Preparation process and control method of free curvature bionic artificial muscle fan blade

Abstract

The invention discloses a preparation process and a control method of a free-curvature bionic artificial muscle fan blade, and belongs to the technical field of bionic artificial muscle fan blades. Natural high-molecular polymer sodium alginate and ionic liquid are mixed to prepare a biomass gel electric actuating membrane with high output force density and high strength at normal temperature; the biomass gel conductive ink prepared by blending the gallium-indium-tin alloy and the sodium alginate powder is used as the electrode film, and the formed artificial muscle fan blade is high in energy conversion rate, small in starting voltage, high in response speed and capable of having higher structural strength at normal temperature. And finally, the sector electrode is divided into a plurality of areas, and power can be independently supplied to control the curvature effect. According to the preparation process and the control method of the free curvature bionic artificial muscle fan blade adopting the structure, the production process is simple, the structure is stable, deformation is rapid, controllability is high, and a new thought is provided for research and application expansion of artificial muscle devices.

Description

Technical Field

[0001] The invention relates to the technical field of bionic artificial muscle fan blades, and in particular to a preparation process and a control method of a free curvature bionic artificial muscle fan blade. Background Art

[0002] When it is necessary to obtain power in the fluid, the existing drive methods mostly use axial flow propellers, but the design of the blades requires complex aerodynamic calculations, and once finalized, they have their own optimal working speed and direction. In the actual operation of most equipment, it is inevitable that they will need to operate at non-optimal speeds for a long time, resulting in energy waste due to inefficiency. Therefore, the development of a simple, practical, and freely adjustable curvature aerodynamic fan blade that can adapt to different speed ranges to improve the efficiency and capacity of axial flow propellers and to assist in research is of great value and significance for advancing the development of the field of air and underwater exploration. Summary of the invention

[0003] The purpose of the present invention is to provide a preparation process and control method of a free curvature bionic artificial muscle blade, which has a clear principle, simple operation and universal applicability. At the same time, the optimal construction material ratio and process parameters according to the process are provided, thereby obtaining a biomass gel artificial muscle blade with high response efficiency, fast deformation rate, free curvature change and self-shaping.

[0004] To achieve the above object, the present invention provides a preparation process and control method of a free curvature bionic artificial muscle fan blade, comprising the following steps:

[0005] S1: preparing a bionic artificial muscle fan blade electro-actuated membrane solution; weighing 4 g of sodium alginate, adding 200 mL of distilled water into a beaker, pouring in sodium alginate powder to completely dissolve it, adding 6 mL of propylene glycol and 4 mL of ionic liquid, and stirring until the solution presents a colorless gel-like substance without solid particles or flocs; then subjecting the solution to ultrasonic treatment for 10 minutes to remove bubbles, thereby obtaining a bionic artificial muscle fan blade electro-actuated membrane solution;

[0006] S2: Prepare the electrode membrane biomass conductive ink; weigh the sodium alginate powder and put it into a watch glass, inject the high melting point gallium indium tin alloy into it, heat and melt the gallium indium tin alloy, use a glass rod to stir so that the sodium alginate powder is completely covered by the gallium indium tin alloy, and present a silver colloid state, then transfer it to a beaker, add 50 ml of distilled water and ultrasonically disperse it for 30 minutes, and stir at 60°C for 1 hour to obtain the biomass conductive ink used for artificial muscle fan blades;

[0007] S3: preparing an actuated membrane fan blade with a self-heating function; using a 3D printer to print a designed fan blade-shaped mold with ABS as the material, setting up the heating wire according to the preset shape in the mold, and then pouring the bionic artificial muscle fan blade electro-actuated touch solution obtained in step S1 into the mold, and drying it at a constant temperature of 60° C. in a vacuum drying oven for 48 hours to obtain the main part of the artificial muscle fan blade;

[0008] S4: Printing the driving electrodes of the artificial muscle blades; pouring the biomass conductive ink obtained in step S2 into the slurry tank of the clay printer, placing the main part of the biomass gel artificial muscle blade obtained in step S3 into a customized positioning mold so that its upper plane is flush with the top surface of the mold; placing the mold on the base of the clay printer, printing the shape of the upper surface electrode on the artificial muscle blade actuation membrane according to the pre-programmed shape, and filling the contact surface for connecting the circuit at the tail of the artificial muscle, placing it in a drying oven for drying, and repeating 5 times to obtain the top electrode membrane; then inverting the blade and repeating the above steps to make the bottom electrode membrane;

[0009] S5: Replace the biomass conductive ink with the electro-actuated membrane solution of the bionic artificial muscle fan blade, and use a clay printer to fill the gap between the electrode membrane with the electro-actuated membrane solution to ensure the integrity of the fan blade; finally, wrap the obtained bionic artificial muscle fan blade with polyvinyl chloride film, and put it into a vacuum packaging machine for packaging to obtain a bionic artificial muscle fan blade with both rigidity and flexibility and self-adjusting curvature.

[0010] Preferably, in step S1, the dissolution conditions of sodium alginate added to distilled water are heating in a water bath at 60° C. and stirring at a constant speed of 800 r / min.

[0011] Preferably, in step S2, 2 g of sodium alginate powder is taken, 2 mL of liquid gallium indium tin alloy is taken and mixed with the sodium alginate powder, and the mixture is heated in a water bath to maintain the temperature at 55° C., so that the sodium alginate powder is completely coated with the gallium indium tin alloy.

[0012] A control method for a free-curvature bionic artificial muscle fan blade, wherein each of the eight electrodes connected to the root of the fan blade electrode membrane is numbered 1-8, and pairs of No. 1 and No. 8, No. 2 and No. 7, and No. 3 and No. 6 are the electrode power-on areas, and the required voltage and direction need to be applied according to the programming; No. 4 and No. 5 are the heating wire power-on areas, which can be connected to the positive and negative poles of the power supply.

[0013] Preferably, when the fan blade is heated, before all deformation strategies are implemented, the fan blade is heated as a whole to soften the electrode membrane and the actuator membrane, and regions 4 and 5 are connected to the positive and negative poles of the power supply.

[0014] Preferably, the curling of the outer fan blades is controlled: when the fan blades need to be concave downward, area 1 is connected to the positive pole of the power supply, and area 8 is connected to the negative pole of the power supply; when the fan blades need to be convex upward, area 1 is connected to the negative pole of the power supply, and area 8 is connected to the positive pole of the power supply.

[0015] Preferably, the curling of the middle fan blades is controlled: when the middle part of the fan blades needs to be concave downward, area 2 is connected to the positive pole of the power supply, and area 7 is connected to the negative pole of the power supply; when the fan blades need to be convex upward, area 1 is connected to the negative pole of the power supply, and area 8 is connected to the positive pole of the power supply.

[0016] Preferably, the curling of the inner fan blade is controlled: when the inner side of the fan blade is concave downward, area 3 is connected to the positive pole of the power supply, and area 6 is connected to the power supply; when the inner side of the fan blade is convex upward, area 3 is connected to the negative pole of the power supply, and area 6 is connected to the positive pole of the power supply.

[0017] Therefore, the present invention adopts a preparation process and control method of a free curvature bionic artificial muscle fan blade of the above structure, which has the advantages of:

[0018] First, the addition of ionic liquids with a large molecular weight difference between anions and cations enables bionic artificial muscles to achieve higher output force density and service life. At the same time, compared with traditional viscoelastic bionic artificial muscle materials, the high melting point of [EM Im][BF4] gives the bionic artificial muscle a higher structural strength at room temperature. High-melting-point gallium indium tin alloy is added to the bionic artificial muscle electrode membrane to replace carbon nanotubes. Compared with traditional electrode membranes, liquid metal has higher conductivity and liquid fluidity at high temperatures, which greatly reduces the need for bionic artificial muscles to overcome their own viscoelastic force during output, making it have higher energy conversion efficiency. Its solidification characteristics at room temperature work together with [EM Im][BF4] to enable artificial muscles to have the ability to cool down and set after reaching a specific shape, thereby avoiding the reduction in life caused by long-term work of artificial muscles.

[0019] Second, compared to traditional metal or plastic blades, using bionic artificial muscles as blades will make them more flexible. Traditional blades have a fixed shape, and their energy efficiency curve and wind pressure-speed curve are fixed. They are only suitable for specific occasions, and a lot of energy will be lost in situations where reverse thrust is required. The curvature of the bionic artificial muscle blades can be changed at will and can achieve the effect of flipping the blades. This design allows the propeller using bionic artificial muscles to adapt to different speed ranges while having the best energy efficiency curve, and can meet the requirements of efficient propulsion in both forward and reverse directions.

[0020] Third, the electrode design is divided into zones, and the electrode is constructed by 3D printing additive manufacturing. The repeated casting process allows the interfaces of each part to adhere well, so that the artificial muscle blade has good integrity, and the electrode shape can be freely customized according to needs. This allows the bionic artificial muscle blade to have more surface curvature options, which is helpful for the study of fluid dynamics, expands the choice of energy-saving thrusters, and provides new ideas for the future development of artificial muscles.

[0021] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the artificial muscle fan blade of the present invention.

[0023] Figure 2 It is an enlarged view of the powered area at the bottom of the artificial muscle fan blade of the present invention.

[0024] Figure 3 It is a schematic diagram of the artificial muscle fan blade of the present invention after being assembled.

[0025] Figure 4 This is the power-on area division of the artificial muscle fan blade electric drive control strategy of the present invention.

[0026] Figure 5 It is a schematic diagram of the electrical control of the heating behavior of the artificial muscle fan blade of the present invention.

[0027] Figure 6 It is a schematic diagram of the outer blade bending electrical control strategy of the artificial muscle blade electrical drive control strategy of the present invention.

[0028] Figure 7 It is a schematic diagram of the electric control strategy for the bending of the middle blade of the artificial muscle blade electric drive control strategy of the present invention.

[0029] Figure 8 It is a schematic diagram of the inner blade bending electrical control strategy of the artificial muscle blade electrical drive control strategy of the present invention.

[0030] Figure numerals: 1. Main body of artificial muscle fan blade; 2. Electrode membrane; 3. Bionic artificial muscle fan blade electro-actuated membrane solution. DETAILED DESCRIPTION

[0031] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two.

[0033] It should also be noted that the term "includes", "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that a commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the commodity or device including the elements.

[0034] Example 1

[0035] The preparation of a free curvature bionic artificial muscle blade can be divided into the following main processes: preparing a biomass gel artificial muscle blade actuating membrane solution, preparing a biomass gel conductive ink, constructing a biomass gel artificial muscle blade mold to prepare an actuating membrane and pre-embed a heating wire, printing a biomass gel artificial muscle electrode, and repairing and packaging the biomass gel artificial muscle blade. Using 3D printing stacking technology, the device has high integrity, higher customization freedom, and greatly reduced operational difficulty.

[0036] Preparation of biomass gel artificial muscle blade actuation membrane solution

[0037] Measure 200mL of distilled water in a 200mL beaker, put it into a water bath magnetic stirrer, set the temperature to 60℃ and stir at a constant temperature. After the temperature in the beaker reaches 60℃, use an analytical balance to weigh 4g of sodium alginate, then increase the speed of the magnetic stirrer to make the liquid surface of the beaker vortex-shaped. At this time, add a small amount of weighed sodium alginate powder along the wall of the cup quickly to make it evenly dispersed to avoid agglomeration. After all are added, adjust the speed of the magnetic stirrer to 800r / min. After continuous stirring for 1h, the solution is a colorless gel, without solid particles and flocculants. Then put the beaker into an ultrasonic cleaner for about 10min to remove bubbles, and you can get the biomass gel bionic artificial muscle fan blade actuation membrane solution 3.

[0038] Preparation of electrode membrane biomass gel conductive ink

[0039] Weigh 2g of sodium alginate powder and place it in an evaporating dish. At the same time, take an appropriate amount of gallium indium tin alloy solid in a beaker and heat it in a water bath at 55°C. After it is completely melted, use a medical syringe to measure 2mL of liquid gallium indium tin alloy and inject it into the evaporating dish. Place the evaporating dish on an iron stand, use an alcohol lamp to keep the gallium indium tin alloy in a molten state, and then use a glass rod to stir the mixture of sodium alginate powder and gallium indium tin alloy until the sodium alginate powder is completely wrapped by the gallium indium tin alloy. Transfer the obtained silver colloid to a beaker, add 50mL of distilled water, heat it in a water bath to 60°C, and then transfer it to an ultrasonic cell crusher. After ultrasonic treatment for 30 minutes, the electrode membrane biomass gel conductive ink is obtained.

[0040] Constructing a biomass gel artificial muscle blade mold to prepare the actuating membrane and pre-embed the heating wire

[0041] Draw a mold with the required fan blade shape inside in the 3D modeling software, with a wall height of 15mm, draw a scale at the position 10mm from the bottom of the inner wall, and draw a support with a height of 0.5mm inside according to the required pre-embedded resistance wire track. Use ABS material to print the drawn mold, then place the resistance wire on the support, pour the biomass gel bionic artificial muscle fan blade actuation membrane solution obtained in step 1 into it, add it to the scale, and then put the mold into a vacuum drying oven, vacuum dry at 60℃ for 48h, and you can get the biomass gel artificial muscle fan blade main body 1 part.

[0042] Printing biomass gel artificial muscle driving electrodes

[0043] Pour the biomass gel conductive ink obtained in the second step into the extrusion tank of the clay printer and insulate the tank. Design a fixed mold according to the biomass gel artificial muscle fan blade obtained in the third step to ensure that the top of the mold is flush with the surface of the film to obtain the best printing effect. Fix it on the printing plate of the clay printer, re-level its Z axis, then start the clay printer, print the biomass gel conductive ink in the pre-designed electrode shape, and obtain electrode film 2. After printing, transfer the fan blade together with the mold to a vacuum drying oven and dry it at 60°C for 6h. After drying, repeat four times to obtain an electrode of sufficient thickness to ensure that the electrode has sufficient conductivity and toughness. After the electrode on one side is printed, flip the biomass gel artificial muscle fan blade and repeat the above operation to make the electrode on the other side.

[0044] Repair and encapsulation of biomass gel artificial muscle blades

[0045] The biomass gel conductive ink in the clay printer is replaced with the bionic artificial muscle fan blade electro-actuated membrane solution 3, and the clay printer is also used to inject the actuated membrane solution into the gap between the electrode membranes 2, and finally dried until the surface is flush to ensure the integrity of the fan blade and extend its life. Finally, the obtained bionic artificial muscle fan blade is wrapped with a polyvinyl chloride film and placed in a vacuum packaging machine for packaging to obtain a bionic artificial muscle fan blade with both rigidity and flexibility and self-adjusting curvature.

[0046] In the above steps, the reagent materials used are: sodium alginate (analytical grade, 90%), glycerol (≥99%), ionic liquid 1-ethyl-3-methylimidazolium tetrafluoroborate ([EM Im][BF4], analytical grade, 99%), liquid metal (indium tin alloy, melting point 47°C), heating wire (Φ0.5mm). The other auxiliary experimental tools are: beaker (200mL), analytical balance, medicine spoon, qualitative filter paper (Φ15cm), magnetic stirrer, glass rod, pipette, ultrasonic cell crusher, mortar, 3D printer, clay printer, vacuum drying oven, vacuum packaging machine.

[0047] Example 2

[0048] Control method of free curvature bionic artificial muscle fan blades: each of the eight electrodes connected to the root of the fan blade electrode membrane is numbered 1-8, and No. 1 and No. 8, No. 2 and No. 7, No. 3 and No. 6 are paired in pairs, which are the electrode power-on areas, and the required voltage and direction must be applied according to the programming; No. 4 and No. 5 are the heating wire power-on areas, which can be connected to the positive and negative poles of the power supply.

[0049] When the fan blade is heated, before all deformation strategies are implemented, the fan blade is heated as a whole to soften the electrode film and the actuator film, and regions 4 and 5 are connected to the positive and negative poles of the power supply.

[0050] Control the curling of the outer fan blades: when the fan blades need to be concave downward, area 1 is connected to the positive pole of the power supply and area 8 is connected to the negative pole of the power supply; when the fan blades need to be convex upward, area 1 is connected to the negative pole of the power supply and area 8 is connected to the positive pole of the power supply.

[0051] Control the curling of the middle fan blades: When the middle part of the fan blades needs to be concave, connect area 2 to the positive pole of the power supply and area 7 to the negative pole of the power supply; when the fan blades need to be convex upward, connect area 1 to the negative pole of the power supply and area 8 to the positive pole of the power supply.

[0052] Control the curling of the inner fan blades: when the inner side of the fan blade is concave downward, area 3 is connected to the positive pole of the power supply and area 6 is connected to the power supply; when the inner side of the fan blade is convex upward, area 3 is connected to the negative pole of the power supply and area 6 is connected to the positive pole of the power supply.

[0053] Therefore, the present invention adopts a preparation process and control method of a free curvature bionic artificial muscle fan blade of the above structure, and adds an ionic liquid with a large molecular weight difference between anions and cations, so that the bionic artificial muscle achieves a higher output force density and service life. At the same time, compared with traditional viscoelastic bionic artificial muscle materials, the high melting point of [EM Im][BF4] gives the bionic artificial muscle a higher structural strength at room temperature. A high melting point gallium indium tin alloy is added to the bionic artificial muscle electrode membrane to replace carbon nanotubes. Compared with traditional electrode membranes, liquid metal has a higher conductivity and has the fluidity of liquid at high temperatures, which greatly reduces the need for the bionic artificial muscle to overcome its own viscoelastic force during output, so that it has a higher energy conversion efficiency, and its solidification property at room temperature works together with [EMIm][BF4] to enable the artificial muscle to have the ability to cool down and shape after reaching a specific shape, thereby avoiding the reduction in life caused by long-term work of the artificial muscle. Compared with traditional or metal or plastic fan blades, using bionic artificial muscle as a fan blade will make it have higher flexibility. Traditional fan blades have a fixed shape, and their energy efficiency curve and wind pressure-speed curve are fixed. They are only suitable for specific occasions, and a large amount of energy will be lost in situations where reverse thrust is required. The curvature of the bionic artificial muscle blades can be changed at will and can achieve the effect of flipping the blades. This design allows the propeller using bionic artificial muscles to adapt to different speed ranges while having the best energy efficiency curve, and can meet the requirements of efficient propulsion in both positive and negative directions. A partitioned electrode design is adopted, and the electrode is constructed by 3D printing additive manufacturing. The repeated casting process allows the interfaces of each part to be well attached, giving the artificial muscle blades good integrity, and the electrode shape can be freely customized according to needs. This allows the bionic artificial muscle blades to have more surface curvature options, which is helpful for the study of fluid dynamics, expands the options for energy-saving propellers, and provides new ideas for the future development of artificial muscles.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A preparation process of a free curvature bionic artificial muscle fan blade, characterized in that: The following steps are involved: S1: preparing a bionic artificial muscle fan blade electro-actuated membrane solution; weighing 4 g of sodium alginate, adding 200 mL of distilled water into a beaker, pouring in sodium alginate powder to completely dissolve it, adding 6 mL of propylene glycol and 4 mL of ionic liquid, and stirring until the solution presents a colorless gel-like substance without solid particles or flocs; then subjecting the solution to ultrasonic treatment for 10 minutes to remove bubbles, thereby obtaining a bionic artificial muscle fan blade electro-actuated membrane solution; S2: Prepare the electrode membrane biomass conductive ink; weigh the sodium alginate powder and put it into a watch glass, inject the high melting point gallium indium tin alloy into it, heat and melt the gallium indium tin alloy, use a glass rod to stir so that the sodium alginate powder is completely covered by the gallium indium tin alloy, and present a silver colloid state, then transfer it to a beaker, add 50 ml of distilled water and ultrasonically disperse it for 30 minutes, and stir at 60°C for 1 hour to obtain the biomass conductive ink used for artificial muscle fan blades; S3: preparing an actuated membrane fan blade with a self-heating function; using a 3D printer to print a designed fan blade-shaped mold with ABS as the material, setting up the heating wire according to the preset shape in the mold, and then pouring the bionic artificial muscle fan blade electro-actuated touch solution obtained in step S1 into the mold, and drying it at a constant temperature of 60° C. in a vacuum drying oven for 48 hours to obtain the main part of the artificial muscle fan blade; S4: Printing the driving electrodes of the artificial muscle blades; pouring the biomass conductive ink obtained in step S2 into the slurry tank of the clay printer, placing the main part of the biomass gel artificial muscle blade obtained in step S3 into a customized positioning mold so that its upper plane is flush with the top surface of the mold; placing the mold on the base of the clay printer, printing the shape of the upper surface electrode on the artificial muscle blade actuation membrane according to the pre-programmed shape, and filling the contact surface for connecting the circuit at the tail of the artificial muscle, placing it in a drying oven for drying, and repeating 5 times to obtain the top electrode membrane; then inverting the blade and repeating the above steps to make the bottom electrode membrane; S5: Replace the biomass conductive ink with the electro-actuated membrane solution of the bionic artificial muscle fan blade, and use a clay printer to fill the gap between the electrode membrane with the electro-actuated membrane solution to ensure the integrity of the fan blade; finally, wrap the obtained bionic artificial muscle fan blade with polyvinyl chloride film, and put it into a vacuum packaging machine for packaging to obtain a bionic artificial muscle fan blade with both rigidity and flexibility and self-adjusting curvature.

2. The process for preparing a free curvature bionic artificial muscle blade according to claim 1, characterized in that: The dissolution conditions of sodium alginate added to distilled water in step S1 are heating in a water bath at 60° C. and stirring at a constant speed of 800 r / min.

3. The preparation process of a free curvature bionic artificial muscle blade according to claim 2, characterized in that: In step S2, 2 g of sodium alginate powder is taken, 2 mL of liquid gallium indium tin alloy is taken and mixed with the sodium alginate powder, and the mixture is heated in a water bath to maintain the temperature at 55° C. so that the sodium alginate powder is completely coated with the gallium indium tin alloy.

4. A control method for a free curvature bionic artificial muscle fan blade, characterized in that: The free curvature bionic artificial muscle fan blade prepared by the preparation process of a free curvature bionic artificial muscle fan blade as described in any one of claims 1 to 3 is controlled by the following method: each of the eight electrodes connected to the root of the fan blade electrode membrane is numbered 1-8, with No. 1 and No. 8, No. 2 and No. 7, and No. 3 and No. 6 being pairs of two, which are the electrode power-on areas, and the required voltage and direction need to be applied as programmed; No. 4 and No. 5 are the heating wire power-on areas, which can be connected to the positive and negative poles of the power supply.

5. The control method of a free curvature bionic artificial muscle blade according to claim 4, characterized in that: When the fan blade is heated, before all deformation strategies are implemented, the fan blade is heated as a whole to soften the electrode film and the actuator film, and regions 4 and 5 are connected to the positive and negative poles of the power supply.

6. The control method of a free curvature bionic artificial muscle blade according to claim 5, characterized in that: Control the curling of the outer fan blades: when the fan blades need to be concave downward, area 1 is connected to the positive pole of the power supply and area 8 is connected to the negative pole of the power supply; when the fan blades need to be convex upward, area 1 is connected to the negative pole of the power supply and area 8 is connected to the positive pole of the power supply.

7. The control method of a free curvature bionic artificial muscle blade according to claim 6, characterized in that: Control the curling of the middle fan blades: When the middle part of the fan blades needs to be concave, connect area 2 to the positive pole of the power supply and area 7 to the negative pole of the power supply; when the fan blades need to be convex upward, connect area 1 to the negative pole of the power supply and area 8 to the positive pole of the power supply.

8. The control method of a free curvature bionic artificial muscle blade according to claim 7, characterized in that: Control the curling of the inner fan blades: when the inner side of the fan blade is concave downward, area 3 is connected to the positive pole of the power supply and area 6 is connected to the power supply; when the inner side of the fan blade is convex upward, area 3 is connected to the negative pole of the power supply and area 6 is connected to the positive pole of the power supply.

Images