Configurable mesh structure pneumatic artificial muscle and functional device

Abstract

The application relates to the field of soft robot pneumatic artificial muscles, and provides a configurable grid structure pneumatic artificial muscle and a functional device, which comprises one or more array structures, each array structure comprises a plurality of grid units connected together, each grid unit comprises an active air cavity and a passive connecting layer discontinuously connected with the active air cavity; the array structure has an initial state and a final state; when the array structure in the initial state is positively excited, the active air cavity in the array structure is expanded and stretched, thereby driving the passive connecting layer to adaptively deform, so that the array structure generates horizontal stretching movement and vertical contraction movement, until the array structure reaches the final state. By adopting the positive pressure contraction configurable grid-shaped pneumatic artificial muscle, the positive pressure contraction pneumatic artificial muscle with high contraction rate and high output force is realized, the configurability is good, and the advantages of light weight, low cost, good flexibility and excellent comprehensive performance are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of soft robotic pneumatic artificial muscle, in particular, to a configurable grid structure pneumatic artificial muscle and functional device, and more particularly to a configurable grid structure pneumatic artificial muscle with high contraction rate and high output force. BACKGROUND

[0002] The pneumatic artificial muscle composed of soft material or flexible material is more compliant in driving than the traditional motor and air cylinder, and thus has great application prospect in building mechanical systems (such as bionic robots, soft exoskeletons and flexible grippers) for human-friendly interaction.

[0003] At present, the pneumatic artificial muscle can be divided into two categories: positive pressure driving and negative pressure driving. The positive pressure driving pneumatic artificial muscle mainly includes Mckibben type, Pouch type and their variants. Although these artificial muscles can generate a larger blocking force, the maximum contraction rate they can achieve is small; it is difficult to maintain high output force in a high contraction rate working state; the configuration and driving mode are single, and the configurability is insufficient. The negative pressure driving pneumatic artificial muscle can achieve high contraction rate and excellent configurability, but the driving pressure of negative pressure is usually less than one atmosphere, which limits the mechanical performance of the negative pressure pneumatic artificial muscle. Therefore, it is of great significance to design a positive pressure driving pneumatic artificial muscle with high contraction rate, high output force and excellent configurability based on a new structure. SUMMARY

[0004] In view of the defects in the prior art, the purpose of the present application is to provide a configurable grid structure pneumatic artificial muscle and functional device.

[0005] According to the present application, a configurable grid structure pneumatic artificial muscle is provided, which comprises one or more array structures, each of which comprises a plurality of grid units connected together, each of which comprises an active air cavity and a passive connection layer discontinuously connected with the active air cavity.

[0006] The array structure has an initial state and a final state. When the array structure in the initial state is excited by positive pressure, the active air cavity in the array structure can be expanded and straightened, thereby driving the passive connection layer to adaptively deform and generate horizontal elongation movement and vertical contraction movement due to the expansion and straightening, and finally making the array structure in the final state.

[0007] Preferably, the active air cavity is a closed cavity formed by the edge connection of an air cavity upper layer composite film and an air cavity lower layer composite film arranged in a matched shape and facing each other.

[0008] Preferably, the upper-layer composite film and the lower-layer composite film of the air cavity are connected by heat pressing and melting, and the heat pressing and melting of the air cavity upper-layer composite film and the air cavity lower-layer composite film is achieved by the solder resist layer with a set edge width.

[0009] Preferably, the air cavity upper-layer composite film and the air cavity lower-layer composite film are both TPU double-coated woven fabric, and the solder resist layer is silicone paper.

[0010] Preferably, the passive connection layer is a composite film with a zigzag structure, and each two adjacent zigzags are connected by an inner concave arc, and the passive connection layer is a TPU double-coated woven fabric.

[0011] Preferably, the width of the active air cavity and the length of the grid cell can be adjusted to match the maximum shrinkage rate of different requirements.

[0012] Preferably, the array structure is formed by connecting a plurality of vertical grid structures from left to right, and the vertical grid structure is formed by connecting the active air cavity, the passive connection layer, the active air cavity, the passive connection layer, and so on from top to bottom.

[0013] Preferably, the air cavity upper-layer composite film is provided with an air nozzle, and all the air nozzles of the array structure are connected and driven by the same air source.

[0014] Preferably, the air nozzle is made of TPU material and is connected to the air cavity upper-layer composite film by viscous cyanoacrylate adhesive or heat pressing.

[0015] According to the present application, a functional device is provided, which comprises the configurable grid structure pneumatic artificial muscle.

[0016] Compared with the prior art, the present application has the following beneficial effects:

[0017] 1. The present application creatively proposes an integrated flexible grid structure and air pressure driving method, designs a positive pressure shrinkage configurable grid-shaped pneumatic artificial muscle, and realizes a positive pressure shrinkage pneumatic artificial muscle with high shrinkage rate and high output force, and the maximum shrinkage rate can be adjusted by the ratio of the active air cavity width and the diamond cell length, and the adjustment range is 0%-100% open interval.

[0018] 2、The present application improves the configurability and versatility of the pneumatic artificial muscle. The geometry of the active air cavity and the passive connection layer in the component part can be changed, which changes the planar grid structure of the artificial muscle into the desired out-of-plane grid structure, thereby generating varying configurations and movements; the number of grid units in each row and each column can be adjusted according to actual application, and the artificial muscle has good versatility. The pneumatic artificial muscle is designed and manufactured by using a film material covered with a thermoplastic material, and has the advantages of light weight, low cost, good flexibility and excellent comprehensive performance. BRIEF DESCRIPTION OF DRAWINGS

[0019] Other features, objects and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments, made with reference to the following drawings:

[0020] Figure 1 is a structural schematic diagram of the array structure in the intermediate state;

[0021] Figure 2 is a driving schematic diagram of the artificial muscle in an embodiment of the present application;

[0022] Figure 3 is a working principle diagram of the artificial muscle rhombus unit in an embodiment of the present application;

[0023] Figure 4 is a component and manufacturing process diagram of the active air cavity in an embodiment of the present application;

[0024] Figure 5 is a passive connection layer structure diagram in an embodiment of the present application;

[0025] Figure 6 is a manufacturing process diagram of the artificial muscle in an embodiment of the present application;

[0026] Figure 7 is a force-displacement relationship diagram of the artificial muscle under different air pressure excitations in an embodiment of the present application;

[0027] Figure 8 is a structural schematic diagram of the artificial muscle in an embodiment of the present application.

[0028] The drawings show:

[0029] Active air cavity 1;

[0030] Upper layer composite film 11 of the air cavity;

[0031] Air nozzle 12;

[0032] Solder resist layer 13;

[0033] Lower layer composite film 14 of the air cavity

[0034] Passive connection layer 2;

[0035] sawtooth shape feature 21;

[0036] upper active cavity connection area 22;

[0037] upper active cavity connection area 23

[0038] semicircular active air cavity 101

[0039] semicircular passive connection layer 201 DETAILED DESCRIPTION

[0040] The application will be described in detail below with specific embodiments. The following examples will help those skilled in the art to further understand the application, but do not limit the application in any form. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of changes and improvements can be made. These are within the scope of the present application.

[0041] Example 1:

[0042] The application also provides a configurable grid structure pneumatic artificial muscle, comprising one or more array structures, each array structure comprising a plurality of connected grid cells, each grid cell comprising an active air cavity 1 and a passive connection layer 2 connected discontinuously with the active air cavity 1, the array structure having an initial state and a final state, when the array structure in the initial state is excited by positive pressure, the active air cavity 1 in the array structure will expand and straighten, thereby driving the passive connection layer 2 to adaptively deform, and due to the expansion, the array structure will produce horizontal extension movement and vertical contraction movement, until the array structure reaches the final state. It should be noted that the present application shortens the entire vertical length from the initial state to the final state, and in fact, through the positive pressure excitation, the entire pneumatic artificial muscle is contracted to realize the corresponding driving function.

[0043] The array structure is formed by connecting a plurality of vertical grid structures from left to right, and the vertical grid structure is formed in the connection form of active air cavity 1, passive connection layer 2, active air cavity 1, passive connection layer 2, …, active air cavity 1, passive connection layer 2 from top to bottom.

[0044] Specifically, the active air cavity 1 is a closed cavity formed by the edge connection of the air cavity upper layer composite film 11 and the air cavity lower layer composite film 14 arranged in a matched shape and opposite to each other, and when the array structure is in a final state, the active air cavity 1 expands to have a circular or elliptical structure in cross section, and the air cavity upper layer composite film 11 and the air cavity lower layer composite film 14 are edge-connected by a hot-pressing fusion mode, and in the hot-pressing fusion process, the air cavity upper layer composite film 11 and the air cavity lower layer composite film 14 are hot-pressed and fused at a set edge width through the solder resist layer 13. The air cavity upper layer composite film 11 and the air cavity lower layer composite film 14 are preferably TPU double-sided film-coated woven fabric, and the TPU double-sided film-coated woven fabric has thermoplastic TPU that can realize reliable connection between the film fabrics under a hot-pressing process, and the woven fabric can provide excellent strength. The solder resist layer 13 is preferably a silicone oil paper, which has the characteristic of not being bonded with TPU in a molten state, and by arranging the solder resist layer 13 between the air cavity upper layer composite film 11 and the air cavity lower layer composite film 14, the undesired connection between the film fabrics during processing can be effectively prevented, and the gas circulation is strengthened, that is, the parts between the air cavity upper layer composite film 11 and the air cavity lower layer composite film 14 that do not need to be fused are separated by the solder resist layer 13.

[0045] The passive connection layer 2 is a composite film in a sawtooth structure and is made of TPU double-sided film-coated woven fabric. Each two adjacent sawteeth are transitioned by an inner concave arc, and the passive connection layer 2 includes an upper active cavity connection area, a lower active cavity connection area, and a remaining area, and the sawtooth shape feature is used to adapt to the deformation of the active air cavity 1 in the grid structure under the action of gas pressure and reduce the internal force of the structure.

[0046] The air cavity upper layer composite film 11 is provided with an air nozzle 12, all the air nozzles 12 on the array structure are connected and driven by the same gas source. The air nozzle 12 can be hot-pressed or glued between the film, and the size and configuration are rich and have good toughness.

[0047] The application also provides a functional device including the configurable grid structure pneumatic artificial muscle, and the functional device can be applied to multiple fields, for example, the functional device is a robot, etc. The application realizes the pneumatic artificial muscle with high shrinkage, high output force, and multiple configurations by designing a flexible grid structure driver, and in addition, the pneumatic artificial muscle has the characteristics of light weight, low cost, and easy manufacturing, and can be widely applied to multiple fields.

[0048] This invention exhibits good compliance and high tensile strength in its natural state. Under positive pressure excitation, the active air chamber 1 expands and gradually straightens horizontally, while the mesh unit structure transforms the horizontal elongation motion into a vertical contraction motion. By adjusting the geometry of the active air chamber 1 and the passive connecting layer 2, the artificial muscle can be designed into other desired configurations, such as a semi-circular arch configuration. This invention, through the design of a flexible mesh structure actuator, realizes a pneumatic artificial muscle with high contraction rate, high output force, and multiple configurations. Furthermore, it is lightweight, low-cost, and easy to manufacture, making it widely applicable in robotics and medical fields.

[0049] Example 2:

[0050] This embodiment is a preferred example of Embodiment 1. Figures 1-8 As shown, this embodiment provides a configurable grid structure pneumatic artificial muscle with high contraction rate and high output force, including an array structure. In this embodiment, the array structure includes 15 grid units, forming three rows of vertical grid-like structures. Each vertical grid-like structure includes 5 pairs of active air chambers 1 and passive connecting layers 2, ultimately forming a grid structure of 3 columns and 5 rows of diamond-shaped unit arrays, as shown. Figure 2 , Figure 3 As shown, the leftmost side shows the structure of the artificial muscle in its initial state, and the rightmost side shows the structure of the artificial muscle in its final state. The positive pressure excitation of the artificial muscle causes the load to change position following the deformation of the artificial muscle.

[0051] In this embodiment, the functional device is a robot. A load is connected to the bottom of the array structure. The array structure shortens its vertical length through positive pressure excitation, thereby driving the load to perform corresponding movements. Figure 1 The diagram shows the structure of the robot in the intermediate state between the initial and final states. In the intermediate state, each grid cell has a diamond-shaped structure.

[0052] like Figure 4 As shown, the active air chamber 1 includes an upper composite film 11, an air nozzle 12, a solder resist layer 13, and a lower composite film 14. Both the upper and lower composite films 11 and 14 are made of TPU double-sided coated woven fabric and are the same size. The difference is that the upper composite film 11 has a small hole for mounting the air nozzle 12. One upper composite film 11 and one lower composite film 14 are aligned, and a solder resist layer 13, made of silicone paper, is placed between the two composite films. The solder resist layer 13 is smaller than both the upper and lower composite films 11 and 14; the smaller area is the heat-bonding area. A sealed air chamber is formed by melting the TPU through hot pressing and cooling the connection edges. The air nozzle 13 is made of TPU and is attached to the upper composite film 11 using a viscous cyanoacrylate adhesive.

[0053] Further, as shown in Figure 5 The passive connection layer 2 also adopts TPU double-sided film woven fabric, with a sawtooth shape feature 21, which includes the upper active cavity connection area 22, the lower active cavity connection area 23 and the remaining area, and the upper active cavity connection area 22 and the lower active cavity connection area 23 are staggered.

[0054] In the production of the pneumatic artificial muscle, 5 pairs of active air cavities 1 and passive connection layers 2 are folded in zigzag shape in advance, and then connected in the order of active air cavity-passive connection layer…active air cavity-passive connection layer, as shown in Figure 6 Each pair of active air cavity and passive connection layer is mirror connected to form a diamond grid structure, and the passive connection layer 2 is connected to the upper active cavity 4 times at the upper active cavity connection area 22 and connected to the lower active cavity 3 times at the lower active cavity connection area 23.

[0055] The pneumatic artificial muscle in this example can adjust the maximum contraction rate by the ratio of the active air cavity width and the side length of the diamond unit, and the adjustment range is an open interval of 0%-100%. As shown in Figure 7 The pneumatic artificial muscle in this basic example can maintain high output force in a high contraction rate state.

[0056] In this embodiment, the upper air cavity composite film 11, the solder mask layer 13, the lower air cavity composite film 14 and the passive connection layer 2 can be designed as needed by AutoCAD automatic software.

[0057] In this embodiment, the upper air cavity composite film 11, the solder mask layer 13, the lower air cavity composite film 14 and the passive connection layer can be cut by a laser cutting machine.

[0058] In this embodiment, the width of the narrowest part of the passive connection layer 2 should be appropriate to avoid too narrow causing insufficient tensile strength of the structure, while avoiding too wide to hinder the inflation deformation of the active air cavity 1.

[0059] In this embodiment, the air nozzle 13 can be directly bonded outside the upper air cavity composite film 11, or bonded from the inside to the outside of the upper air cavity composite film 11, leaving only the nozzle head outside.

[0060] It should be noted that the number of diamond grid units in each array structure is not limited, and can be flexibly set according to specific application scenarios to meet the needs of actual products. The active air cavity 1 and the passive connection layer 2 are not limited to straight line type long strips, as shown in Figure 8As shown, the semi-circular active air chamber 101 and the semi-circular passive connecting layer 201 can also be connected to form a pneumatic artificial muscle with a curved grid structure. Therefore, the shape, logarithm, and connecting area of ​​the active air chamber 1 and the passive connecting layer 2 can be varied and combined according to actual application scenarios to meet specific needs.

[0061] The working principle of this invention is as follows:

[0062] Configurable mesh-like pneumatic artificial muscles, in their uninflated, natural state, exhibit good flexibility and high tensile strength, achieving their maximum achievable length with relatively low preload. Figure 2 , Figure 3 In the initial state; under positive pressure excitation, compressed air enters each active air chamber 1 through the air nozzle 13, the active air chamber 1 expands, gradually straightening horizontally from a zigzag folded state, driving the passive connecting layer 2 to move and deform. The grid unit structure of the artificial muscle transforms the horizontal elongation motion into a vertical contraction motion, gradually entering the intermediate state and the final state. The serrated shape feature 21 of the passive connecting layer 2 is conducive to adapting to the deformation of the active air chamber 1 in the structure, reducing the internal forces of the structure, and increasing the structural stability.

[0063] The maximum contraction rate of the configurable grid-like pneumatic artificial muscle in this invention depends on the ratio of the width of the active air chamber to the side length of the rhomboid unit. Since the two are independent variables, the maximum contraction rate can be designed within the open range of 0%-100%.

[0064] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application 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 application.

[0065] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A configurable grid structure pneumatic artificial muscle, characterized in that, It includes one or more array structures, each array structure including multiple grid cells connected together, each grid cell including an active air chamber (1) and a passive connection layer (2) discontinuously connected to the active air chamber (1). The array structure has an initial state and a final state. When the array structure in the initial state is subjected to positive pressure excitation, the active air chamber (1) in the array structure can expand and straighten, thereby driving the passive connecting layer (2) to adaptively deform. Due to the expansion and straightening, the array structure generates horizontal elongation and vertical contraction movements, and finally the array structure is in the final state. The maximum contraction rate of the pneumatic artificial muscle is adjusted by the ratio of the width of the active air chamber to the side length of the rhomboid unit, and the adjustment range of the initial state and the final state is an open interval of 0%-100%. The active air chamber (1) is a sealed cavity formed by the edge connection of the upper composite film (11) and the lower composite film (14) of the air chamber, which are matched in shape and arranged opposite each other; The upper composite film (11) and the lower composite film (14) of the air cavity are connected by hot pressing and melting, wherein the upper composite film (11) and the lower composite film (14) of the air cavity are connected by hot pressing and melting with a set edge width through a solder resist layer (13). An air nozzle (12) is provided on the upper composite film (11) of the air cavity, and all the air nozzles (12) on the array structure are connected and driven by the same air source; The passive connection layer (2) is a composite film with a sawtooth structure. Each pair of adjacent sawtooths is transitioned by an inward concave arc. The passive connection layer (2) is made of TPU double-sided coated woven fabric.

2. The configurable mesh structure pneumatic artificial muscle according to claim 1, characterized in that, The upper composite film (11) and the lower composite film (14) of the air cavity are both made of TPU double-sided coated woven fabric, and the solder resist layer (13) is made of silicone paper.

3. The configurable mesh structure pneumatic artificial muscle according to claim 1, characterized in that, The ratio of the width of the active air chamber (1) to the side length of the grid cell can be adjusted to match the maximum shrinkage rate required for different needs.

4. The configurable mesh structure pneumatic artificial muscle according to claim 1, characterized in that, The array structure is formed by connecting multiple vertical grid structures from left to right. The vertical grid structure is formed from top to bottom in the form of active air chamber (1), passive connection layer (2), active air chamber (1), passive connection layer (2), ..., active air chamber (1), passive connection layer (2).

5. The configurable mesh structure pneumatic artificial muscle according to claim 1, characterized in that, The air nozzle (12) is made of TPU material and is attached to the upper composite film (11) of the air cavity by means of viscous cyanoacrylate adhesive or hot pressing.

6. A functional device, characterized in that, Includes the configurable mesh structure pneumatic artificial muscle as described in any one of claims 1 to 5.

Images