpendicular to the direction of the magnetic field; S3, bonding the magnetized upper soft layer, lower soft layer and support piece, bonding the end of each upper tentacle and the corresponding lower tentacle, and bonding the two ends of the support piece to the upper soft layer and the lower soft layer respectively, to obtain the magnetic actuated jellyfish-like soft robot.

5. The method of claim 4, wherein the method further comprises: The preparation method of the magnetic soft material comprises the following steps: uniformly mixing styrene-isoprene-styrene block copolymer, polybutadiene and p-xylene, adding neodymium-iron-boron magnetic particles to obtain a polymer solution mixed with the magnetic particles, spin coating the polymer solution mixed with the magnetic particles onto a carrier, and drying to obtain a thin film loaded on the carrier, which is the magnetic soft material.

6. The method of claim 4, wherein the magnetic actuation jellyfish soft robot is prepared by the steps of: providing a substrate; providing a magnetic material; providing a polymer material; providing a magnetic field; and providing a magnetic field gradient. In step S1, the polymer solution mixed with the magnetic particles is spin coated onto the carrier at a gradient speed, dried, spin coated again, dried, and repeated multiple times to obtain a thin film loaded on the carrier, and the thickness of the thin film is 0.4-0.5mm; The gradient speed is specifically: first, pre-spread at a low speed of 750-850rpm for 10-15s, and then spread at a high speed of 1150-1250rpm for 20-25s.

7. The method of claim 4, wherein the magnetic actuation jellyfish soft robot is prepared by the steps of: providing a substrate; providing a magnetic material; providing a polymer material; providing a magnetic field; and providing a magnetic field gradient. In step S1, the weight ratio of the styrene-isoprene-styrene block copolymer and the polybutadiene is 10:0.7-1.2:20-30; and the weight ratio of the neodymium-iron-boron magnetic particles to the styrene-isoprene-styrene block copolymer is 1:2-2.

5.

8. A method of driving the magnetic actuated jellyfish soft robot of claim 1, wherein, The method comprises the following steps: Placing the magnetic actuated jellyfish-like soft robot on land and applying a magnetic field with a vertical downward direction to realize horizontal crawling on land; Or, placing the magnetic actuated jellyfish-like soft robot on land and applying a horizontal magnetic field to realize horizontal rolling on land; Or, placing the magnetic actuated jellyfish-like soft robot in water and applying a magnetic field with a vertical downward direction to realize horizontal crawling in water; Or, placing the magnetic actuated jellyfish-like soft robot in water and applying a horizontal magnetic field to realize horizontal translation by pushing in water; Or, first adjusting the overall density of the magnetic actuated soft robot to be greater than water, then placing the magnetic actuated jellyfish-like soft robot in water and applying a magnetic field with a vertical downward direction to realize suspended swimming and jumping in water.

9. A driving method for a magnetoactuated jellyfish-like soft robot as described in claim 8, characterized in that, The overall density of the magnetic actuated soft robot is adjusted by adding the buoyancy module, and the mass ratio of the buoyancy module to the magnetic actuated soft robot is 1:155-165.

10. A driving method for a magnetoactuated jellyfish-like soft robot as described in claim 8, characterized in that, In the process of realizing land horizontal crawling, the magnetic field size is 18 mT, the driving frequency is 2.5 Hz, and the duty cycle is 30% when the magnetic field direction is vertically downward. In the process of realizing land horizontal rolling, the magnetic field is 15-18 mT, the duty cycle is 50%, and the driving frequency is 1 Hz when the magnetic field direction is horizontal. In the process of realizing horizontal crawling in water, the magnetic field is 15-18 mT, the duty cycle is 30%, and the driving frequency is 1 Hz when the magnetic field direction is vertically downward. In the process of realizing water propulsion translation, the magnetic field size is 15 mT, the driving frequency is 2 Hz, and the soft robot moves to the right when the duty cycle is adjusted to 75%, and the soft robot moves to the left when the duty cycle is adjusted to 25%. In the process of realizing water suspension swimming, the magnetic field size is 15 mT, the driving frequency is 2 Hz, and the duty cycle adjustment interval is 20-60% when the magnetic field direction is vertically downward. In the process of realizing water jumping, the magnetic field size is 15 mT, the driving frequency is 2 Hz, and the duty cycle adjustment interval is 0-20% when the magnetic field direction is vertically downward.

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