Soft-bodied manta ray robot and driving method based on thin film pneumatic driver

Abstract

The application discloses a soft manta ray robot based on a thin film pneumatic driver and a driving method. The soft manta ray robot comprises a trunk provided with a trunk skeleton, two pectoral fins provided on the two sides of the trunk along the span direction and provided with a pneumatic driver, the pneumatic driver comprises a first driver and a second driver respectively located at the two pectoral fins, the first driver and the second driver each comprise a driver skeleton and four pneumatic thin films, at each pectoral fin, two pneumatic thin films are arranged on the upper side of the driver skeleton and the other two pneumatic thin films are arranged on the lower side of the driver skeleton, and a gas chamber is formed between the two pneumatic thin films on the arbitrary side of the driver skeleton; and a control module is in communication with the four gas chambers respectively to periodically inflate or deflate the four gas chambers, so that the pneumatic beating of the pneumatic driver is realized to drive the soft manta ray robot to move. According to the soft manta ray robot based on the thin film pneumatic driver, the soft manta ray robot has more degrees of freedom and higher bionics.

Description

Technical Field

[0001] This invention relates to the field of biomimetic robot technology, and more specifically, to a soft manta ray-inspired robot based on a thin-film pneumatic actuator and a driving method thereof. Background Technology

[0002] Bionics, a research field that integrates biological science and engineering technology, has been a popular area of ​​scientific and technological research since the mid-20th century. In the marine field, fish have always been a key focus of bionics research. Fish possess remarkable mobility in water, exhibiting both highly efficient swimming and exceptional maneuverability in complex aquatic environments. Propeller-driven underwater vehicles, in terms of both propulsion efficiency and maneuverability, still lag significantly behind fish. Scholars have systematically studied fish bionics, analyzing and referencing their movement mechanisms to design and manufacture bionic robotic fish using mechanical, electronic, and even novel materials. These robotic fish simulate the movement of real fish, providing new design ideas for optimizing the propulsion principles and improving the maneuverability of underwater vehicles.

[0003] Compared to other fish, manta rays have certain advantages in terms of structure and function in their locomotion: First, as a classic fish that uses pectoral fin flapping and gliding in a central / paired fin propulsion mode, manta rays have the advantage of six degrees of freedom of movement, resulting in high flexibility and maneuverability in swimming; Second, manta rays have flat, wide, and symmetrical geometric features, which gives them greater stability when swimming compared to other fish with relatively slender bodies; Third, when the speed is fast enough, manta rays can even leap out of the water and complete a gliding maneuver.

[0004] In related technologies, biomimetic manta ray robots are mostly designed and manufactured using rigid actuation. These manta ray robots typically use motors to drive links or link assemblies to perform flapping or undulating movements. However, due to the limitations of the degrees of freedom in rigid structures, these manta ray robots suffer from drawbacks such as low biomimicry and poor mobility. Summary of the Invention

[0005] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, one object of the present invention is to provide a soft manta ray-inspired robot based on a thin-film pneumatic actuator, wherein the soft manta ray-inspired robot based on the thin-film pneumatic actuator has a large number of degrees of freedom, a high degree of biomimicry, and good mobility.

[0006] Another object of the present invention is to provide a driving method for driving the movement of the above-mentioned soft manta ray-like robot.

[0007] A soft manta ray-like robot based on a thin-film pneumatic actuator according to an embodiment of the present invention includes: a torso with a torso skeleton; two pectoral fins, the two pectoral fins being arranged longitudinally on both sides of the torso, each pectoral fin having a pneumatic actuator, the pneumatic actuator including a first actuator and a second actuator respectively located on the two pectoral fins, the first actuator and the second actuator each including an actuator skeleton and four pneumatic films arranged vertically, both actuator skeletons being connected to the torso skeleton, at each pectoral fin, two pneumatic films being located on the upper side of the actuator skeleton and two other pneumatic films being located on the lower side of the actuator skeleton, an air chamber being formed between two pneumatic films on any side of the actuator skeleton in the vertical direction; and a control module, the control module being connected to the four air chambers of the pneumatic actuator to periodically inflate or deflate the four air chambers to realize the pneumatic flapping of the pneumatic actuator to drive the soft manta ray-like robot to move, the movement including at least forward movement, turning, rising, and diving.

[0008] According to an embodiment of the present invention, the soft manta ray-inspired robot based on a thin-film pneumatic actuator can adjust the inflation volume of each air chamber through the inflation and deflation operations of the control module to drive the movement of the soft manta ray-inspired robot. The soft manta ray-inspired robot has a large number of degrees of freedom, a high degree of biomimicry, and good mobility.

[0009] In addition, the soft manta ray mimicry machine according to the above embodiments of the present invention may also have the following additional technical features:

[0010] According to some embodiments of the present invention, the pneumatic actuator is provided with four air vents that correspond one-to-one with the four air chambers. The air vents are located at the rear end of the pneumatic actuator and are connected to the control module. The air chambers are provided with multiple connected air passages that extend along the forward direction of the soft manta ray-like robot.

[0011] According to some embodiments of the present invention, the pectoral fin is provided with a connected pneumatic actuator and a flexible fin surface. The pneumatic actuator is located on the front side of the flexible fin surface. The pneumatic actuator generates a pneumatic flapping motion, which causes the flexible fin surface to generate flexible undulations to drive the soft manta ray-like robot to move.

[0012] According to some embodiments of the present invention, in the forward direction, the maximum size of the pectoral fin is L1, the maximum size of the actuator skeleton is L2, the maximum size of the flexible fin surface is L3, L2+L3=L1, L2<L1 / 2, L3>L1 / 2.

[0013] According to some embodiments of the present invention, the soft manta ray-like robot has a plurality of films connected sequentially in a vertical direction, the plurality of films including a first film, the middle portion of the first film covering the torso skeleton and the side portions covering the two pectoral fins, the side portions of the first film including a region covering the actuator skeleton and a region forming the flexible fin surface.

[0014] According to some embodiments of the present invention, the plurality of films further include a second film and two third films, wherein the middle portion of the second film covers a portion of the torso skeleton and the side portions cover the actuator skeleton, and the middle portion of the third film covers the torso skeleton and the side portions cover the actuator skeleton.

[0015] The soft manta ray-like robot includes a support structure, which includes the connected torso skeleton and two actuator skeletons. The first membrane and the second membrane are located on the upper side of the support structure, the second membrane is located on the upper side of the first membrane, and the two third membranes are located on the lower side of the support structure.

[0016] According to some embodiments of the present invention, the adjacent films are thermoplastically connected and adapted to form the air chamber.

[0017] According to some embodiments of the present invention, the soft manta ray-like robot includes a support structure, the support structure including the connected torso skeleton and two actuator skeletons, the support structure having a plurality of hollow portions, the hollow portions being elongated holes penetrating the support structure in the vertical direction, and the films located on both sides of the hollow portions in the vertical direction being thermoplastically connected through the hollow portions.

[0018] According to some embodiments of the present invention, the soft manta ray-like robot includes a support structure and a counterweight. The support structure includes the connected torso skeleton and two actuator skeletons. The counterweight is disposed on the support structure such that the density of the soft manta ray-like robot is greater than the density of water.

[0019] According to an embodiment of the present invention, a driving method is used to drive the movement of a soft manta ray-inspired robot based on a thin-film pneumatic actuator. A first actuator is located to the left of a second actuator. The first actuator includes an upper left air chamber and a lower left air chamber arranged vertically. The second actuator includes an upper right air chamber and a lower right air chamber arranged vertically. When the gas volume V1 in the air chamber is equal to a predetermined gas volume V2, the air chamber is in a fully inflated state; when 0 < V1 < V2, the air chamber is in a partially inflated state; and when V1 = 0, the air chamber is in a deflated state. The driving method includes: the control module in multiple cycles... The four air chambers are periodically inflated or deflated to bring them to a fully inflated, deflated, or partially inflated state, driving the soft manta ray-like robot to move. The movement of the soft manta ray-like robot in each cycle is as follows, with each cycle denoted as T: Within 0 to 0.5T, the control module keeps the upper left and upper right air chambers fully inflated and the lower left and lower right air chambers deflated, while the first and second actuators move upwards; Within 0.5T to T, the control module keeps the upper left and upper right air chambers deflated and the lower left air chamber... With the lower right air chamber in a fully inflated state, the first and second actuators move downwards; these actions drive the soft manta ray-like robot to perform a first forward motion of symmetrical up-and-down flapping. Alternatively, within 0 to 0.45T, the control module keeps the upper left and upper right air chambers in a fully inflated state, and the lower left and lower right air chambers in a deflated state, while the first and second actuators move upwards; within 0.45T to 0.9T, the control module keeps the upper left and upper right air chambers in a deflated state, and the lower left and lower right air chambers in a fully inflated state. The first and second actuators move downwards; within 0.9T to T, the control module keeps all four air chambers in the deflated state, and the first and second actuators are horizontal; the above actions drive the soft manta ray-like robot to perform a second forward motion of sequential up-and-down symmetrical flapping and sliding within a cycle; or, within 0 to 0.5T, the control module keeps the upper left and upper right air chambers in the partially inflated state, and the lower left and lower right air chambers in the deflated state, and the first and second actuators move upwards with a bending angle smaller than the bending angle in the fully inflated state; at 0...Within 5T to T, the control module keeps the upper left and upper right air chambers in the deflated state, and the lower left and lower right air chambers in the fully inflated state, while the first and second actuators move downwards; these actions drive the soft manta ray-like robot to perform a third forward movement of asymmetrical up-and-down flapping; or, within 0 to 0.5T, the control module keeps all four air chambers in the deflated state, and the first and second actuators are horizontal; within 0.5T to T, the control module keeps the upper left and lower right air chambers in the deflated state, while the first and second actuators are horizontal; The upper right air chamber is in the deflated state, and the lower left and lower right air chambers are in the fully inflated state. The first and second actuators move downwards. These actions drive the soft manta ray-like robot to perform a fourth forward movement, moving downwards. Alternatively, within 0 to 0.5T, the control module keeps the upper left air chamber in the deflated state, and the lower left, upper right, and lower right air chambers in the fully inflated state. The first actuator moves downwards, and the second actuator moves horizontally. Within 0.5T to T, the control module... The block ensures that all four air chambers are in the deflated state, with the first and second actuators horizontal; this action drives the soft manta ray-like robot to turn right; or, within 0 to 0.5T, the control module ensures that the upper right air chamber is in the deflated state, while the upper left, lower left, and lower right air chambers are in the fully inflated state, with the first actuator horizontal and the second actuator moving downwards; within 0.5T to T, the control module ensures that all four air chambers are in the deflated state, with the first... The first and second actuators are horizontal; the above actions drive the soft manta ray-like robot to turn left; or, the control module inflates the four air chambers, so that all four air chambers are in a fully inflated state, with the first and second actuators horizontal, driving the soft manta ray-like robot to rise; or, the control module deflates the four air chambers, so that all four air chambers are in a deflated state, with the first and second actuators horizontal, driving the soft manta ray-like robot to descend.

[0020] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0022] Figure 1 This is a perspective view of a soft manta ray-like robot according to a first embodiment of the present invention, wherein the control module is not shown;

[0023] Figure 2 This is a perspective view of a soft manta ray-like robot according to a second embodiment of the present invention, wherein the control module is not shown;

[0024] Figure 3 This is a perspective view of a soft manta ray-like robot according to a third embodiment of the present invention, wherein the control module and the lowermost third membrane are not shown;

[0025] Figure 4 This is a schematic diagram of the cooperation structure between the control module and the vent according to an embodiment of the present invention;

[0026] Figure 5 yes Figure 3 The center circle shows a magnified view of point A.

[0027] Figure 6 yes Figure 3 Top view;

[0028] Figure 7 This is a top view of the first thin film according to an embodiment of the present invention;

[0029] Figure 8 This is a top view of the second thin film according to an embodiment of the present invention;

[0030] Figure 9 This is a top view of the third thin film according to an embodiment of the present invention;

[0031] Figure 10 This is a top view of the support structure according to an embodiment of the present invention;

[0032] Figure 11 This is an exploded view of the support structure and two third films on the underside of the support structure according to an embodiment of the present invention;

[0033] Figure 12 This is a schematic diagram of the control program of the control module according to an embodiment of the present invention.

[0034] Figure label:

[0035] Soft manta ray-inspired robot 100;

[0036] Torso 10; Torso skeleton 11;

[0037] Pectoral fin 20; pneumatic actuator 21; actuator skeleton 211; pneumatic membrane 212; air chamber 213; air passage 214; vent 215; first actuator 22; second actuator 23; flexible fin surface 24;

[0038] Control module 30; Control source electrical equipment 31; Flexible hose 32;

[0039] Thin film 40; First thin film 41; Second thin film 42; Third thin film 43; Middle portion 401; Side portions 402;

[0040] Support structure 50; Hollowed-out part 51;

[0041] Thermoplastic path 60;

[0042] Spanning direction F1; Up and down direction F2; Forward direction F3; Axis of symmetry N1. Detailed Implementation

[0043] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0044] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0045] In the description of this invention, "first feature" and "second feature" may include one or more of the features, "multiple" means two or more, "above" or "below" the second feature may include the first and second features being in direct contact, or the first and second features being in contact through another feature between them, and "above," "over," and "on top" the second feature may include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0046] The rapid development of soft robotics technology has provided more mature and feasible new ideas for the flexible actuation design of robotic fish. Compared with traditional rigid robots, soft robots can achieve more degrees of freedom and higher maneuverability. The actuation methods for soft robots mainly include fluid actuation, dielectric elastomers, shape memory materials, magnetic actuation, and ion-exchange polymer-metal composite materials. Underwater operations are complex, often facing challenges such as current disturbances, low visibility, and numerous obstacles. These complex working environments demand high maneuverability and diverse functionalities from robotic fish. The aforementioned flexible actuation technologies have opened up broader application prospects for the motion design and diverse functional integration of robotic fish.

[0047] Therefore, this application proposes a soft manta ray-inspired robot based on a thin-film pneumatic actuator. The soft manta ray-inspired robot based on the thin-film pneumatic actuator can achieve stable, efficient and highly maneuverable movements similar to those of a manta ray underwater, which is conducive to creating a solid foundation for further functional development of the robot.

[0048] The following description, with reference to the accompanying drawings, describes a soft manta ray-inspired robot 100 based on a thin-film pneumatic actuator according to an embodiment of the present invention.

[0049] Reference Figures 1-11 As shown, the soft manta ray-inspired robot 100 based on a thin-film pneumatic actuator according to an embodiment of the present invention may include a torso 10, two pectoral fins 20 and a control module 30.

[0050] The torso 10 is provided with a torso frame 11, which has a certain rigidity to prevent the torso 10 from curling or deforming. For example, the material of the torso frame 11 is PVC (polyvinyl chloride). Of course, the torso 10 may also be provided with other components.

[0051] Two pectoral fins 20 are positioned on either side of the trunk 10 along a span direction F1, where span direction F1 is the orientation of the two pectoral fins 20. For example, span direction F1 is... Figures 1-3 The left and right directions are shown. It should be noted that in this application, the span direction F1, the up and down direction F2, and the forward direction F3 are all perpendicular to each other and are all based on the soft manta ray robot 100. The descriptions of the up, down, forward, backward, left and right directions are all based on the directions marked in the attached figures.

[0052] The two pectoral fins 20 are equipped with pneumatic actuators 21, which include a first actuator 22 and a second actuator 23 located on the two pectoral fins 20 respectively. For example Figures 1-3 As shown, the first actuator 22 is located on the left pectoral fin 20, and the second actuator 23 is located on the right pectoral fin 20.

[0053] Both the first actuator 22 and the second actuator 23 include an actuator frame 211 and four pneumatic membranes 212 arranged in the vertical direction. The actuator frame 211 has a certain rigidity to prevent the first actuator 22 and the second actuator 23 from curling or deforming. For example, the material of the actuator frame 211 is PVC (polyvinyl chloride). Both actuator frames 211 are connected to the torso frame 11, making the soft manta ray robot 100 less prone to curling or deforming as a whole, which helps to improve the movement stability of the soft manta ray robot 100 in water.

[0054] At each pectoral fin 20, two pneumatic membranes 212 are disposed on the upper side of the actuator frame 211, and another two pneumatic membranes 212 are disposed on the lower side of the actuator frame 211. An air chamber 213 is formed between the two pneumatic membranes 212 on either side of the actuator frame 211 in the vertical direction, so that each pectoral fin 20 has one air chamber 213 on the upper side of the actuator frame 211 and one air chamber 213 on the lower side of the actuator frame 211, so that the entire soft manta ray robot 100 has four air chambers 213.

[0055] For example, in some embodiments, such as Figures 1-3 As shown, the first actuator 22 is located to the left of the second actuator 23. The first actuator 22 includes an upper left air chamber 213 and a lower left air chamber 213 arranged in the vertical direction F2. The second actuator 23 includes an upper right air chamber 213 and a lower right air chamber 213 arranged in the vertical direction F2.

[0056] The pneumatic diaphragm 212 can deform, allowing it to deform during the inflation or deflation of the air chamber 213, thereby causing the pneumatic actuator 21 to bend. For example, the material of the pneumatic diaphragm 212 is TPU (thermoplastic polyurethane elastomer).

[0057] The control module 30 is connected to the four air chambers 213 of the pneumatic actuator 21 to periodically inflate or deflate the four air chambers 213, thereby realizing the pneumatic flapping of the pneumatic actuator 21 to drive the soft manta ray-like robot 100 to move. The movement includes at least forward movement, turning, rising and diving.

[0058] For example Figures 1-4 As shown, the control module 30 includes a control source electrical device 31 and a flexible hose 32. The control source electrical device 31 includes control components, an air source, a valve body, and an air pump. The control source electrical device 31 is connected to the air chamber 213 through the flexible hose 32, and can inflate or deflate the air chamber 213 through the flexible hose 32. The range of motion of the soft manta ray-like robot 100 can be adjusted by adjusting the length of the flexible hose 32.

[0059] By inflating or deflating each air chamber 213 through the control module 30, the inflation and deflation volume and inflation rate of each air chamber 213 can be controlled to adjust the movement mode of the pneumatic actuator 21 at each pectoral fin 20, such as flapping upwards, flapping downwards, or maintaining horizontal position, thereby driving the soft manta ray-like robot 100 to move.

[0060] Specifically, at each pectoral fin 20, the control module 30 inflates the upper air chamber 213 and deflates the lower air chamber 213, causing the two pneumatic membranes 212 forming the upper air chamber 213 to expand and deform. The actuator frame 211 also bends upward under the influence of the pneumatic membranes 212, enabling the pneumatic actuator 21 at that pectoral fin 20 to bend upward, thus causing the pectoral fin 20 to flap upward. When the pectoral fin 20 flaps, it interacts with the water, and the combined force provides thrust to the soft manta ray-inspired robot 100, mimicking the real movement of a manta ray. For example, after the pneumatic actuator 21 bends upward, causing the pectoral fin 20 to flap upward, the angle between the pectoral fin 20 and the body 10 changes from 0° to 8°, 18°, or other angles. Controlling the amount of air in the air chamber 213 can control the degree of bending of the pneumatic actuator 21 at the pectoral fin 20. For example, maximizing the amount of air in the air chamber 213 without damaging the pneumatic actuator 21 can cause the pneumatic actuator 21 at the pectoral fin 20 to bend to the maximum extent. Reducing the amount of air in the air chamber 213 can reduce the degree of bending of the pneumatic actuator 21 at the pectoral fin 20 until the pneumatic actuator 21 remains horizontal.

[0061] Similarly, by deflating the upper air chamber 213 and inflating the lower air chamber 213 through the control module 30, the pneumatic actuator 21 at the pectoral fin 20 can be made to flap downwards, thus causing the pectoral fin 20 to flap downwards. By simultaneously inflating or deflating the upper and lower air chambers 213 through the control module 30, the pneumatic actuator 21 at the pectoral fin 20 can be kept horizontal, thus keeping the pectoral fin 20 horizontal.

[0062] The control module 30 controls the inflation volume in each air chamber 213 to control the state of the two pectoral fins 20, enabling the soft manta ray-inspired robot 100 to perform actions such as forward movement, turning, rising, and diving. By increasing or decreasing the weight of the torso frame 11 and adding counterweights to the torso frame 11, the density of the submerged portion of the soft manta ray-inspired robot 100 is made slightly greater than the density of water, thus increasing the weight of the soft manta ray-inspired robot 100.

[0063] For example, by controlling the inflation level of the four air chambers 213 to 0 using the control module 30, the soft manta ray-like robot 100 can achieve diving motion under the action of gravity. By controlling the inflation level of the four air chambers 213 to the maximum inflation level that prevents damage to the pneumatic actuator 21, the soft manta ray-like robot 100 can achieve ascending motion under the action of buoyancy. By controlling the inflation and deflation of the four air chambers 213 using the control module 30, the two pectoral fins 20 can be made to flap upwards, downwards, upwards, etc., enabling the soft manta ray-like robot 100 to achieve forward motion. By controlling the inflation and deflation of the four air chambers 213 using the control module 30, the left pectoral fin 20 of the soft manta ray-like robot 100 can be made to flap upwards, downwards, upwards, etc., while the right pectoral fin 20 remains horizontal, enabling the soft manta ray-like robot 100 to achieve rightward turning motion.

[0064] The air chamber 213 is formed by adjacent pneumatic membranes 212, so that the pneumatic membrane 212 is affected first during the inflation and deflation of the air chamber 213. The pneumatic membrane 212 is more easily deformed than the actuator frame 211 and requires less deformation force. Therefore, it is beneficial to reduce the difficulty of inflating the air chamber 213 and making the flapping amplitude of the soft manta ray robot 100 more controllable, and the flapping angle range of the pectoral fin 20 is larger, which helps to improve the biomimicry of real manta rays.

[0065] In this application, the pneumatic actuators 21 at the two pectoral fins 20 enable the soft manta ray-inspired robot 100 to flap its two pectoral fins 20 upwards and downwards respectively, achieving good biomimetic effect and high degree of biomimicry. Compared with the design of traditional manta ray-inspired robotic fish, the soft manta ray-inspired robot 100 of this invention objectively closer to the real movement mechanism of manta rays, with more degrees of freedom, higher biomimetic degree, and better movement mobility.

[0066] The rigidity of the torso skeleton 11 and the actuator skeleton 211 is higher than that of the aerodynamic membrane 212, allowing the torso skeleton 11 and actuator skeleton 211 to mimic the skeleton of a real manta ray. The torso skeleton 11 and actuator skeleton 211 not only improve the rigidity of the soft manta ray-like robot 100, making it less susceptible to water flow during the complete deformation of the pectoral fin 20, but also enable it to complete the intended movements with higher quality. Furthermore, the torso skeleton 11 and actuator skeleton 211 allow for control over the degree of deformation of the soft manta ray-like robot 100, making its deformation more controllable and achieving a higher degree of biomimicry to a real manta ray.

[0067] Furthermore, this application drives the movement of the soft manta ray robot 100 by inflating or deflating the air chamber 213, eliminating the need for a built-in motor in the underwater part of the soft manta ray robot 100. This results in low operating noise and minimizes noise interference to the underwater environment.

[0068] According to an embodiment of the present invention, the soft manta ray-like robot 100 can adjust the amount of air in each air chamber 213 by controlling the inflation and deflation operations of each air chamber 213 through the control module 30, so as to drive the soft manta ray-like robot 100 to move. The soft manta ray-like robot 100 has a large number of degrees of freedom of movement, a high degree of biomimicry, and good mobility.

[0069] The embodiments of the present invention can improve the transparency of the underwater structures of the torso 10, pectoral fins 20 and control module 30, thereby improving the stealth of the soft manta ray-like robot 100 in water and facilitating underwater missions with stealth requirements.

[0070] In some embodiments, the thickness of the torso skeleton 11 and the actuator skeleton 211 is 0.4 mm, and the thickness of the pneumatic membrane 212 is 0.2 mm, so that the maximum thickness of the soft manta ray-like robot 100 in its normal state is only 1.2 mm. This allows the thickness of the soft manta ray-like robot 100 in its normal state to be controlled within 1.5 mm, making the soft manta ray-like robot 100 approximately a planar two-dimensional structure in its normal state. This enables the soft manta ray-like robot 100 to have flat and wide geometric features, which helps to reduce the resistance encountered by the soft manta ray-like robot 100 in water movement and improves the movement stability. Here, "normal state" refers to the state in which the soft manta ray-like robot 100 is fully extended and not moving, for example... Figures 1-3 The state of the soft manta ray robot 100 shown.

[0071] The air chamber 213 can be formed by thermoplastic connection or bonding of adjacent pneumatic films 212 along a specific path. For example... Figures 1-3 and Figures 4-6 As shown, adjacent pneumatic films 212 are thermoplastically connected along the thermoplastic path 60, which can form an air chamber 213 between two adjacent pneumatic films 212.

[0072] In some embodiments of the present invention, such as Figures 1-3 and Figures 5-6 As shown, the pneumatic actuator 21 has four vents 215 that correspond one-to-one with the four air chambers 213. The vents 215 are connected to the control module 30, allowing the control module 30 to inflate or deflate the four air chambers 213 through the four vents 215 respectively. For example, each of the four air chambers 213 has a vent 215 on its rear side.

[0073] The vent 215 is located at the rear end of the pneumatic actuator 21. Here, the rear end refers to the rear end along the forward direction F3 of the soft manta ray robot 100. This makes the soft manta ray robot 100 less susceptible to interference from the connection structure between the control module 30 and the vent 215, such as the flexible hose 32, during its movement, thus making the movement of the soft manta ray robot 100 smoother.

[0074] The air chamber 213 contains multiple interconnected air passages 214, which extend along the forward direction F3 of the soft manta ray-like robot 100. The multiple air passages 214 can be connected at their ends or in the middle, and can be directly or indirectly connected, ensuring that the different air passages 214 within the entire air chamber 213 are interconnected. For example, in some embodiments, such as... Figures 1-3 and Figures 5-6 As shown, each of the four air chambers 213 is provided with multiple air passages 214 extending in the front-to-back direction, and the adjacent air passages 214 in each air chamber 213 are directly connected at the front and rear ends.

[0075] Controlling the inflation and deflation of each air chamber 213 enables the soft manta ray-inspired robot 100 to move forward, turn, rise, or dive. Each air chamber 213 has multiple interconnected air channels 214 extending along the forward direction F3. These air channels guide the undulations of the pectoral fin 20 during movement, facilitating undulations in the pectoral fin 20 similar to those of a real manta ray. This allows for better control of the amplitude of the undulations, resulting in greater stability, increased biomimicry, and improved movement efficiency of the soft manta ray-inspired robot 100.

[0076] For example, in some embodiments, such as Figures 1-3 As shown, through the multiple air passages 214 extending in the front-to-back direction in the upper left air chamber 213 and the lower left air chamber 213, the first actuator 22 on the left side can be divided into multiple parts extending in the front-to-back direction in the left-to-right direction. Each part moves upward or downward independently to achieve the oscillation of the first actuator 22 in the spanwise direction F2.

[0077] In some embodiments of the present invention, such as Figure 1 As shown, the pneumatic actuator 21 can be distributed throughout the entire pectoral fin 20, so that the air chamber 213 is distributed throughout the entire pectoral fin 20, realizing full-fin surface drive to propel the robot forward.

[0078] In other embodiments, such as Figures 2-3 and Figures 5-7 As shown, the pectoral fin 20 is equipped with a connected pneumatic actuator 21 and a flexible fin surface 24. The pneumatic actuator 21 is located in front of the flexible fin surface 24. The pneumatic actuator 21 generates a pneumatic flapping motion, which causes the flexible fin surface 24 to generate flexible undulations to drive the soft manta ray-inspired robot 100 to move. The pneumatic actuator 21 can generate a pneumatic flapping motion along the spanwise direction F2, and the flexible fin surface 24 can generate flexible undulations along the flow direction.

[0079] Each pectoral fin 20 includes a pneumatic actuator 21 located on the front side and a flexible fin surface 24 located on the rear side. The pneumatic actuator 21 actively drives the front side of the pectoral fin 20 to flap and causes the flexible fin surface 24 on the rear side of the pectoral fin 20 to undulate, which can realize semi-fin surface drive and achieve active-passive hybrid drive. This is beneficial to improve the stability of the soft manta ray robot 100 in its forward, turning, rising and diving movements. The soft manta ray robot 100 has a better biomimetic movement effect of real manta rays.

[0080] In some embodiments, such as Figure 6 As shown, in the forward direction F3, the maximum size of the pectoral fin 20 is L1, the maximum size of the actuator skeleton 211 is L2, and the maximum size of the flexible fin surface 24 is L3, where L2 + L3 = L1, L2 < L1 / 2, and L3 > L1 / 2. By having a small portion of the pectoral fin 20 covered by the pneumatic actuator 21 and the majority covered by the flexible fin surface 24 along the forward direction F3, the passive drive portion of the pectoral fin 20 can be designed by adjusting the shape and size of the flexible fin surface 24. This allows for adjustment of the distribution and proportion of active and passive drives, facilitating the obtaining of data that best matches a real manta ray and improving the propulsion efficiency of the soft manta ray-inspired robot 100.

[0081] The flexible fin surface 24 is formed of a thin film 40. An excessive number of thin films 40 forming the flexible fin surface 24 can lead to water ingress between adjacent films 40, making the passively driven movement of the flexible fin surface 24 unstable. In some embodiments of this application, such as... Figures 2-3 and Figures 5-7 As shown, the soft manta ray-like robot 100 has a plurality of films 40 connected sequentially along the vertical direction F2. The plurality of films 40 include a first film 41. The middle portion 401 of the first film 41 covers the torso skeleton 11, and the side portions 402 cover two pectoral fins 20. The side portions 402 of the first film 41 include a region covering the actuator skeleton 211 and a region forming the flexible fin surface 24.

[0082] The first membrane 41 makes the passive driving part of the pectoral fin 20, namely the flexible fin surface 24, formed by a single membrane 40. The single membrane 40 has better wave stability with the water body, and the flexible fin surface 24 is less disturbed, making the movement of the flexible fin surface 24 more stable, which is conducive to improving the movement stability of the soft manta ray robot 100.

[0083] In some embodiments, such as Figures 2-3 and Figures 5-11As shown, the plurality of films 40 also include a second film 42 and two third films 43. The middle portion 401 of the second film 42 covers a portion of the torso skeleton 11, and the two side portions 402 cover the actuator skeleton 211. The middle portion 401 of the third film 43 covers the torso skeleton 11, and the two side portions 402 cover the actuator skeleton 211. The soft manta ray-like robot 100 includes a support structure 50, which includes a torso skeleton 11 and two actuator skeletons 211 connected to each other. The first film 41 and the second film 42 are located on the upper side of the support structure 50, with the second film 42 located on the upper side of the first film 41, and the two third films 43 located on the lower side of the support structure 50.

[0084] That is, the underwater portion of the soft manta ray-inspired robot 100 includes a second membrane 42, a first membrane 41, a support structure 50, a third membrane 43, and another third membrane 43 stacked sequentially from top to bottom. The torso 10 includes the middle portion 401 of the second membrane 42, the middle portion 401 of the first membrane 41, the torso skeleton 11, the middle portion 401 of the third membrane 43, and the middle portion 401 of the third membrane 43 stacked sequentially from top to bottom. The pectoral fin 20 includes the side portions 402 of the second membrane 42, the side portions 402 of the first membrane 41, the actuator skeleton 211, the side portions 402 of the third membrane 43, and the side portions 402 of the third membrane 43 stacked sequentially from top to bottom. At the pectoral fin 20, the front side of the side portions 402 of the first membrane 41, the side portions 402 of the second membrane 42, and the side portions 402 of the third membrane 43 form the pneumatic membrane 212 of the pneumatic actuator 21, and the rear side of the side portions 402 of the first membrane 41 forms the flexible fin surface 24.

[0085] The first film 41, the second film 42, and the third film 43 can all cover the actuator frame 211 and can connect adjacent first films 41 and third films 43 on the outside of the actuator frame 211, so that the actuator frame 211 is wrapped between adjacent films 40. The actuator frame 211 and the adjacent films 40 are less likely to have a large amount of water entering between them, which would affect the deformation of the pneumatic actuator 40. This is beneficial to improving the controllability of the pneumatic flapping of the pneumatic actuator 40, so as to control the movement of the soft manta ray robot 100 and improve the movement stability of the soft manta ray robot 100.

[0086] The support structure 50 can improve the overall rigidity of the soft manta ray robot 100, making it less prone to curling and deformation in water. This facilitates the control of the bending deformation of the pneumatic actuator 21 in the soft manta ray robot 100 to generate pneumatic flapping, and drives the flexible fin surface 24 to generate flexible undulation, thereby improving the biomimetic motion effect of the soft manta ray robot 100.

[0087] In addition, both the first membrane 41 and the second membrane 42 are located on the upper side of the support structure 50, and the second membrane 42 is located on the upper side of the first membrane 41. This facilitates the installation of a flexible hose 32 or other structures at the air vent 215 of the air chamber 213 on the upper side of the first membrane 42 to connect the control source electrical equipment 31 of the control module 30. This reduces the interference of the flexible hose 32 on the flexible fin surface 24 of the first membrane 41, resulting in a better flexible undulation effect of the soft manta ray robot 100.

[0088] The shape of the soft manta ray-inspired robot 100 can be adjusted to change its motion parameters, thereby approximating the motion performance of a real manta ray. For example, in some embodiments of the present invention, such as... Figure 2 As shown, the front end of the soft manta ray-inspired robot 100 is a plane extending along the span direction F2, achieving a flat leading edge fin surface.

[0089] For example, in some embodiments, such as Figure 3 and Figures 5-6 As shown, the front end of the soft manta ray-inspired robot 100 protrudes forward from both ends towards the middle. The projection of the soft manta ray-inspired robot 100 in the vertical direction F2 is an axisymmetric shape with a spanwise dimension F1 larger than the forward dimension F3. The axis of symmetry N1 is parallel to the forward direction F3, making the shape of the soft manta ray-inspired robot 100 similar to that of a real manta ray, achieving a slanted leading-edge fin surface. After multiple rounds of debugging, the soft manta ray-inspired robot 100 was designed with a slanted leading-edge fin surface, which helps reduce the flow resistance in water and improve the motion stability of the soft manta ray-inspired robot 100. For example, the soft manta ray-inspired robot 100 is roughly axisymmetrically kite-shaped in the spanwise direction F2, and its front end is chamfered and rounded to form a streamlined shape, which helps reduce resistance in the aquatic environment.

[0090] In some embodiments, such as Figures 1-3 and Figure 6 As shown, the rear end of the support structure 50 extends to form a tail-like structure, which plays a role in balancing the counterweight and stabilizing the movement of the soft manta ray robot 100.

[0091] In some embodiments of the present invention, such as Figures 1-3 and Figures 5-6 As shown, adjacent films 40 are thermoplastically connected, forming an air chamber 213. That is, adjacent films 40 are thermoplastically connected, which is simple to operate and provides a strong connection. The thermoplastic connection also allows for the formation of an air chamber 213, for example, according to... Figures 1-3 and Figures 5-6 The thermoplastic path 60 shown thermoplastically connects two adjacent films 40, which can form an air passage 214 between adjacent thermoplastic paths 60, thereby forming an air chamber 213.

[0092] By connecting the films 40 through thermoplastic bonding, not only can the connection strength be improved and the connection difficulty be simplified, but an air chamber 213 can also be formed. There is no need to add a step to form the air chamber 213, so the steps of connecting adjacent films 40 and forming an air chamber 213 between adjacent films 40 can be combined into one step, which helps to simplify the manufacturing process of the soft manta ray robot 100.

[0093] In some embodiments of the present invention, such as Figures 1-3 , Figure 6 and Figures 10-11 As shown, the soft manta ray-inspired robot 100 includes a support structure 50, which includes a connected torso skeleton 11 and two actuator skeletons 211. The support structure 50 has multiple hollow sections 51, which are elongated holes that penetrate the support structure 50 along the vertical direction F2. Thin films 40 located on both sides of the hollow section 51 along the vertical direction F2 are thermoplastically connected through the hollow section 51.

[0094] The perforated portion 51 not only allows the films 40 on both sides of the perforated portion 51 to be thermoplastically connected at the perforated portion 51, but also confines the support structure 50 between the two films 40. This reduces the possibility of the support structure 50 moving relative to the films 40 during the movement of the soft manta ray-inspired robot 100, thereby improving the movement stability and biomimicry of the soft manta ray-inspired robot 100. Furthermore, the perforated portion 51 is an elongated hole, which helps to increase the thermoplastic connection area and improve the connection strength between adjacent films 40.

[0095] In some embodiments, such as Figures 1-3 , Figure 6 and Figures 10-11 As shown, the front end and middle of the torso frame 11 are provided with multiple hollowed-out portions 51, and the first film 41 on the upper side and the third film 43 on the lower side of the torso frame 11 can be thermoplastically connected at the hollowed-out portions 51.

[0096] In some embodiments, such as Figures 1-3 and Figure 6 As shown, the thermoplastic path 60 is designed not only in the hollow part 51, but also on the circumferential outer side of the support structure 50, so that the films 40 on both sides of the support structure 50 in the vertical direction F2 are thermoplastically connected on the outer side of the support structure 50 to wrap the support structure 50, reduce the movement of the support structure 50, reduce the possibility of water entering between the support structure 50 and the film 40, and help improve the motion stability of the soft manta ray robot 100.

[0097] In some embodiments of the present invention, the soft manta ray-inspired robot 100 further includes a support structure 50 and a counterweight. The counterweight is disposed on the support structure 50, making the density of the soft manta ray-inspired robot 100 slightly greater than the density of water. The counterweight can be detachably or fixedly disposed on the support structure 50.

[0098] By adjusting the weight and installation position of the counterweights, the overall weight and center of gravity of the soft manta ray robot 100 can be adjusted, making the density of the soft manta ray robot 100 slightly greater than that of water. This allows the soft manta ray robot 100 to dive when all four air chambers 213 are deflated and to rise when all four air chambers 213 are filled with air, and also improves the stability of the soft manta ray robot 100's forward, turning, rising, and diving movements.

[0099] The driving method according to an embodiment of the present invention is used to drive the movement of a soft manta ray-inspired robot 100 based on a thin-film pneumatic actuator according to an embodiment of the present invention.

[0100] The first actuator 22 is located to the left of the second actuator 23. The first actuator 22 includes an upper left air chamber 213 and a lower left air chamber 213 arranged in the vertical direction F2. The second actuator 23 includes an upper right air chamber 213 and a lower right air chamber 213 arranged in the vertical direction F2. When the gas volume V1 in the air chamber 213 is equal to the predetermined gas volume V2, the air chamber 213 is in a fully filled state; when 0 < V1 < V2, the air chamber 213 is in a partially filled state; when V1 = 0, the air chamber 213 is in a completely vented state. The predetermined gas volume V2 can be determined according to actual experiments, and this application does not limit the specific value of V2.

[0101] The driving methods include:

[0102] S1: The control module 30 periodically inflates or deflates the four air chambers 213 within multiple cycles T, so that the air chambers 213 are in a fully inflated state, a deflated state, or a partially inflated state, thereby driving the soft manta ray-like robot 100 to move.

[0103] The motion of the soft manta ray-like robot 100 within each cycle T is as follows, where each cycle is denoted as T.

[0104] By periodically inflating or deflating the four air chambers 213 through the control module 30, after multiple cycles T, that is, after repeating any one of the steps S21, S22, S23, S24, S25, S26, S27 and S28, the soft manta ray-like robot 100 can perform various movements.

[0105] S21: Within 0 to 0.5T, the control module 30 keeps the upper left and upper right air chambers 213 fully inflated and the lower left and lower right air chambers 213 deflated, while the first actuator 22 and the second actuator 23 move upwards. Within 0.5T to T, the control module 30 keeps the upper left and upper right air chambers 213 deflated and the lower left and lower right air chambers 213 fully inflated, while the first actuator 22 and the second actuator 23 move downwards. These actions (referring to the individual flapping or horizontal movements of the first actuator 22 and the second actuator 23) drive the soft manta ray-like robot 100 to perform a first forward movement of symmetrical up-and-down flapping.

[0106] S21 shows the inflation and deflation states of the four air chambers 213 within one cycle T. After multiple cycles T, the first actuator 22 and the second actuator 23 periodically oscillate upward, downward, and upward again. Furthermore, the bending angles of the pneumatic actuator 21 are approximately the same when fully inflated (e.g., bending upward or downward by 18°), ensuring that the upward and downward oscillation angles of the first actuator 22 and the second actuator 23 are consistent. This achieves symmetrical upward and downward oscillations of the first actuator 22 and the second actuator 23, driving the soft manta ray-like robot 100 to perform a first forward motion of symmetrical upward and downward oscillations.

[0107] S22: Within 0 to 0.45T, the control module 30 keeps the upper left and upper right air chambers 213 fully inflated and the lower left and lower right air chambers 213 deflated, while the first actuator 22 and the second actuator 23 move upwards. Within 0.45T to 0.9T, the control module 30 keeps the upper left and upper right air chambers 213 deflated and the lower left and lower right air chambers 213 fully inflated, while the first actuator 22 and the second actuator 23 move downwards. Within 0.9T to T, the control module 30 keeps all four air chambers 213 deflated and the first actuator 22 and the second actuator 23 horizontal. These actions drive the soft manta ray-like robot 100 to perform a second forward motion of sequential up-and-down symmetrical flapping and gliding within a cycle.

[0108] S22 shows the inflation and deflation states of the four air chambers 213 within one cycle T. After multiple cycles T, the first actuator 22 and the second actuator 23 periodically oscillate upward, downward, horizontal, and upward movements... The horizontal movement of the pneumatic actuator 21 means that the pneumatic actuator 21 and the torso 10 are approximately on the same plane. Furthermore, the bending angle of the pneumatic actuator 21 in the fully inflated state is approximately the same (e.g., bending upward or downward by 18°), ensuring that the upward and downward oscillation angles of the first actuator 22 and the second actuator 23 are consistent. This achieves a combination of symmetrical upward and downward oscillation and sliding of the first actuator 22 and the second actuator 23, driving the soft manta ray-like robot 100 to perform a second forward motion of symmetrical upward and downward oscillation and sliding.

[0109] S23: Within 0 to 0.5T, the control module 30 keeps the upper left and upper right air chambers 213 partially inflated and the lower left and lower right air chambers 213 fully deflated. The first actuator 22 and the second actuator 23 move upwards with a bending angle smaller than that in the fully inflated state. Within 0.5T to T, the control module 30 keeps the upper left and upper right air chambers 213 fully deflated and the lower left and lower right air chambers 213 fully inflated. The first actuator 22 and the second actuator 23 move downwards. These actions drive the soft manta ray-like robot 100 to perform a third forward movement of asymmetrical up-and-down flapping.

[0110] S23 shows the inflation and deflation states of the four air chambers 213 within one cycle T. After multiple cycles T, the first actuator 22 and the second actuator 23 periodically oscillate upward, downward, and upward again. The bending angle of the pneumatic actuator 21 is different in the fully inflated state and the partially inflated state. For example, in the fully inflated state, the pneumatic actuator 21 bends upward or downward by 18°, and in the partially inflated state, the pneumatic actuator 21 bends upward or downward by 8°. This makes the upward and downward oscillation angles of the first actuator 22 and the second actuator 23 inconsistent, realizing the asymmetrical oscillation of the first actuator 22 and the second actuator 23, driving the soft manta ray robot 100 to perform the third forward motion of asymmetrical oscillation.

[0111] S24: Within 0 to 0.5T, the control module 30 ensures all four air chambers 213 are fully deflated, and the first actuator 22 and the second actuator 23 are horizontal. Within 0.5T to T, the control module 30 ensures the upper left and upper right air chambers 213 are fully deflated, and the lower left and lower right air chambers 213 are fully inflated, causing the first actuator 22 and the second actuator 23 to flap downwards. These actions drive the soft manta ray-like robot 100 to perform a fourth forward movement of flapping downwards.

[0112] S24 shows the inflation and deflation states of the four air chambers 213 within one cycle T. After multiple cycles T, the first actuator 22 and the second actuator 23 periodically cycle horizontally, downwardly, horizontally, etc., so that the first actuator 22 and the second actuator 23 cycle downwardly, driving the soft manta ray robot 100 to perform the third forward motion of downward flapping.

[0113] S25: Within 0 to 0.5T, the control module 30 deflates the upper left air chamber 213, while filling the lower left, upper right, and lower right air chambers 213. The first actuator 22 moves downwards, and the second actuator 23 moves horizontally. Within 0.5T to T, the control module 30 deflates all four air chambers 213, and the first and second actuators 22 and 23 move horizontally. These actions drive the soft manta ray-like robot 100 to turn to the right.

[0114] S25 shows the inflation and deflation states of the four air chambers 213 within one cycle T. After multiple cycles T, the first actuator 22 periodically flaps downwards, horizontally, and downwards again, while the second actuator 23 remains horizontal. The second actuator 23 is located to the right of the first actuator 22, driving the soft manta ray-like robot 100 to make a rightward turning motion.

[0115] S26: Within 0 to 0.5T, the control module 30 deflates the upper right air chamber 213, while filling the upper left, lower left, and lower right air chambers 213. The first actuator 22 is horizontal, and the second actuator 23 moves downwards. Within 0.5T to T, the control module 30 deflates all four air chambers 213, and the first and second actuators 22 are horizontal. These actions drive the soft manta ray-like robot 100 to turn to the left.

[0116] S26 shows the inflation and deflation states of the four air chambers 213 within one cycle T. After multiple cycles T, the first actuator 22 is always in a horizontal state, while the second actuator 23 periodically flaps downward, horizontally, and downward again... The first actuator 22 is located to the left of the second actuator 23, driving the soft manta ray robot 100 to make a turning motion to the left.

[0117] S27: The control module 30 inflates the four air chambers 213, so that all four air chambers 213 are in a fully inflated state. The first driver 22 and the second driver 23 are horizontal, driving the soft manta ray robot 100 to move upward.

[0118] With all four air chambers 213 filled with air, the density of the soft manta ray robot 100 is slightly less than that of water, allowing the soft manta ray robot 100 in S27 to rise under the action of buoyancy.

[0119] S28: The control module 30 releases air from the four air chambers 213, so that all four air chambers 213 are in a fully deflated state. The first driver 22 and the second driver 23 are horizontal, driving the soft manta ray robot 100 to dive.

[0120] With all four air chambers 213 in a deflated state, the density of the soft manta ray robot 100 is slightly greater than that of water, enabling the soft manta ray robot 100 in S28 to dive under the influence of gravity.

[0121] By periodically inflating or deflating the four air chambers 213 within multiple cycles T by the control module 30, the state of the first actuator 22 and the second actuator 23 can be controlled, such as flapping upwards, horizontally, or downwards. The flapping angle of the first actuator 22 and the second actuator 23 can also be controlled, enabling the soft manta ray robot 100 to perform the first forward movement, the second forward movement, the third forward movement, the turning movement to the right, the turning movement to the left, the upward movement, and the diving movement, thus making the soft manta ray robot 100 more biomimetic to the movement of a real manta ray.

[0122] According to the driving method of the present invention, the inflation and deflation operations of each air chamber 213 by the control module 30 can adjust the inflation amount in each air chamber 213 to drive the soft manta ray robot 100 to move. The soft manta ray robot 100 has more degrees of freedom, higher biomimicry, and better mobility.

[0123] The following detailed description of a soft manta ray-like robot 100 according to a specific embodiment of the present invention is based on the accompanying drawings. It is to be understood that the following description is merely illustrative and should not be construed as limiting the invention.

[0124] like Figures 3-12 As shown, the soft manta ray-inspired robot 100 includes a torso 10, two pectoral fins 20, and a control module 30. The torso 10 is provided with a torso skeleton 11. The two pectoral fins 20 are located on both sides of the torso 10 along the span F1 direction. The two pectoral fins 20 are provided with connected pneumatic actuators 21 and flexible fin surfaces 24. The pneumatic actuators 21 are located on the front side of the flexible fin surfaces 24.

[0125] The pneumatic actuator 21 includes a first actuator 22 and a second actuator 23. The first actuator 22 is located on the left pectoral fin 20, and the second actuator 23 is located on the right pectoral fin 20. Both the first actuator 22 and the second actuator 23 include an actuator frame 211 and four pneumatic membranes 212 arranged in the vertical direction F2. The left pectoral fin 20 includes the first actuator 22 connected and located on the front side and a flexible fin surface 24 located on the rear side, and the right pectoral fin 20 includes the second actuator 23 connected and located on the front side and a flexible fin surface 24 located on the rear side.

[0126] At the first actuator 22 or the second actuator 23, two pneumatic diaphragms 212 are disposed on the upper side of the actuator frame 211, and two other pneumatic diaphragms are disposed on the lower side of the actuator frame 211. An air chamber 213 is formed between the two pneumatic diaphragms 212 on the upper side of the actuator frame 211, and an air chamber 213 is formed between the two pneumatic diaphragms 212 on the lower side of the actuator frame 211. Thus, both the first actuator 22 and the second actuator 23 are provided with two air chambers 213, and the entire pneumatic actuator 21 is provided with four air chambers 213.

[0127] The pneumatic actuator 21 has four air vents 215 that correspond one-to-one with the four air chambers 213, and the air vents 215 are located at the rear end of the pneumatic actuator 21. The air chambers 213 have multiple communicating air passages 214 that extend along the forward direction F3 of the soft manta ray robot 100.

[0128] The control module 30 is connected to the four air ports 215 of the pneumatic actuator 21 to periodically inflate or deflate the four air chambers 213, so that the pneumatic actuator 21 moves along the span F2 to drive the flexible fin surface 24 to make flexible undulation along the flow direction, thereby driving the soft manta ray robot 100 to perform the first forward movement, the second forward movement, the third forward movement, the third forward movement, the right-turning turning movement, the left-turning turning movement, the ascending movement, and the descending movement.

[0129] In the forward direction F3, the maximum size of the pectoral fin 20 is L1, the maximum size of the actuator skeleton 211 is L2, and the maximum size of the flexible fin surface 24 is L3. L2+L3=L1, L2<L1 / 2, L3>L1 / 2. The pneumatic actuator 21 actively drives the front pectoral fin 20 to flap, which in turn drives the rear flexible fin surface 24 to undulate, thus achieving semi-fin surface drive. The active-passive hybrid drive effect is good.

[0130] The soft manta ray-like robot 100 includes a support structure 50 and four films 40 arranged and connected in sequence along the vertical direction F2. The support structure 50 is a PVC sheet with a thickness of 0.4 mm, and the films 40 are TPU films with a thickness of 0.2 mm.

[0131] The support structure 50 includes a torso skeleton 11 and two actuator skeletons 211. The four membranes 40 include a first membrane 41, a second membrane 42, and two third membranes 43. The underwater portion of the soft manta ray-inspired robot 100 includes, from top to bottom, the second membrane 42, the first membrane 41, the support structure 50, the third membrane 43, and the third membrane 43. The torso 10 has a middle portion 401 of the second membrane 42, a middle portion 401 of the first membrane 41, a torso skeleton 11, a middle portion 401 of the third membrane 43, and a middle portion 401 of the third membrane 43, all stacked from top to bottom. The pectoral fins 20 have side portions 402 of the second membrane 42, side portions 402 of the first membrane 41, actuator skeletons 211, side portions 402 of the third membrane 43, and side portions 402 of the third membrane 43, all stacked from top to bottom. At the pectoral fin 20, the aerodynamic membrane 212 includes the front side of the two side portions 402 of the first membrane 41, the two side portions 402 of the second membrane 42, and the two side portions 402 of the third membrane 43, and the flexible fin surface 24 includes the rear side of the two side portions 402 of the first membrane 41.

[0132] Adjacent films 40 are thermoplastically connected and can form air chambers 213. The support structure 50 has multiple perforations 51, which are elongated holes extending through the support structure 50 in the vertical direction F2. The films 40 located on both sides of the perforations 51 in the vertical direction F2 are thermoplastically connected through the perforations 51. The soft manta ray-like robot 100 also includes a counterweight, which is located on the support structure to make the density of the soft manta ray-like robot slightly greater than that of water.

[0133] Under normal conditions, the soft manta ray-like robot 100 has a length of 170mm in the front-to-back direction, a wingspan of 300mm in the left-to-right direction, and a thickness of 1.2mm. The extremely thin thickness and near-planar two-dimensional structure of the soft manta ray-like robot 100 allow it to possess the flat, wide, and symmetrical geometric features of a real manta ray. The robot 100 roughly replicates and simplifies the outline of the real manta ray's body and wing-like pectoral fins, exhibiting a high degree of biomimicry.

[0134] The support structure 50 provides a certain rigidity to the entire soft manta ray-inspired robot 100, ensuring that its posture is not easily disturbed by water flow during its movement in the water. It also serves to fix the pectoral fin air chambers 213, acting as a fish skeleton, so that deformation at the air chambers 213 is less affected by water flow, allowing for high-quality completion of intended movements. The membrane 40 is flexible and can generate fish-like waves through fluid-structure interaction with the water.

[0135] In the process of manufacturing the soft manta ray-like robot 100, the support structure 50 and the film 40 are first pre-processed by laser cutting according to a preset shape, and a thermoplastic path 60 is pre-designed for each layer of film 40 for subsequent bonding. The two films 40 are bonded together by thermoplastic printing according to the preset thermoplastic path 60 to form an air chamber 213. The air chamber 213 includes multiple interconnected strip-shaped channels for communication with the control module 30. The support structure 50 has a hollowed-out portion 51. The films 40 on both sides of the support structure 50 along the vertical direction are bonded together at the hollowed-out portion 51 by thermoplastic printing to embed the support structure 50 between the two films 40.

[0136] In the soft manta ray-inspired robot 100, when the air chamber 213 is inflated, it expands, causing the pneumatic actuator 21 to bend and deform, flapping upwards or downwards. When the air chamber 213 is deflated, it returns to a horizontal position. Periodic inflation and deflation of the air chamber 213 enables the pneumatic actuator 21 to complete a bending-flapping-returning-to-horizontal-flapping cycle. When the pneumatic actuator 21 flaps, it drives the flexible fin surface 24 to form flexible ripples along the flow direction, interacting with the water to form a backward-propagating fish-body wave, generating thrust and providing propulsion for the various movements of the soft manta ray-inspired robot 100.

[0137] The soft manta ray-inspired robot 100 has a relatively simple internal structure. The design reduces the volume and weight of the water-entry portion, improving its mobility. The control module 30 includes a control source electrical device 31 and a flexible hose 32. The control source electrical device 31 includes an air source, a valve body, and an air pump. The control source electrical device 31 is connected to the air chamber 213 via the flexible hose 32. By placing the control source electrical device 31, which inflates or deflates the soft manta ray-inspired robot 100, in a terrestrial environment, and connecting it to the water-entry portion of the robot 100 via the flexible hose 32, the waterproofing problem of the control source electrical device 31 in related technologies is solved.

[0138] The control source electrical device 31 includes one or more control components (such as an STM32 microcontroller, Raspberry Pi, Arduino, serial communication module, and power amplifier), valve bodies (such as solenoid valves), and an air pump. Specifically, the control components include an adjustable DC regulated power supply, a computer, an STM32 microcontroller, a USB serial communication module, and a power amplifier, and the valve body includes four solenoid valves and a busbar for integrating the four solenoid valves.

[0139] The STM32 microcontroller used is the STM32F103RCT6 (a model of STM32 microcontroller), which receives action program commands from the computer via the USB serial communication module and also sends PWM waves to control the opening and closing of the solenoid valve. The adjustable DC regulated power supply, using a TDA305, provides a rated operating voltage of 12V to the air pump and a 12V operating voltage to the PWM power amplifier circuit board.

[0140] The PWM power amplifier uses a YYNMOS-8, with an input PWM signal of 3-5V. Under a 12V supply voltage, it can amplify the PWM wave to a rated current of 10A. The air pump uses a GC14-80, with a flow rate of 14L / min, operating at a rated voltage of 12V, to supply air to the solenoid valve.

[0141] The solenoid valves are G-type DC12V two-position three-way solenoid valves. Four solenoid valves are connected to the fish's air chamber 213 via transparent silicone tubes. The solenoid valves receive amplified PWM signals and open and close regularly under the control of the PWM signals, regulating the inflation and deflation of the air chamber 213. A 4F manifold is used to integrate and distribute the air supply from the air pump to the various secondary valves of the solenoid valves, supporting the operation of multiple valves simultaneously.

[0142] The solenoid valve is a 2-position 3-way type. One end of the solenoid valve is connected to an air pump for air intake, and the other end is connected to the air vent 215 of the bionic manta ray robot for inflating or deflating the air chamber 213. The STM32 microcontroller is connected to the computer via a USB serial communication module, which can send action program commands to the STM32 microcontroller. The STM32 microcontroller generates a corresponding PWM wave (pulse width modulation signal) according to the command, and the signal is amplified by the PWM power amplifier to control the opening and closing of the solenoid valve.

[0143] During operation, the soft manta ray-inspired robot 100 continuously supplies or extracts air to the solenoid valves at a constant power. By adjusting the output PWM wave, the periodic closing of each solenoid valve can be controlled, thereby periodically filling and deflating each air chamber 213 to achieve the preset action.

[0144] This application utilizes a combination of flapping movements from the left and right pectoral fins (20 in total) to achieve over 100 different forward movement modes, different turning directions, and ascent and descent motion modes for the soft manta ray-inspired robot. A schematic diagram of the control program for the control source electrical device 31 is shown below. Figure 11 As shown.

[0145] For either the left or right side of the pectoral fin 20, the upper and lower air chambers 213 are inflated or deflated to keep the pectoral fin 20 in a horizontal position. When the upper air chamber 213 is inflated and the lower air chamber 213 is deflated, the pectoral fin 20 bends upward. When the lower air chamber 213 is inflated and the upper air chamber 213 is deflated, the pectoral fin 20 bends downward.

[0146] By controlling the periodic inflation or deflation of the upper and lower air chambers 213 on either side of the left or right, the corresponding pectoral fin 20 can be kept in a horizontal position. For example, controlling the two air chambers 213 on the left side to inflate them simultaneously will keep the left pectoral fin 20 horizontal. Conversely, controlling the two air chambers 213 on the left side to deflate them simultaneously will keep the left pectoral fin 20 horizontal. When the upper and lower air chambers 213 on either side of the left or right are simultaneously inflated, the pneumatic actuator 21 corresponding to the pectoral fin 20 on that side is in tension mode, exhibiting greater stiffness.

[0147] Based on this, the orderly inflation and deflation of the air chamber 213 can be controlled by the control source electrical equipment 31, so that the pneumatic actuator 21 can beat in an orderly manner, and the pectoral fin 20 can perform a variety of actions, enabling the soft manta ray-like robot 100 to complete a variety of movements.

[0148] The following describes the driving method for the motion of the manta ray-inspired robot 100 using the driving software of this application.

[0149] First, the three inflation / deflation states of the air chamber 213 are defined. The amount of gas in the air chamber 213 is denoted as V1. The maximum inflation amount that prevents damage to the air chamber 213 is a predetermined amount of gas, denoted as V2. When V1 = V2, the air chamber 213 is in a fully inflated state; when 0 < V1 < V2, the air chamber 213 is in a partially inflated state; when V1 = 0, the air chamber 213 is in a completely deflated state.

[0150] The driving methods include:

[0151] S1: The control module 30 periodically inflates or deflates the four air chambers 213 within multiple cycles T, so that the air chambers 213 are in a fully inflated state, a deflated state, or a partially inflated state, thereby driving the soft manta ray-like robot 100 to move.

[0152] The soft manta ray-like robot 100 moves within each cycle T as follows (steps S21, S22, S23, S24, S25, S26, S27 and S28), with each cycle denoted as T.

[0153] In step S1, any one of steps S21, S22, S23, S24, S25, S26, S27 and S28 is selected and repeated to realize various movements of the soft manta ray robot 100.

[0154] S21: Within 0 to 0.5T, the control module 30 keeps the upper left and upper right air chambers 213 fully inflated and the lower left and lower right air chambers 213 deflated, while the first actuator 22 and the second actuator 23 move upwards. Within 0.5T to T, the control module 30 keeps the upper left and upper right air chambers 213 deflated and the lower left and lower right air chambers 213 fully inflated, while the first actuator 22 and the second actuator 23 move downwards. These actions drive the soft manta ray-like robot 100 to perform a first forward movement of symmetrical up-and-down flapping motion.

[0155] Specifically, for example, in a cycle T of 450ms, within 0-225ms, the solenoid valves controlling the upper left and upper right air chambers 213 are fully open, inflating them rapidly until they are fully inflated, and then the solenoid valves are closed. Similarly, the solenoid valves controlling the lower left and lower right air chambers 213 are fully open, deflating them until they are completely deflated, and then the solenoid valves are closed. Within 0-225ms, the pectoral fins 20 on both sides flap upwards. Within 225ms-450ms, the same process is repeated: the upper left and upper right air chambers 213 are completely deflated, and the lower left and lower right air chambers 213 are rapidly inflated. Within 225ms-450ms, the pectoral fins 20 on both sides flap downwards.

[0156] The second cycle T is the same as the first cycle T. Repeating this cycle multiple times, the upper air chamber 213 is inflated while the lower air chamber 213 is deflated, and vice versa. This causes the pectoral fins 20 on both sides to flap upwards, downwards, and upwards again, thus enabling the soft manta ray-like robot 100 to perform periodic upward and downward flapping movements with consistent amplitude. At this time, the soft manta ray-like robot 100 can achieve relatively fast forward movement.

[0157] S22: Within 0 to 0.45T, the control module 30 keeps the upper left and upper right air chambers 213 fully inflated and the lower left and lower right air chambers 213 deflated, while the first actuator 22 and the second actuator 23 move upwards. Within 0.45T to 0.9T, the control module 30 keeps the upper left and upper right air chambers 213 deflated and the lower left and lower right air chambers 213 fully inflated, while the first actuator 22 and the second actuator 23 move downwards. Within 0.9T to T, the control module 30 keeps all four air chambers 213 deflated and the first actuator 22 and the second actuator 23 horizontal. These actions drive the soft manta ray-like robot 100 to perform a second forward motion of sequential up-and-down symmetrical flapping and gliding within a cycle.

[0158] Specifically, for example, if a cycle T is 500ms, within 0-225ms, similarly, the upper left and upper right air chambers 213 are rapidly filled with air, while the lower left and lower right air chambers 213 are deflated. Therefore, within 0-225ms, the pectoral fins 20 on both sides flap upwards. Within 225ms-450ms, the upper left and upper right air chambers 213 are deflated, while the lower left and lower right air chambers 213 are rapidly filled with air. Therefore, within 225ms-450ms, the pectoral fins 20 on both sides flap downwards. Within 450ms-500ms, all four air chambers 213 are deflated, and within 450ms-500ms, the pectoral fins 20 on both sides quickly return to a horizontal position. Therefore, within 450ms to 500ms, the soft manta ray-like robot 100 performs gliding motions. The second cycle T is the same operation as the first cycle T, and multiple cycles T are repeated, which enables the pectoral fins 20 on both sides to flap upwards, flap downwards, glide, flap upwards again, etc., thereby enabling the soft manta ray-like robot 100 to achieve periodic upward flapping, downward flapping, and gliding.

[0159] S23: Within 0 to 0.5T, the control module 30 keeps the upper left and upper right air chambers 213 partially inflated and the lower left and lower right air chambers 213 fully deflated. The first actuator 22 and the second actuator 23 move upwards with a bending angle smaller than that in the fully inflated state. Within 0.5T to T, the control module 30 keeps the upper left and upper right air chambers 213 fully deflated and the lower left and lower right air chambers 213 fully inflated. The first actuator 22 and the second actuator 23 move downwards. These actions drive the soft manta ray-like robot 100 to perform a third forward movement of asymmetrical up-and-down flapping.

[0160] Specifically, for example, if a cycle T is 450ms, within the range of 0-225ms, by adjusting the duty cycle of the PWM wave output or using other means, the duty cycle of the PWM wave is made only 1% when the upper left and upper right air chambers 213 are inflated. This reduces the opening of the solenoid valves controlling the upper left and upper right air chambers 213, causing them to inflate slowly and partially. Then, the solenoid valves are closed. Conversely, the solenoid valves controlling the lower left and lower right air chambers 213 are opened to their maximum extent, fully opening, to de-inflate them completely. Then, the solenoid valves are closed. Therefore, within the range of 0-225ms, the pectoral fins 20 on both sides flap upwards with a small amplitude. Within 225ms to 450ms, the solenoid valves controlling the upper left and upper right air chambers 213 are fully open, deflating them completely. The solenoid valves controlling the lower left and lower right air chambers 213 are also fully open, rapidly inflating them. Therefore, within 225ms to 450ms, the pectoral fins 20 on both sides flap downwards with a large amplitude.

[0161] The second cycle T is the same as the first cycle T. Repeating this cycle multiple times, the upper air chamber 213 is slowly inflated while the lower air chamber 213 is deflated, and the upper air chamber 213 is deflated while the lower air chamber 213 is quickly inflated. This allows the pectoral fins 20 on both sides to flap upwards with a small amplitude, downwards with a large amplitude, upwards with a small amplitude, and so on. This enables the soft manta ray-like robot 100 to perform periodic upward and downward flapping movements with inconsistent amplitudes.

[0162] Besides adjusting the duty cycle of the PWM wave output to adjust the opening of the solenoid valve and thus regulate the amplitude of the pectoral fin 20's flapping motion, the amplitude of the pectoral fin 20's flapping motion can also be adjusted by regulating the air pressure of the air pump. Furthermore, the frequency and amplitude of the pectoral fin 20's flapping motion can be adjusted by regulating the inflation and deflation time, thereby achieving the adjustment of the movement speed of the soft manta ray-inspired robot 100. Among these, an inflation / deflation time of 225ms and a PWM wave output duty cycle of 1% during slow inflation are optimal parameters obtained from multiple experiments, which effectively achieve the corresponding movements.

[0163] S24: Within 0 to 0.5T, the control module 30 ensures all four air chambers 213 are fully deflated, and the first actuator 22 and the second actuator 23 are horizontal. Within 0.5T to T, the control module 30 ensures the upper left and upper right air chambers 213 are fully deflated, and the lower left and lower right air chambers 213 are fully inflated, causing the first actuator 22 and the second actuator 23 to flap downwards. These actions drive the soft manta ray-like robot 100 to perform a fourth forward movement of flapping downwards.

[0164] Specifically, for example, a cycle T is 450ms. Similarly, the upper left and upper right air chambers 213 are always in a deflated state from 0 to 450ms, while the lower left and lower right air chambers 213 are in a deflated state from 0 to 225ms and in a fully inflated state from 225ms to 450ms. The second cycle T is the same as the first cycle T, and multiple cycles T are repeated, causing the left and right pectoral fins 20 to cyclically perform horizontal, downward, horizontal, downward, and so on. Within each cycle T, only the upper or lower air chamber 213 is cyclically inflated and deflated, while the other side remains deflated. This allows for downward or upward slapping movements, enabling the soft manta ray-like robot 100 to achieve relatively slow forward movement.

[0165] Experimental calculations show that the speeds of the four forward movement modes can be ranked from highest to lowest as follows: Third forward movement mode > Second forward movement mode > First forward movement mode > Fourth forward movement mode.

[0166] S25: Within 0 to 0.5T, the control module 30 deflates the upper left air chamber 213, while filling the lower left, upper right, and lower right air chambers 213. The first actuator 22 moves downwards, and the second actuator 23 moves horizontally. Within 0.5T to T, the control module 30 deflates all four air chambers 213, and the first and second actuators 22 and 23 move horizontally. These actions drive the soft manta ray-like robot 100 to turn to the right.

[0167] Specifically, for example, if one cycle T is 450ms, similarly, the upper left air chamber 213 is always in a deflated state from 0 to 450ms, while the lower left air chamber 213 and the two right air chambers 213 are in a fully inflated state from 0 to 225ms and in a deflated state from 225ms to 450ms. The second cycle T is the same operation as the first cycle T, and this cycle is repeated multiple times, causing the left pectoral fin 20 to cyclically flap downwards, horizontally, downwards again, etc., while the right pectoral fin 20 cyclically expands, contracts, expands again, etc., while the right pectoral fin 20 remains in a horizontal state, causing the soft manta ray-like robot 100 to turn to the right.

[0168] S26: Within 0 to 0.5T, the control module 30 deflates the upper right air chamber 213, while filling the upper left, lower left, and lower right air chambers 213. The first actuator 22 is horizontal, and the second actuator 23 moves downwards. Within 0.5T to T, the control module 30 deflates all four air chambers 213, and the first and second actuators 22 are horizontal. These actions drive the soft manta ray-like robot 100 to turn to the left.

[0169] Specifically, for example, if one cycle T is 450ms, similarly, the upper right air chamber 213 is always in a deflated state from 0 to 450ms, while the lower right air chamber 213 and the two left air chambers 213 are in a fully inflated state from 0 to 225ms and in a deflated state from 225ms to 450ms. The second cycle T is the same operation as the first cycle T, and multiple cycles T are repeated, causing the right pectoral fin 20 to cyclically flap downwards, horizontally, and downwards again, while the left pectoral fin 20 cyclically expands, contracts, and expands again, while the left pectoral fin 20 remains horizontal, causing the soft manta ray-like robot 100 to turn to the left.

[0170] S27: The control module 30 inflates the four air chambers 213, so that all four air chambers 213 are in a fully inflated state. The first driver 22 and the second driver 23 are horizontal, driving the soft manta ray robot 100 to move upward.

[0171] S28: The control module 30 releases air from the four air chambers 213, so that all four air chambers 213 are in a fully deflated state. The first driver 22 and the second driver 23 are horizontal, driving the soft manta ray robot 100 to dive.

[0172] A 2g counterweight is attached to the surface of the soft manta ray-inspired robot 100, making its overall weight slightly greater than the buoyancy it experiences when all its air chambers 213 are deflated. This allows the soft manta ray-inspired robot 100 to dive underwater. Conversely, when all air chambers 213 are fully inflated, the volume of the air chambers changes, causing the buoyancy of the soft manta ray-inspired robot 100 to be slightly greater than its own weight, enabling the underwater portion of the soft manta ray-inspired robot 100 to ascend.

[0173] In this specific embodiment, the soft manta ray-like robot 100 has a mass of 27.2g, a maximum forward speed of 0.79BL / s (body length per second), a maximum turning speed of 7° / s, and a maximum turning radius of 2BL.

[0174] This application uses the manta ray as a biomimetic model and designs a soft manta ray-inspired robot 100 based on a thin-film pneumatic drive method (bending deformation of the pneumatic actuator 21). Through motion control algorithms, it achieves multiple motion modes such as forward movement, turning, ascending, and diving. Compared with rigidly driven biomimetic manta rays in related technologies, this invention has advantages such as high biomimicry, strong maneuverability, and low operating noise; compared with flexibly driven biomimetic manta rays in related technologies, this invention has advantages such as high propulsion efficiency, simplified structure, low manufacturing difficulty, and low manufacturing cost.

[0175] This invention is based on a novel pneumatic actuator 21, and for the first time applies this flexible pneumatic actuation method to a manta ray-inspired robot, providing more possibilities for the design of flexible-driven manta ray-inspired robots. Furthermore, the manta ray-inspired robot manufactured by this invention has advantages such as lightweight design, strong stealth capabilities, and low noise, contributing new research methods to fields such as underwater exploration, marine biology research, and coastal ecosystem monitoring.

[0176] Other configurations and operations of the soft manta ray robot 100 and its driving method according to embodiments of the present invention are known to those skilled in the art and will not be described in detail here.

[0177] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0178] In the description of this specification, the references to terms such as "embodiment," "specific embodiment," and "example" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0179] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A soft manta ray robot based on thin film pneumatic actuators, characterized in that, include: Torso, wherein the torso is provided with a torso skeleton; Two pectoral fins are located on both sides of the trunk along the span of the body. Each pectoral fin is equipped with a pneumatic actuator, which includes a first actuator and a second actuator located on the two pectoral fins respectively. Both the first actuator and the second actuator include an actuator skeleton and four pneumatic membranes arranged in the vertical direction. Both actuator skeletons are connected to the trunk skeleton. At each pectoral fin, two pneumatic membranes are located on the upper side of the actuator skeleton and two other pneumatic membranes are located on the lower side of the actuator skeleton. An air chamber is formed between two pneumatic membranes on either side of the actuator skeleton in the vertical direction. The control module is connected to the four air chambers of the pneumatic actuator to periodically inflate or deflate the four air chambers, thereby realizing the pneumatic flapping of the pneumatic actuator to drive the soft manta ray-like robot to move. The movement includes at least forward movement, turning, rising and diving. The first actuator is located to the left of the second actuator. The first actuator includes an upper left air chamber and a lower left air chamber arranged in the vertical direction. The second actuator includes an upper right air chamber and a lower right air chamber arranged in the vertical direction. When the gas volume V1 in the air chamber is equal to the predetermined gas volume V2, the air chamber is in a fully filled state. In the state where 0 < V1 < V2, the air chamber is in a partially inflated state; in the state where V1 = 0, the air chamber is in a fully deflated state. The driving method includes: The control module periodically inflates or deflates the four air chambers within multiple cycles, placing the air chambers in a fully inflated state, a deflated state, or a partially inflated state, thereby driving the soft manta ray-like robot to move. The movement of the soft manta ray-like robot in each cycle is as follows, and each cycle is denoted as T. Within 0~0.5T, the control module keeps the upper left and upper right air chambers in a fully inflated state, and the lower left and lower right air chambers in a deflated state, while the first and second actuators move upwards; within 0.5T~T, the control module keeps the upper left and upper right air chambers in a deflated state, and the lower left and lower right air chambers in a fully inflated state, while the first and second actuators move downwards; these actions drive the soft manta ray-like robot to perform a first forward motion of symmetrical up-and-down flapping; or... Within 0~0.45T, the control module keeps the upper left and upper right air chambers in a fully inflated state, and the lower left and lower right air chambers in a deflated state, while the first and second actuators move upwards; within 0.45T~0.9T, the control module keeps the upper left and upper right air chambers in a deflated state, and the lower left and lower right air chambers in a fully inflated state, while the first and second actuators move downwards; within 0.9T~T, the control module keeps all four air chambers in a deflated state, and the first and second actuators move horizontally; these actions drive the soft manta ray-like robot to perform a second forward motion of sequential up-and-down symmetrical flapping and gliding within a cycle; or... Within 0~0.5T, the control module keeps the upper left and upper right air chambers in a partially inflated state, and the lower left and lower right air chambers in a deflated state. The first and second actuators move upwards with a bending angle smaller than that in the fully inflated state. Within 0.5T~T, the control module keeps the upper left and upper right air chambers in a deflated state, and the lower left and lower right air chambers in a fully inflated state. The first and second actuators move downwards. These actions drive the soft manta ray-like robot to perform a third forward motion of asymmetrical up-and-down flapping. Or... Within 0~0.5T, the control module keeps all four air chambers in the deflated state, with the first and second actuators horizontal; within 0.5T~T, the control module keeps the upper left and upper right air chambers in the deflated state, and the lower left and lower right air chambers in the fully inflated state, with the first and second actuators flapping downwards; these actions drive the soft manta ray-like robot to perform a fourth forward movement of flapping downwards; or... Within 0~0.5T, the control module keeps the upper left air chamber in the deflated state, and the lower left, upper right, and lower right air chambers in the fully inflated state. The first actuator moves downwards, and the second actuator moves horizontally. Within 0.5T~T, the control module keeps all four air chambers in the deflated state, and the first and second actuators move horizontally. These actions drive the soft manta ray-like robot to make a rightward turning motion; or... Within 0~0.5T, the control module keeps the upper right air chamber in the deflated state, and the upper left, lower left, and lower right air chambers in the fully inflated state. The first actuator is horizontal, and the second actuator is pulsating downwards. Within 0.5T~T, the control module keeps all four air chambers in the deflated state, and the first and second actuators are horizontal. These actions drive the soft manta ray-like robot to make a leftward turning motion; or... The control module inflates the four air chambers, ensuring all four chambers are fully inflated. The first and second actuators are horizontal, driving the soft manta ray-like robot to ascend; or... The control module deflates the four air chambers, so that all four air chambers are in the deflated state. The first and second actuators are horizontal, driving the soft manta ray-like robot to dive.

2. The thin-film gas-dynamic driver based soft manta ray robot of claim 1, wherein, The pneumatic actuator has four air vents that correspond one-to-one with the four air chambers. The air vents are located at the rear end of the pneumatic actuator and are connected to the control module. Each air chamber has multiple interconnected air channels that extend along the forward direction of the soft manta ray-like robot.

3. The soft manta ray-inspired robot based on a thin-film pneumatic actuator according to claim 1, characterized in that, The pectoral fin is equipped with a connected pneumatic actuator and a flexible fin surface. The pneumatic actuator is located in front of the flexible fin surface. The pneumatic actuator generates a pneumatic flapping motion, which causes the flexible fin surface to generate flexible undulations to drive the soft manta ray-like robot to move.

4. The soft manta ray-inspired robot based on a thin-film pneumatic actuator according to claim 3, characterized in that, In the forward direction, the maximum size of the pectoral fin is L1, the maximum size of the actuator skeleton is L2, the maximum size of the flexible fin surface is L3, L2+L3=L1, L2<L1 / 2, L3>L1 / 2.

5. The soft manta ray-inspired robot based on a thin-film pneumatic actuator according to claim 3, characterized in that, The soft manta ray-like robot has multiple films connected sequentially in a vertical direction. The multiple films include a first film, the middle portion of which covers the torso skeleton and the side portions of which cover the two pectoral fins. The side portions of the first film include areas covering the actuator skeleton and areas forming the flexible fin surfaces.

6. The soft manta ray-inspired robot based on a thin-film pneumatic actuator according to claim 5, characterized in that, The plurality of films also include a second film and two third films, wherein the middle portion of the second film covers a portion of the torso skeleton and the side portions cover the actuator skeleton, and the middle portion of the third film covers the torso skeleton and the side portions cover the actuator skeleton. The soft manta ray-like robot includes a support structure, which includes the connected torso skeleton and two actuator skeletons. The first membrane and the second membrane are located on the upper side of the support structure, the second membrane is located on the upper side of the first membrane, and the two third membranes are located on the lower side of the support structure.

7. The soft manta ray-inspired robot based on a thin-film pneumatic actuator according to claim 5, characterized in that, The adjacent films are thermoplastically connected and adapted to form the air chamber.

8. The soft manta ray-inspired robot based on a thin-film pneumatic actuator according to claim 7, characterized in that, The soft manta ray-like robot includes a support structure, which includes the connected torso skeleton and two actuator skeletons. The support structure has multiple hollow sections, which are elongated holes that penetrate the support structure in the vertical direction. The films located on both sides of the hollow sections in the vertical direction are thermoplastically connected through the hollow sections.

9. The soft manta ray-inspired robot based on a thin-film pneumatic actuator according to any one of claims 1-8, characterized in that, The soft manta ray-like robot includes a support structure and a counterweight. The support structure includes the connected torso skeleton and two actuator skeletons. The counterweight is located on the support structure, making the density of the soft manta ray-like robot greater than the density of water.

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