Modular actuation knuckles of a rigid origami-like dexterous hand actuated by dielectric elastomer

Abstract

The invention discloses a modular driving knuckle of a rigid origami-type dexterous hand driven by a dielectric elastomer, comprising a knuckle, a bracket unit, a driving assembly and a folding assembly, the bracket unit comprising two bracket bodies respectively located at two ends of the knuckle, the driving assembly comprising a dielectric elastomer driving mechanism, each dielectric elastomer driving mechanism connected between the two bracket bodies, the dielectric elastomer driving mechanism comprising a dielectric elastomer driver, the bending deformation of the dielectric elastomer driver drives the knuckle to deform, the folding assembly comprising a folding support mechanism, each folding support mechanism connected between the two bracket bodies, the folding support mechanism comprising a rigid origami unit, and the knuckle deformation drives the rigid origami unit to fold and deform. The knuckle has multiple degrees of freedom, good flexibility, and fast response speed, the origami structure improves the rigidity and load capacity of the knuckle, and the inherent flexibility of the dielectric elastomer material itself combined with the folding characteristics of the origami structure improves the environmental adaptability of the knuckle.

Description

Technical Field

[0001] The invention belongs to the technical field of intelligent robots, and in particular relates to a modular driving knuckle of a rigid origami-type dexterous hand driven by a dielectric elastomer. Background Art

[0002] With the continuous improvement of the intelligence level and operation ability of robots, dexterous hands have broad application prospects in aerospace, precision machinery, military, industry and medical equipment. Traditional dexterous finger joints mostly use motors, hydraulic pumps, cylinders, gears, tendons and other components to achieve drive and motion transmission. However, the joint transmission parts of the mechanical mechanism are more, the structure is more complex, the manufacturing difficulty is high, a larger working space is required, and the environmental adaptability is poor, and the applicable range of objects is small. Compared with traditional mechanical structure joints, the flexible finger joints driven by intelligent materials have a simpler structure, convenient control, and high environmental adaptability. However, their poor stiffness and insufficient driving force limit their scope of application. In addition, in recent years, origami structures have attracted widespread attention due to their good folding characteristics and large folding-expansion ratio. Scientists have also used origami technology in the design of robots. On the basis of retaining the advantages of robot intelligence, they have added the folding characteristics of origami to design a variety of origami robots, increasing their adaptability to the environment.

[0003] Reference patent application publication number: CN111923068A, a tendon-driven finger joint of anthropomorphic dexterous hand. The invention provides a tendon-driven finger joint of anthropomorphic dexterous hand, which uses fewer tendons to achieve more degrees of freedom, makes the structure compact and reasonable on the basis of being similar to the size of a human hand, uses the structural characteristics to achieve the tendon rope transmission effect, is highly integrated and has a certain degree of flexibility, and can achieve more precise position control. However, the tendon-driven finger joint provided by the design has only one degree of freedom and low flexibility.

[0004] Reference patent application publication number: CN111673781A, a variable stiffness humanoid robot gripper. The invention achieves the change of finger joint stiffness through a variable stiffness linear drive device, and cooperates with the relative movement of the thumb to improve the adaptability of the robot gripper to grasp the target. However, the design uses a built-in electromechanical system to achieve the joint bending of the dexterous hand, the internal structure is relatively complex, and the use of components such as sliders, nuts and screws is relatively large, and the movement space is limited, the assembly is relatively troublesome, and the load deadweight is relatively low.

[0005] Reference patent application publication number: CN108177156A, a variable stiffness soft hand driven by structural decoupling. This invention drives the movements of various parts of the finger through shape memory alloys, and at the same time controls its Young's modulus by changing the temperature of the shape memory alloy through electric current, so as to achieve variable stiffness of the finger to obtain more precise grasping movements. It has a simpler structure and no mechanical fatigue and wear problems, and can also reduce the risk of interaction between the manipulator and the human, thus providing a feasible structural model for the development of soft hands. However, the effective power of current thermal drive is low and the driving time is long. Summary of the invention

[0006] In view of the above-mentioned deficiencies in the prior art, the present invention provides a modular driven knuckle of a rigid origami-type dexterous hand driven by a dielectric elastomer. The knuckle has multiple degrees of freedom, good flexibility, and fast response speed. The origami structure improves the rigidity and load capacity of the knuckle. The inherent flexibility of the dielectric elastomer material itself combined with the folding characteristics of the origami structure improves the environmental adaptability of the knuckle.

[0007] The present invention provides the following technical solution: A modular driving knuckle of a rigid origami-type dexterous hand driven by a dielectric elastomer, comprising a knuckle, wherein the knuckle comprises:

[0008] A bracket unit, the bracket unit comprising two bracket bodies respectively located at two ends of the finger joint;

[0009] A driving assembly, wherein the driving assembly comprises a dielectric elastomer driving mechanism, each of the dielectric elastomer driving mechanisms is connected between the two support bodies, the dielectric elastomer driving mechanism comprises a dielectric elastomer driver, and the bending deformation of the dielectric elastomer driver drives the deformation of the knuckle;

[0010] A folding assembly, wherein the folding assembly comprises a folding support mechanism, each of the folding support mechanisms is connected between the two support bodies, and the folding support mechanism comprises a rigid origami unit, and the deformation of the knuckles drives the rigid origami unit to fold and deform.

[0011] Furthermore, the driving assembly includes a plurality of the dielectric elastomer driving mechanisms sequentially arranged along the circumference of the knuckle, and the folding assembly includes a plurality of the folding support mechanisms sequentially arranged along the circumference of the knuckle.

[0012] Furthermore, each of the dielectric elastomer drive mechanisms comprises two dielectric elastomer drives respectively connected to the two support bodies, the junction of the two dielectric elastomer drives of the same dielectric elastomer drive mechanism is located at the point where the length of the knuckle is divided into two equal parts, and the junction of the two dielectric elastomer drives of the same dielectric elastomer drive mechanism is bent and deformed toward the inner side of the knuckle,

[0013] Each of the folding support mechanisms comprises two rigid origami units respectively connected to the two support bodies; the junction of the two rigid origami units of the same folding support mechanism is symmetrically located at the point where the length of the finger joint is divided into two equal parts, and both of the two rigid origami units of the same folding support mechanism are folded and deformed toward the inner side of the finger joint.

[0014] Furthermore, the dielectric elastomer driver includes a substrate and a dielectric elastomer film stacked together, the substrate is configured as a single layer or multiple layers stacked together, the dielectric elastomer film is configured as multiple layers, both surfaces of each layer of the dielectric elastomer film are covered with flexible electrodes, and when a voltage is applied to the flexible electrodes, the dielectric elastomer driver bends toward the substrate side.

[0015] Furthermore, the dielectric elastomer film is made of polyacrylate or silicone rubber material, the substrate is made of a flexible material with greater rigidity than the dielectric elastomer film, and the flexible electrode is made of a mixture of carbon black, silicone and silicone oil.

[0016] Furthermore, the fold of each of the rigid origami units is a single-vertex six-fold diamond pattern, and the folding assembly composed of the rigid origami units meets the movement requirements of knuckle stretching, compression and bending.

[0017] Furthermore, the support body is a hexagonal thin plate, and the hexagonal thin plate includes first sides and second sides that are alternately arranged, three of the first sides are used to connect to the dielectric elastomer driving mechanism, and three of the second sides are used to connect to the foldable support mechanism.

[0018] Furthermore, the input voltages of the dielectric elastomer driving mechanisms connected to the three first sides are independently controlled, and when the input voltages are the same, the knuckles achieve compression movement, and when the input voltages are different, the knuckles achieve bending movement.

[0019] Furthermore, the bracket body is provided with a plurality of clamping plates for adhering the dielectric elastomer drivers connected thereto, and the two dielectric elastomer drivers of the dielectric elastomer driving mechanism are connected by adhesive bonding.

[0020] Furthermore, the support body and the rigid origami unit are both manufactured by 3D printing, and the folds of the foldable support mechanism are realized by 3D printing flexible materials at the connection points of different panels.

[0021] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0022] 1) The present invention discloses a modular driving knuckle of a rigid origami-style dexterous hand driven by a dielectric elastomer, which can realize the extension and bending movement of the knuckle through the electromechanical coupling of the dielectric elastomer driver. The knuckle has multiple degrees of freedom, good flexibility and fast response speed;

[0023] 2) The present invention discloses a modular driving knuckle of a rigid origami-type dexterous hand driven by a dielectric elastomer, which combines an origami structure with a dielectric elastomer drive to improve the rigidity and load capacity of the knuckle and ensure the controllability of the knuckle movement. The inherent flexibility of the dielectric elastomer material itself combined with the folding characteristics of the origami structure improves the environmental adaptability of the knuckle;

[0024] 3) A modular driving knuckle of a rigid origami-style dexterous hand driven by a dielectric elastomer disclosed in the present invention, wherein the multi-layer structure design of the dielectric elastomer driver and the increase in the number of driving mechanisms can increase the driving force of the knuckle;

[0025] 4) The present invention discloses a modular driving knuckle of a rigid origami-style dexterous hand driven by a dielectric elastomer, in which the dielectric elastomer driving mechanism and the folding support mechanism are symmetrically arranged, resulting in a larger compression displacement and bending angle, and a larger working space. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings in the specification, which constitute a part of the present application, are used to provide further understanding of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute improper limitations on the present application.

[0027] Figure 1 It is an overall schematic diagram of the dexterous finger joints in the present invention;

[0028] Figure 2 It is a partial schematic diagram of the dexterous finger joint of the present invention without the dielectric elastic drive component;

[0029] Figure 3 It is a partial schematic diagram of the dexterous finger joint of the present invention without folding components;

[0030] Figure 4 A schematic diagram of a dielectric elastomer actuator according to the present invention;

[0031] Figure 5 This is a schematic diagram of the dielectric elastomer driver before voltage is input in the present invention;

[0032] Figure 6 This is a schematic diagram of the dielectric elastomer driver of the present invention after voltage is input;

[0033] Figure 7 is a schematic diagram of the knuckle when the input voltages of the dielectric elastomer drivers on different sides are the same in the present invention;

[0034] Figure 8 It is a schematic diagram of the knuckle when the input voltages of the dielectric elastomer driver on different sides are different in the present invention.

[0035] Among them, 1. bracket body; 11. splint; 2. dielectric elastomer driving mechanism; 21. dielectric elastomer driver; 211. substrate; 212. dielectric elastomer film; 213. flexible electrode; 3. foldable supporting mechanism; 31. rigid origami unit; 32. transverse crease; 33. single vertex six-crease diamond pattern. DETAILED DESCRIPTION

[0036] The specific implementation of the present invention is further described in detail below in conjunction with the drawings and examples.

[0037] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those generally understood by those of ordinary skill in the art to which the present application belongs. It should be noted that the terms used here are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context otherwise clearly indicates, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "include" and / or "include" are used in this specification, it indicates that there are features, steps, operations, devices, components and / or combinations thereof. In the present disclosure, the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "side", "bottom" etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only a relationship word determined for the convenience of describing the structural relationship of each component or element of the present disclosure, and does not specifically refer to any component or element in the present disclosure, and cannot be understood as a limitation to the present disclosure. In the present disclosure, terms such as "fixed connection", "connected", "connection", etc. should be understood in a broad sense, indicating that it can be fixedly connected, integrally connected or detachably connected; it can be directly connected or indirectly connected through an intermediate medium. For relevant scientific research or technical personnel in this field, the specific meanings of the above terms in the present disclosure can be determined according to specific circumstances, and they cannot be understood as limitations on the present disclosure.

[0038] The following is a preferred embodiment for illustrating the present invention, but is not intended to limit the scope of the present invention.

[0039] Embodiment 1

[0040] See also Figures 1 to 3 As shown in the figure, a modular driving knuckle of a rigid origami-type dexterous hand driven by a dielectric elastomer includes knuckles, and the knuckles include:

[0041] A bracket unit, the bracket unit comprising two bracket bodies 1 respectively located at two ends of the finger joint;

[0042] A driving assembly, wherein the driving assembly comprises a dielectric elastomer driving mechanism 2, each of which is connected between two bracket bodies 1, and the dielectric elastomer driving mechanism 2 comprises a dielectric elastomer driver 21, and the bending deformation of the dielectric elastomer driver 21 drives the deformation of the knuckles;

[0043] The folding assembly includes a folding support mechanism 3, each folding support mechanism 3 is connected between two bracket bodies 1, and the folding support mechanism 3 includes a rigid origami unit 31, and the knuckle deformation drives the rigid origami unit 31 to fold and deform.

[0044] In the above, the extension and bending movements of the knuckles are achieved through the electromechanical coupling of the dielectric elastomer actuator. Combining the origami structure with the dielectric elastomer drive can improve the rigidity and load capacity of the knuckles and ensure the controllability of the knuckle movement. The inherent flexibility of the dielectric elastomer material itself combined with the folding characteristics of the origami structure improves the environmental adaptability of the knuckles.

[0045] In the preferred implementation manner of this embodiment, each driving component includes three dielectric elastomer driving mechanisms arranged in sequence along the circumference of the knuckle, each dielectric elastomer driving mechanism includes two adjacent dielectric elastomer driving mechanisms 2, and each folding component includes three folding support mechanisms 3 arranged in sequence along the circumference of the knuckle, and each folding support mechanism includes a folding support mechanism 3.

[0046] In the above, by setting up multiple dielectric elastomer driving mechanisms and multiple origami mechanisms, on the one hand, the driving force, rigidity and load capacity of the knuckles can be increased, and on the other hand, the knuckles have multiple degrees of freedom, good flexibility and fast response speed.

[0047] In the preferred implementation manner of this embodiment, each dielectric elastomer drive mechanism 2 includes two dielectric elastomer drivers 21 respectively connected to two bracket bodies 1, and the junction of the two dielectric elastomer drivers 21 of the same dielectric elastomer drive mechanism 2 is located at the half of the length of the knuckle and the junction of the two dielectric elastomer drivers 21 of the same dielectric elastomer drive mechanism 2 is bent and deformed toward the inner side of the knuckle.

[0048] Each folding support mechanism 3 includes two rigid origami units 31 respectively connected to two support bodies 1. The junction of the two rigid origami units 31 of the same folding support mechanism 3 is located at the point where the length of the knuckle is divided into two equal parts, and the two rigid origami units 31 of the same folding support mechanism 3 are both folded and deformed toward the inside of the knuckle.

[0049] In the above, the dielectric elastomer driving mechanism and the folding support mechanism are symmetrically arranged, so that the resulting compression displacement and bending angle are larger and the working space is also larger.

[0050] In the preferred implementation manner of this embodiment, the bracket body 1 is a hexagonal thin plate, and the hexagonal thin plate includes first sides and second sides arranged alternately, the three first sides are used to connect to the dielectric elastomer driving mechanism 2, and the three second sides are used to connect to the foldable support mechanism 3.

[0051] In the preferred implementation manner of this embodiment, the input voltages of the three dielectric elastomer driving mechanisms connected to the three first sides are independently controlled. When the input voltages are the same, the knuckles achieve compression movement, and when the input voltages are different, the knuckles achieve bending movement.

[0052] In the preferred implementation mode of the present embodiment, the fold of each rigid origami unit 31 is a single-vertex six-fold diamond pattern 33, and the folding assembly composed of the rigid origami units 31 meets the movement requirements of knuckle stretching, compression and bending.

[0053] In a preferred implementation manner of this embodiment, the bracket body 1 is provided with a plurality of clamping plates 11 for pasting the dielectric elastomer drivers 21 connected thereto, and the two dielectric elastomer drivers 21 of each dielectric elastomer driving mechanism 2 are pasted and connected.

[0054] In the preferred implementation mode of this embodiment, the support body 1 and the rigid origami unit 31 are both manufactured by 3D printing, and the folding lines of the foldable support mechanism 3 are realized by 3D printing flexible materials at the connection points of different panels.

[0055] See also Figures 4 to 6 In the preferred implementation mode of this embodiment, the dielectric elastomer driver 21 includes a substrate 211 and a dielectric elastomer film 212 stacked together, the substrate 211 is configured as a single layer, and the dielectric elastomer film 212 is configured as multiple layers, and both surfaces of each layer of the dielectric elastomer film 212 are covered with flexible electrodes 213. When a voltage is applied to the flexible electrode 213, the dielectric elastomer driver 21 bends toward the substrate 211 side.

[0056] In the above, the multi-layer structure design of the dielectric elastomer actuator can increase the driving force of the knuckle.

[0057] In the preferred implementation manner of this embodiment, the dielectric elastomer film 212 is made of polyacrylate or silicone rubber material, the substrate 211 is made of a flexible material with greater rigidity than the dielectric elastomer film 212, and the flexible electrode 213 is made of a mixture of carbon black, silicone and silicone oil.

[0058] See also Figure 7 and Figure 8In the preferred implementation mode of this embodiment, every two dielectric elastomer driving mechanisms 2 are on the same first side and the input voltages of the four dielectric elastomer drivers 21 included therein are the same, thus producing the same bending deformation; when the input voltages of the three dielectric elastomer driving mechanisms 2 connected to the three first sides are the same, the knuckles realize compression movement, and when the input voltage disappears, the knuckles will automatically stretch and return to their initial state; when the input voltages of the three dielectric elastomer driving mechanisms 2 connected to the three first sides are different, the knuckles realize bending movement, and through the electromechanical coupling of the three dielectric elastomer driving mechanisms, the bending movement of the knuckles in different directions can be realized; increasing the number of dielectric elastomer drivers can also increase the driving force of the knuckles.

[0059] In the preferred implementation of this embodiment, a single rigid paper folding unit 31 includes two identical large triangular plates and four identical small triangular plates, thereby forming a single-vertex six-fold diamond pattern 33 .

[0060] The above is a description of the embodiments of the present invention. Through the above description of the disclosed embodiments, professionals and technicians in the field can implement or use the present invention. Various modifications to the embodiments of the present invention will be obvious to professionals and technicians in the field. The general principles defined in this article can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown in this article, but should conform to the widest scope consistent with the principles and novel features disclosed in this article.

Claims

1. A modular driving knuckle of a rigid origami-type dexterous hand driven by a dielectric elastomer, comprising a knuckle, characterized in that: The knuckles include: A bracket unit, the bracket unit comprising two bracket bodies respectively located at two ends of the finger joint; A driving assembly, wherein the driving assembly comprises a dielectric elastomer driving mechanism, each of the dielectric elastomer driving mechanisms is connected between the two support bodies, the dielectric elastomer driving mechanism comprises a dielectric elastomer driver, and the bending deformation of the dielectric elastomer driver drives the deformation of the knuckle; A folding assembly, wherein the folding assembly comprises a folding support mechanism, each of the folding support mechanisms is connected between the two support bodies, and the folding support mechanism comprises a rigid origami unit, and the deformation of the knuckle drives the rigid origami unit to fold and deform; The driving assembly includes a plurality of the dielectric elastomer driving mechanisms sequentially arranged along the circumference of the knuckle, and the folding assembly includes a plurality of the folding support mechanisms sequentially arranged along the circumference of the knuckle; Each of the dielectric elastomer drive mechanisms comprises two dielectric elastomer drivers respectively connected to the two support bodies, the junction of the two dielectric elastomer drivers of the same dielectric elastomer drive mechanism is located at the half of the length of the knuckle and the junction of the two dielectric elastomer drivers of the same dielectric elastomer drive mechanism is bent and deformed toward the inside of the knuckle; Each of the folding support mechanisms comprises two rigid origami units respectively connected to the two support bodies; the junction of the two rigid origami units of the same folding support mechanism is located at the point where the length of the finger joint is divided into two equal parts, and both of the two rigid origami units of the same folding support mechanism are folded and deformed toward the inner side of the finger joint.

2. The modular driving knuckle of the dexterous hand according to claim 1, characterized in that: The dielectric elastomer driver includes a substrate and a dielectric elastomer film stacked together, the substrate is configured as a single layer or multiple layers stacked together, the dielectric elastomer film is configured as multiple layers, both surfaces of each layer of the dielectric elastomer film are covered with flexible electrodes, and when a voltage is applied to the flexible electrodes, the dielectric elastomer driver bends toward the substrate side.

3. The modular driving knuckle of the dexterous hand according to claim 2, characterized in that: The dielectric elastomer film is made of polyacrylate or silicone rubber material, the substrate is made of a flexible material with greater rigidity than the dielectric elastomer film, and the flexible electrode is made of a mixture of carbon black, silicone and silicone oil.

4. The modular driving knuckle of the dexterous hand according to claim 1, characterized in that: The fold of each rigid origami unit is a single-vertex six-fold diamond pattern, and the folding assembly composed of the rigid origami units meets the movement requirements of knuckle stretching, compression and bending.

5. The modular driving knuckle of the dexterous hand according to claim 1, characterized in that: The support body is a hexagonal thin plate, and the hexagonal thin plate includes first sides and second sides that are alternately arranged, three of the first sides are used to connect to the dielectric elastomer driving mechanism, and three of the second sides are used to connect to the foldable support mechanism.

6. The modular driving knuckle of the dexterous hand according to claim 5, characterized in that: The input voltages of the three dielectric elastomer driving mechanisms connected to the three first sides are independently controlled. When the input voltages are the same, the knuckles achieve compression movement, and when the input voltages are different, the knuckles achieve bending movement.

7. The modular driving knuckle of the dexterous hand according to claim 1, characterized in that: The bracket body is provided with a plurality of clamping plates for pasting the dielectric elastomer drivers connected thereto, and the two dielectric elastomer drivers of the dielectric elastomer driving mechanism are pasted and connected.

8. The modular driving knuckle of the dexterous hand according to claim 1, characterized in that: The support body and the rigid origami unit are both manufactured by 3D printing, and the folds of the foldable support mechanism are realized by 3D printing flexible materials at the connection points of different panels.

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