Flexible actuator, preparation method thereof, and actuator device

Abstract

The present application discloses a flexible actuator, a preparation method thereof, and an actuator device. The flexible actuator includes: a flexible substrate, an electrode layer, and a humidity-sensitive layer. The electrode layer is embedded in the flexible substrate and includes a first electrode terminal, a second electrode terminal, and an electrode circuit connected between the first electrode terminal and the second electrode terminal. When a voltage is applied to the first electrode terminal and the second electrode terminal, a current is generated in the electrode circuit. The humidity-sensitive layer is disposed on the first surface or the second surface of the flexible substrate and is configured to cause the flexible substrate to deform when the ambient humidity changes. This solution can enable the flexible actuator to have humidity response based on electromagnetic drive, which is beneficial for reducing the driving voltage of the flexible actuator and expanding the applicable field of the flexible actuator.

Description

Technical Field

[0001] The present application relates to the field of intelligent control technology, and in particular to a flexible actuator, a preparation method thereof, and an actuator. Background Art

[0002] Flexible actuators can be used in various fields such as industry, agriculture, consumer electronics, military, and medicine. They are characterized by high flexibility, strong environmental adaptability, and good human-computer interaction. Common driving methods include thermal drive, electric drive, gas drive, and electromagnetic drive. Among them, the electromagnetic drive method is to place the flexible actuator in a uniform magnetic field environment. As the magnitude and direction of the input current change, the magnitude and direction of the actuator deformation change under the action of the Lorentz force. Electromagnetically driven flexible actuators can generate large actuator forces, respond quickly, and have controllable deformation. They have always been a hot topic in the research of flexible actuators. However, electromagnetically driven flexible actuators also have high requirements for the magnetic environment and large driving voltage. Summary of the Invention

[0003] The present application provides a flexible actuator and a preparation method and an actuator device thereof, which can effectively improve the above-mentioned problems.

[0004] In a first aspect, an embodiment of the present application provides a flexible actuator, comprising:

[0005] Flexible substrate;

[0006] an electrode layer embedded in the flexible substrate, the electrode layer comprising a first electrode terminal, a second electrode terminal, and an electrode circuit connected between the first electrode terminal and the second electrode terminal, wherein when a voltage is applied to the first electrode terminal and the second electrode terminal, a current is generated in the electrode circuit;

[0007] The humidity-sensitive layer is disposed on the first surface or the second surface of the flexible substrate, and the humidity-sensitive layer is configured to drive the flexible substrate to deform when the ambient humidity changes.

[0008] Furthermore, the moisture-sensitive layer includes a plurality of moisture-sensitive strips arranged at intervals.

[0009] Furthermore, each of the humidity-sensitive strips at least partially overlaps with an orthographic projection of the electrode circuit on the flexible substrate.

[0010] Furthermore, a plurality of the humidity-sensitive strips are arranged in parallel, the electrode circuit includes a plurality of electrode lines arranged in parallel, and the orthographic projection of each of the humidity-sensitive strips and one of the electrode lines on the flexible substrate at least partially overlaps.

[0011] Furthermore, the flexible substrate has a first channel therein, and the first channel is filled with liquid metal to form the electrode layer.

[0012] Furthermore, the flexible substrate includes: a first flexible film layer and a second flexible film layer, the first flexible film layer is provided with a first groove on its surface, and the second flexible film layer is provided on the surface of the first flexible film layer provided with the first groove to form the first channel.

[0013] Furthermore, the flexible actuator further includes an electrode lead, which is disposed on the surface of the flexible substrate and is configured to lead the first electrode end and / or the second electrode end to an edge position of the flexible substrate.

[0014] Furthermore, the flexible actuator further comprises: a flexible cover stacked with the flexible substrate,

[0015] A second channel is provided between the flexible cover and the flexible substrate. A hole connecting the second channel and the first electrode end and / or the second electrode end is provided in the flexible substrate. The second channel and the hole are filled with liquid metal to form the electrode lead.

[0016] In a second aspect, an embodiment of the present application provides a method for preparing a flexible actuator, the method comprising:

[0017] An electrode layer is embedded in the flexible substrate, wherein the electrode layer includes a first electrode terminal, a second electrode terminal, and an electrode circuit connected between the first electrode terminal and the second electrode terminal, and when a voltage is applied to the first electrode terminal and the second electrode terminal, a current is generated in the electrode circuit;

[0018] A humidity-sensitive layer is formed on the first surface or the second surface of the flexible substrate, and the humidity-sensitive layer is configured to drive the flexible substrate to deform when the ambient humidity changes.

[0019] Furthermore, embedding the electrode layer in the flexible substrate includes:

[0020] forming a first flexible membrane layer having a first groove on its surface;

[0021] Laminating a second flexible film layer to the surface of the first flexible film layer having the first groove to form a first channel;

[0022] The first channel is filled with liquid metal to form the electrode layer.

[0023] Furthermore, filling the first channel with liquid metal to form the electrode layer includes:

[0024] forming a flexible cover having a second groove on its surface;

[0025] Opening a hole in the second flexible film layer at a position corresponding to the first electrode end and / or the second electrode end;

[0026] Laying the flexible cover on the surface of the second flexible film layer away from the first flexible film layer to form a second channel, wherein the second channel is connected to the first channel through the hole;

[0027] The liquid metal is injected into the channel formed by the first channel, the hole and the second channel to form the electrode layer and the electrode lead leading the first electrode terminal and / or the second electrode terminal to the edge of the flexible substrate.

[0028] In a third aspect, an embodiment of the present application provides an execution device, including the execution device described in the first aspect above.

[0029] The technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0030] The flexible actuator, preparation method, and actuator provided in the embodiments of the present application are configured to add a humidity-sensitive layer on the basis of electromagnetic drive by embedding an electrode layer in a flexible substrate. The humidity-sensitive layer is configured to drive the flexible substrate to deform when the ambient humidity changes. On the one hand, it can add a humidity response function on the basis of electromagnetic drive, assist the actuator in deformation, reduce the driving voltage, and improve the problem of high driving voltage under single electromagnetic drive conditions. On the other hand, it can also enable the flexible actuator to be used in environments where it is inconvenient to lay out a magnetic field, and use changes in ambient humidity to cause deformation, thereby expanding the application field of the flexible actuator.

[0031] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0033] Figure 1 This is a schematic diagram of the hierarchical structure of the flexible actuator in an embodiment of the present application;

[0034] Figure 2 This is a schematic diagram of the planar structure of the flexible actuator in the embodiment of the present application. Figure 1 ;

[0035] Figure 3 for Figure 2Schematic diagram of the structure of the EF section;

[0036] Figure 4 A schematic diagram of a working state of the flexible actuator in an embodiment of the present application;

[0037] Figure 5 This is a schematic diagram of the planar structure of the flexible actuator in the embodiment of the present application. Figure 2 ;

[0038] Figure 6 for Figure 5 Schematic diagram of the structure of the EF section;

[0039] Figure 7 This is a flow chart of a method for preparing a flexible actuator according to an embodiment of the present application;

[0040] Figure 8 This is a process flow chart for preparing a flexible actuator according to an embodiment of the present application;

[0041] Figure 9 This is a flow chart of another process for preparing a flexible actuator in an embodiment of the present application. DETAILED DESCRIPTION

[0042] The following will describe in detail exemplary embodiments of the flexible actuator, preparation method, and actuator provided by the present application with reference to the accompanying drawings. It should be noted that in the accompanying drawings, the sizes of layers and regions may be exaggerated for clarity of illustration. Although the accompanying drawings show exemplary embodiments of the present disclosure, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art. The term "and / or" appearing herein is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent three situations: A exists alone, A and B exist at the same time, and B exists alone. The term "multiple" includes two or more situations.

[0043] The embodiment of the present application provides a flexible actuator, such as Figure 1 As shown, the flexible actuator includes a flexible substrate 110 , an electrode layer 120 and a humidity-sensitive layer 130 .

[0044] The flexible substrate 110 is made of a flexible material to ensure the flexibility and stretchability of the actuator as a whole. For example, PDMS (Polydimethylsiloxane) or Ecoflex (copolyester) can be used, and this embodiment does not limit this. Compared with PDMS, Ecoflex has a larger elastic modulus, which is beneficial to improving the flexibility and stretchability of the actuator as a whole. The shape of the flexible substrate 110 can be set according to the needs of the actual application scenario. Figure 2 The square substrate shown is for illustration only and is not intended to be limiting. For example, the flexible substrate 110 may be configured to be square, strip, butterfly wing shape, or petal shape, etc., which is not limited in this embodiment.

[0045] The electrode layer 120 is embedded in the flexible substrate 110. For example, the flexible substrate 110 may include at least two stacked flexible films, namely a first flexible film layer and a second flexible film layer, and the electrode layer 120 may be disposed between the first flexible film layer and the second flexible film layer.

[0046] Specifically, such as Figure 2 As shown, the electrode layer 120 includes a first electrode terminal 121a, a second electrode terminal 121b, and an electrode circuit 121 connected between the first electrode terminal 121a and the second electrode terminal 121b. When in use, the flexible actuator can be placed in a uniform magnetic field environment. When a voltage is applied to the first electrode terminal 121a and the second electrode terminal 121b, a current in a preset direction can be generated in the electrode circuit 121. When current flows through the magnetic field, the magnetic field exerts a Lorentz force on the moving charges, causing the flexible actuator to produce a corresponding deformation under the action of the Lorentz force. As the magnitude and direction of the current in the electrode circuit 121 are different, the magnitude and direction of the deformation of the flexible actuator under the action of the Lorentz force are also different.

[0047] Therefore, when the direction of the magnetic field is constant, the path of the electrode line 121 determines the current path, which in turn determines the direction of the Lorentz force on the flexible actuator in a uniform magnetic field environment, that is, the deformation direction. Specifically, the electrode line 121 can be arranged according to the needs of the actual application scenario, and the two ends of the electrode line 121 can be used as the first electrode end 121a and the second electrode end 121b respectively. For example, it can be arranged as Figure 2 The U-shaped electrode coil shown has its two ends serving as a first electrode end 121a and a second electrode end 121b, respectively. Alternatively, a plurality of electrode lines 121 extending in a specified direction and parallel to each other may be arranged, and each electrode line 121 has an independent first electrode end 121a and a second electrode end 121b. This embodiment does not impose any restrictions on this.

[0048] For example, the electrode circuit 121 can be a metal wire with a low resistance, such as a copper resistance wire or a platinum resistance wire, or a patterned conductive material film layer, the specific pattern of which is determined by the desired shape of the electrode circuit 121. For example, a metal wire or a patterned conductive material film layer can be disposed on the surface of the first flexible film layer to form the electrode circuit 121, and then a second flexible film layer can be attached to the surface of the first flexible film layer with the electrode circuit 121 disposed thereon, thereby wrapping the electrode circuit 121 and achieving a flattened surface of the flexible substrate 110.

[0049] To improve the overall flexibility and stretchability of the actuator, in an optional embodiment, a first channel may be provided within the flexible substrate 110, and the electrode circuit 121, i.e., the electrode layer 120, may be formed by filling the first channel with liquid metal. For example, the first channel may be provided between the first flexible film layer and the second flexible film layer. For example, a patterned first groove may be provided on the surface of the first flexible film layer, and the second flexible film layer may be attached to the surface of the first flexible film layer having the first groove provided thereon. This may form the first channel between the first and second flexible film layers, and liquid metal may then be injected into the first channel to form the electrode circuit 121.

[0050] Furthermore, since the electrode layer 120 is embedded in the flexible substrate 110, in order to flexibly set the shape of the electrode circuit 121 and facilitate the connection of the first electrode terminal 121a and the second electrode terminal 121b to an external control system, such as Figure 2 and Figure 3 As shown, the flexible actuator provided by the embodiment of the present application may further include: an electrode lead 122, the electrode lead 122 being arranged on the surface of the flexible substrate 110, and the first electrode end 121a and / or the second electrode end 121b of the electrode circuit 121 embedded in the flexible substrate 110 are led out to the edge position of the flexible substrate 110 through the electrode lead 122, that is, to the edge position of the flexible actuator. The setting position and setting method of the electrode lead 122 can be set according to the needs of the actual application scenario. For example, the electrode lead 122 can be set on the surface of the second flexible film layer away from the first flexible film layer. In a specific implementation, if either the first electrode end 121a or the second electrode end 121b is set at a non-edge position of the flexible actuator, or if both are set at a non-edge position of the flexible actuator, by setting an electrode lead 122 connected to the corresponding electrode end, it can be led out to the edge position to facilitate connection.

[0051] For example, when the electrode circuit 121 adopts the above-mentioned U-shaped electrode coil, the first electrode end 121a is located at the center of the "U-shape", and the second electrode end 121b extends to the edge of the flexible actuator. At this time, it is necessary to set an electrode lead 122 to lead the first electrode end 121a to the edge of the flexible actuator, and the electrode lead 122 is insulated from the other parts of the coil.

[0052] The material and process of the electrode lead 122 can be the same as or different from that of the electrode line 121. As an embodiment, the electrode lead 122 can also be made of metal wire or conductive material film. Figure 3 As shown, holes can be opened on the flexible substrate 110, such as the second flexible film layer, at locations corresponding to the first electrode terminal 121a and / or the second electrode terminal 121b, so that the electrode lead 122 can be electrically connected to the first electrode terminal 121a and / or the second electrode terminal 121b through the hole 113. It should be noted that if the electrode circuit 121 is made of liquid metal and the electrode lead 122 is made of metal wire or a conductive material film layer, then after the metal wire or conductive material is connected through the hole 113, an uncured elastomer can be used to seal the area around the insertion hole to prevent liquid metal leakage.

[0053] As another embodiment, the electrode leads 122 may be made of liquid metal. In this case, the flexible actuator further includes a flexible cover laminated with the flexible substrate 110, with a second channel formed between the flexible cover and the flexible substrate 110. The flexible substrate 110 includes a hole connecting the second channel to the first electrode terminal 121a and / or the second electrode terminal 121b. The second channel and the hole are both filled with liquid metal, forming the electrode leads 122.

[0054] For example, the flexible substrate 110 includes the aforementioned first and second flexible film layers. A second groove corresponding to the desired electrode lead 122 can be provided on the surface of the flexible cover. A hole is opened in the second flexible film layer at a position corresponding to the first electrode terminal 121a and / or the second electrode terminal 121b. The surface of the flexible cover with the second groove is aligned and attached to the surface of the second flexible film layer away from the first flexible film layer. The second flexible film layer can be a flat film layer. In this way, a second channel is formed between the second flexible film layer and the flexible cover. The second channel is connected to the first channel through the aforementioned hole 113, forming a channel. Liquid metal is injected into the channel to fill the entire first and second channels, thereby forming the aforementioned electrode layer 120 and electrode lead 122.

[0055] It should be noted that the flexible cover and the flexible substrate 110 may be made of the same material or different materials. For example, both may be made of Ecoflex material.

[0056] Furthermore, the humidity-sensitive layer 130 is configured to cause the flexible substrate 110 to deform when the ambient humidity changes. Specifically, the material of the humidity-sensitive layer 130 is a humidity-sensitive material whose length or volume responds to humidity. The humidity-sensitive material can produce a physical or chemical reaction with water molecules. When the humidity of the surrounding environment changes, the length or volume changes. For example, when the humidity increases, the length or volume of the material expands, and when the humidity decreases, the length or volume of the material shrinks. For example, the humidity-sensitive layer 130 can be made of polyethylene oxide, or other humidity-sensitive materials with similar functions, such as hydrogels, polyvinyl alcohol (PVA), acetate fibers, styrenes, polyimides and their derivatives, which are humidity-responsive materials in volume. This embodiment does not limit this.

[0057] For example, for the sake of convenience, Figure 1 The two surfaces of the flexible actuator shown in FIG are respectively referred to as the upper and lower surfaces, and the four side surfaces adjacent to the upper and lower surfaces are respectively referred to as the front side (such as Figure 2 E side shown in), rear side (as shown in Figure 2 F side shown in), left side (as shown in Figure 2 C side shown in the figure) and right side (as shown in the figure) Figure 2 In one application scenario, the working principle of the flexible actuator can be as follows: Figure 4 As shown, Figure 4 Figures (a), (b), and (c) all indicate Figure 2 In operation, the flexible actuator is placed in a uniform magnetic field (magnetic field strength is represented by B), with its right side fixed. The first electrode terminal 121a and the second electrode terminal 121b are connected to a power source, respectively, so that the current I in the electrode circuit 121 forms a loop in the magnetic field.

[0058] According to the left-hand rule, when current I flows through magnetic field B, it generates an upward Lorentz force F1 perpendicular to the upper and lower surfaces at the left end of the flexible actuator, and a downward Lorentz force F2 perpendicular to the upper and lower surfaces at the right end. Simultaneously, the current generates heat in the electrode circuit 121, heating the flexible actuator structure and the surface environment, resulting in a slight decrease in humidity. The surface humidity-sensitive layer 130 contracts, generating a tensile force on the film surface and assisting in deformation of the flexible actuator. Consequently, under the combined force of the Lorentz force and the contraction of the humidity-sensitive layer 130, the left side of the flexible actuator bends upward relative to the right side. Thus, the humidity response of the humidity-sensitive layer 130 assists in the deformation of the flexible actuator caused by the Lorentz force, thereby achieving a desired deformation while reducing the input electromagnetic drive voltage.

[0059] In another application scenario, the flexible actuator is placed flat in a non-magnetic field environment, and the humidity of the environment changes according to a preset rule. When the humidity decreases, the humidity-sensitive layer 130 on the surface of the flexible actuator will shrink, showing a deformation effect in which the center is concave downward and the surrounding areas are curved upward. Conversely, when the humidity increases, the humidity-sensitive layer 130 on the surface of the flexible actuator will expand, showing a deformation effect in which the center bulges upward and the surrounding areas are curved downward. In this way, the flexible actuator can be controlled to achieve the desired deformation effect simply by using the humidity change of the environment, or the humidity change in the environment can be sensed by the deformation effect presented by the flexible actuator. The specific setting can be based on actual needs.

[0060] Therefore, the flexible actuator provided in this embodiment has an increased humidity response function by providing a humidity-sensitive layer 130. On the one hand, it can assist the actuator in deformation based on electromagnetic drive, reduce the driving voltage, and improve the problem of high driving voltage under single electromagnetic drive conditions. On the other hand, it can also enable the flexible actuator to be used in environments where it is inconvenient to deploy a magnetic field, using changes in environmental humidity to cause deformation, thereby expanding the applicable field of the flexible actuator.

[0061] In a specific implementation, the humidity-sensitive layer 130 can be disposed on the first surface 111 of the flexible substrate 110 or on the second surface 112 opposite the first surface 111. The specific location can be determined based on actual needs. For example, if the electrode leads 122 are disposed on the first surface 111 of the flexible substrate 110, and the electrode leads 122 are metal wires or conductive film layers, since the electrode leads 122 are relatively thin, the humidity-sensitive layer 130 can be disposed on the first surface 111, covering the electrode leads 122. This not only ensures the inherent humidity-sensitive properties of the layer, but also protects the electrode leads 122. For another example, when the electrode lead 122 is made by filling the second channel between the first surface 111 of the flexible substrate 110 and the flexible cover with liquid metal, and in order to minimize the impact of the flexible cover on the overall flexibility and stretchability, the flexible cover does not cover the entire surface of the flexible substrate 110, but only covers the area where the second channel is to be formed. Since the flexible cover has a certain thickness, which is much greater than the thickness of the metal wire or the conductive material film layer, in order to make the actuator have better humidity response characteristics, the humidity sensitive layer 130 can be set on the second surface 112 of the flexible substrate 110 opposite to the first surface 111.

[0062] The humidity sensitive layer 130 can be provided as a whole layer, or can also be provided in different regions. Figure 5As shown, the humidity-sensitive layer 130 includes a plurality of spaced-apart humidity-sensitive strips 131. The shapes and sizes of these humidity-sensitive strips 131 can be identical or different, depending on the specific needs of the application. Since the surface humidity-sensitive layer 130 is separated, the overall Poisson's ratio of the actuator can be adjusted, which helps reduce the stiffness of the entire flexible actuator and improve its overall flexibility and stretchability.

[0063] Furthermore, considering that the heat generated by the electrode circuit 121 under the action of current significantly affects the surface humidity of the electrode circuit 121 and the surrounding area, in order to optimize the distribution of the surface tension of the humidity-sensitive layer 130, humidity-sensitive strips 131 can be arranged corresponding to the electrode circuit 121. Specifically, each humidity-sensitive strip 131 at least partially overlaps with the orthographic projection of the electrode circuit 121 on the flexible substrate 110. To further improve overall flexibility and stretchability, the multiple humidity-sensitive strips 131 can be arranged in parallel, with the specific layout and extension direction determined by the electrode circuit 121 and the desired deformation direction of the actuator.

[0064] In an optional embodiment, the electrode circuit 121 includes multiple parallel electrode lines, and each humidity-sensitive strip 131 may at least partially overlap with the orthographic projection of an electrode line on the flexible substrate 110, so as to further optimize the distribution of surface tension of the humidity-sensitive layer 130. For example, the humidity-sensitive strips 131 may be provided in a one-to-one correspondence with the electrode lines, and the humidity-sensitive strips 131 may cover the corresponding electrode lines, that is, the orthographic projections of the electrode lines on the flexible substrate 110 are located within the orthographic projections of the corresponding humidity-sensitive strips 131 on the flexible substrate 110.

[0065] like Figure 5 As shown, taking the above-mentioned U-shaped electrode coil as an example, the U-shaped electrode coil includes multiple transverse electrode lines and multiple longitudinal electrode lines. For example, the humidity-sensitive strip 131 can be set corresponding to the transverse electrode line, such as covering the transverse electrode line, or the humidity-sensitive strip 131 can also be set corresponding to the longitudinal electrode line, such as covering the longitudinal electrode line, and the specific setting is based on the needs of the actual scene.

[0066] For example, in one application scenario, it is necessary to fix one side of the flexible actuator, and realize the up and down bending of the flexible actuator under the action of electromagnetic drive and humidity response. In this case, the extension direction of the humidity sensitive strip 131 can be parallel to the bending reference line to reduce the magnitude of the force required to achieve the bending. Figure 6As shown, if the rear side is fixed, the current in the electrode circuit 121 flows through a uniform magnetic field environment, generating a Lorentz force F3 perpendicular to the upper and lower surfaces and in an upward direction at the upper end of the flexible actuator, and a Lorentz force F4 perpendicular to the upper and lower surfaces and in a downward direction at the right end of the flexible actuator, causing the front side of the flexible actuator to bend upward relative to the rear side. Then, the humidity-sensitive strip 131 can extend in the lateral direction, i.e., the width direction of the front and rear sides, and cover the lateral electrode line, as shown in FIG. Figure 5 As shown; of course, if the right side is fixed, the humidity-sensitive strip 131 can extend along the longitudinal direction, ie, the width direction of the left and right sides, and cover the longitudinal electrode line.

[0067] In addition, the present application also provides a method for preparing a flexible actuator, which is used to prepare the flexible actuator. Figure 7 As shown, the method may include the following steps:

[0068] Step S701: embedding an electrode layer in a flexible substrate, wherein the electrode layer includes a first electrode terminal, a second electrode terminal, and an electrode circuit connected between the first electrode terminal and the second electrode terminal. When a voltage is applied to the first electrode terminal and the second electrode terminal, a current is generated in the electrode circuit.

[0069] Step S702 : forming a humidity-sensitive layer on the first surface or the second surface of the flexible substrate, wherein the humidity-sensitive layer is configured to cause the flexible substrate to deform when the ambient humidity changes.

[0070] The following mainly describes the preparation process of two electrode layer 120 materials. It should be noted that the processes used in the following preparation steps are only for illustration purposes. In other embodiments of the present application, other applicable processes may also be used, and this embodiment does not limit this.

[0071] The first type is that the electrode circuit 121 is a metal wire or a conductive material film. Figure 8 As shown in Figures (a), (b), (c), and (d), the specific preparation process may include:

[0072] Mix part A (main agent) and part B (cross-linking agent) of PDMS in a ratio of 10:1. After stirring thoroughly, place the PDMS glue in a vacuum device to remove bubbles inside the colloid.

[0073] Then, the PDMS colloid is evenly coated on the surface of the substrate using a coating machine, and then heated and cured using a hot plate to form the first flexible film layer 201 .

[0074] Then, if Figure 8As shown in Figure (a), an electrode circuit 121 is formed on the upper surface of the first flexible film layer 201. For example, taking the electrode circuit 121 as a U-shaped coil, the center point of the first flexible film layer 201 can be used as the first electrode end 121a, extending along the U-shaped coil toward the edge of the first flexible film layer 201, and ending at the second electrode end 121b. For example, the electrode circuit 121 can be formed using metal wire, such as copper resistance wire or platinum resistance wire, or can be formed by depositing a conductive film, such as a metal film or a transparent conductive film layer, using a magnetron sputtering process and patterning it.

[0075] The second flexible film layer 202 is prepared again using PDMS glue and is bonded to the first flexible film layer 201. Figure 8 As shown in FIG. 1( b ), the electrode circuit 121 is completely coated to complete the preparation of the electrode layer 120 . At this time, the flexible substrate 110 includes a first flexible film layer 201 and a second flexible film layer 202 , and the electrode layer 120 is embedded between the first flexible film layer 201 and the second flexible film layer 202 .

[0076] Furthermore, in order to lead out the first electrode terminal 121a, a hole may be opened in the center of the second flexible film, such as Figure 8 As shown in FIG. 1( b ), as a lead interface for the first electrode terminal 121 a, an electrode lead 122 is prepared on the surface of the second flexible film away from the first flexible film layer 201. The electrode lead 122 is connected to the first electrode terminal 121 a through the lead interface and extends to the edge of the second flexible film layer 202 to achieve the extraction of the first electrode terminal 121 a. Figure 8 As shown in Figure (c).

[0077] On this basis, if Figure 8 As shown in Figure (d), the surface of the second flexible film where the electrode leads 122 are provided, i.e., the first surface 111 of the flexible substrate 110, can be uniformly coated with a moisture-sensitive material such as polyethylene oxide to form a moisture-sensitive layer 130, which assists in actuator deformation while also protecting the electrode leads 122. Alternatively, a moisture-sensitive material such as polyethylene oxide can be coated on the surface of the first flexible film layer 201 away from the second flexible film layer 202, i.e., the second surface 112 of the flexible substrate 110, to form the moisture-sensitive layer 130, and a protective layer can be provided on the electrode leads 122 to protect them. The specific structure of the moisture-sensitive layer 130 can be found in the relevant description of the first aspect above and will not be repeated here.

[0078] The second method is to use liquid metal for the electrode circuit 121. In this case, step S701 may include: forming a first flexible film layer 201 having a first groove on its surface; attaching a second flexible film layer 202 to the surface of the first flexible film layer 201 having the first groove to form a first channel 301; and filling the first channel 301 with liquid metal to form the electrode layer 120. Furthermore, when it is necessary to provide an electrode lead 122 made of liquid metal, the above-mentioned step of filling the first channel 301 with liquid metal to form the electrode layer 120 may include: forming a flexible cover 203 having a second groove on the surface; opening a hole in the second flexible film layer 202 at a position corresponding to the first electrode end 121a and / or the second electrode end 121b; attaching the flexible cover 203 to the surface of the second flexible film layer 202 away from the first flexible film layer 201 to form a second channel 302, and the second channel 302 is connected to the first channel 301 through the hole 113; injecting liquid metal into the channel formed by the first channel 301, the hole 113 and the second channel 302 to form the electrode layer 120, and leading the first electrode end 121a and / or the second electrode end 121b to the electrode lead 122 at the edge of the flexible substrate 110.

[0079] Also, take the electrode circuit 121 as an example of a U-shaped coil. Figure 9 As shown in Figures (a), (b), (c), and (d), the specific preparation process may include:

[0080] A first mold corresponding to the first groove and a second mold corresponding to the second groove are prepared using 3D printing. The printing accuracy determines the channel width and depth of the first groove and the second groove. The pattern of the first groove is set according to the electrode circuit 121, and the pattern of the second groove is set according to the electrode lead 122.

[0081] Then, Part A and Part B of Ecoflex are mixed in a 1:1 ratio and placed in a vacuum oven for degassing to produce an elastomer. Subsequently, the uncured elastomer is poured into the first mold and the second mold, respectively, and the curing temperature and time are adjusted according to the intended use. After curing, the molds are removed, forming a first flexible film layer 201 with a first groove and a flexible cover 203 with a second groove. A coating machine is used to evenly apply the Ecoflex colloid to the substrate surface, and then a hot plate is used to heat and cure it to form a second flexible film layer 202.

[0082] like Figure 9 As shown in FIG. 1 (a), the second flexible film layer 202 is attached to the surface of the first flexible film layer 201 having the first groove, forming a flexible shell having a first U-shaped channel 301 inside. Figure 9As shown in Figure (b), a hole is opened on the second flexible film layer 202, and the hole position is the position corresponding to the first electrode end 121a in the first channel 301. The flexible cover 203 is attached to the surface of the second flexible film layer 202 away from the first flexible film layer 201 to form the second channel 302, and the second channel 302 is connected to the first channel 301 at the position where the first electrode end 121a is located.

[0083] Then, if Figure 9 As shown in FIG. 1 , liquid metal is injected into the channel formed by the first channel 301, the hole 113 and the second channel 302 using a syringe to form a U-shaped electrode circuit 121 and an electrode lead 122 for leading out the first electrode terminal 121a located at the center.

[0084] At this time, considering that the flexible cover 203 has a certain thickness, in order to ensure the flatness of the humidity sensitive layer 130 and achieve better humidity sensitive response characteristics, a layer of humidity sensitive material such as polyethylene oxide can be coated on the surface of the first flexible film layer 201 away from the second flexible film layer 202, that is, the second surface 112 of the flexible substrate 110, to form the humidity sensitive layer 130. Figure 9 The specific structure of the humidity sensitive layer 130 can refer to the related description of the first aspect above, which will not be repeated here.

[0085] In addition, the embodiment of the present application further provides an execution device, including: the above-mentioned flexible actuator. Of course, in addition to the flexible actuator, the execution device may also include an execution body, and the flexible actuator is connected to the execution body.

[0086] Specifically, actuators can be of various types, and the connection location and method of the flexible actuator can be customized based on actual needs. For example, the actuator can be a bionic butterfly, with one side of the flexible actuator connected to the actuator body, which serves as the butterfly's torso, acting as the wings. The bionic butterfly is placed in a uniform magnetic field, and the flexible actuator's deformation is controlled to simulate the effect of the butterfly flapping its wings. The actuator can also be a bionic flower, with one side of the flexible actuator connected to the actuator body, which serves as the flower's trunk, acting as the petals. The flexible actuator's deformation is controlled to simulate the effect of the flower blooming. The actuator can be a bionic robotic arm or robot, with flexible actuators applied to its fingers or joints to enhance its flexibility. The actuator can be a component that needs to be flipped, with the actuator body being a substrate. The flexible actuator is stacked and attached to the substrate, driving the substrate to flip. Alternatively, the actuator can be a humidity sensor, which uses the deformation of the flexible actuator in the environment to detect humidity data.

[0087] Of course, in addition to the types listed above, the execution device can also be other types of devices, which is not limited in this embodiment.

[0088] The above description does not provide detailed explanations of technical details such as the patterning of each layer of the product. However, those skilled in the art will appreciate that various technical means can be used to form layers, regions, and the like in desired shapes. Furthermore, those skilled in the art may devise methods that differ from those described above to achieve the same structure. Although each embodiment has been described separately, this does not mean that the measures in each embodiment cannot be advantageously combined.

[0089] In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures, and techniques are not shown in detail so as not to obscure the understanding of this description.

[0090] In addition, it should be understood by those skilled in the art that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present disclosure is limited to these examples. Based on the concept of the present disclosure, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of different aspects of one or more embodiments of the present specification as described above, which are not provided in detail for the sake of simplicity.

[0091] Although the preferred embodiments of this specification have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of this specification.

Claims

1. A flexible actuator, characterized in that: include: Flexible substrate; an electrode layer embedded in the flexible substrate, the electrode layer comprising a first electrode terminal, a second electrode terminal, and an electrode circuit connected between the first electrode terminal and the second electrode terminal, wherein when a voltage is applied to the first electrode terminal and the second electrode terminal, a current is generated in the electrode circuit; a humidity-sensitive layer, disposed on the first surface or the second surface of the flexible substrate, wherein the humidity-sensitive layer is configured to cause the flexible substrate to deform when the ambient humidity changes; The orthographic projection of the electrode circuit on the flexible substrate is located within the orthographic projection range of the humidity-sensitive layer on the flexible substrate; or, the humidity-sensitive layer includes a plurality of humidity-sensitive strips arranged at intervals, the plurality of humidity-sensitive strips are arranged in parallel, the electrode circuit includes a plurality of parallelly arranged electrode lines, the extension direction of the electrode lines is the same as the extension direction of the humidity-sensitive strips, and each of the humidity-sensitive strips at least partially overlaps with the orthographic projection of an electrode line on the flexible substrate.

2. The flexible actuator according to claim 1, characterized in that The flexible substrate has a first channel therein, and the first channel is filled with liquid metal to form the electrode layer.

3. The flexible actuator according to claim 2, characterized in that The flexible substrate includes a first flexible film layer and a second flexible film layer. The first flexible film layer is provided with a first groove on its surface. The second flexible film layer is provided on the surface of the first flexible film layer provided with the first groove to form the first channel.

4. The flexible actuator according to any one of claims 1 to 3, characterized in that: It also includes an electrode lead, which is arranged on the surface of the flexible substrate and is configured to lead the first electrode end and / or the second electrode end to an edge position of the flexible substrate.

5. The flexible actuator according to claim 4, characterized in that Also includes: a flexible cover body stacked with the flexible substrate, A second channel is provided between the flexible cover and the flexible substrate. A hole connecting the second channel and the first electrode end and / or the second electrode end is provided in the flexible substrate. The second channel and the hole are filled with liquid metal to form the electrode lead.

6. A method for preparing a flexible actuator, characterized in that: The method comprises: An electrode layer is embedded in the flexible substrate, wherein the electrode layer includes a first electrode terminal, a second electrode terminal, and an electrode circuit connected between the first electrode terminal and the second electrode terminal, and when a voltage is applied to the first electrode terminal and the second electrode terminal, a current is generated in the electrode circuit; forming a humidity-sensitive layer on the first surface or the second surface of the flexible substrate, wherein the humidity-sensitive layer is configured to cause the flexible substrate to deform when the ambient humidity changes; The orthographic projection of the electrode circuit on the flexible substrate is located within the orthographic projection range of the humidity-sensitive layer on the flexible substrate; or, the humidity-sensitive layer includes a plurality of humidity-sensitive strips arranged at intervals, and the plurality of humidity-sensitive strips are arranged in parallel. The electrode circuit includes a plurality of parallelly arranged electrode lines, and the extension direction of the electrode lines is the same as the extension direction of the humidity-sensitive strips. Each of the humidity-sensitive strips at least partially overlaps with the orthographic projection of one of the electrode lines on the flexible substrate.

7. The method according to claim 6, characterized in that The method of embedding an electrode layer in a flexible substrate includes: forming a first flexible membrane layer having a first groove on its surface; Laminating a second flexible film layer to the surface of the first flexible film layer having the first groove to form a first channel; The first channel is filled with liquid metal to form the electrode layer.

8. The method according to claim 7, characterized in that Filling the first trench with liquid metal to form the electrode layer comprises: forming a flexible cover having a second groove on its surface; Opening a hole in the second flexible film layer at a position corresponding to the first electrode end and / or the second electrode end; Laying the flexible cover on the surface of the second flexible film layer away from the first flexible film layer to form a second channel, wherein the second channel is connected to the first channel through the hole; The liquid metal is injected into the channel formed by the first channel, the hole and the second channel to form the electrode layer and the electrode lead leading the first electrode terminal and / or the second electrode terminal to the edge of the flexible substrate.

9. An execution device, characterized in that: include: The flexible actuator according to any one of claims 1 to 5.

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