CN115339036A

CN115339036A - 3D variable deformation rigidity skin based on laminar flow blocking mechanism and preparation method thereof

Info

Publication number: CN115339036A
Application number: CN202210890879.6A
Authority: CN
Inventors: 张征; 周玉婷; 南茹怡; 孙敏; 张广; 吴化平; 李吉泉; 彭翔; 丁浩
Original assignee: Zhejiang University of Technology ZJUT
Current assignee: Zhejiang University of Technology ZJUT
Priority date: 2022-07-27
Filing date: 2022-07-27
Publication date: 2022-11-15

Abstract

The invention discloses a 3D variable deformation rigidity skin based on a laminar flow blocking mechanism and a preparation method thereof, and relates to the technical field of robots.

Description

3D variable deformation rigidity skin based on laminar flow blocking mechanism and preparation method thereof

Technical Field

The invention relates to the technical field of robots, in particular to a 3D variable deformation rigidity skin based on a laminar flow blocking mechanism and a preparation method thereof.

Background

Due to high flexibility, ductility, adaptability and safety, the soft robot has attracted wide interest in the field of robots and related fields, and is widely applied to various fields such as medical treatment, military, industry and the like. The soft body robot technology is a branch field of the robot technology, generally made of flexible and self-adaptive materials, and the body is soft, but the development of the soft body robot is limited due to the fact that the rigidity of the body is insufficient seriously. The rigidity-variable robot is characterized in that a rigidity-variable module is added on a soft robot, so that the rigidity-variable robot has the advantages of the rigidity-variable module and the soft robot, and not only can the rigidity be better, but also the rigidity can be higher. Aiming at the variable stiffness research in the field of soft robots, the blocking variable stiffness method is widely applied to the requirements of the soft robots for variable stiffness because of the advantages of simple design, low cost, no need of temperature dependence and the like.

The plug stiffness variation method can realize the mutual conversion between a fluid state and a solid state. There are three different types of clogging mechanisms in soft robots: particle plugging, laminar flow plugging, and fiber plugging. The three methods are similar in structure, and films are filled with non-stretchable materials; the principle is the same, negative pressure is applied to increase the shear stress of the material in the elastic film; at present, the particle blockage and the laminar flow blockage are applied more, the particle blockage is high in deformability in a fluid state and strong in external conformal capability, but a large amount of blocking particles are needed, the weight is large, and the control is not accurate; at present, the change range of rigidity provided by laminar flow blockage is large, but the deformation capability is poor, and the adaptability to the environment is weak.

Disclosure of Invention

In view of the problems in the prior art, the invention aims to provide a 3D variable deformation stiffness skin based on a laminar flow plugging mechanism and a preparation method thereof, wherein the skin has better flexibility by improving the structure of a laminar flow plugging element, and meanwhile, when higher stiffness is required, higher stiffness can be provided, so that the skin has better environment adaptability.

The technical scheme of the invention is as follows:

the utility model provides a 3D variable deformation rigidity covering based on laminar flow blocks up mechanism, blocks up component, vacuum tube and upper silicone rubber membrane including lower floor's silicone rubber membrane, a set of stand, a set of discrete formula, lower floor's silicone rubber membrane be equipped with a set of stand on the surface, and the cover is equipped with a plurality of layers of discrete formula and blocks up the component on every stand, and wherein the component has been blockked up to multilayer discrete formula has constituted the jam layer, the one end of vacuum tube sets up on lower floor's silicone rubber membrane, its other end and vacuum pump connection, upper silicone rubber membrane cladding is sealed on lower floor's silicone rubber membrane.

Further, the 3D variable deformation rigidity skin based on the laminar flow plugging mechanism is characterized in that the discrete plugging elements are hexagonal, circular or rectangular in shape and made of PET.

The invention also provides a preparation method of the 3D variable deformation rigidity skin based on the laminar flow blocking mechanism, which comprises the following steps:

1) Respectively manufacturing a first mold of the lower silicone rubber film and a second mold of the upper silicone rubber film by a laser cutting processing method according to a preset skin size, and reserving after manufacturing;

2) Manufacturing a stand column and a discrete type plugging element for later use;

3) Pouring the two types of silicon rubber into a beaker, stirring and mixing the silicon rubber and the beaker by using a glass rod, putting the beaker into a vacuum drying oven for vacuumizing after the silicon rubber and the beaker are fully mixed until no bubbles emerge, slowly pouring the mixture into the first mold and the second mold which are manufactured in the step 1) until the mixture reaches the edge, then placing the first mold and the second mold on a flat surface for curing, and obtaining a lower silicon rubber film and an upper silicon rubber film for later use after the curing is finished;

4) Fixing the stand column manufactured in the step 2) on the surface of the lower-layer silicon rubber membrane prepared in the step 3) by using tweezers according to the pre-layout requirement, fixing the discrete plugging element manufactured in the step 2) on the stand column, and sealing the top of the stand column by using a silicon rubber adhesive;

5) After the step 4) is finished, arranging a vacuum tube on the surface of the lower silicon rubber film, covering the upper silicon rubber film prepared in the step 3), and pressing the edge for sealing to obtain the skin to be prepared;

6) And (4) carrying out air tightness test on the skin prepared in the step 5).

Further, the first mold and the second mold in the step 1) have the same structure and are both transparent molds.

Further, the specific operation of step 2) is as follows: cutting PET into a plurality of discrete blocking elements by using a laser cutting machine; the silicone rubber tube is cut into a plurality of upright columns with the length of 10 mm.

Further, the volume ratio of the two types of silicon rubber in the step 3) is 1; placing the two fully mixed silicon rubbers under the negative pressure condition of-0.1 MPa for 2-3 minutes until no bubbles emerge from the beaker; and the material in the first die and the second die is cured for 7 hours.

Further, in step 4), an adhesive is applied around the outer surface of the pillar to form a ring.

Further, one end of the vacuum tube in the step 5) is positioned on the lower silicon rubber film, and the end part is positioned outside the edgemost upright post.

Further, if the skin leaks in the step 6), filling the skin with a syringe filled with silicon rubber.

Compared with the prior art, the invention has the following beneficial effects:

1) By adopting the technical scheme of the invention, the discrete blocking element is adopted to replace the traditional integral blocking element, and the multilayer blocking element is adopted, so that the skin prepared by the method has better flexibility, and can provide larger rigidity when needing larger rigidity, thereby having better environment adaptability;

2) When the interior of the skin is at atmospheric pressure, namely when vacuumizing is not performed, the skin is flexible, 3D deformation can be realized, objects with different outline contours are enveloped, reversible multidirectional stretching can be realized on the skin, and the skin has good conformability;

3) When the skin is vacuumized, discrete blocking elements inside the skin are compressed, the rigidity of the skin is increased, and the skin can keep the shape and the contour before activation and has stronger bearing capacity.

Drawings

FIG. 1 is a schematic view of a variable stiffness skin-side configuration of the present invention;

FIG. 2 is a schematic top view of a variable stiffness skin of a hexagonal discrete occlusion element of the present invention;

FIG. 3 is a schematic structural view of an internal structural blockage layer of the skin at atmospheric pressure according to the present invention;

FIG. 4 is a schematic structural view of an internal structural plugging layer of the skin under negative pressure according to the present invention;

FIG. 5 is a graph comparing the effects of varying stiffness of different discrete occlusion elements;

FIG. 6 is a comparison of skin stiffness at different negative pressures;

FIG. 7 is a schematic diagram of a variable stiffness skin implementing stretch collapsibility;

FIG. 8 is a schematic diagram of a variable stiffness skin implementing a 3D deformable crimp envelope;

fig. 9 is a schematic diagram of a variable stiffness skin capable of conforming to objects of different contours and having a certain bearing capacity.

In the figure: 1. a lower silicone rubber film; 2. a column; 3. a discrete occlusion element; 4. a vacuum tube; 5. an upper silicone rubber film; 6. and (4) a blocking layer.

Detailed Description

The invention will be further described with reference to the following figures and examples, to which, however, the scope of protection of the invention is not limited.

As shown in fig. 1-2, a 3D variable deformation rigidity covering based on laminar flow blocking mechanism, including lower floor's silicon rubber membrane 1, a set of stand 2, a set of discrete block component 3, vacuum tube 4 and upper silicone rubber membrane 5, lower floor's silicon rubber membrane 1 is equipped with a set of stand 2 on the surface, every stand 2 goes up the cover and is equipped with a plurality of layers of discrete block component 3, wherein component 3 has been blockked up to multilayer discrete block component 6, the one end of vacuum tube 4 sets up on lower floor's silicon rubber membrane 1, its other end and vacuum pump connection, upper silicone rubber membrane 5 cladding is sealed on lower floor's silicon rubber membrane 1.

According to the 3D deformable skin based on the laminar flow plugging mechanism, the discrete plugging element 3 is hexagonal, circular or rectangular in shape and made of PET.

As illustrated in fig. 3 to 4, when the pressure is atmospheric (i.e. no negative pressure is applied to the skin), all the plugging layers 6 are discrete and can freely slide on each other, the overall softness is drawability, and when the pressure is negative (i.e. vacuum is applied to the skin), the silicone mold and the plugging layers 6 are pressed tightly and have small deformation, the layers are pressed tightly, the friction is large, and the overall hardening is small deformation.

1) Respectively manufacturing a first mold of the lower silicon rubber film 1 and a second mold of the upper silicon rubber film 5 by a laser cutting processing method according to a preset skin size, and reserving after manufacturing; the first die and the second die are the same in structure and are transparent dies;

2) Manufacturing a stand column 2 and a discrete type plugging element 3 for standby;

cutting PET into a plurality of discrete plugging elements 3 by a laser cutting machine; shearing the silicone rubber tube into a plurality of upright posts 2 with the length of 10 mm;

3) Pouring the two types of silicon rubber into a beaker, stirring and mixing the silicon rubber and the beaker by using a glass rod, putting the beaker into a vacuum drying oven for vacuumizing after the silicon rubber and the beaker are fully mixed until no bubbles emerge, slowly pouring the mixture into the first mold and the second mold which are manufactured in the step 1) until the mixture reaches the edge, then placing the first mold and the second mold on a flat surface for curing, and obtaining a lower silicon rubber film 1 and an upper silicon rubber film 5 for later use after the curing is finished;

wherein the volume ratio of the two silicone rubbers is 1; placing the two fully mixed silicon rubbers under the negative pressure condition of-0.1 MPa for 2-3 minutes until no bubbles emerge from the beaker; the material in the first die and the second die is cured for 7 hours;

4) Fixing the stand column 2 manufactured in the step 2) on the surface of the lower-layer silicon rubber membrane 1 prepared in the step 3) by using tweezers according to the pre-layout requirement, fixing the discrete plugging elements 3 manufactured in the step 2) on the stand column 2, sealing the top of the stand column 2 by using a silicon rubber adhesive, and coating the adhesive on the periphery of the outer surface of the stand column 2 to form a ring so as to prevent the discrete plugging elements 3 from falling off;

5) After the step 4) is finished, arranging a vacuum tube 4 on the surface of the lower silicon rubber film 1, wherein one end of the vacuum tube 4 is positioned on the vacuum tube 1, and the end part is positioned outside the edgemost upright post 2), covering the upper silicon rubber film 5 prepared in the step 3), and pressing the edge for sealing to obtain the skin to be prepared;

6) And (5) carrying out air tightness test on the skin prepared in the step 5).

Example 1

The skin size is preset to be 150 mm x 150 mm and the effective occlusion area size is 130mm x 130 mm.

1) Respectively manufacturing a first transparent mold of a lower silicone rubber film 1 and a second transparent mold of an upper silicone rubber film 5 by adopting a laser cutting processing method according to a preset skin size, printing pre-designed manuscript paper according to the actual skin size 1, and placing the paper under the transparent molds to guide the subsequent steps;

2) Cutting PET into a plurality of hexagonal discrete plugging elements 3 by using a laser cutting machine; shearing a silicone rubber pipe with the diameter of 2mm into a plurality of upright posts 2 with the length of 10 mm;

3) Pouring two-component silicone rubber of Slow A and B of Smooth-On company into a beaker according to the volume ratio of 1, stirring the mixture clockwise by using a glass rod, fully mixing the mixture, according to the experience, the size of the mixture needs 40 g of DS Slow to ensure that the film is not easy to tear under the condition of enough thinness, putting the mixture into a vacuum drying box for vacuumizing after stirring, placing the mixture for 2 to 3 minutes under the negative pressure condition of-0.1 MPa until no bubbles emerge from the beaker, then slowly pouring the mixture into a first transparent mould and a second transparent mould until the mixture reaches the edge, and then placing the mixture On a flat surface for curing for 7 hours to form a lower silicone rubber film 1 and an upper silicone rubber film 5;

4) Fixing the manufactured upright post 2 on the surface of the lower layer silicon rubber membrane 1 by using tweezers according to the pre-layout requirement, then fixing the hexagonal discrete plugging element 3 on the upright post 2, sealing the top of the upright post 2 by using a silicon rubber adhesive, and coating the adhesive on the periphery of the outer surface of the upright post 1 to form a ring so as to prevent the discrete plugging element 3 from falling off;

5) Arranging a vacuum tube 4 on the surface of the lower silicon rubber film 1, wherein one end of the vacuum tube 4 is positioned on the lower silicon rubber film 1, the end part is positioned outside the edgemost upright post 2, the other end of the vacuum tube is connected with a vacuum pump, then covering the prepared upper silicon rubber film 5, and pressing the edge for sealing to obtain the skin I to be prepared;

6) And (4) carrying out air tightness test on the prepared skin I, and filling the skin I by using an injector filled with silicon rubber if the skin is leaked.

Example 2

2) Cutting PET into a plurality of circular discrete plugging elements 3 (the circular plugging elements share the same center point with the hexagon in the embodiment 1 and have the size of the circumscribed circle of the hexagon) by using a laser cutting machine; shearing a silicone rubber pipe with the diameter of 2mm into a plurality of upright posts 2 with the length of 10 mm;

3) Pouring two-component silicone rubber of Slow A and B of Smooth-On company into a beaker according to the volume ratio of 1, and stirring and fully mixing the silicone rubber clockwise by using a glass rod, wherein according to experience, the size of the silicone rubber needs 40 g of DS Slow to ensure that a film is not easy to tear under the condition of enough thin, stirring the silicone rubber and the DS Slow to put into a vacuum drying box for vacuumizing treatment, placing the mixture under the negative pressure condition of-0.1 MPa for 2 to 3 minutes until no bubble emerges in the beaker, then slowly pouring the mixture into a first transparent mould and a second transparent mould until the mixture reaches the edge, and then placing the mixture On a flat surface for curing for 7 hours to form a lower silicone rubber film 1 and an upper silicone rubber film 5;

4) Fixing the manufactured upright post 2 on the surface of the lower layer silicon rubber membrane 1 by using tweezers according to the pre-layout requirement, then fixing the hexagonal discrete plugging element 3 on the upright post 2, sealing the top of the upright post 2 by using a silicon rubber adhesive, and coating the adhesive on the periphery of the outer surface of the upright post 2 to form a ring so as to prevent the discrete plugging element 3 from falling off;

5) Arranging a vacuum tube 4 on the surface of the lower silicon rubber film 1, wherein one end of the vacuum tube 4 is positioned on the lower silicon rubber film 1, the end part is positioned outside the edgemost upright post 2, the other end of the vacuum tube is connected with a vacuum pump, then covering the prepared upper silicon rubber film 5, and pressing the edge for sealing to obtain a skin II to be prepared;

6) And (4) performing air tightness test on the prepared second skin, and filling the second skin by using an injector filled with silicon rubber if the second skin leaks.

Example 3

2) Cutting PET into a plurality of rectangular discrete plugging elements 3 by using a laser cutting machine (the rectangular plugging elements share the same center point with the hexagon of the embodiment 1, and the diagonal line is the diameter of the circumscribed circle of the hexagon); shearing a silicone rubber tube with the diameter of 2mm into a plurality of upright posts 2 with the length of 10 mm;

4) Fixing the manufactured upright post 2 on the surface of the lower layer silicon rubber film 1 by using tweezers according to the pre-layout requirement, then fixing the hexagonal discrete type blocking element 3 on the upright post 2, sealing the top of the upright post 2 by using a silicon rubber adhesive, and coating the adhesive on the periphery of the outer surface of the upright post 2 to form a ring so as to prevent the discrete type blocking element 3 from falling;

5) Arranging a vacuum tube 4 on the surface of the lower-layer silicon rubber film 1, wherein one end of the vacuum tube 4 is positioned on the lower-layer silicon rubber film 1, the end part is positioned outside the edgemost upright post 2, the other end of the vacuum tube is connected with a vacuum pump, then covering the prepared upper-layer silicon rubber film 5, and pressing the edge for sealing to obtain the skin III to be prepared;

6) And (4) carrying out air tightness test on the prepared skin, and filling the skin by using an injector filled with silicon rubber if the skin leaks.

Through the air tightness test of the skin-skin tee joint prepared in the experiments 1 to 3, as can be seen from fig. 5, the blocking element is hexagonal PET, compared with the circular blocking element and the rectangular blocking element, the hexagonal PET has high space utilization rate and is similar to a honeycomb structure, so that the overlapping area between blocking layers is largest, and the skin rigidity changing effect is best.

Different negative pressures are applied to the first skin, as can be seen from fig. 6, the greater the negative pressure, the better the rigidity-changing effect is, and the effect is stable until the pressure reaches-80 KPa.

As shown in fig. 7, the skin has certain flexibility in an atmospheric pressure state, and can be reversibly stretched in multiple directions, bent and folded; as shown in fig. 8, after a given shape, the skin is activated one, the stiffness is increased, the skin one can resist the force of deformation, the given 3D shape is maintained, and can be used as some functional tools, such as temporary liquid containers, the skin with an effective area of 130 x 130 mm-a sphere with a maximum envelopable diameter of 80 mm; and as shown in fig. 9, the skin can adapt to objects with different contours, keeps the contours unchanged after being activated, has certain bearing capacity, and shows better conformability and rigidity.

Claims

1. The utility model provides a 3D variable deformation rigidity covering based on laminar flow blocks up mechanism, its characterized in that includes lower floor's silicon rubber membrane (1), a set of stand (2), a set of discrete block up component (3), vacuum tube (4) and upper silicone rubber membrane (5), the lower floor's silicon rubber membrane (1) is equipped with a set of stand (2) on the surface, and the cover is equipped with a plurality of layers of discrete block up component (3) on every stand (2), and wherein multilayer discrete block up component (3) has constituted plugging layer (6), the one end of vacuum tube (4) sets up on lower floor's silicon rubber membrane (1), and its other end and vacuum pump connection, upper silicone rubber membrane (5) cladding is sealed on lower floor's silicon rubber membrane (1).

2. 3D variable deformational stiffness skin according to claim 1, in which the discrete occlusion elements (3) are hexagonal, circular or rectangular in shape and are made of PET.

3. The preparation method of the 3D variable deformation stiffness skin based on the laminar flow blockage mechanism as claimed in claim 1, characterized by comprising the following steps:

1) Respectively manufacturing a first mold of the lower silicone rubber film (1) and a second mold of the upper silicone rubber film (5) by a laser cutting processing method according to a preset skin size, and reserving after manufacturing;

2) Manufacturing the upright post (2) and the discrete plugging element (3) for standby;

3) Pouring the two silicon rubbers into a beaker, stirring and mixing the silicon rubbers by using a glass rod, putting the beaker into a vacuum drying oven for vacuumizing after the silicon rubbers are fully mixed until no bubbles emerge from the beaker, slowly pouring the mixture into the first mold and the second mold which are manufactured in the step 1) until the mixture reaches the edge, then placing the two molds on a flat surface for curing, and obtaining a lower silicon rubber film (1) and an upper silicon rubber film (5) after the curing is finished for later use;

4) Fixing the upright post (2) manufactured in the step 2) on the surface of the lower-layer silicon rubber film (1) prepared in the step 3) by using tweezers according to the requirement of pre-layout, then fixing the discrete plugging element (3) manufactured in the step 2) on the upright post (2), and sealing the top of the upright post (2) by using a silicon rubber adhesive;

5) After the step 4) is finished, arranging a vacuum tube (4) on the surface of the lower silicone rubber film (1), covering the upper silicone rubber film (5) prepared in the step 3), and pressing the edge for sealing to obtain the skin to be prepared;

6) And (5) carrying out air tightness test on the skin prepared in the step 5).

4. The method according to claim 3, wherein the first mold and the second mold in step 1) have the same structure and are transparent molds.

5. The method according to claim 3, wherein the step 2) is specifically performed by: cutting PET into a plurality of discrete blocking elements (3) by a laser cutting machine; the silicone rubber tube is cut into a plurality of upright posts (2) with the length of 10 mm.

6. The production method according to claim 3, characterized in that the volume ratio of the two silicone rubbers in the 3) step is 1; placing the two fully mixed silicon rubbers under the negative pressure condition of-0.1 MPa for 2-3 minutes until no bubbles emerge from the beaker; and the material in the first die and the second die is cured for 7 hours.

7. A method according to claim 3, characterized in that in step 4) a ring is formed by applying an adhesive around the outer surface of the pillar (2).

8. A method according to claim 3, characterized in that in step 5) one end of the vacuum tube (4) is located on the lower silicone rubber membrane (1) and outside the most peripheral pillar (2).

9. The method of claim 3, wherein in step 6), if the skin leaks, the skin is filled with a syringe containing silicone rubber.