A soft actuator with variable curvature mimicking a tendril

Abstract

The application discloses a soft actuator with variable curvature, which is composed of an executing mechanism and a control mechanism. The executing mechanism is composed of a large-strain layer, a limiting layer and a base. The large-strain layer is a strip-shaped silica gel body formed by sequentially connecting a first-end air module, a plurality of middle air modules and a tail-end air module arranged in a line. Each air module is provided with an air chamber, and the air chambers are communicated with each other and penetrate through the front end face of the first-end air module. The limiting layer is composed of a lower adhesive layer, a small-strain layer and an upper adhesive layer arranged from bottom to top, and is fixed on the bottom surface of the large-strain layer. The base is provided with a plate body with a third communication air channel. The first-end air module is fixed on the base and makes the third communication air channel communicated with the air chambers. The control mechanism is connected with an external air source and the base of the executing mechanism. The actuator can form a variable curvature Euler spiral shape, effectively grasp objects with different sizes, and has the advantages of simple structure, simple manufacturing, low cost and the like.

Description

Technical Field

[0001] This invention relates to the field of soft robot technology, and in particular to a tendril-like variable curvature soft actuator. Background Technology

[0002] With the rapid development of bionics and materials science, various bionic robots designed and manufactured using soft materials have emerged. Their flexible body structures endow bionic robots with greater freedom of movement, safer human-machine interaction, and simpler control systems, achieving impressive results in fields such as rescue, medical care, and services.

[0003] The design of soft robots benefits from the ingenious and effective solutions that natural systems provide for complex problems; for example, the spiral-growing tendrils of plants can firmly grasp supports of different sizes, demonstrating their structural superiority. Based on this, elastic actuators, as an important component of soft robots, were first introduced into soft robot design by Correll N, A, Onal D, et al., who introduced rib-like structures. However, their structure limited the bending performance of elastic actuators (see Correll N, A, Onal D, et al. Soft Autonomous Materials—Using Active Elasticity and Embedded Distributed Computation[J]. Springer Tracts in Advanced Robotics,2010,79.). Meanwhile, Mosadegh B, Polygerinos P, Keplinger C, et al. (see Mosadegh B, Polygerinos P, Keplinger C, et al. Pneumatic Networks for Soft Robotics that Actuate Rapidly[J]. Advanced Functional Materials, 2014,24(15):2163-2170.) proposed an elastic actuator with a rapid pneumatic network structure, which improved the bending performance of elastic actuators. However, in the elastic actuators of the aforementioned soft robots, the design of equal wall thickness causes the elastic actuators to form a shape with equal curvature after deformation, thereby limiting the size of the objects that the elastic actuators can grasp. Summary of the Invention

[0004] The purpose of this invention is to provide a tendril-like variable curvature soft actuator that can overcome the limitation of elastic actuators on the size of objects they can grasp.

[0005] Therefore, the technical solution of the present invention is as follows:

[0006] A tendril-like variable curvature soft actuator consists of an actuator and a control mechanism; the actuator consists of a large strain layer, a confinement layer and a base.

[0007] The large strain layer is a strip-shaped silicone body formed by sequentially connecting a first-end ventilation module, multiple intermediate ventilation modules, and a tail-end ventilation module arranged in a straight line at equal intervals. Each ventilation module is sequentially connected and integrally formed by connecting lugs extending outward from the bottom of its outer wall along the length of the large strain layer. From bottom to top, each ventilation module has a connected ventilation groove and an air chamber. The ventilation groove is a through groove that extends along the length of the large strain layer and extends to the outer end face of the connecting lug. The ventilation grooves of each ventilation module are sequentially connected to form a first connecting air channel. The air chamber is a cubic cavity with an opening at the bottom. The air chambers of each ventilation module are interconnected through the first connecting air channel. From the inner wall of the air chamber of the first-end ventilation module, a second connecting air channel extends along the length of the large strain layer to its front end face.

[0008] The limiting layer is composed of a lower adhesive layer, a small strain layer and an upper adhesive layer arranged sequentially from bottom to top. It has the same bottom surface size as the large strain layer and is fixed to the bottom surface of the large strain layer to seal the bottom opening of the first connecting air passage. The lower adhesive layer and the upper adhesive layer are silicone plates, and the small strain layer is a strip plate with the function of limiting tension and bending.

[0009] The base is a plate with a third connecting air passage in the center; the front end of the ventilation module is fixed to one side of the base, and the second connecting air passage is connected to the third connecting air passage.

[0010] The control mechanism is connected to the base of the external air source and the actuator respectively, so as to control the external air source to input high-pressure gas into the third connecting air channel or to output high-pressure gas from the third connecting air channel.

[0011] Furthermore, along the length of the large strain layer, the rear wall thickness of the front ventilation module in every two adjacent intermediate ventilation modules is the same as the front wall thickness of the rear ventilation module, and the front wall thickness of the same intermediate ventilation module is greater than the rear wall thickness, so that the width of the air chamber of each intermediate ventilation module gradually increases from front to back along the length of the large strain layer.

[0012] Furthermore, each intermediate ventilation module has the same width along the length of the large strain layer, with a value ranging from 8mm to 10mm; the front wall thickness of the intermediate ventilation module at the first end is 3mm, and the difference between the front and rear wall thicknesses of the same intermediate ventilation module is 1mm; the spacing between adjacent ventilation modules is 2mm.

[0013] Furthermore, the ventilation slots of each ventilation module are located at the center of the bottom surface of the module; the cubic chambers of each intermediate ventilation module are all formed by opening upwards from the center of the bottom surface of the module.

[0014] Furthermore, along the length of the large strain layer, the width of the air chamber of the first-end ventilation module is greater than the width of the air chamber of the middle ventilation module located at the first end.

[0015] Furthermore, the high-strain layer, the upper adhesive layer, and the lower adhesive layer are all made of silicone with a hardness of 0.5HA to 2HA.

[0016] Furthermore, the upper and lower adhesive layers are strips with a thickness of 1.8mm to 2mm.

[0017] Furthermore, the low-strain layer is made of materials with an elastic modulus of 6400 MPa to 6500 MPa, a Poisson's ratio of 0.2 to 0.22, and a density of 750 kg / mm³. 3 ~800kg / mm 3 Strips made of materials with a thickness of 0.1mm to 0.2mm.

[0018] Furthermore, the upper adhesive layer and the lower adhesive layer have the same length and width, and the length and width of the small strain layer are 2mm~3mm smaller than the length and width of the lower adhesive layer, so that the small strain layer is sandwiched between the upper adhesive layer and the lower adhesive layer and is sealed to the outside.

[0019] Furthermore, the base consists of a fixed plate and an inverted U-shaped connector; the fixed plate is a cubic plate with an annular groove at the center of each of its two side surfaces, and a third connecting air passage is axially formed at the center of a cylindrical body located at the center of the annular groove; a U-shaped frame extends outward from the center of one side surface of the fixed plate, the vertical plate of the U-shaped frame is parallel to the surface of the fixed plate, and a through hole is formed from the center of the outer vertical plate to the groove of the adjacent side surface; the inverted U-shaped connector consists of connecting screws and a front fixing... The front and rear fixing blocks are composed of a front fixing block and a rear fixing block. The front fixing block and the rear fixing block are two parts formed by splitting an inverted U-shaped body. The two parts are detachably fixed together by connecting screws. The size of the inverted U-shaped body is adapted to the size of the U-shaped frame and the through slot opened on the top surface of the front end of the first end ventilation module, which is perpendicular to the length direction of the large strain layer. This allows it to be built into the U-shaped frame and clamped on both sides of the first end ventilation module that is inserted into the U-shaped frame through the through hole. The top of the inverted U-shaped connector is built into the through slot opened on the top surface of the first end ventilation module.

[0020] Furthermore, the control mechanism includes a first solenoid valve, a second solenoid valve, a PLC controller, a three-way connector, an air inlet line, an air delivery line, and an air vent line; wherein, one end of the air inlet line is connected to the first interface of the three-way connector to form a connection, and the other end is connected to an external air source; one end of the air delivery line is connected to the second interface of the three-way connector to form a connection, and the other end is connected to the other end of a third connecting air passage; one end of the air vent line is connected to the third interface of the three-way connector to form a connection; the first solenoid valve is installed on the air inlet line to control the opening / closing of the air inlet line; the second solenoid valve is installed on the air vent line to control the opening / closing of the air vent line; the PLC controller is electrically connected to the first solenoid valve and the second solenoid valve respectively to control the opening / closing of the first solenoid valve and the second solenoid valve.

[0021] Compared with existing technologies, this tendril-like variable curvature soft actuator consists of an actuator mechanism and a control mechanism. The actuator mechanism is an elastic and bendable structure composed of a large strain layer and a confinement layer with multiple elastic air chambers of varying sizes. The control mechanism controls the gas pressure entering the elastic air chambers, enabling the actuator mechanism to form a variable curvature Euler spiral shape during operation, thus achieving effective grasping of objects of different sizes. In addition, the actuator mechanism utilizes a combination of 3D printing and casting technology, featuring a simple structure, easy manufacturing, and low cost without the need for expensive materials, making it a promising candidate for application. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the undeformed structure of the simulated tendril variable curvature soft actuator of the present invention.

[0023] Figure 2 This is a schematic diagram of the structure of the simulated tendril variable curvature soft actuator of the present invention in a deformed state;

[0024] Figure 3 This is a schematic diagram of the large strain layer and the confinement layer of the simulated tendril variable curvature soft actuator of the present invention;

[0025] Figure 4 This is a schematic diagram of the front and rear fixing blocks of the simulated tendril variable curvature soft actuator of the present invention assembled with screws.

[0026] Figure 5 for Figure 2 AA section view;

[0027] Figure 6 for Figure 2 BB cross-sectional view;

[0028] Figure 7 for Figure 3 CC section view;

[0029] Figure 8 for Figure 3 DD sectional view;

[0030] Figure 9 This is a schematic diagram of the control system of the simulated tendril variable curvature soft actuator of the present invention.

[0031] Figure 10 This is a schematic diagram of the structure of the simulated tendril variable curvature soft actuator of the present invention, in which compressed gas with a pressure of 0-11 kPa is gradually applied inside, and the large strain layer undergoes different curvature deformations. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the following embodiments are by no means intended to limit the present invention.

[0033] See Figure 1 and Figure 2 The simulated tendril variable curvature soft actuator includes an actuator and a control mechanism; wherein the actuator is composed of a large strain layer 1, a confinement layer 2 and a base 3.

[0034] See Figure 3 and Figure 8 The large strain layer 1 is a strip-shaped silicone body formed by sequentially connecting one first-end ventilation module, 19 intermediate ventilation modules, and one last-end ventilation module arranged in a straight line at equal intervals. The first-end ventilation module is a strip-shaped cube with a through mounting groove on its front top surface that runs through the width direction, and a connecting ear plate that extends outward along the length direction of the large strain layer at the bottom of its rear end face. A first ventilation groove and a first air chamber are sequentially formed from bottom to top on the rear bottom surface of the first-end ventilation module. The first ventilation groove is a through groove that runs along the length direction of the large strain layer, with one end extending to the outer end face of the connecting ear plate and the other end communicating with the first air chamber, and it is centrally located on the bottom surface of the first-end ventilation module. The first air chamber is a cubic chamber, and a second connecting air channel that runs forward along the length direction of the large strain layer from the inner wall of the first air chamber to the front end face of the first-end ventilation module.

[0035] The intermediate ventilation module is a cubic block with symmetrically arranged connecting lugs extending from the bottom of its front end face and the bottom of its rear end face along the length of the large strain layer. A second ventilation groove 15 and a second air chamber 14 are sequentially formed from bottom to top on the bottom surface of the intermediate ventilation module. The second ventilation groove 15 is a through groove that extends along the length of the large strain layer and passes through the outer end faces of the two connecting lugs, and it is centrally located on the bottom surface of the intermediate ventilation module. The second air chamber 14 is a cubic cavity that communicates with the second ventilation groove 15.

[0036] The tail-end ventilation module is a cubic block. Its front end face extends outward along the length of the large strain layer and forms a connecting ear plate. A third ventilation groove and a third air chamber are sequentially formed from bottom to top on the bottom surface of the tail-end ventilation module. The third ventilation groove is a through groove that extends along the length of the large strain layer, with one end penetrating to the outer end face of the connecting ear plate and the other end communicating with the third air chamber. The third air chamber is also a cubic cavity.

[0037] In the large strain layer 1, adjacent first-end ventilation modules and intermediate ventilation modules, two adjacent intermediate ventilation modules, and adjacent intermediate ventilation modules and tail-end ventilation modules are connected by adjacent connecting lugs and integrally formed. The first ventilation groove of the first-end ventilation module, the second ventilation groove 15 of each intermediate ventilation module, and the third ventilation groove of the tail-end ventilation module are sequentially connected to form a first connecting air passage, so that the air chamber of each ventilation module and the second connecting air passage are respectively connected to the first connecting air passage. At the same time, along the length direction of the large strain layer 1, the rear wall thickness of the front ventilation module in each pair of adjacent intermediate ventilation modules is the same as the front wall thickness of the rear ventilation module, and the front wall thickness of the same intermediate ventilation module is greater than the rear wall thickness, so that the width of the air chamber of each intermediate ventilation module gradually increases from front to back along the length direction of the large strain layer 1.

[0038] See Figure 7 In this embodiment, the large strain layer 1 has a length of 224 mm, a width of 20 mm, and a thickness of 16 mm. The large strain layer 1 consists of a front-end ventilation module, 19 intermediate ventilation modules, and a rear-end ventilation module. The front-end ventilation module has a length of 22 mm, a width of 20 mm, and a thickness of 16 mm; the rear-end ventilation module has a length of 10 mm, a width of 20 mm, and a thickness of 16 mm; the intermediate ventilation modules all have a length of 8 mm, a width of 20 mm, and a thickness of 16 mm; all connecting lugs have the same dimensions, making the phase... The gaps between adjacent connecting blocks are the same, all being 2mm; the width of the first air chamber of the first end ventilation module along the length of the large strain layer is 3mm, and the width of the third air chamber of the tail end ventilation module along the length of the large strain layer is 4mm; based on the number of intermediate ventilation modules being 19, the front wall thickness of each intermediate ventilation module along the length of the large strain layer decreases by 1mm, that is, gradually decreases from 3mm to 1.1mm, and correspondingly, the width of the air chamber of each intermediate ventilation module along the length of the large strain layer increases by 2mm, that is, gradually increases from 2.1mm to 5.7mm.

[0039] See Figure 3 The limiting layer 2 is composed of a lower adhesive layer 7, a small strain layer 6, and an upper adhesive layer 5 arranged sequentially from bottom to top; specifically,

[0040] The lower adhesive layer 7 is a strip of silicone sheet, specifically a sheet made of silicone with a hardness of 0.5HA; the length and width of the lower adhesive layer 7 are the same as the bottom length and width of the large strain layer 1, which are 224mm×20mm; the thickness of the lower adhesive layer 7 is 2mm.

[0041] The small strain layer 6 is a flexible strip plate that restricts tension; the length and width of the small strain layer 6 are slightly smaller than the length and width of the bottom surface of the large strain layer 1, specifically 222mm × 18mm; the thickness of the small strain layer 6 is 0.1mm; in terms of material selection, the small strain layer 6 uses an elastic modulus of 6500MPa, a Poisson's ratio of 0.2, and a density of 750kg / mm³. 3 The material; in this embodiment, the small strain layer 6 is a paper layer with a thickness of 0.1 mm;

[0042] The upper adhesive layer 5 is a strip of silicone plate, specifically a plate made of silicone with a hardness of 0.5HA; specifically, the length and width of the upper adhesive layer 5 are the same as the bottom length and width of the large strain layer 1, which are 224mm×20mm; the thickness of the upper adhesive layer 5 is 2mm.

[0043] Liquid silicone is used to bond the bottom surface of the large strain layer 1 to the top surface of the upper adhesive layer 5, the bottom surface of the upper adhesive layer 5 to the top surface of the small strain layer 6, and the bottom surface of the small strain layer 6 to the top surface of the lower adhesive layer 7. This allows the small strain layer 6 to be sandwiched between the upper adhesive layer 5 and the lower adhesive layer 7. At the same time, the large strain layer 1 and the limiting layer 2 are connected and fixed together to form a deformation actuator.

[0044] In this embodiment, the specific preparation steps of the deformable actuator are as follows: S1, using resin material, 3D printing to prepare a mold; S2, cleaning the mold and uniformly applying Vaseline inside the mold; S3, using casting molding to prepare a large strain layer, an upper adhesive layer, and a lower adhesive layer; S4, cutting a small middle strain layer slightly smaller than the upper adhesive layer; S5, using uncured liquid silicone, sequentially bonding and sealing the large strain layer, the upper adhesive layer, the small middle strain layer, and the lower adhesive layer.

[0045] See Figure 1 The base 3 consists of a fixed plate and an inverted U-shaped connector; among which,

[0046] See Figure 5 The fixing plate is a cubic plate with annular grooves at the center of both sides. A third connecting air passage 11 is axially formed at the center of a cylindrical body located at the center of the annular grooves. A U-shaped frame extends outward from the center of one side of the fixing plate, with its vertical plate parallel to the surface of the fixing plate. A through hole extending through to the groove on the adjacent side plate is formed at the center of the outer vertical plate. (See also...) Figure 6A circular through hole 13a is provided at each of the four top corners of the fixed plate, and a strip through hole 13b is provided at each of the four edges of the fixed plate. The circular through hole 13a and the strip through hole 13b are used to connect the tendril-like variable curvature soft actuator to the arm of the external robot.

[0047] See Figure 4 The inverted U-shaped connector consists of a connecting screw 8, a front fixing block 9, and a rear fixing block 10; wherein the front fixing block 9 and the rear fixing block 10 are two parts formed by splitting an inverted U-shaped body, and the two are detachably fixed together by the connecting screw 8.

[0048] In use, the execution base is vertically positioned next to the first-end ventilation module with its fixing plate, and the front end of the first-end ventilation module is inserted into the U-shaped frame through the through hole, keeping the opening of the U-shaped frame facing upwards; the front fixing block 9 and the rear fixing block 10 of the inverted U-shaped connector are respectively clamped on both sides of the first-end ventilation module from both sides of the U-shaped frame, and after their tops are embedded into the mounting groove opened on the front top surface of the first-end ventilation module and aligned, they are connected and fixed together by the connecting screws 8, thereby connecting and fixing the first-end ventilation module and the execution base together; at this time, the third connecting air passage 11 is connected to the second connecting air passage and forms a connection;

[0049] See Figure 6 The control system is built into the central cavity of the base and includes a first solenoid valve 16, a second solenoid valve 17, a PLC controller 18, a Y-type three-way connector 19, an air inlet line, an air delivery line, and an air vent line. One end of the air inlet line is connected to the first interface (L1 end) of the three-way connector 19, and the other end is connected to an external air source. One end of the air delivery line is connected to the second interface (L2 end) of the three-way connector 19, and the other end is connected to the other end of the third connecting air passage 11. One end of the air vent line is connected to the third interface (L3 end) of the three-way connector 19. The first solenoid valve 16 is located on the air inlet line to control its opening and closing. The second solenoid valve 17 is located on the air vent line to control its opening and closing. The PLC controller 18 is electrically connected to both the first solenoid valve 16 and the second solenoid valve 17 to control them.

[0050] In use, the operating principle of this actuator control system is as follows: the control system controls the internal pressure of the actuator. The control system includes a first solenoid valve 16, a second solenoid valve 17, a PLC controller 18, and a Y-type three-way air pipe connector 19. The PLC controller 18 controls the opening and closing of the solenoid valves. The air source is connected to the first solenoid valve 16 through an air pipe. The first solenoid valve 16 is connected to port L1 of the air pipe connector 19. Port L2 is connected to the gas pipe 11 of the actuator base, and port L3 is connected to the second solenoid valve 17. When the first solenoid valve 16 is open and the second solenoid valve 17 is closed, gas flows into the elastic actuator, and the elastic actuator bends in an Euler spiral shape. When the second solenoid valve 17 is open, the elastic actuator returns to its initial shape.

[0051] Furthermore, to demonstrate that the simulated tendril variable curvature software actuator can achieve simulated tendril variable curvature motion, the finite element analysis method was used to simulate the actuator's motion.

[0052] like Figure 10 The diagram illustrates the structure of a tendril-like variable curvature soft actuator, where compressed gas pressures ranging from 0 to 11 kPa are gradually applied inside, causing the large strain layer to undergo different curvature deformations. As can be seen from the diagram, in the initial state, the actuator's mechanism is a strip-shaped body. When the control mechanism gradually introduces an external air source (compressed air) into the actuator's gas channel, the internal pressure gradually increases, reaching 8 kPa, 9 kPa, 10 kPa, and 11 kPa respectively. At this point, the actuator begins to bend, with the degree of bending gradually increasing, mimicking the Euler spiral shape of a tendril. Simultaneously, as the internal pressure increases, the opening size between the two ends of the bent actuator gradually decreases, as does the inner diameter, thus meeting the grasping requirements for objects of different sizes. Furthermore, due to the wide range of curvature variations in this actuator, it is particularly suitable for grasping small objects.

Claims

1. A tendril-like variable curvature soft actuator, characterized in that, It consists of an actuator and a control mechanism; the actuator consists of a large strain layer (1), a confinement layer (2) and a base (3); The large strain layer (1) is a strip-shaped silicone body formed by sequentially connecting a head ventilation module, multiple intermediate ventilation modules, and a tail ventilation module arranged in a straight line at equal intervals; the ventilation modules are sequentially connected and integrally formed by connecting ear plates extending outward from the bottom of their outer walls along the length direction of the large strain layer (1), and connected ventilation grooves and air chambers are sequentially opened from bottom to top on the bottom surface of each ventilation module; the ventilation groove is a through groove opened along the length direction of the large strain layer (1) and extending to the outer end face of the connecting ear plate, and the ventilation grooves of each ventilation module are sequentially connected to form the first connecting air passage; the air chamber is a cubic chamber with an opening at the bottom, and the ventilation modules of each ventilation module are connected to form the first connecting air passage. The air chambers are interconnected through the first connecting air passage; a second connecting air passage is opened from the inner wall of the air chamber of the first end ventilation module along the length direction of the large strain layer (1) to its front end face; along the length direction of the large strain layer (1), the rear wall thickness of the front ventilation module in each of two adjacent intermediate ventilation modules is the same as the front wall thickness of the rear ventilation module, and the front wall thickness of the same intermediate ventilation module is greater than the rear wall thickness, so that the width of the air chamber of each intermediate ventilation module gradually increases from front to back along the length direction of the large strain layer (1); the width of each intermediate ventilation module is the same along the length direction of the large strain layer (1); the cubic chamber of each intermediate ventilation module is opened from the center of the bottom surface of the module upward. The limiting layer (2) is composed of a lower adhesive layer (7), a small strain layer (6) and an upper adhesive layer (5) arranged sequentially from bottom to top. It has the same bottom surface size as the large strain layer (1) and is fixed on the bottom surface of the large strain layer (1) to seal the bottom opening of the first connecting airway. The lower adhesive layer (7) and the upper adhesive layer (5) are silicone plates, and the small strain layer (6) is a strip plate with the function of limiting tension and bending. The base (3) is a plate with a third connecting air passage (11) in the center; the front end of the first end ventilation module is fixed to one side of the base (3) and connects the second connecting air passage with the third connecting air passage (11); The control mechanism is connected to the base (3) of the external gas source and the actuator respectively, so as to control the external gas source to input high-pressure gas into the third connecting gas channel (11) or to output high-pressure gas from the third connecting gas channel (11).

2. The simulated tendril variable curvature soft actuator according to claim 1, characterized in that, The thickness of each intermediate ventilation module is 8mm to 10mm; the front wall thickness of the intermediate ventilation module at the beginning is 3mm, and the difference between the front and rear wall thicknesses of the same intermediate ventilation module is 1mm; the spacing between adjacent ventilation modules is 2mm.

3. The simulated tendril variable curvature soft actuator according to claim 1, characterized in that, The ventilation slots of each ventilation module are located at the center of the bottom surface of the module; the cubic chambers of each intermediate ventilation module are formed by opening upwards from the center of the bottom surface of the module.

4. The simulated tendril variable curvature soft actuator according to claim 1, characterized in that, The large strain layer (1), the upper adhesive layer (5) and the lower adhesive layer (7) are all made of silicone with a hardness of 0.5HA~2HA.

5. The simulated tendril variable curvature soft actuator according to claim 1, characterized in that, The upper adhesive layer (5) and the lower adhesive layer (7) are strips with a thickness of 1.8 mm to 2 mm.

6. The simulated tendril variable curvature soft actuator according to claim 1, characterized in that, The low-strain layer (6) is made of materials with an elastic modulus of 6400 MPa to 6500 MPa, a Poisson's ratio of 0.2 to 0.22, and a density of 750 kg / mm³. 3 ~800kg / mm 3 Strips made of materials with a thickness of 0.1mm to 0.2mm.

7. The simulated tendril variable curvature soft actuator according to claim 1, characterized in that, The upper adhesive layer (5) and the lower adhesive layer (7) have the same length and width. The length and width of the small strain layer (6) are 2mm~3mm smaller than the length and width of the lower adhesive layer (7), so that the small strain layer (6) is sandwiched between the upper adhesive layer (5) and the lower adhesive layer (7) and is sealed to the outside.

8. The simulated tendril variable curvature soft actuator according to claim 1, characterized in that, The base (3) consists of a fixed plate and an inverted U-shaped connector; wherein, the fixed plate is a cubic plate, and an annular groove is provided at the center of both sides of the plate, and a third connecting air passage (11) is provided axially at the center of the cylindrical body located at the center of the annular groove; a U-shaped frame extends outward from the center of one side of the fixed plate and forms a U-shaped frame, the vertical plate of the U-shaped frame is parallel to the plate surface of the fixed plate, and a through hole is provided from the center of the outer vertical plate to the groove of the adjacent plate surface; the inverted U-shaped connector consists of a connecting screw (8), a front fixing block (9) and a rear fixing block. The block (10) is composed of two parts: the front fixing block (9) and the rear fixing block (10) are two parts formed by splitting an inverted U-shaped body. The two parts are detachably fixed together by connecting screws (8). The size of the inverted U-shaped body is adapted to the size of the U-shaped frame and the through slot opened on the top surface of the front end of the first end ventilation module, which is perpendicular to the length direction of the large strain layer (1), so that it can be built into the U-shaped frame and clamped on both sides of the first end ventilation module inserted into the U-shaped frame by the through hole. The top of the inverted U-shaped connector is built into the through slot opened at the top surface of the first end ventilation module.

9. The simulated tendril variable curvature soft actuator according to claim 1, characterized in that, The control mechanism includes a first solenoid valve (16), a second solenoid valve (17), a PLC controller (18), a three-way connector (19), an air inlet line, an air delivery line, and an air venting line; wherein, one end of the air inlet line is connected to the first interface of the three-way connector (19) to form a connection, and the other end is connected to an external air source; one end of the air delivery line is connected to the second interface of the three-way connector (19) to form a connection, and the other end is connected to the other end of the third connecting air passage (11); one end of the air venting line is connected to the third interface of the three-way connector (19) to form a connection; the first solenoid valve (16) is installed on the air inlet line to control the opening / closing of the air inlet line; the second solenoid valve (17) is installed on the air venting line to control the opening / closing of the air venting line; the PLC controller (18) is electrically connected to the first solenoid valve (16) and the second solenoid valve (17) respectively to control the opening / closing of the first solenoid valve (16) and the second solenoid valve (17).

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