Liquid-gas phase change flexible actuator based on solid-liquid phase change regulation and method thereof

Abstract

The application discloses a liquid-gas phase change flexible actuator based on solid-liquid phase change regulation and control. The actuator comprises a driving layer, a heat insulation layer and a variable stiffness layer which are all in the shape of a strip and are closely and sequentially arranged in layers, and each two adjacent layers among the driving layer, the heat insulation layer and the variable stiffness layer are connected and fixed. The driving layer is driven to deform by driving heating wires, and the variable stiffness layer adjusts the stiffness of the deformation of different positions of the driving layer by stiffness regulation heating wires. The deformation and adjustment of the liquid-gas phase change flexible actuator in any shape are realized by cooperation of the driving layer and the variable stiffness layer, so that different working modes are realized. The liquid-gas phase change flexible actuator based on solid-liquid phase change regulation and control can realize repeated reversible regulation and deformation of the actuator, has the advantages of various deformation forms, fast response speed, low energy consumption for maintaining deformation, and has great application prospect.

Description

Technical Field

[0001] This invention relates to a flexible actuator in the field of soft robots, specifically to a liquid-gas phase change flexible actuator and method based on solid-liquid phase change regulation. Background Technology

[0002] Flexible actuators, as the core of soft robotics technology, have demonstrated significant application value in fields such as robotics, human-computer interaction, medicine, and aerospace. Existing flexible actuators are based on various flexible actuation mechanisms, including fluid actuation, shape memory alloy actuation, dielectric elastomer actuation, and liquid-gas phase change actuation. Among these, liquid-gas phase change actuation flexible actuators offer advantages such as large output deformation, high output pressure, and quiet operation. However, existing liquid-gas phase change actuation flexible actuators still suffer from limitations such as a relatively singular deformation form. The deformation form cannot be changed after manufacturing, and they can only achieve uniform overall deformation, not localized deformation control at specific locations. Furthermore, since liquid-gas phase change is thermally driven, existing liquid-gas phase change actuation flexible actuators suffer from slow deformation response speed. Additionally, maintaining deformation requires sustained energy output, resulting in high energy consumption for deformation holding. Summary of the Invention

[0003] The technical problem solved by this invention is to provide a liquid-gas phase change flexible actuator based on solid-liquid phase change control. By controlling the deformation generated by liquid-gas phase change drive through solid-liquid phase change control, this invention solves the problems of existing liquid-gas phase change driven flexible actuators having relatively simple deformation forms, slow deformation response speed, and high energy consumption for deformation holding. This invention provides a technical solution that can realize rich and adjustable deformation forms, rapid deformation, and energy-free deformation holding, and achieves reversible and diverse deformation control and local deformation control.

[0004] The technical solution adopted in this invention is: I. Flexible Liquid-Gas Phase Change Actuator Based on Solid-Liquid Phase Change Regulation It includes a driving layer, a heat insulation layer, and a variable stiffness layer, all of which are strip-shaped and arranged in close succession. Each adjacent pair of the driving layer, heat insulation layer, and variable stiffness layer is connected and fixed. Both the driving layer and the variable stiffness layer are equipped with electrically heated components. The driving layer is driven to deform by the electrically heated components, and the variable stiffness layer adjusts the stiffness of the deformation at different positions of the driving layer by the electrically heated components. The driving layer and the variable stiffness layer work together to realize the deformation and adjustment of the liquid-gas phase change flexible actuator in any shape. The driving layer mainly consists of a first driving layer shell, a liquid-gas phase change working fluid, a driving heating wire, a second driving layer shell, and a sheet-like fabric restraint layer, all arranged in a tightly stacked manner and in strip shape. The second driving layer shell is bonded to the fabric restraint layer, and the first driving layer shell is arranged on top of the second driving layer shell. A relatively closed strip-shaped driving cavity is formed between the first driving layer shell and the second driving layer shell. The driving heating wire is disposed in the strip-shaped driving cavity and filled with the liquid-gas phase change working fluid. The first driving layer shell is configured as a toothed shell structure. The driving heating wire extends and is arranged entirely within the strip-shaped driving shell and bends through each tooth of the toothed shell structure. The liquid-gas phase change working fluid fills the space inside the strip-shaped driving cavity except for the driving heating wire. The upper surface of the second driving layer shell has a strip-shaped groove parallel to its own strip direction.

[0005] The strip-shaped grooves on the upper surface of the second driving layer shell are used to connect the various toothed cavities in the first driving layer shell, allowing the liquid-gas phase change working fluid to flow freely within them. The fabric restraining layer is used to restrict the elongation of the driving layer in the length direction, ensuring that the bending deformation occurs biased towards the fabric restraining layer.

[0006] The first driving layer shell has hollow hole structures at both ends. The driving heating wire passes through the hole structures at both ends of the first driving layer shell and is connected to an external power source, and is used to heat the liquid-gas phase change working fluid.

[0007] The variable stiffness layer includes a first variable stiffness layer shell, a stiffness-regulating heating wire, a solid-liquid phase change working fluid, and a second variable stiffness layer shell, all of which are strip-shaped. The top surface of the second variable stiffness layer shell has a strip-shaped groove along the strip-shaped direction of the variable stiffness layer. The first variable stiffness layer shell is connected to the groove opening of the second variable stiffness layer shell. A relatively closed strip-shaped variable stiffness cavity is formed between the first and second drive layer shells. The stiffness-regulating heating wire is embedded inside the first and second drive layer shells outside the strip-shaped variable stiffness cavity. The strip-shaped variable stiffness cavity is filled with a solid-liquid phase change working fluid.

[0008] The stiffness-regulating heating wire consists of multiple annular heating wires that are equally spaced and independent along the strip direction of the variable stiffness layer. Each annular heating wire is arranged around the outer periphery of the strip-shaped variable stiffness cavity in the circumferential direction. Each stiffness-regulating heating wire is used to independently control the temperature of the solid-liquid phase change working fluid. Each of the stiffness-regulating heating wires passes through the outer shell of the variable stiffness layer and is connected to an external power source.

[0009] By energizing a stiffness-regulating heating wire at a certain location, a local solid-liquid phase change occurs in the working fluid at that stiffness-regulating heating wire, thereby softening the position of the stiffness-regulating heating wire in the variable stiffness layer. This is used to regulate the deformation stiffness of the liquid-gas phase change flexible actuator at each strip direction position when the drive layer deforms.

[0010] The liquid-gas phase change flexible actuator also includes a fixing clamp, which is located on one side perpendicular to the strip direction of the drive layer and is fixedly connected to the drive layer, the heat insulation layer and the variable stiffness layer.

[0011] When the driving heating wire is energized and heated, it drives the liquid-gas phase change working medium in the strip-shaped driving cavity to undergo a liquid-gas phase change for driving, thereby driving the overall deformation of the liquid-gas phase change flexible actuator; the variable stiffness layer uses the local solid-liquid phase change of the solid-liquid phase change working medium to control the stiffness at various positions in the strip direction, thereby regulating the deformation stiffness of the liquid-gas phase change flexible actuator.

[0012] The upper surface of the insulation layer is provided with a column group on each side along its strip direction. Each column group includes multiple columns. The columns in each column group are symmetrically distributed and extend along its strip direction at equal intervals to form a column array structure. The insulation layer is used to reduce thermal interference between the driving layer and the variable stiffness layer.

[0013] II. Solid-Liquid Phase Change Regulation Method for Liquid-Gas Phase Change Flexible Actuators Methods for determining the control actuator to achieve four different operating modes based on the following conditions: Deformation control working mode: First, the variable stiffness layer is electrically heated to control the deformation stiffness of the liquid-gas phase change flexible actuator at various positions in the strip direction. Then, the driving layer is electrically heated to drive the overall deformation of the liquid-gas phase change flexible actuator, so as to achieve any expected deformation state. Rapid Deformation Working Mode: First, the driving layer is energized and heated to regulate the liquid-gas phase change flexible actuator for energy storage. Since the variable stiffness layer is in a high stiffness state, the liquid-gas phase change flexible actuator does not bend or deform at this time. During this stage, the expansion of the driving layer due to the liquid-gas phase change is converted into elastic potential energy and stored in the structure of the liquid-gas phase change flexible actuator. Then, the variable stiffness layer is energized and heated. At this time, due to the local softening of the variable stiffness layer, the elastic potential energy stored in the actuator structure in the previous stage is suddenly released, regulating the deformation stiffness of the liquid-gas phase change flexible actuator at various positions in the strip direction. The driving layer rapidly deforms in the area softened by the energized and heated variable stiffness layer, causing the liquid-gas phase change flexible actuator to rapidly deform in the area softened by the energized and heated variable stiffness layer. The liquid-gas phase change flexible actuator achieves the rapid deformation working mode. Shape locking working mode: For a liquid-gas phase change flexible actuator in a deformed state, the temperature of the variable stiffness layer is first cooled to solidify the variable stiffness layer, and then the drive layer is cooled and liquefied, so that the shape protection of the liquid-gas phase change flexible actuator is locked, thereby realizing the shape locking working mode. Restoring the initial working mode: For a liquid-gas phase change flexible actuator that is in a deformed state, first cool the drive layer to liquefy it and restore its initial shape, and then cool the temperature of the variable stiffness layer to solidify it, thereby restoring the initial working mode.

[0014] More specifically, the controlled deformation working mode is as follows: by heating the stiffness control heating wire of the variable stiffness layer at a certain position, the solid-liquid phase change working medium at the position of the stiffness control heating wire is further controlled to undergo solid-liquid phase change, and then the driving heating wire is heated to control the liquid-gas phase change working medium of the driving layer to undergo liquid-gas phase change as a whole, so that the liquid-gas phase change flexible actuator is deformed as a whole, and the liquid-gas phase change flexible actuator realizes the controlled deformation working mode. More specifically, the rapid deformation working mode involves heating the driving heating wire of the driving layer to control the liquid-gas phase change working fluid to undergo a liquid-gas phase change, thereby regulating the driving layer to enable the liquid-gas phase change flexible actuator to store energy. Since the variable stiffness layer is in a high stiffness state, the actuator as a whole does not bend or deform. During this stage, the volume expansion of the driving layer due to the liquid-gas phase change is converted into elastic potential energy and stored in the actuator structure. Then, heating the stiffness regulating heating wire at a certain position further controls the solid-liquid phase change working fluid at the location of the stiffness regulating heating wire to undergo a solid-liquid phase change, causing the variable stiffness layer to soften at this location. The driving layer rapidly deforms in the area softened by the electric heating of the variable stiffness layer, causing the liquid-gas phase change flexible actuator to rapidly deform in the area softened by the electric heating of the variable stiffness layer. The liquid-gas phase change flexible actuator achieves the rapid deformation working mode. More specifically, the shape locking working mode is as follows: for a liquid-gas phase change flexible actuator in a deformed state, while maintaining the liquid-gas phase change working medium of the driving layer in a vaporized driving state, the solid-liquid phase change working medium of the variable stiffness layer is cooled and solidified, and then the liquid-gas phase change working medium of the driving layer is cooled and liquefied, so that the shape locking of the driving layer causes the shape protection locking of the liquid-gas phase change flexible actuator, thereby realizing the shape locking working mode. More specifically, the restoration of the initial working mode involves: for a liquid-gas phase change flexible actuator in a deformed state, while maintaining the solid-liquid phase change working medium of the variable stiffness layer in a liquefied driving state, cooling and liquefying the liquid-gas phase change working medium of the driving layer to restore the driving layer to its initial shape; then cooling the solid-liquid phase change working medium of the variable stiffness layer to solidify the solid-liquid phase change working medium, thereby realizing the restoration of the initial working mode.

[0015] The beneficial effects of this invention are: 1. The liquid-gas phase change actuator of the present invention is a liquid-gas phase change flexible actuator based on solid-liquid phase change regulation. Compared with the existing actuators based on liquid-gas phase change drive, it can repeatedly and reversibly adjust the deformation of the actuator according to the needs, freely set the deformation position, realize a variety of deformation forms, and can realize local deformation regulation only at the required position.

[0016] 2. The liquid-gas phase change flexible actuator based on solid-liquid phase change control of the present invention utilizes the reversible solid-liquid phase change to control the energy storage-release process of liquid-gas phase change, thereby achieving rapid deformation. Compared with existing actuators based on liquid-gas phase change drive, it greatly accelerates the response speed (the deformation response time is as short as 67 ms in the experiment).

[0017] 3. The liquid-gas phase change flexible actuator based on solid-liquid phase change control of the present invention utilizes reversible solid-liquid phase change to lock the deformation generated by liquid-gas phase change. Compared with existing actuators based on liquid-gas phase change drive, it achieves deformation retention without power consumption (96% of the deformation angle can be maintained in the experiment), overcoming the problem of high energy consumption in deformation retention of liquid-gas phase change flexible drive. Attached Figure Description

[0018] Figure 1 This is a structural outline diagram of the liquid-gas phase change flexible actuator based on solid-liquid phase change regulation according to the present invention. Figure 2 This is an exploded view of the structure of the liquid-gas phase change flexible actuator based on solid-liquid phase change regulation of the present invention; Figure 3 This is a schematic diagram illustrating the deformation control principle of the liquid-gas phase change flexible actuator based on solid-liquid phase change regulation according to the present invention. Figure 4 This is a schematic diagram of the working process of the liquid-gas phase change flexible actuator based on solid-liquid phase change regulation in the regulation deformation mode of the present invention. Figure 5 This is a schematic diagram of the working process of the liquid-gas phase change flexible actuator based on solid-liquid phase change regulation in rapid deformation mode according to the present invention. Figure 6 This is a schematic diagram of the working process of the liquid-gas phase change flexible actuator based on solid-liquid phase change regulation in shape locking mode according to the present invention. Figure 7 This is a schematic diagram illustrating the cyclic deformation control of the liquid-gas phase change flexible actuator based on solid-liquid phase change regulation according to the present invention. Figure 8 The images show digital photographs and deformation simulation results of the liquid-gas phase change flexible actuator based on solid-liquid phase change control in this invention under (A) one-point deformation control and (B) two-point deformation control conditions. Figure 9The present invention is based on a liquid-gas phase change flexible actuator that adapts to the outer contours of objects of different shapes, such as (A) triangle, (B) square, (C) rectangle, and (D) circle, through deformation control.

[0019] In the figure: driving layer 1, first driving layer shell 11, liquid-gas phase change working medium 12, driving heating wire 13, second driving layer shell 14, fabric confinement layer 15, heat insulation layer 2, variable stiffness layer 3, first variable stiffness layer shell 31, stiffness adjustment heating wire 32, solid-liquid phase change working medium 33, second variable stiffness layer shell 34, fixing fixture 4. Detailed Implementation

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] like Figure 1 As shown, the liquid-gas phase change flexible actuator based on solid-liquid phase change control includes a driving layer 1, a heat insulation layer 2, and a variable stiffness layer 3, all of which are strip-shaped and arranged in close succession. Each pair of adjacent layers in the driving layer 1, heat insulation layer 2, and variable stiffness layer 3 is connected and fixed. Both the driving layer 1 and the variable stiffness layer 3 are equipped with electrically heated components. The driving layer 1 is driven to deform by the electrically heated components, and the variable stiffness layer 3 adjusts the stiffness of the deformation of the driving layer 1 at different positions by the electrically heated components. The driving layer 1 and the variable stiffness layer 3 work together to realize the deformation and adjustment of the liquid-gas phase change flexible actuator to any shape.

[0022] like Figure 2 As shown, the driving layer 1 mainly consists of a first driving layer shell 11, a liquid-gas phase change working medium 12, a driving heating wire 13, a second driving layer shell 14, and a sheet-like fabric restraint layer 15, all arranged in a tightly stacked manner and in strip shape. The second driving layer shell 14 is bonded to the fabric restraint layer 15, and the first driving layer shell 11 is arranged on top of the second driving layer shell 14. A relatively closed strip-shaped driving cavity is formed between the first driving layer shell 11 and the second driving layer shell 14. The driving heating wire 13 is arranged in the strip-shaped driving cavity and filled with the liquid-gas phase change working medium 12. The first driving layer shell 11 is configured as a toothed shell structure. The driving heating wire 13 extends and is arranged inside the strip-shaped driving shell and bends through each tooth of the toothed shell structure. The liquid-gas phase change working medium 12 fills the space inside the strip-shaped driving cavity except for the driving heating wire 13. The upper surface of the second driving layer shell 14 has a strip-shaped groove parallel to its own strip direction.

[0023] The strip-shaped groove on the upper surface of the second driving layer shell 14 is used to connect the various toothed cavities in the first driving layer shell 11, so that the liquid-gas phase change working medium 12 can flow freely therein. The fabric restricting layer 15 is used to restrict the elongation of the driving layer 1 in the length direction, and to ensure that the bending deformation that occurs is biased towards the fabric restricting layer 15.

[0024] The first driving layer shell 11 has hollow hole structures at both ends. The driving heating wire 13 passes through the hole structures at both ends of the first driving layer shell 11 and is connected to an external power source, and is used to heat the liquid-gas phase change working medium 12.

[0025] like Figure 3 As shown, the variable stiffness layer 3 includes a first variable stiffness layer shell 31, a stiffness-regulating heating wire 32, a solid-liquid phase change working fluid 33, and a second variable stiffness layer shell 34, all of which are strip-shaped. The top surface of the second variable stiffness layer shell 34 has a strip-shaped groove along the strip-shaped direction of the variable stiffness layer 3. The first variable stiffness layer shell 31 is connected to the groove opening of the second variable stiffness layer shell 34. A relatively closed strip-shaped variable stiffness cavity is formed between the first drive layer shell 11 and the second drive layer shell 14. The first drive layer shell 11 and the second drive layer shell 14 outside the strip-shaped variable stiffness cavity are fitted with stiffness-regulating heating wires 32. The strip-shaped variable stiffness cavity is filled with solid-liquid phase change working fluid 33.

[0026] The stiffness-regulating heating wire 32 consists of multiple annular heating wires that are equally spaced along the strip direction of the variable stiffness layer 3 and are independent of each other. Each annular heating wire is arranged around the outer periphery of the strip-shaped variable stiffness cavity in the circumferential direction. Each stiffness-regulating heating wire 32 is used to independently control the temperature of the solid-liquid phase change working medium 33. Each stiffness-regulating heating wire 32 passes through the outer shell of the variable stiffness layer 3 and is connected to an external power source.

[0027] By energizing and heating the stiffness-regulating heating wire 32 at a certain location, the solid-liquid phase change working medium 33 at the stiffness-regulating heating wire 32 undergoes a local solid-liquid phase change, thereby softening the position of the stiffness-regulating heating wire 32 in the variable stiffness layer 3. This is used to regulate the deformation stiffness of the liquid-gas phase change flexible actuator at each strip direction position when the drive layer 1 deforms.

[0028] The liquid-gas phase change flexible actuator also includes a fixing clamp 4, which is located on one side perpendicular to the strip direction of the drive layer 1 and is fixedly connected to the drive layer 1, the heat insulation layer 2 and the variable stiffness layer 3.

[0029] like Figure 3 As shown, after the driving heating wire 13 is energized and heated, the liquid-gas phase change working medium 12 in the driving strip cavity undergoes a liquid-gas phase change for driving, thereby driving the overall deformation of the liquid-gas phase change flexible actuator; the variable stiffness layer 3 uses the local solid-liquid phase change of the solid-liquid phase change working medium 33 to control the stiffness at various positions in the strip direction, thereby regulating the deformation stiffness of the liquid-gas phase change flexible actuator.

[0030] like Figure 2As shown, a column group is provided on both sides of the upper surface of the heat insulation layer 2 along its own strip direction. Each column group includes multiple columns. The columns of each column group are symmetrically distributed and extend along its own strip direction at equal intervals to form a column array structure. The heat insulation layer 2 is used to reduce the thermal interference between the driving layer 1 and the variable stiffness layer 3.

[0031] Solid-liquid phase change control method for liquid-gas phase change flexible actuators: Methods for determining the control actuator to achieve four different operating modes based on the following conditions: Deformation control mode: First, the variable stiffness layer 3 is energized and heated to regulate the deformation stiffness of the liquid-gas phase change flexible actuator at various positions along the strip direction. Then, the driving layer 1 is energized and heated to drive the overall deformation of the liquid-gas phase change flexible actuator, so as to achieve any expected deformation state.

[0032] Rapid Deformation Working Mode: First, the driving layer 1 is energized and heated to regulate the liquid-gas phase change flexible actuator for energy storage. Since the variable stiffness layer 3 is in a high stiffness state, the liquid-gas phase change flexible actuator does not bend or deform at this time. During this stage, the expansion of the driving layer 1 due to the liquid-gas phase change is converted into elastic potential energy and stored in the structure of the liquid-gas phase change flexible actuator. Then, the variable stiffness layer 3 is energized and heated. At this time, due to the local softening of the variable stiffness layer 3, the elastic potential energy stored in the actuator structure in the previous stage is suddenly released, which can quickly regulate the deformation stiffness of various positions in the strip direction of the liquid-gas phase change flexible actuator. The driving layer 1 deforms rapidly in the area softened by the energized and heated variable stiffness layer 3, so that the liquid-gas phase change flexible actuator deforms rapidly in the area softened by the energized and heated variable stiffness layer 3. The liquid-gas phase change flexible actuator achieves the rapid deformation working mode.

[0033] Shape-locking working mode: For a liquid-gas phase change flexible actuator that is in a deformed state, the temperature of the variable stiffness layer 3 is first cooled to solidify the variable stiffness layer 3, and then the drive layer 1 is cooled and liquefied, so that the shape protection of the liquid-gas phase change flexible actuator is locked, thereby realizing the shape-locking working mode.

[0034] Restoring the initial working mode: For a liquid-gas phase change flexible actuator that is in a deformed state, first cool the drive layer 1 to liquefy the drive layer 1 and restore its initial shape, then cool the temperature of the variable stiffness layer 3 to solidify the variable stiffness layer 3, thereby restoring the initial working mode.

[0035] More specifically, the deformation control working mode is as follows: by heating the stiffness control heating wire 32 of the stiffness control layer 3 at a certain position, the solid-liquid phase change working medium 33 at the position of the stiffness control heating wire 32 is further controlled to undergo solid-liquid phase change. Then, the driving heating wire 13 is heated to control the liquid-gas phase change working medium 12 of the driving layer 1 to undergo liquid-gas phase change as a whole, so that the liquid-gas phase change flexible actuator is deformed as a whole, and the liquid-gas phase change flexible actuator realizes the deformation control working mode.

[0036] More specifically, the rapid deformation working mode involves heating the driving heating wire 13 of the driving layer 1 to control the liquid-gas phase change working medium 12 to undergo a liquid-gas phase change, thereby regulating the driving layer 1 to enable the liquid-gas phase change flexible actuator to store energy. Since the variable stiffness layer 3 is in a high stiffness state, the actuator as a whole does not bend or deform. During this stage, the volume expansion of the driving layer 1 due to the liquid-gas phase change is converted into elastic potential energy and stored in the actuator structure. Then, heating the stiffness regulating heating wire 32 at a certain position further controls the solid-liquid phase change working medium 33 at the location of the stiffness regulating heating wire 32 to undergo a solid-liquid phase change, causing the variable stiffness layer 3 to soften at this location. The driving layer 1 rapidly deforms in the area softened by the electric heating of the variable stiffness layer 3, enabling the liquid-gas phase change flexible actuator to rapidly deform in the area softened by the electric heating of the variable stiffness layer 3. The liquid-gas phase change flexible actuator achieves the rapid deformation working mode.

[0037] The rapid deformation mode is achieved through an energy storage-release process, the specific process of which is as follows: In the first stage of energy storage, the drive layer 1 is energized and heated to store energy in the actuator. Since the variable stiffness layer 3 is in a high stiffness state, the liquid-gas phase change flexible actuator does not bend or deform. In this stage, the expansion of the drive layer 1 due to the liquid-gas phase change is converted into elastic potential energy and stored in the actuator structure. In the second stage of release, the variable stiffness layer 3 is energized and heated. At this time, due to the local softening of the variable stiffness layer 3, the elastic potential energy stored in the liquid-gas phase change flexible actuator structure in the previous stage is suddenly released, causing the liquid-gas phase change flexible actuator to bend and deform rapidly at the set position.

[0038] More specifically, for a liquid-gas phase change flexible actuator in a deformed state, while maintaining the liquid-gas phase change working medium 12 of the drive layer 1 in a vaporized drive state, the solid-liquid phase change working medium 33 of the variable stiffness layer 3 is cooled and solidified. Then, the liquid-gas phase change working medium 12 of the drive layer 1 is cooled and liquefied, so that the shape of the drive layer 1 is locked, resulting in the shape protection lock of the liquid-gas phase change flexible actuator, thereby realizing the shape locking working mode.

[0039] To restore the initial working mode, more specifically: for a liquid-gas phase change flexible actuator that is in a deformed state, while maintaining the solid-liquid phase change working medium 33 of the variable stiffness layer 3 in a liquefied driving state, the liquid-gas phase change working medium 12 of the liquefied driving layer 1 is cooled, so that the driving layer 1 returns to its initial shape. Then, the solid-liquid phase change working medium 33 of the variable stiffness layer 3 is cooled, so that the solid-liquid phase change working medium 33 solidifies, thereby realizing the restoration of the initial working mode.

[0040] The first driving layer shell 11 and the second driving layer shell 14 are made of low-hardness bicomponent silicone rubber, the first variable stiffness layer shell 31 and the second variable stiffness layer shell 34 are made of high-hardness bicomponent silicone rubber, and the heat insulation layer 2 is made of high-hardness bicomponent silicone rubber. The low-hardness bicomponent silicone rubber is a bicomponent silicone rubber with a Shore hardness between 0A and 5A, and the mixing mass ratio of components A and B in the low-hardness bicomponent silicone rubber is 1:1. The high-hardness bicomponent silicone rubber is a bicomponent silicone rubber with a Shore hardness between 10A and 50A, and the mixing mass ratio of components A and B in the high-hardness bicomponent silicone rubber is 1:1. The liquid-gas phase change working medium 12 is a fluid with a boiling point between 20℃ and 100℃, and the solid-liquid phase change working medium 33 is an alloy with a melting point between 30℃ and 150℃.

[0041] The actuator can employ different cooling methods, such as passive natural cooling, active air cooling, water cooling, or semiconductor cooling, depending on the required cooling rate. Due to the reversibility of liquid-gas phase change and solid-liquid phase change, the deformation and stiffness control of the actuator are reversible. In the controlled deformation working mode, the actuator can achieve repeated reversible controlled deformation and a wide variety of deformation forms. In the rapid deformation working mode, the actuator greatly accelerates the response speed of traditional liquid-gas phase change driving methods. In the shape-locking working mode, the actuator can maintain the deformed state without power consumption.

[0042] like Figure 7 As shown, the actuator can be repeatedly manipulated into different deformation forms, and can also return to its initial state and be manipulated into other deformation forms again, realizing reversible and diverse deformation control and local deformation control; such as Figure 8 As shown, the actuator demonstrates experimental results and deformation simulation effects under one-point and two-point deformation control conditions; due to the actuator's reversible and diverse deformation control capabilities and local deformation control capabilities, such as... Figure 9 As shown, through multiple reversible deformation adjustments, the same actuator can adapt to the outer contours of objects with different shapes such as triangles, squares, rectangles, and circles.

[0043] like Figure 4 As shown, in the controlled deformation working mode, the actuator can achieve repeated reversible controlled deformation and a wide variety of deformation forms; such as Figure 5 As shown, in the rapid deformation working mode, the actuator significantly accelerates the response speed of the traditional liquid-gas phase change drive method; such as Figure 6 As shown, in shape-locked operating mode, the actuator can maintain the deformed state without consuming power.

[0044] By controlling the sequence of the two phase transitions, the actuator can achieve various operating modes, including controlled deformation, rapid deformation, and shape locking. The liquid-gas phase change flexible actuator based on solid-liquid phase change control of this invention enables repeated and reversible controlled deformation of the actuator, possessing advantages such as diverse deformation forms, fast response speed, and low energy consumption in maintaining deformation, and has significant application prospects.

[0045] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A liquid-gas phase change flexible actuator based on solid-liquid phase change regulation, characterized in that: It includes a driving layer (1), a heat insulation layer (2), and a variable stiffness layer (3) that are all strip-shaped and arranged in close succession. Each pair of adjacent layers in the driving layer (1), heat insulation layer (2), and variable stiffness layer (3) are connected and fixed. The driving layer (1) and the variable stiffness layer (3) are both equipped with electrically heated components. The driving layer (1) is driven to deform by the electrically heated components, and the variable stiffness layer (3) adjusts the stiffness of the driving layer (1) at different positions by the electrically heated components. The driving layer (1) and the variable stiffness layer (3) work together to realize the deformation and adjustment of the liquid-gas phase change flexible actuator in any shape. The variable stiffness layer (3) includes a first variable stiffness layer shell (31) that is strip-shaped, a stiffness-regulating heating wire (32), a solid-liquid phase change working medium (33), and a second variable stiffness layer shell (34). The top surface of the second variable stiffness layer shell (34) is provided with a strip-shaped groove along the strip-shaped direction of the variable stiffness layer (3). The first variable stiffness layer shell (31) is connected to the groove opening of the second variable stiffness layer shell (34). A relatively closed strip-shaped variable stiffness cavity is formed between the first variable stiffness layer shell (31) and the second variable stiffness layer shell (34). The first variable stiffness layer shell (31) and the second variable stiffness layer shell (34) outside the strip-shaped variable stiffness cavity are fitted with stiffness-regulating heating wires (32). The strip-shaped variable stiffness cavity is filled with solid-liquid phase change working medium (33). The stiffness-regulating heating wire (32) consists of multiple annular heating wires arranged at intervals along the strip direction of the variable stiffness layer (3) and each annular heating wire is arranged around the outer periphery of the strip variable stiffness cavity in the circumferential direction. Each stiffness-regulating heating wire (32) is used to independently control the temperature of the solid-liquid phase change working medium (33), and each of the stiffness-regulating heating wires (32) passes through the outer shell of the variable stiffness layer (3) and is connected to an external power source.

2. The liquid-gas phase change flexible actuator based on solid-liquid phase change regulation according to claim 1, characterized in that: The driving layer (1) mainly consists of a first driving layer shell (11), a liquid-gas phase change working fluid (12), a driving heating wire (13), a second driving layer shell (14), and a sheet-like fabric restraint layer (15), all arranged in close succession and in strip shape. The second driving layer shell (14) is bonded to the fabric restraint layer (15), and the first driving layer shell (11) is arranged on top of the second driving layer shell (14). The first driving layer shell (11) and the second driving layer shell (14) form a relatively closed interior. The strip-shaped drive cavity is provided with a drive heating wire (13) and filled with a liquid-gas phase change working medium (12); the first drive layer shell (11) is configured as a toothed shell structure, the drive heating wire (13) extends and is arranged inside the strip-shaped drive shell and bends through each tooth of the toothed shell structure, and the liquid-gas phase change working medium (12) fills the space inside the strip-shaped drive cavity except for the drive heating wire (13); the upper surface of the second drive layer shell (14) is provided with a strip-shaped groove parallel to its own strip-shaped direction.

3. The liquid-gas phase change flexible actuator based on solid-liquid phase change regulation according to claim 2, characterized in that: The first driving layer shell (11) has hollow hole structures at both ends. The driving heating wire (13) passes through the hole structures at both ends of the first driving layer shell (11) and is connected to an external power source, and is used to heat the liquid-gas phase change working medium (12).

4. The liquid-gas phase change flexible actuator based on solid-liquid phase change regulation according to claim 1, characterized in that: By energizing and heating the stiffness-regulating heating wire (32) at a certain position, the solid-liquid phase change working medium (33) at the stiffness-regulating heating wire (32) undergoes a local solid-liquid phase change, thereby softening the position at the stiffness-regulating heating wire (32) of the variable stiffness layer (3), which is used to regulate the deformation stiffness of the liquid-gas phase change flexible actuator at each strip direction position when the drive layer (1) deforms.

5. The liquid-gas phase change flexible actuator based on solid-liquid phase change regulation according to claim 2, characterized in that: After the driving heating wire (13) is energized and heated, it drives the liquid-gas phase change working medium (12) in the strip-shaped driving cavity to undergo liquid-gas phase change for driving, thereby driving the overall deformation of the liquid-gas phase change flexible actuator; the variable stiffness layer (3) uses the local solid-liquid phase change of the solid-liquid phase change working medium (33) to control the stiffness at various positions in the strip direction, thereby regulating the deformation stiffness of the liquid-gas phase change flexible actuator.

6. The liquid-gas phase change flexible actuator based on solid-liquid phase change regulation according to claim 1, characterized in that: The upper surface of the heat insulation layer (2) is provided with a column group on each side along its strip direction. Each column group includes multiple columns. The columns in each column group are symmetrically distributed and extend along its strip direction at equal intervals to form a column array structure. The heat insulation layer (2) is used to reduce the thermal interference between the driving layer (1) and the variable stiffness layer (3).

7. A method for controlling the solid-liquid phase change of a liquid-gas phase change flexible actuator according to any one of claims 1-6, characterized in that: Methods for controlling actuators to achieve four different operating modes: Adjusting the deformation working mode: First, the variable stiffness layer (3) is heated by electricity to adjust the deformation stiffness of each position in the strip direction of the liquid-gas phase change flexible actuator. Then, the driving layer (1) is heated by electricity to drive the overall deformation of the liquid-gas phase change flexible actuator, so as to achieve any expected deformation state. Rapid deformation working mode: First, the driving layer (1) is energized and heated to regulate the liquid-gas phase change flexible actuator to store energy. Then, the variable stiffness layer (3) is energized and heated to regulate the deformation stiffness of the liquid-gas phase change flexible actuator at various positions in the strip direction. The driving layer (1) rapidly deforms in the area softened by the energized and heated variable stiffness layer (3), so that the liquid-gas phase change flexible actuator rapidly deforms in the area softened by the energized and heated variable stiffness layer (3), and the liquid-gas phase change flexible actuator achieves rapid deformation working mode. Shape locking working mode: For a liquid-gas phase change flexible actuator in a deformed state, first cool the temperature of the variable stiffness layer (3) to solidify the variable stiffness layer (3), and then cool and liquefy the drive layer (1) to lock the shape protection of the liquid-gas phase change flexible actuator, thereby realizing the shape locking working mode. Restoring the initial working mode: For the liquid-gas phase change flexible actuator that is in a deformed state, first cool the drive layer (1) to make the drive layer (1) liquefy and restore the initial shape, and then cool the temperature of the variable stiffness layer (3) to make the variable stiffness layer (3) solidify, thereby realizing the restoration of the initial working mode.

8. The solid-liquid phase change control method for the liquid-gas phase change flexible actuator according to claim 7, characterized in that: More specifically, the controlled deformation working mode is as follows: by heating the stiffness control heating wire (32) of the variable stiffness layer (3) at a certain position, the solid-liquid phase change working medium (33) at the position of the stiffness control heating wire (32) is further controlled to undergo solid-liquid phase change, and then the driving heating wire (13) is heated to control the liquid-gas phase change working medium (12) of the driving layer (1) to undergo liquid-gas phase change as a whole, so that the liquid-gas phase change flexible actuator is deformed as a whole, and the liquid-gas phase change flexible actuator realizes the controlled deformation working mode; More specifically, the rapid deformation working mode is as follows: by heating the driving heating wire (13) of the driving layer (1) to control the liquid-gas phase change working medium (12) to undergo liquid-gas phase change, thereby regulating the driving layer (1) to enable the liquid-gas phase change flexible actuator to store energy, and then heating the stiffness regulating heating wire (32) at a certain position to further control the solid-liquid phase change working medium (33) at the position of the stiffness regulating heating wire (32) to undergo solid-liquid phase change, so that the variable stiffness layer (3) softens at this position, and the driving layer (1) rapidly deforms in the area softened by the electric heating of the variable stiffness layer (3), so that the liquid-gas phase change flexible actuator rapidly deforms in the area softened by the electric heating of the variable stiffness layer (3), and the liquid-gas phase change flexible actuator realizes the rapid deformation working mode; More specifically, the shape locking working mode is as follows: for a liquid-gas phase change flexible actuator in a deformed state, while maintaining the liquid-gas phase change working medium (12) of the driving layer (1) in a vaporization driving state, the solid-liquid phase change working medium (33) of the variable stiffness layer (3) is cooled and solidified, and then the liquid-gas phase change working medium (12) of the driving layer (1) is cooled and liquefied, so that the shape locking of the driving layer (1) causes the shape protection locking of the liquid-gas phase change flexible actuator, thereby realizing the shape locking working mode; More specifically, the restoration of the initial working mode is as follows: for a liquid-gas phase change flexible actuator in a deformed state, while maintaining the solid-liquid phase change working medium (33) of the variable stiffness layer (3) in a liquefied driving state, the liquid-gas phase change working medium (12) of the driving layer (1) is cooled and liquefied, so that the driving layer (1) restores its initial shape. Then, the solid-liquid phase change working medium (33) of the variable stiffness layer (3) is cooled and the solid-liquid phase change working medium (33) is solidified, thereby realizing the restoration of the initial working mode.

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