阅读说明：本技术 基于触觉形状感知的柔性机械手及触觉形状感知装置 (Flexible manipulator based on touch shape sensing and touch shape sensing device ) 是由 梁斌 尹向辉 李寿杰 王学谦 于 2021-09-14 设计创作，主要内容包括：一种基于触觉形状感知的柔性机械手及触觉形状感知装置,该柔性机械手包括弹性软囊和摄像机,弹性软囊内充有透明流体介质,表面均匀分布有角度感知靶标,角度感知靶标包括微透镜阵列和位于微透镜阵列下方的图案层,微透镜阵列中的微透镜和图案层中的图案对应地构成多个靶点,当弹性软囊接触到物体时,柔性薄膜变形,角度感知靶标中的靶点随之发生相应的角度变化,由此所带来的靶点图案的变化由摄像机拍摄捕捉,其中,根据靶点图案的变化确定靶点的角度变化,进而确定物体的形状,柔性机械手根据所确定的物体形状进行物体抓取。本发明为机械手提供了一种触觉形状感知反馈机制,尤其可以帮助机器人在视觉受限情况下建立对环境、被操作物的感知。(A flexible mechanical arm based on touch shape perception and a touch shape perception device are provided, the flexible mechanical arm comprises an elastic soft bag and a camera, a transparent fluid medium is filled in the elastic soft bag, angle perception targets are uniformly distributed on the surface of the elastic soft bag, the angle perception targets comprise a micro lens array and a pattern layer located below the micro lens array, a plurality of target points are correspondingly formed by micro lenses in the micro lens array and patterns in the pattern layer, when the elastic soft bag contacts an object, a flexible film deforms, the target points in the angle perception targets correspondingly change in angle, and therefore the change of the brought target point patterns is shot and captured by the camera, wherein the angle change of the target points is determined according to the change of the target point patterns, the shape of the object is further determined, and the flexible mechanical arm captures the object according to the determined shape of the object. The invention provides a tactile shape perception feedback mechanism for a manipulator, and particularly can help the robot to establish perception of the environment and an operated object under the condition of limited vision.)

1. A flexible mechanical arm based on tactile shape perception is characterized by comprising an elastic soft bag and a camera, wherein the elastic soft bag comprises a flexible thin film forming a bag body, a transparent fluid medium is filled in the elastic soft bag, angle perception targets are uniformly distributed on the surface of the flexible thin film, the angle perception targets comprise a micro-lens array and a pattern layer positioned below the micro-lens array, a plurality of target points are correspondingly formed by micro-lenses in the micro-lens array and patterns in the pattern layer, when the elastic soft bag is in contact with an object, the flexible thin film deforms, the target points in the angle perception targets correspondingly change in angle, and therefore the change of the target point patterns is shot and captured by the camera, the angle change of the target points is determined according to the change of the target point patterns, and the shape of the object is further determined, and the flexible manipulator carries out object grabbing according to the determined object shape.

2. The compliant manipulator according to claim 1, wherein a microlens in said microlens array corresponds to a pixelet in said patterned layer, each pixelet comprising 3-4 pixels, and wherein only one of said pixels of light exits from the corresponding microlens at each angle.

3. The flexible manipulator according to claim 1, wherein the pattern layer includes a plurality of central dots, the central dots are formed in a contrasting color with a surrounding background, positions of the central dots change when angles change, and coordinates of the central positions of the central dots are obtained by processing the photographed images, thereby determining the angle change of the target point.

4. The flexible manipulator of claim 1, wherein the angle-aware target provides an angularly variable pattern.

5. The flexible manipulator according to any one of claims 1 to 4, wherein the elastic soft capsule is filled with a transparent mixed liquid of solid particles and liquid, the liquid in the elastic soft capsule is pumped out when an object is grabbed, a particle aggregation effect is generated, the solid particles are blocked and agglomerated, the shape of the elastic soft capsule is adaptively changed according to the surface shape of the object, and the object is clamped through the blocking and agglomerating action of the solid particles, so that the object grabbing is realized.

6. A variable stiffness flexible jaw according to claim 5 wherein the solid particles are mixed with a liquid to form a suspension having a density similar to water, from 0.9 to 1.1g/cm³Preferably 1.03g/cm³。

7. A variable stiffness flexible jaw according to claim 6 wherein the solid particles are a polydodecalactam material and the liquid is a NaCl or sugar water solution; preferably, the NaCl solution comprises 0.9 parts NaCl and 100 parts water by weight; preferably, the solid-liquid mixture is formed by mixing 50 to 80 parts of the solid particles and 100 parts of the NaCl solution.

8. The flexible manipulator according to any one of claims 1 to 4, further comprising a mechanical gripper for performing gripping, wherein the transparent fluid medium is a transparent gas or a transparent liquid.

9. The flexible manipulator according to claim 8, wherein the elastic bladder is disposed at a center of the flexible manipulator as a manipulator palm, and the mechanical jaws are disposed at side edges of the elastic bladder.

10. A tactile shape sensing device is characterized by comprising an elastic soft bag and a camera, wherein the elastic soft bag comprises a flexible film forming a bag body, the elastic soft bag is filled with a transparent fluid medium, angle sensing targets are uniformly distributed on the surface of the flexible film, the angle sensing targets comprise a micro-lens array and a pattern layer positioned below the micro-lens array, the micro-lenses in the micro-lens array and the patterns in the pattern layer correspondingly form a plurality of target points, when the elastic soft bag contacts an object, the flexible film deforms, the target points in the angle sensing targets correspondingly change in angle, and therefore the change of the target point patterns is shot and captured by the camera, wherein the angle change of the target points is determined according to the change of the target point patterns, and the shape of the object is further determined.

Technical Field

The invention relates to a robot grabbing technology, in particular to a flexible manipulator based on touch shape sensing and a touch shape sensing device.

Background

Perception, grabbing and operation in a vision-limited environment are always difficult points in the field of robots, but have great application prospects in the field of special robots. Under the environment of mud, oil and the like, the touch sense becomes the only accurate environment perception mode under the condition that optical equipment such as a camera, a laser radar and the like can not be used at all. Under the environment of deep water, caves, pipelines and the like, the visual field of the optical equipment is limited and is interfered by turbid suspended matters, dust and the like, the optical equipment is difficult to play a role to the maximum extent, and the touch sense is the most reliable environment sensing mode. When the manipulator grabs, the feedback of the tactile sense provides necessary information for the closed-loop control of the grabbing behavior.

Traditional touch sensor relies on fiber grating, array flexible pressure drag or capacitive sensor etc. and the price is expensive fragile, is difficult to use under various operating modes, also is not good to the great shape sensing effect of deformation.

A touch perception scheme is characterized in that black array points are arranged on a planar silicone membrane, three LED lamps with different colors are arranged on the periphery of the silicone membrane, when the silicone membrane does not contact an object, the three lamp colors are mixed to be white, when the silicone membrane contacts the object, due to deformation of the thin film, the thin film protruding inwards is irradiated by the LED lamps in the corresponding direction, therefore, color change is imaged by a rear camera, stress change can be obtained by analyzing the color, in addition, the change of black spot positions is recorded, and the shape of the contact object can be obtained by analyzing the change of the spot positions. Because three LED lamps on the periphery are required to glancing over the silicone membrane, the illumination is not uniform when no object is in contact, and the marked black points on the silicone membrane are also required to be in uniform array when no object is in contact, so that the silicone membrane is required to be completely flat, the silicone membrane is thick, the hardness is high, the size is small, and only small objects or textures can be detected.

The other tactile manipulator scheme adopts a particle aggregation clamping jaw, the clamping jaw consists of a soft outer coating ball and small particles inside, when an object is clamped, the outer coating ball forms the shape of the surface of the object, at the moment, the internal air is pumped, and the shape of the small particles inside is fixed after aggregation. The shape of the grasped object can be obtained by external laser scanning the outer shape of the outer cladding ball. The object is taken down after the object is required to be grabbed, and the surface information of the object is acquired through external laser scanning, so that the method is not practical in practice, the detection period is long, and the laser scanning cost is high.

It is to be noted that the information disclosed in the above background section is only for understanding the background of the present application and thus may include information that does not constitute prior art known to a person of ordinary skill in the art.

Disclosure of Invention

The main purpose of the present invention is to overcome the above-mentioned drawbacks of the background art, and to provide a flexible manipulator based on tactile shape sensing and a tactile shape sensing device.

In order to achieve the purpose, the invention adopts the following technical scheme:

a flexible manipulator based on touch shape perception comprises an elastic soft capsule and a camera, wherein the elastic soft capsule comprises a flexible film forming a capsule body, the elastic soft bag is filled with transparent fluid medium, the surface of the flexible film is uniformly distributed with angle sensing targets, the angle perception target comprises a micro lens array and a pattern layer positioned below the micro lens array, the micro lenses in the micro lens array and the pattern in the pattern layer correspondingly form a plurality of target points, when the elastic soft bag contacts an object, the flexible film deforms, the target point in the angle perception target correspondingly changes in angle, and the change of the target point pattern is shot and captured by the camera, and the flexible manipulator is used for grabbing the object according to the determined shape of the object.

Further:

the micro-lenses in the micro-lens array correspond to one pixel set in the pattern layer, each pixel set comprises 3-4 pixel points, and only light of one pixel point is emitted from the corresponding micro-lens at each angle.

The pattern layer comprises a plurality of central dots, the central dots and the surrounding background form contrasting colors, the positions of the central dots are changed when the angles are changed, and the center position coordinates of the central dots are obtained by processing the shot images, so that the angle change of the target point is determined.

The angle sensing target provides an angularly variable pattern.

The elastic soft bag is filled with transparent mixed liquid of solid particles and liquid, when an object is grabbed, the liquid in the elastic soft bag is pumped out to generate a particle aggregation effect, so that the solid particles block and agglomerate, the shape of the elastic soft bag is self-adaptively changed according to the surface shape of the object, and the object is clamped through the blocking and agglomeration effect of the solid particles, so that the object is grabbed.

The solid particles and the liquid are mixed into a suspension with the density similar to that of water, and the density is 0.9-1.1g/cm³Preferably 1.03g/cm³。

The solid particles are polydodecalactam materials, and the liquid is NaCl solution or sugar water solution; preferably, the NaCl solution comprises 0.9 parts NaCl and 100 parts water by weight; preferably, the solid-liquid mixture is formed by mixing 50 to 80 parts of the solid particles and 100 parts of the NaCl solution.

The device also comprises a mechanical clamping jaw for grabbing, and the transparent fluid medium is transparent gas or transparent liquid.

The elastic soft bag is arranged at the center of the flexible manipulator as a manipulator palm, and the mechanical clamping jaw is arranged at the side edge of the elastic soft bag.

A tactile shape sensing device comprises an elastic soft bag and a camera, wherein the elastic soft bag comprises a flexible film forming a bag body, the elastic soft bag is filled with a transparent fluid medium, angle sensing targets are uniformly distributed on the surface of the flexible film, the angle sensing targets comprise a micro lens array and a pattern layer positioned below the micro lens array, a plurality of target points are correspondingly formed by micro lenses in the micro lens array and patterns in the pattern layer, when the elastic soft bag contacts an object, the flexible film deforms, the target points in the angle sensing targets correspondingly change in angle, and therefore the change of the target point patterns brought by the change of the target point patterns is shot and captured by the camera, wherein the angle change of the target points is determined according to the change of the target point patterns, and the shape of the object is further determined.

The invention has the following beneficial effects:

the invention provides a flexible manipulator with a shape sensing function based on touch sensing, wherein a touch shape sensing device comprises an elastic soft bag filled with a transparent fluid medium, an angle sensing target comprising a micro-lens array and a pattern layer is arranged on the elastic soft bag, when the elastic soft bag contacts an object, the shape of the soft bag is adaptively changed according to the surface shape of the object, a target point in the angle sensing target is correspondingly changed in angle, the angle information of the target point is obtained through a camera, and the shape of the contacted object can be fitted according to the angle of the target, so that the micro-lens array is used for correlating a visual signal with the angle change of the target point, the sensing of the shape of the object is realized, the manipulator is suitable for being used under most vision-limited working conditions, is suitable for detecting complex shapes or environments, and is low in cost and easy to produce.

The invention provides a tactile shape perception feedback mechanism for the manipulator, and through tactile shape perception, the invention can especially help the robot to establish perception on environment and operated objects under the condition of limited vision (such as no light, mud, smoke and the like), is beneficial to perceiving larger shapes, and can also help the manipulator to adjust posture or grabbing force during grabbing.

Compared with other touch sensors, the touch sensor has the advantages of simple structure, low cost and easiness in manufacturing.

In a preferred scheme, the elastic soft bag is filled with a transparent mixed liquid of solid particles and liquid, and can also serve as a clamping jaw while the shape of the object is sensed by utilizing the particle aggregation blocking effect generated when the liquid is extracted. The flexible clamping jaw based on the blockage of the solid-liquid mixture particles achieves the purpose of flexible clamping by changing the rigidity of the clamping jaw through changing the liquid content, and is particularly suitable for grabbing objects with complicated shapes and surface characteristics. The size and complexity of the flexible manipulator is also reduced since this solution does not require additional mechanical jaws.

Drawings

FIG. 1a is a schematic structural diagram of a tactile shape sensing device according to an embodiment of the invention.

FIG. 1b is a diagram of a state of use of the tactile shape sensing device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of a variation of a microlens array display target in an embodiment of the present invention.

FIG. 3 is a schematic diagram of a target pattern and its variations in an embodiment of the invention.

Fig. 4 is a flexible manipulator based on tactile shape perception according to an embodiment of the invention.

Fig. 5 is a flexible manipulator based on tactile shape perception according to another embodiment of the invention.

Fig. 6 is a schematic diagram of the solid-liquid mixture of a variable stiffness flexible jaw based on solid-liquid mixture particle blocking according to an embodiment of the present invention.

Fig. 7a and 7b are schematic diagrams of the liquid extraction process of the variable-rigidity flexible clamping jaw based on the blockage of solid-liquid mixture particles in the embodiment of the invention.

Fig. 8a and 8b are schematic views of a single-capsule membrane jaw structure based on solid-liquid mixture particle blocking according to an embodiment of the invention.

Fig. 9a and 9b are schematic structural diagrams of a multi-elastic membrane sac clamping jaw based on solid-liquid mixture particle blocking according to another embodiment of the invention.

Detailed Description

The embodiments of the present invention will be described in detail below. It should be emphasized that the following description is merely exemplary in nature and is not intended to limit the scope of the invention or its application.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element. In addition, the connection may be for either a fixed or coupled or communicating function.

It is to be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for convenience in describing the embodiments of the present invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed in a particular orientation, and be in any way limiting of the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the embodiments of the present invention, "a plurality" means two or more unless specifically limited otherwise.

Referring to fig. 1a to 3, the embodiment of the invention provides a flexible manipulator based on tactile shape sensing, which includes an elastic soft capsule 1 and a camera 23, wherein the elastic soft capsule 1 includes a flexible film forming a capsule body, the elastic soft capsule 1 is filled with a transparent fluid medium 21, angle sensing targets 20 are uniformly distributed on the surface of the flexible film, the angle sensing targets 20 include a microlens array 24 and a pattern layer 25 located below the microlens array 24, microlenses in the microlens array 24 and patterns in the pattern layer 25 correspondingly form a plurality of target points, when the elastic soft capsule 1 contacts an object 3, the flexible film deforms, and corresponding angle changes occur in the angle sensing targets 20, so that the changes of the target point patterns are captured by the camera 23, wherein the angle changes of the target points are determined according to the changes of the target point patterns, and further determining the shape of the object, and grabbing the object by the flexible manipulator according to the determined shape of the object.

Referring to fig. 2, in some embodiments, the microlenses in the microlens array 24 correspond to a pixel set d in the pattern layer 25, each pixel set d includes 3-4 pixels, and only one pixel of light exits from the corresponding microlens at each angle.

Referring to fig. 3, in some embodiments, the pattern layer 25 includes a plurality of central dots 26, the central dots 26 are formed in a contrasting color with a surrounding background 27, the positions of the central dots 26 change when the angles change, and the center position coordinates of the central dots 26 are obtained by processing the photographed images, thereby determining the angle change of the target point.

In some embodiments, the angle sensing target 20 provides an angularly variable pattern.

Referring to fig. 4, in an embodiment, the flexible manipulator further includes a mechanical gripper 28 for gripping, and the transparent fluid medium in the elastic soft capsule 1 is transparent gas or transparent liquid 2'.

In a preferred embodiment, the elastic soft capsule 1 is arranged at the center of the flexible manipulator as a manipulator palm, the mechanical clamping jaws 28 are arranged at the side edges of the elastic soft capsule 1, and the camera 23 is fixed above the elastic soft capsule 1.

Referring to fig. 5 to 9b, in a preferred embodiment, the elastic soft bag 1 is filled with a transparent mixed liquid 2 of solid particles and liquid, when an object is grabbed, the liquid in the elastic soft bag 1 is pumped out to generate a particle aggregation effect, so that the solid particles are blocked and agglomerated, the shape of the elastic soft bag 1 is adaptively changed according to the surface shape of the object 3, and the object 3 is clamped through the blocking and agglomerating action of the solid particles, so that the object grabbing is realized. The elastic soft bag 1 of the embodiment can also be used as a clamping jaw while the shape of the object is sensed.

In a preferred embodiment, the solid particles are mixed with a liquid to form a suspension having a density similar to that of water, the density being between 0.9 and 1.1g/cm³Preferably 1.03g/cm³。

In a more preferred embodiment, the solid particles are a polydodecalactam material and the liquid is a NaCl or sugar water solution; preferably, the NaCl solution comprises 0.9 parts NaCl and 100 parts water by weight; preferably, the solid-liquid mixture is formed by mixing 50 to 80 parts of the solid particles and 100 parts of the NaCl solution.

Referring to fig. 1a to 3, the embodiment of the present invention further provides a tactile shape sensing device for the above flexible manipulator, which includes an elastic soft capsule 1 and a camera 23, wherein the elastic soft capsule 1 includes a flexible film forming a capsule body, the elastic soft capsule 1 is filled with a transparent fluid medium 21, an angle sensing target 20 is uniformly distributed on a surface of the flexible film, the angle sensing target 20 includes a microlens array 24 and a pattern layer 25 located below the microlens array 24, the microlenses in the microlens array 24 and the pattern in the pattern layer 25 correspondingly form a plurality of target points, when the elastic soft capsule 1 contacts an object, the flexible film deforms, and corresponding angle changes occur in the angle sensing target 20, and the resulting changes in the target point pattern are captured by the camera 23, and determining the angle change of the target point according to the change of the target point pattern, and further determining the shape of the object.

Specific embodiments of the present invention are further described below.

Angle perception target based on micro-lens array

As shown in fig. 1a and 1b, the angle sensing target 20 is made of a three-dimensional variable pattern slice including a microlens array 24, and is uniformly distributed and attached on the elastic soft capsule 1. When the flexible film of the elastic soft bag 1 is contacted with the object 3, the flexible film deforms, the angle of the target point on the film changes, the pattern on the target point changes and is received by the camera 23, the angle of the target point can be obtained according to the pattern, and the shape of the object 3 can be obtained through fitting.

FIG. 2 shows a schematic diagram of a variation of a microlens array display target in an embodiment of the present invention. The microlens array 24 is an optical element which forms a planar array 24 by using tiny lenses, when the pattern layer 25 is placed at the focal point of the microlens (distance r), the light of different points of the pattern layer 25 can be converted into light of different angles by the lenses, and therefore, the device displays different appearances when the observing directions are different. Here, the diameter D of the microlens is not smaller than the size of a pixel set D to be displayed on the pattern layer 25, and the pixel set includes a plurality of pixels, and only one pixel of light exits from one microlens at each angle. A typical conventional print pixel set may contain 3, 4 pixels. Microlens array 24 is known in the art as a dot 26 raster, but is not a raster concept, as may be used in the creation of stereographs.

FIG. 3 shows a target pattern and variations thereof in one embodiment of the invention. In a target pattern, a central dot 26 and a background 27 are formed in contrasting colors, the position of the central dot 26 changes when the angle changes, and the angle can be obtained by obtaining the coordinates of the central position through image processing. The target 20 may also take other patterns, or change color angularly, etc.

Flexible manipulator structure

Figure 4 illustrates a flexible manipulator based on tactile shape perception according to one embodiment of the invention. The scheme of the embodiment is that no solid is filled in the color-changing film, the elastic soft bag 1 is a palm of a manipulator, only provides a touch function, senses the size and the shape of a grasped object, and then is grasped by the mechanical clamping jaws 28 on the sides. The mechanical jaw 28 may be rigid or flexible.

Figure 5 illustrates a flexible manipulator based on tactile shape perception according to another embodiment of the invention. The manipulator structure of the embodiment uses the solid particle aggregation effect in the elastic soft capsule 1 for grasping.

In the latter embodiment, the flexible bladder 1 provides a variable stiffness flexible jaw structure based on solid-liquid mixture particle occlusion, and figures 6 to 7b illustrate the working principle of the flexible bladder 1. The elastic soft bag 1 is filled with a mixed liquid 2 of solid particles 201 and liquid 202, when an object 3 is clamped, the liquid 202 in the elastic soft bag 1 is pumped out, so that the solid particles 201 block and agglomerate, the shape of the elastic soft bag 1 is adaptively changed according to the surface shape of the object, and the object 3 is clamped through the blocking and agglomeration effect of the solid particles 201. As shown in fig. 7b, the clogged agglomerates of solid particles 201 are then shaped adaptively on the surface of the object 3, forming a shape 4 suitable for gripping the surface of the object.

In the invention, the variable-rigidity flexible clamping jaw structure provided by the elastic soft bag 1 utilizes the self-adaptive deformation of the solid-liquid mixture to clamp an object. The blocking of the particles means that a large number of particles form a large-area particle cluster under the action of external force, the particles in the particle cluster are stressed in balance, and the positions of the particles can be kept unchanged when the particles are subjected to certain external force. The particles are transformed from a loose state to a compact state and macroscopically present a liquid-to-solid phase transition-like process. As shown in fig. 6, the solid particles are mixed with the liquid, the solid particles are in a relatively loose state, and the density of the solid particles is consistent with that of the liquid, so that the mixture shows fluidity of the liquid in a certain space, and the shape can be changed according to the contact. In fig. 6 the object 3 is shown as a grid shape to represent a more complex contact surface. Figures 7a to 7b show the liquid extraction process based on a variable stiffness flexible jaw blocked by solid-liquid mixture particles.

Granular liquid mixed liquid

The following embodiments provide a solid-liquid mixture suitable for gripping objects using the principle of liquid driven particle jamming.

In some embodiments, the density of solid particles of the particle mixed liquid is consistent with that of the liquid, and is close to that of the water, so that the mixed liquid can suspend the solid particles in the liquid to achieve good fluidity, and simultaneously, the density of the mixed liquid is close to that of the water, so that the mixed liquid shows good flexibility in the water and can better change the shape to adapt to the surface structure of an object when the object is clamped.

In a preferred embodiment, the particles are nylon 12(PA12, polydodecalactam), which is suitable for the invention and has the advantage of a density of not more than 1.03g/cm³The material is the material with the density closest to that of water in common engineering plastics, and is the material with the lowest water absorption rate (0.25%) in the common engineering plastics, so that the material is very suitable for serving as particles of solid-liquid mixed liquid. The liquid adopts salt (NaCl) solution, the specific formula is that 0.9 part of salt by weight is mixed with 100 parts of water, and the density of the salt is 1.03g/cm³. 50 to 80 parts of solid particles are mixed with 100 parts of a salt solution to prepare a solid-liquid mixture.

Other materials may be used for the solid particles.

Other solutions may be used for the liquid, such as an aqueous sugar solution (which may be combined with higher density solid particles), and 8 parts of sucrose mixed with 100 parts of water may be used to form a solid-liquid mixture with nylon 12.

In actual preparation, the concentration of the solution can be calculated theoretically, or the particles can be put into a saturated solution and slowly added with water and stirred until the particles are suspended, or the particles can be put into water and slowly added with a solvent to be completely dissolved until the particles are suspended.

All the above formulations are effective at room temperature (around 20 ℃).

The proportion of the solid and the liquid can also change according to the practical application scene, and the given proportion integrates the fluidity and the change of the smaller volume of the solid particle group after the liquid is pumped away.

Different embodiments of flexible jaws

Referring to fig. 8a to 8b, in a preferred embodiment, the flexible clamping jaw with variable rigidity comprises a single elastic soft bag 1, a base 5, a pipeline 6 and a filter screen 7, wherein the base 5 is provided with a through hole, the elastic soft bag 1 is arranged on the base 5 and is communicated with the pipeline 6 through the through hole, the pipeline 6 is connected with a water pump (not shown), and the inlet of the elastic soft bag 1 is provided with the filter screen 7 for filtering the solid particles when the liquid is extracted; preferably, the elastic soft bag 1 is hemispherical; when the object is grabbed, the elastic soft bag 1 is pressed against the object 3, the liquid in the elastic soft bag 1 is pumped out through the pipeline 6, and solid particles in the elastic soft bag 1 are gathered to clamp the object 3.

Referring to fig. 9a to 9b, in another preferred embodiment, the flexible clamping jaw with variable rigidity comprises a plurality of flexible bags 1, each flexible bag 1 forms a clamping jaw finger, the flexible bags 1 comprise a liquid injection bag 101 and a liquid extraction bag 102, the liquid injection bag 101 is positioned on the side of the liquid extraction bag 102 opposite to the clamping direction, the liquid injection bag 101 is connected with a liquid injection pipe 103 for injecting liquid, the liquid extraction bag 102 is filled with a mixed liquid of the solid particles and the liquid, the liquid extraction bag 102 is connected with a liquid extraction pipe 104 and has a filtering structure for filtering the particles during liquid extraction, when an object needs to be clamped, the liquid injection pipe 103 is used for injecting the liquid into the liquid injection bag 101 to expand the liquid injection bag 101, the liquid in the liquid extraction bag 102 is extracted through the liquid extraction pipe 104 to contract the liquid extraction bag 102, and the clamping jaw hand bends towards the clamped object, the liquid injection bag 101 applies pressure to the liquid extraction bag 102, so that the liquid extraction bag 102 contacting the surface of the object is deformed into the shape of the surface of the object, and the object is clamped.

Referring to fig. 9 a-9 b, in a more preferred embodiment, the liquid extraction tube 104 extends through the liquid extraction bladder 102, the wall of the liquid extraction tube 104 is a porous structure capable of filtering particles, and the liquid extraction tube 104 is radially rigid and does not compress when liquid is extracted.

Referring to fig. 9a to 9b, in a more preferred embodiment, the flexible clamping jaw with variable stiffness further comprises a clamping jaw palm 8, and the clamping jaw palm 8 is configured as a bracket for fixing the root of the clamping jaw finger and the liquid injection pipe 103 and the liquid extraction pipe 104.

In different embodiments, the liquid in the liquid injection bag 101 and the liquid in the liquid pumping bag 102 are different liquids or the same liquid.

During the gripping, the liquid injection bag 101 may inject the liquid first, and then the liquid extraction bag 102 extracts the liquid, or both of them may be performed simultaneously.

The flexible clamping jaw of the embodiment, especially the flexible clamping jaw driven by liquid, is particularly suitable for being used in underwater environment for grabbing objects with complicated size, shape and surface characteristics. The flexible variability capability of the flexible clamping jaw can adaptively change the shape of the flexible clamping jaw to conform to a clamped object, and adaptively distribute the clamping force, thereby achieving the same effect of a complex closed-loop control mechanical clamping jaw with a sensor and a driver. The flexible clamping jaw can be made of low-cost materials and is simple to manufacture.

The invention provides a tactile shape perception feedback mechanism for the manipulator, which can help the manipulator to adjust the posture or the grabbing force during grabbing. As a tactile sensor, the robot can be helped to establish the perception of the environment and the operated object under the condition of limited vision (such as no light, mud, smoke and the like). Compared with other touch sensors, the touch sensor has the advantages of simple structure, low cost and easiness in manufacturing. The present invention is capable of sensing a larger shape than other tactile sensors.

The background of the present invention may contain background information related to the problem or environment of the present invention and does not necessarily describe the prior art. Accordingly, the inclusion in the background section is not an admission of prior art by the applicant.

The foregoing is a more detailed description of the invention in connection with specific/preferred embodiments and is not intended to limit the practice of the invention to those descriptions. It will be apparent to those skilled in the art that various substitutions and modifications can be made to the described embodiments without departing from the spirit of the invention, and these substitutions and modifications should be considered to fall within the scope of the invention. In the description herein, references to the description of the term "one embodiment," "some embodiments," "preferred embodiments," "an example," "a specific example," or "some examples" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Various embodiments or examples and features of various embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction. Although embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the scope of the claims.