Soft gripper and grasping robot

Abstract

The embodiment of the application provides a kind of software gripper and grabbing robot, belong to robot technical field, comprising: flexible suction cup and drive pump;The flexible suction cup includes intermediate connecting portion and multiple strip-shaped bending parts, multiple the bending parts are evenly spaced along the circumferential direction of the intermediate connecting portion;One side of the bending part is provided with multiple suction nozzles, multiple the suction nozzles are evenly spaced along the length direction of the bending part;The intermediate connecting portion and multiple the bending part inside hollow, and the intermediate connecting portion and multiple the bending part are communicated, multiple the suction nozzle and corresponding the bending part are communicated;Wherein, the drive pump is same in quantity with the suction nozzle, and the output end of each drive pump is respectively connected between each suction nozzle by hose, and the hose is distributed in the inside of the intermediate connecting portion and the bending part.The software gripper and grabbing robot provided by the embodiment of the application can improve the tactile ability of the software gripper, and then improve the grabbing ability of the software gripper.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of robots, in particular to a soft gripper and a grabbing robot. BACKGROUND

[0002] In order to make the robot hand have stronger controllability, safety and self-adaptive ability to various target objects (different sizes and shapes) in the process of interaction with the environment or human, the perception ability of the robot hand to the target object, especially in the case of lack of visual perception in turbid underwater environment, is worth studying.

[0003] The existing sensors include resistance sensors, capacitive sensors, piezoelectric sensors, and optical sensors, which are usually used for the perception of the target object by the robot grabbing hand, for example, combining a self-powered triboelectric thermal nanogenerator with a finger clamp, determining the bending position and bending angle of the object according to the change of voltage in the circuit, and thus inferring the size of the object. However, these mechanical and electronic components are difficult to work underwater for a long time, and therefore, how to directly generate tactile sensation in the water environment is one of the difficulties in the design of the grabbing hand. SUMMARY

[0004] Embodiments of the present application provide a soft gripper and a grabbing robot, aiming to improve the tactile ability of the soft gripper and thus improve the grabbing ability of the soft gripper.

[0005] The first aspect of embodiments of the present application provides a soft gripper, comprising:

[0006] a flexible suction cup and a driving pump;

[0007] The flexible suction cup comprises a middle connecting portion and a plurality of strip-shaped bending portions, and the plurality of bending portions are uniformly and spaced apart along the circumference of the middle connecting portion;

[0008] One side of the bending portion is provided with a plurality of suction nozzles, and the plurality of suction nozzles are uniformly and spaced apart along the length direction of the bending portion;

[0009] The middle connecting portion and the plurality of bending portions are hollow, and the middle connecting portion is in communication with the plurality of bending portions, and the plurality of suction nozzles are in communication with the corresponding bending portions;

[0010] The driving pump is the same in number as the suction nozzles, and the output end of each driving pump is connected with each suction nozzle through a hose, and the hose is distributed inside the middle connecting portion and the bending portion.

[0011] Optionally, the flexible suction cup further comprises a contact back film, which is arranged between the bending part and the suction nozzle, and is connected with the bending part, and the suction nozzle is connected with the bending part through the contact back film.

[0012] Optionally, the soft gripper further comprises a gripper frame, which is connected with the middle connecting part of the flexible suction cup.

[0013] Optionally, the soft gripper further comprises a driving device, which is fixed on the gripper frame and connected with the contact back film.

[0014] The driving device is used to deform the contact back film and drive multiple bending parts to bend at the same time, so as to wrap and grasp the target object.

[0015] Optionally, the driving device comprises a driving member and multiple connecting rod devices, and the driving member is arranged on the gripper frame.

[0016] The connecting rod device comprises a first connecting rod and a second connecting rod.

[0017] One end of the first connecting rod is provided with a connecting block, the first connecting rod is rotationally connected with the connecting block, and the connecting block is slidingly connected with the gripper frame in a direction perpendicular to the contact back film; the other end of the first connecting rod is connected with the contact back film.

[0018] One end of the second connecting rod is rotationally connected with the first connecting rod, and the other end is connected with the driving member.

[0019] The driving member is used to drive the second connecting rod to move towards the flexible suction cup, so as to drive the first connecting rod to move and rotate, and then drive the contact back film to deform and make multiple bending parts bend.

[0020] Optionally, multiple sliding grooves are arranged on the gripper frame, the sliding grooves extend in a direction perpendicular to the contact back film, and the connecting block is slidingly connected in the sliding grooves.

[0021] Optionally, multiple connecting ears are arranged on the contact back film, and the end of the first connecting rod is fixedly connected with the corresponding connecting ear.

[0022] Optionally, the driving member is a waterproof electric push rod.

[0023] Optionally, the soft gripper further comprises a connecting pipe, which is in communication with the middle connecting part, and the soft pipes connected with the multiple driving pumps and the multiple suction nozzles are located in the connecting pipe.

[0024] The second aspect of the embodiment of the present application provides a grabbing robot, which comprises the soft gripper provided in the first aspect of the embodiment of the present application.

[0025] Advantages:

[0026] The present application provides a soft gripper and a grabbing robot. The soft gripper comprises a flexible suction cup and a driving pump. The flexible suction cup comprises a middle connecting part and a plurality of curved parts. The curved parts are provided with a plurality of suction nozzles on one side. The middle connecting part and the curved parts are hollow and communicated. The number of the driving pumps is the same as the number of the suction nozzles. The output ends of the driving pumps are connected to the suction nozzles through hoses respectively. In this way, when the soft gripper is used, the suction nozzles can generate suction force by the driving pumps. When the soft gripper is adsorbed to an object, the flow changes of the suction nozzles covered by the object and the suction nozzles not covered by the object are different. Therefore, the size of the object can be distinguished according to the flow of each suction nozzle, and the tactile ability of the soft gripper is improved, so that the soft gripper can better grab the object. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the description of the embodiments of the present application will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0028] Figure 1 is a schematic diagram of the overall structure of a soft gripper according to an embodiment of the present application;

[0029] Figure 2 is a schematic diagram of the cross-sectional structure of a flexible suction cup in a soft gripper according to an embodiment of the present application;

[0030] Figure 3 is a schematic diagram of the structure of a connecting rod device in a soft gripper according to an embodiment of the present application;

[0031] Figure 4 is a schematic diagram of the structure of a soft gripper after the contact back film is deformed according to an embodiment of the present application.

[0032] Explanation of reference signs: 1, middle connecting part; 2, curved part; 3, suction nozzle; 4, contact back film; 41, connecting lug; 5, gripper frame; 51, sliding groove; 6, driving member; 7, connecting rod device; 71, first connecting rod; 72, connecting block; 73, second connecting rod; 8, connecting pipe. DETAILED DESCRIPTION

[0033] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are some of the embodiments of the present application, but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts are within the scope of the present application.

[0034] In the related art, the traditional rigid mechanical gripper is usually in rigid contact with the target object, and the pressure is applied through several points of contact to realize the grasping function by friction. This type of gripper has a simple structure and is generally used for grasping simple objects with regular shapes, but it is difficult to play an ideal role when facing irregular objects and cannot adapt to complex working conditions.

[0035] To mimic the soft properties of human hands, researchers have developed various types of soft grippers. For example, a human-like finger gripper is mainly made of silicone elastomer pouring, which drives the fingers to bend by transferring pressure to grasp objects, and has the advantages of low cost and easy manufacturing. By using multiple separate air chambers, more degrees of freedom can be added to such grippers, thereby improving the adaptability of the gripper to objects of different sizes and shapes; or by using materials with adjustable stiffness, the load capacity of such grippers can be improved. In addition to pump-driven, there are many driving methods for soft grippers in recent years, including chemical stimulation, electromagnetic, electroactive polymers, heat or light reaction. However, due to the fixed bending mode of the fingers and the characteristics of the discrete distribution of the fingers on the gripper, there is a gap between the contact and the target object, which may affect the stability of the grasping. There are disadvantages for grasping flat objects beyond the grasping range and small objects that are easy to slip from the finger gap.

[0036] In addition, the suction cup is a common attachment system widely used in industrial robots and can grasp a variety of workpiece products. However, the suction mode with only one gas passage will affect the versatility of the gripper. In contrast, the multi-modal fingerless flexible gripper can generate various grasping modes to adapt to the grasped objects, and can adaptively grasp the objects by deflating the air bag, or can grasp the planar objects by inflating the air bag and using its lip to suck the objects, but the suction mode is limited to relatively smooth surface flat objects.

[0037] In order to make the mechanical hand have stronger controllability, safety and adaptive ability to various target objects (different sizes and shapes) in the process of interaction with the environment or human, the perception ability of the robot hand to the target object, especially in the case of lack of visual perception in turbid underwater environment, is worth studying. The existing sensors include resistance sensors, capacitive sensors, piezoelectric sensors, and optical sensors, which are usually used for the perception of the target object by the robot hand. For example, a self-powered triboelectric thermal nanogenerator is combined with a finger clamp to determine the bending position and bending angle of the object according to the change of voltage in the circuit, so as to infer the size of the object. However, these mechanical and electronic components are difficult to work underwater for a long time, and therefore, how to directly generate touch in the water environment is one of the difficulties in the design of the grabbing hand.

[0038] Therefore, the embodiment of the present application proposes a soft grabbing hand and grabbing robot, which is provided with a flexible suction cup and a driving pump. The flexible suction cup comprises a middle connecting part and a plurality of bending parts. The bending parts are provided with a plurality of suction nozzles on one side. The middle connecting part and the bending parts are hollow and communicate with each other. The number of driving pumps is the same as the number of suction nozzles. The output end of each driving pump is connected with each suction nozzle through a hose. In this way, when the soft grabbing hand is used, a plurality of driving pumps can be used to generate suction force on each suction nozzle. When adsorbed to the object, the flow changes of the suction nozzles covered by the object and the suction nozzles not covered by the object are different. Therefore, the size of the object can be distinguished according to the flow of each suction nozzle, and the touch ability of the soft grabbing hand is improved, so that the soft grabbing hand can better grab the object.

[0039] Referring to Figure 1 The soft grabbing hand disclosed by the embodiment of the present application comprises a flexible suction cup and a driving pump.

[0040] Specifically, the flexible suction cup comprises a middle connecting part 1 and a plurality of strip-shaped bending parts 2. The plurality of bending parts 2 are uniformly and spaced apart along the circumference of the middle part. The middle connecting part 1 and the bending parts 2 are made of elastic materials, such as silica gel, rubber, TPU, etc., so that the flexible suction cup can produce certain deformation. The number of bending parts 2 can be 2-12, such as 2, 4, 6, 8, etc.

[0041] Referring to Figure 2 A plurality of suction nozzles 3 are provided on one side of the bending part 2. The plurality of suction nozzles 3 are uniformly and spaced apart along the length direction of the strip-shaped bending part 2. The shape of the suction nozzle 3 can be funnel-shaped. The number of suction nozzles 3 can be 1-5, such as 1, 2, 3, 4, 5, etc. The middle connecting part 1 and the plurality of bending parts 2 are hollow, and the middle connecting part 1 communicates with the plurality of bending parts 2. The plurality of suction nozzles 3 communicate with the corresponding bending parts 2.

[0042] Meanwhile, in the embodiment of the present application, the number of driving pumps (not shown in the figure) is the same as and corresponds to the number of suction nozzles 3 on the flexible suction plate. The output end of each driving pump is connected to each suction nozzle 3 through a hose (not shown in the figure) distributed in the intermediate connecting part 1 and the bending part 2, so that each driving pump can drive each individual suction nozzle 3 to generate suction force.

[0043] Therefore, when the soft gripper is used to grab underwater objects, the suction nozzles 3 can generate suction force to adsorb the objects to be grabbed. It can be understood that when the suction nozzles 3 generate suction force, water will also be sucked in at the same time, thereby generating flow at the position of the suction nozzles 3 (i.e., the flow size is not zero). After the suction nozzles 3 are adsorbed to the objects, the objects will cover the suction nozzles 3, and at this time the position of the covered suction nozzles 3 cannot generate flow (i.e., the flow size is zero). In the embodiment of the present application, each suction nozzle 3 is connected to a corresponding individual driving pump, and thus the size of the grabbed object can be determined according to the flow condition at the position of each suction nozzle 3, so that the soft gripper has a certain tactile ability, which can make the soft gripper better grab objects in a relatively turbid underwater environment. Meanwhile, connecting each suction nozzle 3 to a driving pump separately can prevent the leakage of pump suction force, achieve greater suction force, and thus achieve a more secure adsorption effect.

[0044] It should be noted that the flow change at the position of each suction nozzle 3 can be determined by the working state of each driving pump.

[0045] Further, as shown in Figure 1 The soft gripper further includes a contact back film 4 and a gripper frame 5. The contact back film 4 is arranged between the bending part 2 and the suction nozzles 3, and the contact back film 4 is connected to the bending part 2, and the suction nozzles 3 pass through the contact back film 4 and are connected to the bending part 2. The contact back film 4 can be fixed to the bending part 2 by adhesion, and the radius of the contact back film 4 is greater than or equal to the length of the bending part 2, so that the contact back film 4 can completely cover all the suction nozzles 3. The contact back film 4 can be made of the same elastic material as the flexible suction plate, such as silicone, rubber, TPU, etc.

[0046] The gripper frame 5 is fixedly connected to the intermediate connecting part 1 of the flexible suction plate, and the gripper frame 5 can facilitate the connection of the soft gripper to the grabbing robot.

[0047] In an alternative embodiment, the present application further provides a soft gripper, which comprises a driving device fixed to the gripper frame 5 and connected to the contact back film 4. The driving device is used to deform the contact back film 4 and drive the plurality of bending parts 2 to bend at the same time, so as to wrap and grab the target object.

[0048] Specifically, referring to Figure 1As shown, the driving device comprises a driving member 6 and a plurality of linkage devices 7. The driving member 6 can be fixed on the gripper frame 5.

[0049] Referring to Figure 1 and Figure 3 As shown, the linkage device 7 comprises a first linkage 71 and a second linkage 73. In order to better deform the contact back film 4, the first linkage 71 is in the shape of a whole arc. One end of the first linkage 71 is provided with a connecting block 72, and the first linkage 71 is rotatably connected with the connecting block 72, while the connecting block 72 is slidably connected on the gripper frame 5 in a direction perpendicular to the contact back film 4. It should be noted that the contact back film 4 in the direction perpendicular to the contact back film 4 herein refers to the contact back film 4 in a flat state without deformation. The other end of the first linkage 71 (i.e. the end away from the connecting block 72) is fixedly connected with the contact back film 4.

[0050] One end of the second linkage 73 is rotatably connected with the first linkage 71, and the other end is rotatably connected with the driving member 6. The position where the second linkage 73 is rotatably connected with the first linkage 71 is located near the connecting block 72 of the first linkage 71. The position where the second linkage 73 is connected with the first linkage 71 can determine the angle of rotation of the first linkage 71, which can be adjusted according to actual needs by those skilled in the art, and therefore will not be described here.

[0051] Further, referring to Figure 4 As shown, the driving member 6 can drive the second linkage 73 to move towards the flexible suction cup, so that the second linkage 73 drives the first linkage 71 to move towards the flexible suction cup and rotate towards the gripper frame 5, and the first linkage 71 is connected with the contact back film 4, so that the first linkage 71 can drive the contact back film 4 to deform in a direction away from the bending part 2, and drive the bending part 2 to bend in a direction away from the gripper frame 5, so that the contact back film 4 can wrap and grasp the object. When the driving member 6 drives the second linkage 73 to move in a direction away from the flexible suction cup, the second linkage 73 can drive the first linkage 71 to move in a direction away from the flexible suction cup, so that the contact back film 4 returns to a flat state.

[0052] In this way, the contact back film 4 of the soft gripper can wrap the object, and thus realize the grasping of the object. Meanwhile, based on the above structure, the soft gripper provided by the embodiments of the present application has three grasping modes.

[0053] First, a single suction force grasping mode, in which the driving member 6 does not work, and only the suction nozzle 3 generates suction force to adsorb the object by driving the pump, so as to realize the grasping of the object.

[0054] Second, the single suction cup closed grabbing, in this mode, the driving pump does not work, only through the driving member 6 drives the connecting rod device 7 to deform, and then drives the contact back film 4 to deform, so that the whole flexible suction cup wraps the object, thereby realizing the grabbing of the object.

[0055] Third, the mixed grabbing mode, in this mode, the driving pump and the driving member 6 work simultaneously, that is, in the case that the flexible suction cup wraps the object, the object is further adsorbed through the suction force of the suction nozzle 3, so that the soft gripper can better grab the object.

[0056] Through the above different grabbing modes, the soft gripper can grab objects of various shapes (planar or non-planar) and sizes, scattered objects, living organisms (turtles and goldfish), overweight objects and objects beyond the grabbing range, etc., and can be used in air and underwater amphibious.

[0057] Further, in order to facilitate the underwater use of the soft gripper, the driving member 6 can be selected as a waterproof electric push rod. The gripping frame is provided with an accommodation area for accommodating the waterproof electric push rod, so that the waterproof electric push rod can better move towards the flexible suction cup, and a plurality of strip-shaped holes are also formed on the gripping frame, and the second connecting rod 73 is connected with the waterproof electric push rod through the corresponding strip-shaped hole.

[0058] Further, as shown in Figure 1 , a plurality of sliding grooves 51 are arranged on the gripping frame, the sliding grooves 51 extend along the direction perpendicular to the contact back film 4, and the connecting block 72 is slidingly connected in the corresponding sliding groove 51, so that the sliding connection between the connecting block 72 and the gripping frame is realized, and the connecting block 72 can better slide along the direction perpendicular to the contact back film 4. Of course, in some optional embodiments, a sliding rail can also be arranged on the gripping frame to realize the sliding connection between the connecting block 72 and the gripping frame.

[0059] Further, as shown in Figure 1 , a plurality of connecting ears 41 are arranged on the contact back film 4, and the end of the first connecting rod 71 is fixedly connected with the corresponding connecting ear 41.

[0060] In an optional embodiment, as shown in Figure 1 , the embodiment of the application further provides a soft gripper, which comprises a connecting pipe 8, one end of the connecting pipe 8 is communicated with the intermediate connecting part 1, and the other end can extend to the position where the driving pump is located. The soft pipes connected with the plurality of driving pumps and the plurality of suction nozzles 3 are all located in the connecting pipe 8. The soft pipes can be better protected through the connecting pipe 8.

[0061] Based on the same inventive concept, the embodiment of the application discloses a grabbing robot, which comprises any soft gripper provided by the embodiment of the application.

[0062] It should be noted that each of the embodiments in the present specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the embodiments can be mutually referred to.

[0063] It should also be noted that in this paper, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations, nor can it be understood as indicating or implying relative importance. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or terminal device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or terminal device. Without more limitations, the element defined by the statement "including a" does not exclude the presence of another identical element in the process, method, article or terminal device including the element.

[0064] The above describes the technical solutions provided by the present application in detail. The principles and implementation modes of the present application are described by applying specific examples. The above description of the embodiments is only to help understand the present application, and the content of the specification should not be understood as limiting the present application. Meanwhile, for those skilled in the art, according to the present application, there will be different forms of changes in specific implementation modes and application ranges, which do not need and cannot be exhaustively enumerated here, and the obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A soft gripper, characterized by, The soft body gripper comprises: a flexible suction cup and a driving pump; the flexible suction cup comprises a middle connecting part and a plurality of strip-shaped bending parts, the plurality of bending parts are uniformly spaced along the circumference of the middle connecting part; one side of the bending part is provided with a plurality of suction nozzles, the plurality of suction nozzles are uniformly spaced along the length direction of the bending part; the middle connecting part and the plurality of bending parts are hollow, and the middle connecting part and the plurality of bending parts are in communication, and the plurality of suction nozzles are in communication with the corresponding bending parts; wherein the driving pump is the same as the number of suction nozzles, and the output end of each driving pump is connected with each suction nozzle through a hose, and the hose is distributed in the inside of the middle connecting part and the bending part; the flexible suction cup further comprises: a contact back film, the contact back film is arranged between the bending part and the suction nozzle, the contact back film is connected with the bending part, and the suction nozzle is connected with the bending part through the contact back film; the soft body gripper further comprises: a gripper frame connected with the middle connecting part of the flexible suction cup; a driving device fixed on the gripper frame, and the driving device is connected with the contact back film; the driving device is used for deforming the contact back film and driving the plurality of bending parts to bend at the same time, so as to wrap and grab the target object; the driving device comprises: a driving member and a plurality of connecting rod devices, the driving member is arranged on the gripper frame; the connecting rod device comprises a first connecting rod and a second connecting rod; wherein one end of the first connecting rod is provided with a connecting block, the first connecting rod is rotatably connected with the connecting block, the connecting block is slidably connected with the gripper frame in a direction perpendicular to the contact back film; the other end of the first connecting rod is connected with the contact back film; one end of the second connecting rod is rotatably connected with the first connecting rod, and the other end is rotatably connected with the driving member; the driving member is used for driving the second connecting rod to move towards the flexible suction cup, so as to drive the first connecting rod to move and rotate, and then drive the contact back film to deform and make the plurality of bending parts bend.

2. The soft body gripper according to claim 1, wherein: a plurality of sliding grooves are arranged on the gripper frame and extend in a direction perpendicular to the contact back film, and the connecting block is slidably connected in the sliding groove.

3. The soft body gripper according to claim 1, wherein: a plurality of connecting ears are arranged on the contact back film, and the end of the first connecting rod is fixedly connected with the corresponding connecting ear.

4. The soft body gripper according to any one of claims 1-3, wherein: the driving member is a waterproof electric push rod.

5. The soft gripper of claim 1, wherein, the soft body gripper further comprises: a connecting pipe in communication with the middle connecting part, and the hoses connecting the plurality of driving pumps and the plurality of suction nozzles are located in the connecting pipe.

6. A grabbing robot, comprising the soft body gripper according to any one of claims 1-5. ​

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