A modular and reconfigurable pneumatic soft robot

Abstract

The present invention provides a modular and reconfigurable pneumatic soft robot, which relates to the technical field of soft robots. It includes: a flexible outer shell, in which an airbag is placed. The airbag is fixedly connected with a T-shaped nylon washer, the T-shaped nylon washer is fixedly connected with a first flexible conduit, the other end of the first flexible conduit is fixedly connected with a pneumatic three-way joint, and the other interfaces of the pneumatic three-way joint are fixedly connected with second flexible conduits. The other ends of the second flexible conduits are fixedly connected with adjacent pneumatic three-way joints or a pneumatic controller. Compared with the prior art, the modular and reconfigurable pneumatic soft robot of the present invention can achieve human-machine safe interaction in an unstructured environment; has incomparable advantages in operating in narrow spaces and variable environments; and has great application prospects in fields such as bionic grasping of complex fragile objects and medical rehabilitation of patients.

Description

Technical Field

[0001] The present invention relates to the technical field of soft robots, and particularly to a modular and reconfigurable pneumatic soft robot. Background Art

[0002] Robots are one of the most popular scientific research and application fields at present, and are also hot topics widely concerned by all sectors of society. With the development of science and technology, robots are playing an increasingly important role in human society. However, a core challenge currently faced by robots is how to achieve safe human-robot interaction in unstructured environments.

[0003] Traditional rigid robots are composed of discrete rigid components connected by kinematic pairs, and then servo control is performed on the kinematic pairs to achieve arbitrary movement of the robot within the working space. However, the scenarios where such robots driven by motors and rigid components such as linkages and gears have been successfully applied are very limited, and most of them are limited to the structured environments of factories, performing repetitive actions following fixed instructions. In the unstructured environments in our daily lives that cannot be fully perceived and accurately modeled, since the rigid materials constituting the robot body cannot be passively deformed and adapt insufficiently to the external environment, once unexpected situations such as mechanical fatigue, sensor failure, or environmental mutation that were not considered in advance occur, if the robot still executes tasks according to mechanical pre-programming, it will inevitably cause damage to the robot's own structure or the surrounding environment.

[0004] The emergence of soft robot technology inspired by mollusks has brought a new solution to the above problems. Soft robot technology is an emerging discipline integrating bionics research, flexible materials, and intelligent control. Thanks to the bionic inspiration from nature and the continuous breakthroughs in intelligent materials, nowadays soft robots use little or no rigid materials. Instead, new composite silicones, hydrogels, shape memory alloys, electroactive polymers and other intelligent materials are used as the body. Their driving forms are not limited to motors and hydraulics. Some new intelligent actuators with diverse forms and characteristics provide rich choices for soft robots and also make it possible to design various special structures for soft robots. The particularity of the body materials and self-driving of soft robots endows them with inherent flexibility and large deformation ability, enabling them to interact safely with natural organisms in unstructured environments, effectively making up for the deficiencies of traditional rigid robots in this regard. From the perspective of the technology itself, the flexibility of soft robots is a subversion and impact on traditional rigid robot technology. Soft robots have a brand-new machine form. This disruptive principle-level innovation has solved the "stuck-neck" technical problems for many traditional industries, supported the leapfrog development of multiple traditional industries from manual production to automated production, and extended the application of global robot technology to broader scenarios, with infinite possibilities in the future. However, the application environment of hydrogel-based soft robots is easily restricted, the control of shape memory alloy-based soft robots is relatively difficult, and the processing of electroactive polymer-based soft robots is relatively difficult.

[0005] For the above reasons, the present invention proposes a modular reconfigurable pneumatic soft robot, which can achieve safe human-machine interaction in unstructured environments; has incomparable advantages in operating in narrow spaces and variable environments; and has great application prospects in fields such as bionic grasping of complex fragile objects and medical rehabilitation of patients. Summary of the Invention

[0006] The object of the present invention is to provide a modular reconfigurable pneumatic soft robot. A soft robot with properties such as passive compliance, continuous deformability, and interaction friendliness can achieve safe human-machine interaction in unstructured environments; and the self-reconfiguration function of the soft robot enables its end effector to reach any position in the three-dimensional working space more flexibly and conveniently.

[0007] The object of the present invention is achieved through the following technical solutions:

[0008] A modular and reconfigurable pneumatic soft robot, comprising: a flexible outer shell, in which an airbag is placed. The airbag is fixedly connected with a T-shaped nylon washer, the T-shaped nylon washer is fixedly connected with a first flexible conduit, the other end of the first flexible conduit is fixedly connected with a pneumatic three-way joint, and the other interface of the pneumatic three-way joint is fixedly connected with a second flexible conduit. The other end of the second flexible conduit is fixedly connected with an adjacent pneumatic three-way joint or a pneumatic controller.

[0009] Furthermore, the flexible outer shell is a spatial three-dimensional structure with geometric variable ability, which is composed of a wall surface with equal thickness and its internal cavity. The second, third, and fourth flexible outer shells are fixedly connected to two adjacent sides and the bevel of the first flexible outer shell to form the first planar layer of the soft robot body. A second planar layer is fixedly connected above the first planar layer, and the closely staggered connection of multiple planar layers jointly forms the soft robot body.

[0010] Furthermore, the airbag is placed in the internal cavity of the flexible outer shell and serves as the driving unit of the soft robot. The airbag is connected to the pneumatic controller through a pneumatic network system, and the pneumatic controller realizes the inflation or deflation of all airbags through the pneumatic network system to complete the driving control of the soft robot.

[0011] Furthermore, all the first flexible conduits, all the pneumatic three-way joints, and all the second flexible conduits jointly form a pneumatic network system.

[0012] Furthermore, the same pneumatic controller can be fixedly connected to different numbers of airbags at any positions through the pneumatic network system. The internal pressures of a group of airbags connected by the same pneumatic controller are equal, and a group of driving units with equal pressure can be composed of any number of airbags at any positions, so as to realize the reconfigurable function of the soft robot.

[0013] Even further, the flexible outer shell and the airbag have circular through holes with equal diameters at fixed positions.

[0014] Even further, only one airbag is placed in the cavity of the flexible outer shell.

[0015] Even further, the first flexible outer shell is fixedly connected to the second, third, and fourth flexible outer shells, and the first planar layer is fixedly connected to the second planar layer through soft glue.

[0016] Even further, the T-shaped nylon washer is fixedly connected to the airbag through soft glue.

[0017] Even further, the airbag is made of a flexible and deformable and soft film.

[0018] Even further, the flexible outer shell is made of a flexible and deformable and soft material.

[0019] Furthermore, the pneumatic controller includes a host computer, a slave computer, and an air proportional valve that are connected in sequence.

[0020] Compared with the prior art, the technical solution of the present invention has the following beneficial effects.

[0021] As can be seen from the technical solution provided by the present invention above, the design of the flexible shell enables conventional flexible materials to be used in the design and manufacture of soft robots, and the soft robots based on flexible materials have good environmental adaptability and interaction friendliness, and can achieve safe human-machine interaction in unstructured environments; they have incomparable advantages in operating in narrow spaces and variable environments; they have great application prospects in fields such as bionic grasping of complex fragile objects and medical rehabilitation of patients. In addition, the soft robot can be driven by the pneumatic network system to achieve different deformations of different flexible shells. By changing the number or position of the airbags connected by the same pneumatic controller through the pneumatic network system, the reconfigurable function of the soft robot body is finally realized. The continuous deformation ability of the soft robot in three-dimensional space is further reflected, enabling its end effector to reach any position in the three-dimensional working space more flexibly and conveniently. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can obtain other drawings without creative efforts based on these drawings.

[0023] Figure 1 Schematic diagram of the overall structure of a modular reconfigurable pneumatic soft robot provided in Embodiment 1 of the present invention;

[0024] Figure 2 Schematic diagram of the disassembly and assembly states of the flexible shell, airbag, and T-shaped nylon washer provided in Embodiment 1 of the present invention;

[0025] Figure 3 Schematic diagram of the disassembly and assembly states of adjacent planar layers provided in Embodiment 1 of the present invention;

[0026] Figure 4 Schematic diagram of the disassembly and assembly states of the pneumatic network system provided in Embodiment 1 of the present invention;

[0027] Figure 5 Schematic diagram of the reconstruction of the soft robot drive unit provided in Embodiment 2 of the present invention;

[0028] Figure 6Schematic diagram of the disassembly and assembly states of the flexible housing and the T-shaped nylon washer provided in Embodiment 3 of the present invention;

[0029] Figure 7 Schematic diagram of the force-induced bending of the soft robot structure provided in Embodiment 1 of the present invention in three-dimensional space; where 7-a is the schematic diagram of the soft robot structure in three-dimensional space; 7-b is the schematic diagram of the elongation of the soft robot structure along the z-axis; 7-c is the schematic diagram of the force-induced bending of the soft robot structure in the x-z plane; 7-d is the schematic diagram of the force-induced bending of the soft robot structure in the x-y plane;

[0030] In the above-mentioned drawings, 1 - flexible housing, 2 - flexible housing through-hole, 3 - airbag, 4 - airbag through-hole, 5 - T-shaped nylon washer, 6 - first flexible conduit, 7 - pneumatic three-way joint, 8 - second flexible conduit, 9 - pneumatic network system, 10 - first flexible housing, 11 - second flexible housing, 12 - third flexible housing, 13 - fourth flexible housing, 14 - first planar layer, 15 - second planar layer; Detailed implementation manners

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0032] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "thickness", "upper", "lower", "front", "rear", "left", "right", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0033] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0034] The embodiment of the present invention provides a modular reconfigurable pneumatic soft robot, such as Figure 1 As shown, it mainly includes: a flexible shell 1, an airbag 3 ( Figure 1 (not shown), a first flexible conduit 6, a pneumatic three-way connector 7, a second flexible conduit 8 and a pneumatic controller ( Figure 1 An airbag 3 is placed in the flexible shell 1, and the airbag is fixedly connected to a T-shaped nylon gasket 5, and the T-shaped nylon gasket is fixedly connected to a first flexible conduit 6, and the other end of the first flexible conduit is fixedly connected to a pneumatic three-way connector 7, and the remaining interface of the pneumatic three-way connector is fixedly connected to a second flexible conduit 8, and the other end of the second flexible conduit is fixedly connected to an adjacent pneumatic three-way connector or a pneumatic controller.

[0035] like Figure 2 As shown, the flexible shell 1 has a circular through hole 2, and the airbag 3 has a circular through hole 4. The flexible shell is a three-dimensional structure with geometrical changeability, the airbag 3 is placed in the internal cavity, and a T-shaped nylon gasket 5 is fixedly connected to the outer surface.

[0036] like Figure 3 As shown, the first flexible shell 10 of the smallest unit is fixedly connected to the second flexible shell 11, the third flexible shell 12, and the fourth flexible shell 13 on two adjacent sides and the oblique angle to form the first plane layer 14 of the soft robot body. The second plane layer 15 is fixedly connected above the first plane layer. The multiple plane layers are tightly staggered to form the soft robot body.

[0037] like Figure 4 As shown, all the first flexible conduits 6 , all the pneumatic three-way connectors 7 , and all the second flexible conduits 8 together constitute a pneumatic network system 9 .

[0038] like Figure 5As shown, the same pneumatic controller (not shown in the figure) is fixedly connected to a second flexible conduit 8, and the other end of the second flexible conduit is fixedly connected to a pneumatic three-way joint 7. The pneumatic three-way joint can be fixedly connected to different numbers of adjacent pneumatic three-way joints through the second flexible conduit. Different numbers of adjacent pneumatic three-way joints can be fixedly connected to any number of first flexible conduits 6. The other ends of different numbers of first flexible conduits can be fixedly connected to the internal airbags 3 of the flexible housing at any number and at any position. The internal pressures of a group of airbags controlled by the same pneumatic controller are equal. It can also be considered that a group of driving units with equal pressure can be composed of airbags at any number and at any position, so as to realize the reconfigurable function of the soft robot.

[0039] In a specific embodiment, the flexible housing is made of a material that can be flexibly deformed and is soft, such as silica gel, rubber, PVC, TPU, etc.

[0040] In a specific embodiment, only one airbag 3 is placed in the cavity of the flexible housing 1.

[0041] In a specific embodiment, the airbag is made of a film that can be flexibly deformed and is soft, such as PET film, polypropylene film, polyethylene film, etc.

[0042] In a specific embodiment, the airbags 3 in the internal cavity of the flexible housing 1 are all connected to the pneumatic controller through a T-shaped nylon washer 5, a first flexible conduit 6, a pneumatic three-way joint 7, and a second flexible conduit 8 in sequence.

[0043] In a specific embodiment, the diameter of the circular through-hole 2 of the flexible housing, the circular through-hole 4 of the airbag, and the T-shaped nylon washer are equal and are coaxially installed.

[0044] In a specific embodiment, all the fixed connections inside the soft robot body are soft glue connections.

[0045] In a specific embodiment, the pneumatic controller includes a host computer, a slave computer, an air ratio valve, etc. connected in sequence, which can be realized by conventional means.

[0046] In a specific embodiment, the T-shaped nylon washer 5, the first flexible conduit 6, the pneumatic three-way joint 7, and the second flexible conduit 8 can all be obtained through conventional channels.

[0047] For the convenience of understanding, the following is illustrated with specific examples.

[0048] Example 1

[0049] The flexible shell is processed and formed by 3D printing. The specific process is as follows: First, use solidworks (or other mechanical design software) to model the flexible shell, and control the wall thickness, cavity, and size of the circular through-hole to appropriate values during the modeling process. Then export it in stl format and import it into the 3D printer, and finally print it using silicone material.

[0050] The airbag is processed and formed using a polyethylene polymer film, and the edges are heat-sealed with a plastic sealer. The circular through-hole is manually processed using a punching tool.

[0051] The pneumatic controller uses a solution of an air compressor, an air source stabilizer, and an air proportional valve.

[0052] The host computer used by the soft robot is a computing component (usually a notebook or an industrial computer, meeting the requirements of cpu intel i3 or above and about 4G of memory).

[0053] The slave computer used by the soft robot is an arduino uno single-chip microcomputer.

[0054] As Figure 7 shown, it is a schematic diagram of the force-induced bending of the soft robot provided in Embodiment 1 of the present invention in three-dimensional space; where 7-a is a schematic diagram of the structure of the soft robot in three-dimensional space; 7-b is a schematic diagram of the elongation of the structure of the soft robot along the z-axis; 7-c is a schematic diagram of the force-induced bending of the structure of the soft robot in the x-z plane; 7-d is a schematic diagram of the force-induced bending of the structure of the soft robot in the x-y plane.

[0055] Embodiment 2

[0056] As Figure 5 shown, the present invention provides a modular reconfigurable pneumatic soft robot, which is further expanded according to the content in Specific Embodiment 1:

[0057] The same pneumatic controller is fixedly connected with a second flexible conduit 8, and the other end of the second flexible conduit is fixedly connected with a pneumatic three-way joint 7. The pneumatic three-way joint can be fixedly connected with different numbers of adjacent pneumatic three-way joints through the second flexible conduit. Different numbers of adjacent pneumatic three-way joints can be fixedly connected with any number of first flexible conduits 6. The other ends of different numbers of first flexible conduits can be fixedly connected with any number of airbags 3 at any positions. The internal pressures of a group of airbags controlled by the same pneumatic controller are equal. It can also be considered that a group of driving units with equal pressures can be composed of any number of airbags at any positions, so as to realize the reconfigurable function of the soft robot.

[0058] Embodiment 3

[0059] As Figure 6As shown in the figure, the embodiment of the present invention provides a modular and reconfigurable pneumatic soft robot, which is further expanded according to the content in Specific Embodiment 1:

[0060] A modular and reconfigurable pneumatic soft robot may not use an airbag structure when all driving pressures are small or the density and wall thickness of the flexible outer shell material are uniform (the flexible outer shell will not "bulge" after inputting the control air pressure).

[0061] In the above solution of the embodiment of the present invention, the design of the flexible outer shell enables conventional materials to be used in the design and manufacture of soft robots, and the soft robot based on flexible materials can achieve safe human-machine interaction in unstructured environments. In addition, through the reconfigurability of the drive unit, the ultra-high degree-of-freedom movement of the overall structure is realized, fully reflecting the continuous deformation ability of the soft robot in three-dimensional space. Different from the existing soft robot designs, this soft robot has incomparable advantages in operating in narrow spaces and variable environments; it has great application prospects in fields such as bionic grasping of complex fragile items and medical rehabilitation of patients. In addition, by driving the soft robot through the pneumatic network system, different deformations of different flexible outer shells can be achieved. By changing the number or position of the airbags connected by the same pneumatic controller through the pneumatic network system, the reconfigurable function of the soft robot body is finally realized. The continuous deformation ability of the soft robot in three-dimensional space is further reflected, enabling its end effector to reach any position in the three-dimensional working space more flexibly and conveniently.

[0062] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A modular and reconfigurable pneumatic soft robot, characterized in that, It includes: a flexible outer shell, inside which an airbag is placed. The airbag is fixedly connected with a T-shaped nylon washer, the T-shaped nylon washer is fixedly connected with a first flexible conduit, the other end of the first flexible conduit is fixedly connected with a pneumatic three-way joint, the other interfaces of the pneumatic three-way joint are fixedly connected with second flexible conduits, the other ends of the second flexible conduits are fixedly connected with adjacent pneumatic three-way joints or pneumatic controllers. The flexible outer shell is a three-dimensional spatial structure with geometric variable ability, and this spatial structure is composed of a wall surface with equal thickness and its internal cavity; two adjacent side surfaces and the bevel corners of the first flexible outer shell are fixedly connected with second, third, and fourth flexible outer shells to form the first planar layer of the soft robot body, and a second planar layer is fixedly connected above the first planar layer. The tight and staggered connection of multiple planar layers together forms the soft robot body.

2. The modular reconfigurable pneumatic soft robot according to claim 1, wherein The airbag is placed in the internal cavity of the flexible outer shell and serves as the driving unit of the soft robot. The airbag is connected to the pneumatic controller through a pneumatic network system, and the pneumatic controller realizes the inflation or deflation of all airbags through the pneumatic network system to complete the driving control of the soft robot.

3. A modular and reconfigurable pneumatic soft robot according to claim 2, characterized in that, All the first flexible conduits, all the pneumatic three-way joints, and all the second flexible conduits together form a pneumatic network system.

4. The modular reconfigurable pneumatic soft robot according to claim 2, characterized in that The same pneumatic controller can be fixedly connected to different numbers of airbags at arbitrary positions through the pneumatic network system. The internal pressures of a group of airbags connected by the same pneumatic controller are equal, and a group of driving units with equal pressure can be composed of any number of airbags at any position, so as to realize the reconfigurable function of the soft robot.

5. A modular and reconfigurable pneumatic soft robot according to claim 1, characterized in that, The flexible outer shell and the airbag have circular through holes with equal diameters at fixed positions.

6. A modular reconfigurable pneumatic soft robot according to claim 1, characterized in that, The T-shaped nylon washer is fixedly connected to the airbag through soft glue.

7. A modular and reconfigurable pneumatic soft robot according to claim 1, characterized in that, The first flexible outer shell is fixedly connected to the second, third, and fourth flexible outer shells, and between the first and second planar layers through soft glue.

8. A modular and reconfigurable pneumatic soft robot according to claim 1, characterized in that, Both the airbag and the flexible outer shell are made of deformable and soft materials.

Images