A dielectric elastomer-based wireless vibration-crawling robot and method

Abstract

The application discloses a wireless vibration crawling robot and method based on dielectric elastomer. The robot comprises a spring support integrated with a wireless circuit board, spring steel feet installed on both sides and a crawling surface to form different angles, and a multilayer stack of silicone rubber dielectric elastomer drivers wrapped around the outer periphery of the spring support and containing multilayer dielectric elastomer films, wherein the multilayer dielectric elastomer films are prepared by a single-layer film through a kind of dry stacking method based on heat curing; periodic high-voltage electricity is applied to the drivers to make the drivers form periodic expansion and contraction, thereby driving the expansion and contraction movement of the spring support and the spring steel feet, the spring steel feet are subjected to different frictional forces due to the different angles with the ground, and the spring steel feet move forward in the preset direction to realize movement. The application can be free from the interference of traditional wire winding during movement, can work independently, and can realize the lightweight of the device, and can work in a low-voltage range (lower than 350 V).

Description

Technical Field

[0001] This invention relates to the field of soft robot technology, and more particularly to a wireless vibration crawling robot and method based on a dielectric elastomer. Background Technology

[0002] Dielectric elastomer actuators consist of a dielectric elastomer film and flexible electrodes coated on its upper and lower surfaces. Under the influence of an electric field, positive and negative charges accumulate on the upper and lower surfaces of the film, forming Maxwell stress, which triggers reversible deformation of the elastomer film to convert electrical energy into mechanical energy. High energy density, fast response speed, large deformation, and light weight are its outstanding advantages. It has enormous application potential in fields such as biomimetic robot design and wearable sensing and monitoring system development. Especially in the field of soft robot design and fabrication, dielectric elastomers are an important material foundation for achieving lightweight, wearable, and intelligent actuators in the future. To broaden the application scope of dielectric elastomer actuators, improve the matching degree between the actuation form and actual life motion patterns, and enhance the actuation stability in complex environments, the design and fabrication of soft robots with wireless self-powered capabilities is of great significance.

[0003] However, the application of thousands to tens of thousands of volts to dielectric elastomers poses a significant challenge to insulating encapsulation technology. Furthermore, to overcome the limitations of motion range imposed by wiring harnesses, dielectric elastomer robots must integrate self-driving systems. However, the high output voltage requires electronic components with high voltage withstand capabilities. These components are generally expensive and bulky, resulting in costly, large, and heavy integrated circuit boards. These factors limit the application and development of integrated dielectric elastomer robots.

[0004] To broaden the application scope of dielectric elastomer robots and improve their integration and stability, designing highly integrated dielectric elastomer robots that can be driven at low voltages is of great significance. Current research lacks effective strategies to simultaneously address the problem of excessively high driving voltages in vibration-type crawling robots and achieve wireless operation. Summary of the Invention

[0005] To address the problems in the background art, this invention proposes a wireless vibration crawling robot and method based on dielectric elastomers, which solves the problems of excessively high driving voltage in traditional crawling robots based on dielectric elastomers, and the inability of high-voltage power supplies to be portable and integrated with dielectric elastomer actuators.

[0006] The technical solution of this invention is: I. A method for preparing a multilayer dielectric elastomer film The preparation method includes: 1) Prepare a silicone rubber prepolymer liquid, apply the silicone rubber prepolymer liquid to a glass substrate and a PET substrate respectively, and heat and cure both to obtain a glass substrate silicone dielectric elastomer film and a PET substrate silicone dielectric elastomer film respectively; Step 1) specifically refers to: A silicone rubber prepolymer was prepared by mixing Ecoflex 0030 silicone and Sylgard 184 silicone at a mass ratio of 1:1. The silicone rubber prepolymer was then applied to glass substrates and PET substrates using an automatic film coating agent and cured at 85°C for 1 hour. The resulting silicone-based dielectric elastomer film on both the glass substrate and the PET substrate had a thickness of approximately 10 micrometers and an area of ​​120 square centimeters (10 cm * 15 cm). The mass ratio of base silicone and crosslinking agent in Sylgard 184 silicone rubber prepolymer is 20:1. 2) Carbon nanotube electrode solution and a small amount of binding layer liquid are sequentially sprayed onto the surface of a glass-based silicon-based dielectric elastomer film to obtain a glass-based silicon-based dielectric elastomer film with electrodes. In practice, the standard for spraying the electrode solution is to achieve a film surface resistance of approximately 100 kΩ, and the standard for spraying the binding layer solution is 1 / 15 mL / cm. 2 .

[0007] In step 2), the electrode solution is a carbon nanotube dispersion, which is formed by uniformly dispersing carboxylated single-walled carbon nanotube powder using a mixture of isopropanol and water; the mass ratio of isopropanol:water:single-walled carbon nanotube powder is 1120:160:1. Specifically, the electrode solution is a carbon nanotube dispersion. 0.025 g of single-walled carbon nanotube powder is dispersed in a mixture of isopropanol and water to form a dispersion. The volume ratio of isopropanol to water in the isopropanol and water mixture is 36:4v / v%. After centrifuging the dispersion, the supernatant is collected at a speed of 8000 rpm / min for 10 min. The supernatant is then sprayed onto the surface of a glass-based silicon-based dielectric elastomer film.

[0008] In step 2), the binding layer liquid is obtained by diluting Sylgard 184 type silica gel with a base gel and crosslinking agent mass ratio of 10:1 in n-hexane at a dilution ratio of 10 wt% and stirring thoroughly with a stirring rod.

[0009] 3) Align the surface of the PET-based silicon-based dielectric elastomer film with the surface of the glass-based silicon-based dielectric elastomer film with electrodes obtained in step 2) and then perform defoaming treatment for 5 seconds in a vacuum laminator. Then, heat and cure the bonding layer in an oven at 105°C for 15 minutes. Then, peel off the PET substrate of the PET-based silicon-based dielectric elastomer film, so that the film originally on the PET substrate is transferred to the glass substrate, thereby completing one lamination. 4) Repeat step 3) until the desired number of layers is stacked, specifically 12 layers, to obtain a multilayer dielectric elastomer film.

[0010] II. A multilayer dielectric elastomer film It is prepared using the method described above.

[0011] III. A Wireless Vibration Crawling Robot Includes a wireless circuit board, spring steel feet, spring supports, and a multilayer stacked silicone rubber dielectric elastomer actuator containing multiple layers of dielectric elastomer films; The multilayer stacked silicone rubber dielectric elastomer actuator is fixedly wrapped around the outer periphery of the spring bracket. The wireless circuit board is integrated inside the spring bracket. The wireless circuit board is electrically connected to both ends of the multilayer stacked silicone rubber dielectric elastomer actuator on the outer periphery of the spring bracket. A spring steel foot for contacting the crawling surface is installed at each end of the spring bracket. According to the forward direction, the two spring steel feet are divided into a front foot and a rear foot. The acute angle formed between the rear foot and the crawling surface is greater than the acute angle formed between the front foot and the crawling surface.

[0012] The spring support includes spring end caps symmetrically arranged at both ends of the spring body; The spring end caps at both ends of the spring body are fixedly connected by an insulating gasket and a corresponding spring steel foot. The multilayer stacked silicone rubber dielectric elastomer driver is fixedly wrapped around the outer periphery of the spring body. The wireless circuit board integrated inside the spring body is fixedly connected to the spring end cap on one side. The multilayer stacked silicone rubber dielectric elastomer actuator is wrapped around the outer periphery of the spring body by a multilayer dielectric elastomer film and fixed by heating and curing.

[0013] The wireless circuit board includes an integrated boost circuit board and a battery; The integrated boost circuit board includes an input interface module, a contactless switch module, an MCU control module, a power amplifier module, and an output module; The input interface module is electrically connected to the battery; the contactless switch module is electrically connected to the input interface module to control the current flow; the MCU control module is electrically connected to the contactless switch module, the power amplifier module, and the output module respectively; the power amplifier module is electrically connected to the contactless switch module to amplify the voltage conducted from the battery; the output module is electrically connected to the power amplifier module and is externally connected to a multilayer stacked silicone rubber dielectric elastomer driver to provide voltage to the multilayer stacked silicone rubber dielectric elastomer driver.

[0014] When a voltage is applied to the multilayer stacked silicone rubber dielectric elastomer actuator, the actuator, in its initial state, undergoes radial expansion, which in turn causes the spring body to expand radially. The increased radial dimension of the spring body further expands the overall size of the spring body, pushing the spring end caps on both sides to extend the corresponding spring steel feet. After the voltage is removed, the multilayer stacked silicone rubber dielectric elastomer actuator returns to its initial state, causing the spring body to return to its original state. The decreased radial dimension of the spring body further shrinks the overall size of the spring body, pushing the spring end caps on both sides to retract the spring steel feet. The extension and retraction of the corresponding spring steel feet is achieved by repeatedly applying periodic voltages.

[0015] IV. A Driving Method for a Wireless Vibration Crawling Robot The driving method includes: S1: A voltage is applied to the multilayer stacked silicone rubber dielectric elastomer driver in its initial state via a wireless circuit board, causing deformation and driving the front foot to move in the forward direction and the hind foot to move in the backward direction. The distance the hind foot moves in the backward direction is less than the distance the front foot moves in the forward direction. Step S1 specifically involves: The wireless vibration crawling robot in its initial state is placed on a crawling surface, with its front and hind feet in contact with the surface. A voltage is then applied to the multilayer stacked silicone rubber dielectric elastomer actuator via a wireless circuit board. The actuator, in its initial state, expands radially, which in turn causes the spring body to expand radially. The increased radial dimension of the spring body leads to an overall expansion of the spring body, which in turn pushes the spring end caps on both sides to extend the corresponding spring steel feet. The acute angle formed between the hind foot and the crawling surface is greater than that between the front foot and the surface, resulting in a greater forward friction force on the hind foot than a backward friction force on the front foot. Consequently, the forward displacement of the front foot is greater than the backward displacement of the hind foot, causing the entire wireless vibration crawling robot to move forward. S2: Remove the voltage applied in step S1 via the wireless circuit board, so that the multilayer stacked silicone rubber dielectric elastomer actuator returns to its initial state, causing the hind foot to move in the forward direction and the front foot to move in the backward direction, and the distance the front foot moves in the backward direction is less than the distance the hind foot moves in the forward direction. Step S2 specifically involves: When the voltage applied in step S1 is removed via the wireless circuit board, the multilayer stacked silicone rubber dielectric elastomer actuator returns to its initial state, thereby causing the spring body to return to its original state. The radial dimension of the spring body shrinks, which in turn causes the overall spring body to shrink, thereby pushing the spring end caps on both sides to retract the spring steel feet. The direction of the friction force on the crawling surface of the front and rear feet is opposite to that in step S1, and the acute angle formed between the rear foot and the crawling surface is greater than the acute angle formed between the front foot and the crawling surface, so that the backward friction force on the rear foot is less than the forward friction force on the front foot, and thus the backward displacement distance of the front foot is less than the forward displacement distance of the rear foot, and the wireless vibration crawling robot moves forward as a whole.

[0016] S3: Repeat steps S1 and S2, and the wireless vibration crawling robot moves in one direction.

[0017] The beneficial effects of this invention are: This invention reduces the driving voltage by stacking large-area ultrathin films of silicone rubber dielectric elastomer, making it possible to integrate the dielectric elastomer actuator with the boost circuit board. In the structural design, by combining components such as springs, spring steel feet, end caps, and circuit boards, the strain of the dielectric elastomer actuator causes the spring-circuit board assembly to resonate, effectively converting the film displacement into the displacement of the crawling robot, achieving a faster crawling speed. The technical means provided by this invention has the following advantages: 1) The dry stacking method can screen the film thickness and defects before stacking, control the film uniformity, improve the robot's yield, and make large-area actuator fabrication feasible; 2) The robot's size is only a few centimeters, realizing wireless miniaturization of the device, which is beneficial for application in more scenarios, such as crawling scenarios in pipes and planes. It can avoid interference from traditional wire entanglement during movement and achieve device lightweighting, operating within a low voltage range (below 350 V). Attached Figure Description

[0018] The accompanying drawings are used to provide an understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0019] Figure 1 This is a schematic diagram illustrating the fabrication of a large-area ultrathin film stack for the wireless vibration crawling robot described in this application. Figure 2 This is a schematic diagram of the foot of the wireless vibration crawling robot described in this application; Figure 3 This is a graph showing the effect of the aspect ratio on the movement speed of the wireless vibration crawling robot described in this application. Figure 4 This is an explosion diagram of the wireless vibration crawling robot described in this application; Figure 5 This is a voltage-velocity data graph of the wireless vibration crawling robot described in this application; Figure 6 This is a schematic diagram of the wireless vibration crawling robot described in this application crawling inside a pipe. Figure 7 This is a schematic diagram of the planar crawling of the wireless vibration crawling robot described in this application; Figure 8 This is a force analysis diagram of the wireless vibration crawling robot described in this application.

[0020] 1. Multilayer stacked silicone rubber dielectric elastomer actuator; 2. Spring; 3. Spring steel foot; 4. Insulating gasket; 5. Spring end cap; 6. Integrated boost circuit board; 7. Battery. Detailed Implementation

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] To make the purpose, technical solution and advantages of this application clearer, the embodiments of this application will be described in detail below.

[0023] The present invention will be further described in detail below with reference to specific examples, but these examples should not be construed as limiting the present invention.

[0024] like Figure 1 As shown, a method for preparing a multilayer dielectric elastomer film includes: 1) Prepare a silicone rubber prepolymer solution, apply the silicone rubber prepolymer solution to a glass substrate and a PET substrate respectively, and heat and cure both to obtain a glass substrate silicone dielectric elastomer film and a PET substrate silicone dielectric elastomer film respectively. Step 1) specifically involves: A silicone rubber prepolymer was prepared by mixing Ecoflex 0030 silicone and Sylgard 184 silicone at a mass ratio of 1:1. The silicone rubber prepolymer was then applied to glass substrates and PET substrates using an automatic film coating agent and cured at 85°C for 1 hour. The resulting silicone-based dielectric elastomer film on both the glass substrate and the PET substrate had a thickness of approximately 10 micrometers and an area of ​​120 square centimeters (10 cm * 15 cm). The mass ratio of base silicone and crosslinking agent in Sylgard 184 silicone rubber prepolymer is 20:1. 2) Carbon nanotube electrode solution and a small amount of binding layer liquid are sequentially sprayed onto the surface of a glass-based silicon dielectric elastomer film to obtain a glass-based silicon dielectric elastomer film with electrodes. In practice, the standard for spraying the electrode solution is to achieve a film surface resistance of approximately 100 kΩ, and the standard for spraying the binding layer solution is 1 / 15 mL / cm. 2 .

[0025] In step 2), the electrode solution is a carbon nanotube dispersion, which is formed by uniformly dispersing carboxylated single-walled carbon nanotube powder using a mixture of isopropanol and water; the mass ratio of isopropanol:water:single-walled carbon nanotube powder is 1120:160:1. Specifically, the electrode solution is a carbon nanotube dispersion. 0.025 g of single-walled carbon nanotube powder is dispersed in a mixture of isopropanol and water to form a dispersion. The volume ratio of isopropanol to water in the isopropanol and water mixture is 36:4v / v%. After centrifuging the dispersion, the supernatant is collected at a speed of 8000 rpm / min for 10 min. The supernatant is then sprayed onto the surface of a glass-based silicon dielectric elastomer film.

[0026] In step 2), Sylgard 184 silica gel with a base gel and crosslinking agent mass ratio of 10:1 was diluted in n-hexane at a dilution ratio of 10 wt% and stirred thoroughly with a stir bar to obtain the binding layer liquid.

[0027] 3) Align the surface of the PET-based silicon-based dielectric elastomer film with the surface of the glass-based silicon-based dielectric elastomer film with electrodes obtained in step 2) and then perform defoaming treatment for 5 seconds in a vacuum laminator at a pressure of 100 kPa. Then, heat and cure the bonding layer in an oven at 105 °C for 15 minutes. Finally, peel off the PET substrate of the PET-based silicon-based dielectric elastomer film so that the film originally on the PET substrate is transferred to the glass substrate, thereby completing one lamination. 4) Repeat step 3) until the desired number of layers is stacked, specifically 12 layers, to obtain a multilayer dielectric elastomer film.

[0028] Furthermore, film thickness and defect conditions can be screened before each stack.

[0029] A multilayer dielectric elastomer film is prepared using a method for preparing multilayer dielectric elastomer films.

[0030] like Figure 2 and Figure 4As shown, a wireless vibration crawling robot employing a multilayer dielectric elastomer film includes a wireless circuit board, spring steel feet 3, spring supports, and a multilayer stacked silicone rubber dielectric elastomer actuator 1 containing a multilayer dielectric elastomer film. A multi-layered stacked silicone rubber dielectric elastomer actuator 1 is fixedly wrapped around the outer periphery of the spring bracket. A wireless circuit board is integrated inside the spring bracket, and the wireless circuit board is electrically connected to both ends of the multi-layered stacked silicone rubber dielectric elastomer actuator 1 on the outer periphery of the spring bracket. A spring steel foot 3 is installed at each end of the spring bracket for contact with the crawling surface. Based on the direction of travel, the two spring steel feet 3 are divided into a front foot and a rear foot. The acute angle formed between the rear foot and the crawling surface is greater than the acute angle formed between the front foot and the crawling surface. The crawling surface is the ground or a pipe.

[0031] Furthermore, the angles formed by the forelegs and the crawling surface, and the angles formed by the hind legs and the crawling surface, can be adjusted by adjusting the angles formed with the crawling surface.

[0032] Specifically, the spring steel foot 3 is bent into angles of 20° and 10° with the crawling surface using a clamping mold. The 20° foot is installed as the rear foot, and the 10° foot is installed as the front foot.

[0033] The spring support includes spring end caps 5 symmetrically arranged at both ends of the spring body 2; The spring end caps 5 at both ends of the spring body 2 are fixedly connected by an insulating pad 4 and a corresponding spring steel foot 3. The outer periphery of the spring body 2 is fixedly wrapped with a multi-layer stacked silicone rubber dielectric elastomer driver 1. The wireless circuit board integrated inside the spring body 2 is fixedly connected to the spring end cap 5 on one side. The spring end cap 5 extends inward with a horizontal plate to support the wireless circuit board. The spring body 2 has a wire diameter of 0.5 mm, and the spring steel foot 3 is made of spring steel, weighing approximately 0.5 g. The spring end cap 5 is 3D printed using lightweight resin material, with an overall weight of approximately 1 g. This reduces the load on the actuator and is used to seal the ports on both sides of the 3D printed part.

[0034] The multilayer stacked silicone rubber dielectric elastomer actuator 1 is wrapped around the outer periphery of the spring body 2 using a multilayer dielectric elastomer film winding process and then fixed by heat curing. Specifically, a bonding layer liquid is sprayed onto the multilayer dielectric elastomer film at a standard spraying ratio of 1 / 15 mL / cm. 2 After the solvent in the bonding layer has evaporated, the multilayer dielectric elastomer film is wrapped around the spring support using a winding process and then placed in an oven at 55 degrees Celsius for 2 hours to cure the bonding layer.

[0035] like Figure 3 As shown, we know from the formula for the natural frequency and resonant frequency of a spring that, at the elastic coefficient k sWith the spring thickness remaining constant, as the spring length l increases, the resonant frequency f... s The speed will decrease. Therefore, it is necessary to explore whether the spring length has the same effect on the driving performance of the vibration robot.

[0036] ; in, For the spring density, Let l be the cross-sectional area of ​​the spring and l be the length of the spring.

[0037] Three tubular actuators with different aspect ratios were prepared in the experiment, namely 1cm:0.8cm (…). Figure 3 A) 3cm:0.8cm ( Figure 3 B), 6cm:0.8cm ( Figure 3 C). After mounting the vibrating robot, driving tests were conducted under different voltages and frequencies. Experimental results show that the vibrating robot with an aspect ratio of 1:0.8 exhibits a peak velocity (near its resonant frequency) of approximately 8 cm / s at 550 Hz. The vibrating robot with an aspect ratio of 3:0.8 exhibits a peak velocity (near its resonant frequency) of approximately 12 cm / s at 350 Hz. The vibrating robot with an aspect ratio of 6:0.8 exhibits a peak velocity of approximately 18 cm / s at 200 Hz. The resonant frequency of the robot with an aspect ratio of 6:0.8 is lower than that of the robot with an aspect ratio of 3:0.8, and the resonant frequency of the robot with an aspect ratio of 3:0.8 is lower than that of the robot with an aspect ratio of 1:0.8. This matches the prediction made by the formula for calculating the resonant frequency of a spring.

[0038] The wireless circuit board includes an integrated boost circuit board 6 and a battery 7; The integrated boost circuit board 6 is electrically connected to the battery 7, which is placed below and in close contact with the integrated boost circuit board 6.

[0039] The integrated boost circuit board 6 includes an input interface module, a contactless switch module, a program programming module, an output feedback module, an MCU control module, a power amplifier module, and an output module; The input interface module is electrically connected to battery 7, providing power to other modules; the contactless switch module is electrically connected to the input interface module, used to control the current flow, i.e., for manual system on / off operation; the control program programming module is electrically connected to the MCU control module, and is used for program programming via an external host computer. The programmed program is stored inside the MCU control module, and can be disconnected from the host computer after programming. The program drives the boost circuit board, which outputs high-voltage pulse waves to the dielectric elastomer; the MCU control module is connected to the output feedback module, the contactless switch module, and the power amplifier module. The large module and the output module are electrically connected. The large module controls the start-up and shutdown and the output voltage by outputting a PWM signal to the power amplifier module. The output voltage frequency is controlled by outputting a PWM signal to the output module. The output feedback module also processes the readback signal. The power amplifier module and the contactless switch module are electrically connected. The power amplifier module is used to amplify the voltage conducted from the battery 7. Specifically, its function is to boost the lithium battery voltage to the working voltage. The output module and the power amplifier module are electrically connected and externally connected to the multilayer stacked silicone rubber dielectric elastomer driver 1, which provides high voltage to the multilayer stacked silicone rubber dielectric elastomer driver 1.

[0040] The input interface module includes a power supply regulator circuit and positive and negative power terminals. The contactless switch module consists of a Hall sensor and a metal-oxide-semiconductor field-effect transistor. When the contactless switch module senses an approaching magnetic field, the switch opens, allowing the battery to power the circuit board. After the MCU control module starts, it locks the switch state to prevent the switch from closing when the magnetic field moves away. To ensure that the robot can effectively drive the load, a commercially available lithium battery with a capacity of 20 mAh and a weight of 0.9 g was selected, and the designed integrated boost circuit board weighs 2.1 g.

[0041] The integrated boost circuit board 6 can boost the DC voltage output from commercial lithium batteries to a pulse wave voltage of 0-500 V. The boost circuit board uses a flyback boost principle, a single-stage boost, which can boost the 3.3 V-4.2 V lithium battery voltage to 500 V. The frequency and magnitude of the output voltage can be adjusted through the built-in chip.

[0042] A high-voltage alternating current is applied to the electrodes inside the multilayer stacked silicone rubber dielectric elastomer actuator 1. The multilayer stacked silicone rubber dielectric elastomer actuator 1 in its initial state expands radially outward, which in turn drives the spring body 2 to expand radially outward. The radial dimension of the spring body 2 increases, which in turn drives the overall expansion of the spring body 2, which in turn pushes the spring end caps 5 on both sides to extend the corresponding spring steel feet 3. After the high-voltage alternating current is removed, the multilayer stacked silicone rubber dielectric elastomer actuator 1 returns to its initial state, which in turn drives the spring body 2 to return to its original state. The radial dimension of the spring body 2 decreases, which in turn drives the overall shrinkage of the spring body 2, which in turn pushes the spring end caps 5 on both sides to retract the spring steel feet 3. The extension and retraction movement of the corresponding spring steel feet 3 is achieved by repeatedly applying periodic high-voltage alternating current.

[0043] Specifically, a dielectric elastomer is an electroactive polymer. When a high-voltage alternating current is applied to the flexible electrodes on the inner and outer surfaces of the thin film, electrostatic compression occurs on the upper and lower surfaces of the film, generating Maxwell stress, which compresses the film in the thickness direction. Since the material is approximately incompressible, the reduction in thickness inevitably leads to expansion in the planar direction. Silicon-based dielectric elastomers have high response frequencies, reaching hundreds of Hz, and therefore can rapidly reciprocate under alternating current of hundreds of Hz. After the thin film is wound around the surface of a spring, its deformation mode changes from "planar expansion" to radial expansion: when voltage is applied, the film expands radially, driving the spring to expand outward; when the voltage is removed, the film returns to its original shape, and the spring rebounds. Under alternating current of hundreds of Hz, the spring is subjected to high-frequency radial expansion and contraction forces, generating continuous mechanical vibration.

[0044] A driving method for a wireless vibration crawling robot includes: S1: A high-voltage alternating current is applied to the multilayer stacked silicone rubber dielectric elastomer driver 1 in its initial state via a wireless circuit board, which causes deformation, driving the front foot to move in the forward direction and the hind foot to move in the backward direction. The distance the hind foot moves in the backward direction is less than the distance the front foot moves in the forward direction. Step S1 is as follows: The wireless vibration crawling robot in its initial state is placed on the crawling surface, with its front and hind feet in contact with the surface. A high-voltage AC current is then applied to the multilayer stacked silicone rubber dielectric elastomer actuator 1 via a wireless circuit board. The multilayer stacked silicone rubber dielectric elastomer actuator 1 in its initial state expands radially outward, which in turn drives the spring body 2 to expand radially outward. The radial dimension of the spring body 2 increases, which in turn drives the overall expansion of the spring body 2. This pushes the spring end caps 5 on both sides, causing the corresponding spring steel feet 3 to extend. The acute angle formed between the hind foot and the crawling surface is greater than the acute angle formed between the front foot and the crawling surface, so that the forward friction force on the hind foot from the crawling surface is greater than the backward friction force on the front foot. As a result, the displacement distance of the front foot moving forward is greater than the displacement distance of the hind foot moving backward, and the wireless vibration crawling robot moves forward as a whole. S2: Remove the high voltage AC power applied in step S1 through the wireless circuit board, so that the multilayer stacked silicone rubber dielectric elastomer driver 1 returns to its initial state, driving the hind foot to move in the forward direction and the front foot to move in the backward direction, and the distance the front foot moves in the backward direction is less than the distance the hind foot moves in the forward direction. Step S2 is as follows: The high-voltage AC power applied in step S1 is removed by the wireless circuit board, and the multilayer stacked silicone rubber dielectric elastomer driver 1 returns to its initial state, thereby driving the spring body 2 to return to its original state. The radial dimension of the spring body 2 decreases, thereby driving the overall shrinkage of the spring body 2, which in turn pushes the spring end caps 5 on both sides to retract the spring steel feet 3. The direction of the friction force on the crawling surface of the front and rear feet is opposite to that in step S1, and the acute angle formed between the rear foot and the crawling surface is greater than the acute angle formed between the front foot and the crawling surface, so that the backward friction force on the rear foot on the crawling surface is less than the forward friction force on the front foot on the crawling surface, thus making the backward displacement distance of the front foot less than the forward displacement distance of the rear foot, and the wireless vibration crawling robot moves forward as a whole. S3: Repeat steps S1 and S2 to enable the wireless vibration crawling robot to move in one direction.

[0045] like Figure 5 As shown, the speed of the wireless vibration crawling robot can be adjusted by the magnitude of the applied voltage.

[0046] like Figure 6 and Figure 7 As shown, the wireless vibration crawling robot can move in pipes / on the ground.

[0047] Specifically, the spring steel friction foot, which is inclined at a certain angle to the crawling surface, is a typical anisotropic friction structure. Its equivalent friction coefficient is determined by both the material's basic friction coefficient and the mechanical interlocking effect caused by the inclination angle. When sliding in the direction of the toe, the spring steel sheet is compressed and collapses, weakening the interlocking effect, and the equivalent friction coefficient is lower than the basic friction coefficient. When sliding against the direction of the toe, the steel sheet weds into the contact surface and generates additional resistance, and the equivalent friction coefficient is higher than the basic friction coefficient. The larger the inclination angle of the friction foot, the more significant the difference between the forward and reverse friction coefficients, and the more obvious the distinction between anchoring and sliding effects. This allows the reciprocating extension and retraction motion of the actuator to be converted into the robot's unidirectional crawling motion.

[0048] like Figure 8 As shown, a single drive cycle of the robot consists of two phases: extension and retraction of the tubular actuator. When the actuator extends, it pushes outwards, causing the overall body to lengthen. This results in a difference in the force and friction state between the hind and forelegs: the hind leg, with a 20° tilt angle, experiences a backward pushing force and slides against the direction of the toe. The larger tilt angle significantly increases the ground gripping force, resulting in increased friction F. f2 The hind foot significantly increases and forms a locking effect, making it difficult for the hind foot to slide backward; the forefoot, with a 10° tilt angle, is pushed forward and slides along the direction of the toe, with friction force F f1 Less than F f2 It can slide forward smoothly.

[0049] The vertical load on both the front and rear spring steel feet is G, the static friction coefficient between the spring steel feet and the ground is μ0, the direction to the right is the forward direction, and k is the engagement coefficient between the spring steel feet and the ground. Foreleg (10°, force applied in the direction of forward movement): F f1 =(μ0-ksin10°)ΧG; Low friction causes it to slide forward; Hind foot (20°, force applied in the opposite direction of forward movement): F f2 =(μ0+ksin20°)ΧG; High friction helps to inhibit backward movement; Elongation stage F f2 >F f1 Slide forward.

[0050] When the actuator retracts, it pulls inward, and the direction of force on the fore and hind feet reverses: the forefoot experiences a backward pulling force and slides against the direction of the toes, with frictional force F... f3 Increased, backward slippage is effectively suppressed; the hind foot is pulled forward and slides in the direction of the toes, friction force F f4 It is relatively small and can slide forward smoothly.

[0051] Forefoot (10°, reverse force): F f3=(μ0+ksin10°)ΧG; High friction helps to inhibit backward movement; Hind foot (20°, forward force): F f4 =(μ0-ksin20°)ΧG; Low friction causes it to slide forward; contraction phase F f3 >F f4 Slide forward.

[0052] In summary, the robot continues to crawl forward throughout the complete drive cycle.

[0053] Furthermore, the multilayer stacked silicone rubber dielectric elastomer actuator 1 is divided into left and right parts along the axial direction. By changing the different voltages applied to the left and right parts, the forces on the left and right sides of the robot are changed, thereby enabling turning in the left and right directions.

Claims

1. A method for preparing a multilayer dielectric elastomer film, characterized in that, The preparation method includes: 1) Prepare a prepolymer solution, apply the prepolymer solution to a glass substrate and a PET substrate respectively, and heat and cure both to obtain a glass substrate silicon-based dielectric elastomer film and a PET substrate silicon-based dielectric elastomer film respectively; 2) Electrode solution and bonding layer liquid are sequentially sprayed onto the surface of a glass-based silicon-based dielectric elastomer film to obtain a glass-based silicon-based dielectric elastomer film with electrodes. 3) Align the surface of the PET-based silicon-based dielectric elastomer film with the surface of the glass-based silicon-based dielectric elastomer film with electrodes obtained in step 2), perform vacuum lamination, then heat curing, and then peel off the PET substrate of the PET-based silicon-based dielectric elastomer film to complete one lamination. 4) Repeat step 3) until the desired number of layers are stacked to obtain a multilayer dielectric elastomer film.

2. The method for preparing a multilayer dielectric elastomer film according to claim 1, characterized in that, Step 1) specifically refers to: A prepolymer solution was prepared by mixing Ecoflex 0030 silicone and Sylgard 184 silicone at a mass ratio of 1:

1. The prepolymer solution was then applied to glass and PET substrates using an automatic film coating agent and cured at 85°C for 1 hour. The mass ratio of base adhesive to crosslinking agent in the Sylgard 184 silicone solution was 20:

1.

3. The method for preparing a multilayer dielectric elastomer film according to claim 1, characterized in that: In step 2), the electrode solution is a carbon nanotube dispersion, which is formed by dispersing carboxylated single-arm carbon nanotube powder with a mixture of isopropanol and water. The mass ratio of isopropanol:water:single-walled carbon nanotube powder is 1120:160:1; in step 2), the binding layer liquid is Sylgard 184 type silica gel with a mass ratio of base gel and crosslinking agent of 10:1, diluted in n-hexane at a dilution ratio of 10 wt%.

4. A multilayer dielectric elastomer film, characterized in that: It is prepared by any one of the methods described in claims 1-3.

5. A wireless vibration crawling robot employing the multilayer dielectric elastomer film as described in claim 4, characterized in that: The device includes a wireless circuit board, a spring steel foot (3), a spring support, and a multilayer stacked silicone rubber dielectric elastomer actuator (1) containing a multilayer dielectric elastomer film. The multilayer stacked silicone rubber dielectric elastomer driver (1) is fixedly wrapped around the outer periphery of the spring bracket. The wireless circuit board is integrated inside the spring bracket. The wireless circuit board is electrically connected to both ends of the multilayer stacked silicone rubber dielectric elastomer driver (1) on the outer periphery of the spring bracket. A spring steel foot (3) for contacting the crawling surface is installed at each end of the spring bracket. According to the forward direction, the two spring steel feet (3) are divided into a front foot and a rear foot. The acute angle formed between the rear foot and the crawling surface is greater than the acute angle formed between the front foot and the crawling surface.

6. A wireless vibration crawling robot according to claim 5, characterized in that: The spring support includes spring end caps (5) symmetrically arranged at both ends of the spring body (2); The spring end caps (5) at both ends of the spring body (2) are fixedly connected by an insulating pad (4) and a corresponding spring steel foot (3). The multilayer stacked silicone rubber dielectric elastomer driver (1) is fixedly wrapped around the outer periphery of the spring body (2). The wireless circuit board integrated inside the spring body (2) is fixedly connected to the spring end cap (5) on one side. The multilayer stacked silicone rubber dielectric elastomer actuator (1) is wrapped around the outer periphery of the spring body (2) by a multilayer dielectric elastomer film and fixed by heating and curing.

7. A wireless vibration crawling robot according to claim 6, characterized in that: The wireless circuit board includes an integrated boost circuit board (6) and a battery (7). The integrated boost circuit board (6) includes an input interface module, a contactless switch module, an MCU control module, a power amplifier module, and an output module; The input interface module is electrically connected to the battery (7); the non-contact switch module is electrically connected to the input interface module to control the current flow; the MCU control module is electrically connected to the non-contact switch module, the power amplifier module and the output module respectively; the power amplifier module is electrically connected to the non-contact switch module to amplify the voltage conducted from the battery (7); the output module is electrically connected to the power amplifier module and is externally connected to a multilayer stacked silicone rubber dielectric elastomer driver (1) to provide voltage to the multilayer stacked silicone rubber dielectric elastomer driver (1).

8. A wireless vibration crawling robot according to claim 7, characterized in that: When the multilayer stacked silicone rubber dielectric elastomer actuator (1) is subjected to voltage, the multilayer stacked silicone rubber dielectric elastomer actuator (1) in its initial state generates radial expansion, which in turn drives the spring body (2) to expand radially. The radial dimension of the spring body (2) increases, which in turn drives the overall expansion of the spring body (2), which in turn pushes the spring end caps (5) on both sides to drive the corresponding spring steel feet (3) to extend. After the voltage is removed, the multilayer stacked silicone rubber dielectric elastomer actuator (1) returns to its initial state, which in turn drives the spring body (2) to return to its original state. The radial dimension of the spring body (2) decreases, which in turn drives the overall shrinkage of the spring body (2), which in turn pushes the spring end caps (5) on both sides to drive the spring steel feet (3) to retract. The extension and retraction movement of the corresponding spring steel feet (3) is achieved by repeatedly applying periodic voltage.

9. A driving method for a wireless vibration crawling robot as described in any one of claims 5-8, characterized in that, The driving method includes: S1: Apply voltage to the multilayer stacked silicone rubber dielectric elastomer driver (1) in its initial state via a wireless circuit board to cause deformation, thereby driving the front foot to move in the forward direction and the hind foot to move in the backward direction, and the distance the hind foot moves in the backward direction is less than the distance the front foot moves in the forward direction. S2: Remove the voltage applied in step S1 through the wireless circuit board, so that the multilayer stacked silicone rubber dielectric elastomer driver (1) returns to its initial state, drives the hind foot to move in the forward direction, and the front foot to move in the backward direction, and the distance of the front foot moving in the backward direction is less than the distance of the hind foot moving in the forward direction. S3: Repeat steps S1 and S2, and the wireless vibration crawling robot moves in one direction.

10. The driving method for a wireless vibration crawling robot according to claim 9, characterized in that: Step S1 specifically involves: The wireless vibration crawling robot in its initial state is placed on the crawling surface, with its front and hind feet respectively contacting the crawling surface. Then, voltage is applied to the multilayer stacked silicone rubber dielectric elastomer actuator (1) via the wireless circuit board. The multilayer stacked silicone rubber dielectric elastomer actuator (1) in its initial state generates radial expansion, which in turn drives the spring body (2) to expand radially. The radial dimension of the spring body (2) increases, which in turn drives the overall expansion of the spring body (2), which in turn pushes the spring end caps (5) on both sides to drive the corresponding spring steel feet (3) to extend. The acute angle formed between the hind foot and the crawling surface is greater than the acute angle formed between the front foot and the crawling surface, so that the forward friction force of the hind foot on the crawling surface is greater than the backward friction force of the front foot on the crawling surface, which in turn makes the displacement distance of the front foot moving forward greater than the displacement distance of the hind foot moving backward. The wireless vibration crawling robot moves forward as a whole. Step S2 specifically involves: By removing the voltage applied in step S1 via the wireless circuit board, the multilayer stacked silicone rubber dielectric elastomer driver (1) returns to its initial state, thereby causing the spring body (2) to recover. The radial dimension of the spring body (2) shrinks, thereby causing the spring body (2) to shrink as a whole, which in turn pushes the spring end caps (5) on both sides to retract the spring steel feet (3). The direction of the friction force on the crawling surface of the front and rear feet is opposite to that in step S1, and the acute angle formed between the rear foot and the crawling surface is greater than the acute angle formed between the front foot and the crawling surface, so that the backward friction force on the crawling surface of the rear foot is less than the forward friction force on the crawling surface of the front foot, thereby causing the displacement distance of the front foot to move backward to be less than the displacement distance of the rear foot to move forward, and the wireless vibration crawling robot moves forward as a whole.

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