A Variable-Friction Soft Hand Capable of Sensing Texture Shape and Its Grasping Method

Abstract

The present invention discloses a variable-friction soft hand capable of perceiving texture shape and a grasping method thereof. Among them, the variable-friction soft hand includes: a palm; a soft thumb mechanism connected to the palm, and the soft thumb mechanism can bend relative to the palm; a soft finger mechanism connected to the palm, and the soft finger mechanism can bend relative to the palm. In the present invention, the soft thumb mechanism bends relative to the palm, so that the soft thumb mechanism contacts the target for texture perception, and then the surface shape information of the target is obtained. Moreover, the soft finger mechanism can adjust its own friction force, so that the soft finger mechanism bends relative to the palm, so that the target is grasped by the soft finger mechanism and the soft thumb mechanism, or the target is grasped by the soft finger mechanism and the palm, improving the perception performance and adaptive performance of the target, thereby expanding the applicable range, and achieving the effects of protecting the target and improving the grasping stability of the target.

Description

Technical Field

[0001] The present invention relates to the field of soft robots, and in particular to a variable-friction soft hand capable of perceiving texture shapes and a grasping method thereof. Background Art

[0002] Soft robots are widely used in industries, agriculture, medical treatment, military and other fields due to their flexibility, safety, compliance and other characteristics. Soft robots are made of soft materials with a low Young's modulus, can adapt to special scenarios, and have broad application prospects.

[0003] Rigid dexterous hands are difficult to control the force during the grasping process and may cause damage to soft, fragile and irregular objects. Soft hands imitate the structure and function of human hands and directly contact people or objects with safer and more compliant materials in various operation tasks, so they have become an important research direction in the field of soft robots. With the continuous development of society, the application environments and scenarios faced by soft hands are becoming more and more complex, putting forward higher requirements for the perception ability and grasping ability of soft hands. In terms of perception, the current perception ability of soft hands mostly focuses on the state perception of the fingers themselves, such as bending, pressure, air pressure, etc., and it is difficult to perceive the texture shape of the grasped object; in terms of grasping, the current grasping ability of soft hands mostly relies on the bending of soft fingers and it is difficult to adapt to objects of different sizes, different materials and different surface roughnesses. Moreover, few studies have achieved grasping in complex scenarios by simultaneously improving the perception and grasping abilities of soft hands.

[0004] Therefore, the existing technology still needs to be improved and developed. Summary of the Invention

[0005] In view of the above deficiencies of the existing technology, the purpose of the present invention is to provide a variable-friction soft hand capable of perceiving texture shapes and a grasping method thereof, aiming to solve the technical problem that in the existing technology, the soft hand cannot adjust the friction force of the gripper according to the surface roughness of the object, resulting in a small applicable scenario range.

[0006] The technical solution of the present invention is as follows:

[0007] In a first aspect, the present invention provides a variable-friction soft hand capable of perceiving texture shapes, which includes:

[0008] A palm;

[0009] A soft thumb mechanism, connected to the palm, the soft thumb mechanism can bend relative to the palm, and is used for texture perception of the surface of a target to obtain surface shape information of the target;

[0010] A soft finger mechanism, connected to the palm, can bend relative to the palm, and is used to adjust the soft finger mechanism according to the surface shape information of the target to determine the corresponding friction information of the soft finger mechanism;

[0011] The soft finger mechanism and the soft thumb mechanism cooperate with each other and can be used to grasp the target according to the friction information corresponding to the soft finger mechanism and the surface shape information of the target.

[0012] In one embodiment, the variable-friction soft hand further includes:

[0013] An inflation device, respectively connected to the soft finger mechanism and the soft thumb mechanism, is used to control the bending degree of the soft finger mechanism and the soft thumb mechanism respectively, and control the friction information corresponding to the soft finger mechanism.

[0014] In one embodiment, the soft finger mechanism includes:

[0015] A finger actuation unit, provided with a plurality of finger bending air cavities and a plurality of airbag cavities;

[0016] A finger outer sleeve, which is arranged in a fitting manner with the outer wall of the finger actuation unit;

[0017] A plurality of airbag blocks, connected to the inner wall of the airbag cavity;

[0018] A plurality of friction modules, connected to the airbag blocks, are used to grasp the target;

[0019] Among them, the plurality of airbag cavities, the plurality of airbag blocks, and the plurality of friction modules correspond one by one. The finger bending air cavity and the airbag cavity are correspondingly arranged. The finger bending air cavity can be inflated to make the finger actuation unit bend correspondingly. The airbag block can be inflated, and the friction module can be slidably connected to the finger outer sleeve to determine the friction information corresponding to the soft finger mechanism.

[0020] In one embodiment, the soft thumb mechanism includes:

[0021] A thumb actuation unit, provided with a thumb bending air cavity;

[0022] A thumb outer sleeve, which is arranged in a fitting manner with the outer wall of the thumb actuation unit;

[0023] A rotation module, provided with a rotation bending air cavity;

[0024] A visual and tactile sensor, arranged on the thumb outer sleeve, is used to sense the texture of the surface of the target;

[0025] Wherein, the thumb actuating unit is connected to the thumb rotating module, the thumb bending air chamber and the rotating bending air chamber can be inflated to cause corresponding bending of the soft thumb mechanism, and the rotating module is rotatably connected to the palm.

[0026] In one embodiment, the strength of the finger outer sleeve is greater than that of the finger actuating unit, and the friction coefficient of the friction module is greater than that of the finger outer sleeve.

[0027] In one embodiment, the variable-friction soft hand further includes:

[0028] A base;

[0029] A soft wrist, connected to the base;

[0030] Wherein, the inflation device is connected to the soft wrist, the palm is connected to the soft wrist, and a plurality of adjustment air chambers are provided in the soft wrist. The adjustment air chambers can be inflated to cause corresponding bending of the palm, the soft finger mechanism and the soft thumb mechanism.

[0031] In one embodiment, the number of the finger bending air chambers and the airbag chambers is three each. The finger actuating unit and the finger outer sleeve are respectively provided with three corresponding first air holes and second air holes. The finger bending air chambers are communicated with the outside through the first air holes and the second air holes. The finger actuating unit and the finger outer sleeve are respectively provided with three corresponding third air holes and fourth air holes. The airbag chambers are communicated with the outside through the third air holes and the fourth air holes.

[0032] In one embodiment, the number of the soft finger mechanisms is set to four. The four soft finger mechanisms are respectively connected to the first mounting position, the second mounting position, the third mounting position and the fourth mounting position of the palm, and the soft thumb mechanism is connected to the fifth mounting position of the palm.

[0033] In a second aspect, the present invention provides a grasping method for a variable-friction soft hand capable of sensing texture and shape according to any one of the above solutions. Wherein, the method includes:

[0034] Controlling the soft thumb mechanism to sense the texture of the surface of the target to obtain the surface shape information of the target;

[0035] Adjusting the soft finger mechanism according to the surface shape information of the target to determine the friction force information corresponding to the soft finger mechanism;

[0036] Controlling the soft thumb mechanism and the soft finger mechanism to grasp the target according to the friction force information corresponding to the soft finger mechanism and the surface shape information of the target.

[0037] In one embodiment, the variable-friction soft hand further includes:

[0038] An inflation device, respectively connected to the soft finger mechanism and the soft thumb mechanism;

[0039] The surface shape information of the target includes the surface roughness information of the target and the shape contour information of the target;

[0040] Adjusting the soft finger mechanism according to the surface shape information of the target to determine the friction force information corresponding to the soft finger mechanism includes:

[0041] According to the surface roughness information of the target, controlling the inflation device to adjust the soft finger mechanism to determine the friction force information corresponding to the soft finger mechanism.

[0042] Beneficial effects: The present invention provides a variable-friction soft hand capable of perceiving texture shape and a grasping method thereof. Among them, the variable-friction soft hand includes: a palm; a soft thumb mechanism connected to the palm, and the soft thumb mechanism can bend relative to the palm; a soft finger mechanism connected to the palm, and the soft finger mechanism can bend relative to the palm. The present invention bends the soft thumb mechanism relative to the palm, so that the soft thumb mechanism contacts the target for texture perception, and then obtains the surface shape information of the target. Moreover, the soft finger mechanism can adjust its own friction force, so that the soft finger mechanism bends relative to the palm, so that the target is grasped by the soft finger mechanism and the soft thumb mechanism, or the target is grasped by the soft finger mechanism and the palm, improving the perception performance and adaptive performance of the target, further expanding the scope of application, and achieving the effects of protecting the target and improving the grasping stability of the target. Brief Description of the Drawings

[0043] Figure 1 It is a three-dimensional structure diagram of the variable-friction soft hand capable of perceiving texture shape of the present invention.

[0044] Figure 2 It is an exploded schematic diagram of the soft finger mechanism of the present invention.

[0045] Figure 3 It is a three-dimensional structure diagram of the soft finger mechanism of the present invention.

[0046] Figure 4 It is a front view of the soft finger mechanism of the present invention.

[0047] Figure 5 For the present invention Figure 4 The cross-sectional view at A-A.

[0048] Figure 6For the present invention Figure 4 Cross-sectional view taken along line B-B in [the figure].

[0049] Figure 7 Exploded view of the soft thumb mechanism of the present invention.

[0050] Figure 8 Stereoscopic structure diagram of the soft thumb mechanism of the present invention.

[0051] Figure 9 Front view of the soft thumb mechanism of the present invention.

[0052] Figure 10 For the present invention Figure 9 Cross-sectional view taken along line C-C in [the figure].

[0053] Figure 11 Stereoscopic structure diagram of the palm of the present invention from the first perspective.

[0054] Figure 12 Stereoscopic structure diagram of the palm of the present invention from the second perspective.

[0055] Figure 13 Exploded view of the base and the soft wrist of the present invention.

[0056] Figure 14 Cross-sectional view of the soft wrist of the present invention.

[0057] Figure 15 Flowchart of the grasping method of the variable-friction soft hand of the present invention.

[0058] Explanation of reference numerals:

[0059] 100, palm; 101, trachea fixing groove; 110, first mounting position; 120, second mounting position; 130, third mounting position; 140, fourth mounting position; 150, fifth mounting position; 200, soft finger mechanism; 210, finger actuation unit; 211, first air hole; 212, third air hole; 213, finger bending air cavity; 214, airbag cavity; 220, finger outer sleeve; 221, second air hole; 222, fourth air hole; 230, airbag block; 240, friction module; 300, soft thumb mechanism; 310, thumb actuation unit; 311, fifth air hole; 312, thumb bending air cavity; 320, thumb outer sleeve; 321, sixth air hole; 330, rotation module; 331, rotation bending air cavity; 340, rotation outer sleeve; 350, connecting piece; 360, visual and tactile sensor; 410, base; 420, soft wrist; 421, adjustment air cavity; 422, communication hole; 430, connecting piece. Detailed implementation manners

[0060] The present invention provides a variable-friction soft hand capable of perceiving texture shape and a grasping method thereof. To make the objectives, technical solutions, and effects of the present invention clearer and more explicit, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0061] It should be noted that when a component is referred to as "fixed to" or "disposed on" another component, it can be directly on the other component or indirectly on the other component. When a component is referred to as "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component.

[0062] It should also be noted that the same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", etc. indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings. This is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the drawings are only for illustrative purposes and cannot be understood as a limitation of this patent. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0063] Currently, the perception ability of soft hands mostly focuses on the perception of the state of the fingers themselves, such as bending, pressure, air pressure, etc., and it is difficult to perceive the texture shape of the grasped object; in terms of grasping, the grasping ability of current soft hands mostly relies on the bending of the soft fingers and it is difficult to adapt to objects of different sizes, different materials, and different surface roughnesses. Moreover, few studies have achieved grasping in complex scenarios by simultaneously improving the perception and grasping abilities of soft hands.

[0064] To solve the above problems, the present invention provides a variable-friction soft hand capable of perceiving texture shape, as Figure 1 shown, which includes:

[0065] A palm 100;

[0066] A soft thumb mechanism 300, connected to the palm 100, the soft thumb mechanism 300 can bend relative to the palm 100, and is used to perform texture perception on the surface of the target to obtain the surface shape information of the target;

[0067] A soft finger mechanism 200, connected to the palm 100, the soft finger mechanism 200 can bend relative to the palm 100, and is used to adjust the soft finger mechanism 200 according to the surface shape information of the target to determine the friction force information corresponding to the soft finger mechanism;

[0068] The soft finger mechanism 200 and the soft thumb mechanism 300 cooperate with each other and can be used to grasp the target according to the friction information corresponding to the soft finger mechanism and the surface shape information of the target.

[0069] It should be noted that the target is an object, the surface of the object is smooth or has different degrees of roughness, and the object can be an object with different sizes, materials, and surface roughnesses, which are not specifically limited here. Both the soft finger mechanism 200 and the soft thumb mechanism 300 have multiple joints, and the soft finger mechanism 200 and the soft thumb mechanism 300 can be bent at the joints respectively. In this embodiment, it is set with reference to the human palm. That is to say, there are four soft finger mechanisms 200, and each has three joints. There is one soft thumb mechanism 300, and it has two joints. It should be noted that there is also a rotatable module at the connection between the end of the thumb and the palm to simulate the grasping movement of the human hand; but it is not limited to this. The soft finger mechanism 200 and the soft thumb mechanism 300 can each have multiple joints, such as 4 or 5.

[0070] The soft finger mechanism 200 and the soft thumb mechanism 300 are made of materials that can be bent and can return to the initial state without external force, such as silicone and rubber.

[0071] In the present invention, the soft thumb mechanism 300 bends relative to the palm, so that the soft thumb mechanism 300 contacts the target for texture perception, and then the surface shape information of the target is obtained. Moreover, the soft finger mechanism 200 can adjust its own friction force, so that the soft finger mechanism 200 bends relative to the palm, so that the target is grasped by the soft finger mechanism and the soft thumb mechanism, or the target is grasped by the soft finger mechanism and the palm, improving the perception performance and adaptive performance of the target, and further expanding the scope of application, and achieving the effects of protecting the target and improving the grasping stability of the target.

[0072] In this embodiment, the variable-friction soft hand further includes:

[0073] An inflation device (not shown in the figure), which is respectively connected to the soft finger mechanism 200 and the soft thumb mechanism 300, and is used to control the bending degree of the soft finger mechanism 200 and the soft thumb mechanism 300 respectively, and control the friction information corresponding to the soft finger mechanism.

[0074] Specifically, the inflation device can be set as an air pump (not marked in the figure). It should be noted that the inflation device can be set on the palm 100, but is not limited thereto. A proportional valve is connected to the air pump. That is to say, the air pump is connected to the soft finger mechanism 200 and the soft thumb mechanism 300 respectively through the proportional valve. By controlling the magnitude of the control voltage of the proportional valve through the chip DA, the gas of the air pump can output a constant air pressure through the proportional valve, and then the bending degrees of the soft finger mechanism 200 and the soft thumb mechanism 300 can be controlled respectively. Moreover, the air pump can also control the friction force magnitude of the soft finger mechanism 200 through the proportional valve, so as to realize the adjustment of the friction force between the soft finger mechanism 200 and the object. It should be noted that a pressure relief port is provided on the proportional valve, and the gas filled into the soft finger mechanism 200 and the soft thumb mechanism 300 can be discharged respectively through the pressure relief port, so as to realize the reset operation of their bending degrees.

[0075] Further, the proportional valve is connected to the soft finger mechanism 200 and the soft thumb mechanism 300 through multiple air pipes. Through the adjustment of the proportional valve, the required gas is filled into each joint of the soft finger mechanism 200 and the soft thumb mechanism 300 through each air pipe, so as to realize the bending degree required for grasping an object. And the friction force change at the finger pulp of each joint of the soft finger mechanism 200 is realized through multiple air pipes (such as Figure 3 the right surface), so as to improve the grasping performance of smooth-surface objects and achieve the effect of reducing energy consumption.

[0076] In this embodiment, as Figures 2 to 6 shown, the soft finger mechanism 200 includes:

[0077] A finger actuation unit 210, which is provided with a plurality of finger bending air cavities 213 and a plurality of airbag cavities 214;

[0078] A finger outer sleeve 220, which is arranged in a fitting manner with the outer wall of the finger actuation unit 210;

[0079] A plurality of airbag blocks 230, which are connected to the inner wall of the airbag cavity 214;

[0080] A plurality of friction modules 240, which are connected to the airbag blocks 230 and are used for grasping the target;

[0081] Among them, the plurality of airbag cavities 214, the plurality of airbag blocks 230 and the plurality of friction modules 240 correspond one by one. The finger bending air cavities 213 and the airbag cavities 214 are arranged correspondingly. The finger bending air cavities 213 can be inflated to make the finger actuation unit 210 bend correspondingly. The airbag blocks 230 can be inflated. The friction modules 240 can be slidably connected to the finger outer sleeve 220 to determine the friction force information corresponding to the soft finger mechanism.

[0082] Specifically, as Figure 2 , Figure 5 and Figure 6 shown, the finger outer sleeve 220 is nested outside the finger actuation unit 210. The soft finger mechanism 200 has three joints. That is to say, the number of airbag cavities 214, airbag blocks 230, and friction modules 240 is three. The number of finger bending air cavities 213 can be the same as the number of friction modules 240 and is also set to three, but it is not limited to this. For example, the soft finger mechanism 300 has three adjustable joints (i.e., has three finger bending air cavities 213), and the friction module 240 with variable friction can be set to 2 or four. As Figure 5 or Figure 6 shown, the finger bending air cavities 213 are correspondingly arranged with the airbag cavities 214. That is to say, the three finger bending air cavities 213 and the three airbag cavities 214 are arranged at intervals, so that there is a friction module 240 that can change the friction of the soft finger mechanism at each bending joint, and their facing directions are opposite. Specifically, the openings of the finger bending air cavities 213 face the top surface of the finger actuation unit 210, and the openings of the airbag cavities 214 face the bottom surface of the finger actuation unit 210. Thus, through the finger bending air cavities 213 and the three airbag cavities 214 arranged at intervals, but it is not limited to this. The inflation device can also communicate with the finger bending air cavity through the side surface of the finger actuation unit 210.

[0083] Furthermore, the airbag block 230 is connected to the friction module 240 on the side close to the opening of the airbag cavity 214 (i.e., the bottom of the airbag block). In the initial state, the corresponding friction module 240 and airbag block 230 are embedded in the airbag cavity 214. That is to say, in the initial state, the bottom surface of the friction module 240 (such as Figure 3 the right side surface) is flush with the bottom surface of the finger actuation unit 210; after the airbag block 230 is inflated and expanded by the inflation device, it drives the friction module 240 connected to its bottom surface to move towards the bottom surface side of the finger actuation unit 210, so that the bottom surface of the friction module 240 extends out of the finger actuation unit 210, realizing the friction adjustment of the soft finger mechanism 200. As Figure 2 shown, the friction module 240 is in a "concave" shape, and the side end of the friction module 240 can also be slidably connected to the finger outer sleeve 220, and the concave surface of the friction module 240 can be abutted by the finger outer sleeve 220, so as to prevent the friction module 240 from detaching from the finger actuation unit 210.

[0084] In this embodiment, the strength of the finger outer sleeve 220 is greater than the strength of the finger actuation unit 210, and the friction coefficient of the friction module 240 is greater than the friction coefficient of the finger outer sleeve 220.

[0085] Specifically, the finger sheath 220 is made of rubber, the finger actuation unit 210 is made of soft rubber, and the surface roughness of the surface of the friction module 240 on the side away from the finger actuation unit (i.e., the bottom surface of the finger actuation unit 210) is greater than the surface roughness of the bottom surface of the finger actuation unit 210. Thus, after the friction module 240 extends out of the finger bending air cavity 213, it can grasp an object, thereby realizing the friction force adjustment between the soft finger mechanism 200 and the object. Further, the friction module 240 can be made of different materials such as plastic, silica gel, sponge, rubber, etc., and different surface textures such as stripes, dot matrices, meshes, etc. can be selected, so as to realize various roughness changes and meet the application requirements of the soft hand in various scenarios.

[0086] It should be noted that the hardness of the finger sleeve 220 is greater than that of the finger braking unit 210. Thus, when no gas is filled in the finger actuation unit 210, the finger actuation unit 210 is kept straight and stable through the finger sheath 220, preventing the problems of sagging and swaying that may occur to the finger braking unit 210 due to its softness. And the relatively hard finger sleeve 220 can increase the grasping force after bending to a certain extent, that is, the grasping performance of the bottom surface of the relatively hard finger sleeve 220 in contact with the object (i.e., when grasping the object) is better than that of the relatively soft finger actuation unit 210 directly in contact with the object.

[0087] In this embodiment, as Figures 7 to 10 shown, the soft thumb mechanism 300 includes:

[0088] A thumb actuation unit 310, provided with a thumb bending air cavity 312;

[0089] A thumb sheath 320, which is attached to the outer wall of the thumb actuation unit 310;

[0090] A rotation module 330, provided with a rotation bending air cavity 331;

[0091] A visual and tactile sensor 360, which is arranged on the thumb sheath 320 and is used for texture perception of the surface of the target;

[0092] Wherein, the thumb actuation unit 310 is connected to the thumb rotation module 330, and both the thumb bending air cavity 312 and the rotation bending air cavity 331 can be inflated and expanded to enable the soft thumb mechanism to perform corresponding bending, and the rotation module 330 is rotatably connected to the palm 100.

[0093] As Figure 7 or Figure 10 shown, the soft thumb mechanism 300 further includes:

[0094] A rotation sheath 340, which is attached to the outer wall of the rotation module 330;

[0095] The connecting piece 350 is provided with a first connecting groove and a second connecting groove (not marked in the figure);

[0096] Wherein, the thumb actuating unit 310 is connected to the connecting piece 350 through the first connecting groove, and the rotating module 330 is connected to the connecting piece 350 through the second connecting groove, and the first connecting groove and the second connecting groove are arranged adjacent to each other.

[0097] Specifically, the thumb outer sleeve 320 is nested outside the thumb actuating unit 310, the rotating outer sleeve 340 is nested outside the rotating module 330, and the angle between the first groove (top) and the second groove (right side) is Figure 7 shown as 90 degrees, and the visual tactile sensor 360 is connected to the end of the thumb outer sleeve 320 by screws; as Figure 10 shown, there are two thumb bending air cavities 312, and there is one rotating bending air cavity 331, that is, the rotating bending air cavity 331 of the rotating module 330 is bent relative to the palm 100 to realize rotation, and the two thumb bending air cavities 312 of the thumb actuating unit 310 are used to realize the bending of the two joints on the soft thumb mechanism 300. Further, multiple air pipes of the inflation device are respectively communicated with the rotating bending air cavity 331 and the two thumb bending air cavities 312 to achieve the purpose of inflation and bending or deflation and straightening.

[0098] It should be noted that the materials and functions of the soft thumb mechanism 300 and the soft finger mechanism 200 are similar, that is, the hardness of the thumb outer sleeve (such as rubber) is greater than that of the thumb actuating unit (such as soft rubber), and the hardness of the rotating outer sleeve (such as rubber) is greater than that of the rotating module (such as soft rubber), which will not be elaborated here.

[0099] It should be noted that the visual tactile sensor 360 is essentially a tactile sensor, but it uses the method of photography (vision) to achieve tactile perception. Specifically, such as the DIGIT visual tactile sensor, Digit uses an RGB LED module and a camera module. Since the finger will affect the deformation under different pressures, it will also directly affect the change in the color captured by the camera. By this change, the touch is judged. Placing Digit at the fingertip, it can easily recognize actions such as grasping and pinching.

[0100] In this embodiment, as Figure 13 or Figure 14 shown, the variable friction soft hand further includes:

[0101] A base 410;

[0102] A soft wrist 420, connected to the base 410;

[0103] Among them, the inflation device is connected to the soft wrist 420, the palm 100 is connected to the soft wrist 420, and a plurality of adjustment air chambers 421 are provided inside the soft wrist 420. The adjustment air chambers 421 can be inflated to cause the palm, the soft finger mechanism, and the soft thumb mechanism to bend accordingly.

[0104] Specifically, the soft wrist 420 is also made of a bendable material, such as rubber or silicone. The number of adjustment air chambers 421 is 4, as Figure 14 shown, but not limited thereto, and can also be set to 5, 6. The inflation device uses a proportional valve to connect a plurality of air pipes to a plurality of adjustment air chambers 421 respectively, so as to realize the bending of the soft wrist 420 by adjusting the air pressure difference between different adjustment air chambers 421.

[0105] As Figure 13 and 14 shown, the soft wrist is provided with communication holes corresponding to the adjustment air chambers 421 respectively, and the base 410 is also provided with through holes coaxial with the communication holes, so as to facilitate the connection of the air pipes to the adjustment air chambers.

[0106] As Figures 11 to 13 shown, the palm 100 is provided with an air pipe fixing groove 101, so that a plurality of air pipes are fixed through the air pipe fixing groove 101. The palm 100 is connected to the soft wrist 420 through a connecting member 420, and the air pipes fixed on the air pipe fixing groove 101 pass through the central strip-shaped hole of the connecting member.

[0107] In this embodiment, as Figure 2 、 Figure 6 and Figure 7 shown, the number of the finger bending air chambers 213 and the airbag chambers 214 is three each. The finger actuating unit 210 and the finger outer sleeve 220 are respectively provided with three corresponding first air holes 211 and second air holes 221. The finger bending air chambers 213 are communicated with the outside through the first air holes 211 and the second air holes 221. The finger actuating unit 210 and the finger outer sleeve 220 are respectively provided with three corresponding third air holes 212 and fourth air holes 222. The airbag chambers 214 are communicated with the outside through the third air holes 212 and the fourth air holes 222.

[0108] Specifically, the first air hole 211 on the correspondingly arranged finger actuating unit is coaxial with the second air hole 221 on the finger outer sleeve, and the third air hole 212 on the correspondingly arranged finger actuating unit is coaxial with the fourth air hole 222 on the finger outer sleeve. That is to say, after the air pump is connected to the proportional valve, the proportional valve is connected to the finger bending air cavity 213 through multiple air pipes passing through the second air hole 221 and the first air hole 211 respectively (to realize the bending of the soft finger mechanism), and is connected to the airbag cavity 214 through the fourth air hole 222 and the third air hole 212 (to realize the change in the friction force of the soft finger mechanism); further, on the side of the airbag block 230 away from the opening of the airbag cavity 214 (i.e., the top of the airbag block, which is also Figure 2 the front side shown) there is an inflation hole (not marked in the figure), and the inflation hole is opposite to the third air hole 212, so as to facilitate the gas entering the airbag cavity to expand the airbag block 230 through the inflation hole, thereby increasing the friction force.

[0109] In this embodiment, as Figure 14 shown, the number of the soft finger mechanisms is set to four, and the four soft finger mechanisms 200 are respectively connected to the first installation position 110, the second installation position 120, the third installation position 130 and the fourth installation position 140 of the palm, and the soft thumb mechanism 200 is connected to the fifth installation position 150 of the palm 100.

[0110] Control principle of the soft hand: When each component is placed flat, the base 410 supports the body. The soft hand realizes the bending and expansion of the finger actuating unit 210, the thumb actuating unit 310, the rotation module 330, the soft wrist 420, and the airbag block 230 by controlling the air pressure in the air cavity. Through the bending of the finger actuating unit 210, the thumb actuating unit 310, and the rotation module 330, it can imitate the bending of the human finger joints to realize different gestures and grasping postures. By adjusting the expansion of the airbag block 230, the change in the surface friction coefficient of the soft finger is realized. By adjusting the air pressure difference between the air cavities of the soft wrist 420, the overall swing and bending of the soft hand are realized.

[0111] In the present invention, through the bending of the thumb actuating unit 310 and the rotation module 330, the visual and tactile sensor 360 contacts and presses the object to realize the perception of the surface texture shape of the object; through the expansion and bending of each air cavity of the soft finger and the soft thumb, the grasping action of the object is realized, and through the expansion of the airbag block 230, the friction module with a larger friction coefficient contacts the object and applies pressure to realize a more stable grasp.

[0112] In another embodiment, the palm simulates the human palm, so that it can also be bent, further improving the application range of the variable friction soft hand.

[0113] Based on the above embodiments, a grasping method for a variable friction soft hand is applied to the variable friction soft hand capable of perceiving texture shape asFigure 15 As shown, the method includes:

[0114] Step S100: Control the soft thumb mechanism to perform texture perception on the surface of the target to obtain the surface shape information of the target;

[0115] Step S200: Adjust the soft finger mechanism according to the surface shape information of the target to determine the friction force information corresponding to the soft finger mechanism;

[0116] Step S300: Control the soft thumb mechanism and the soft finger mechanism to grasp the target according to the friction force information corresponding to the soft finger mechanism and the surface shape information of the target.

[0117] In one implementation, the variable friction soft hand further includes:

[0118] An inflation device, respectively connected to the soft finger mechanism 200 and the soft thumb mechanism 300;

[0119] The surface shape information of the target includes the surface roughness information of the target and the shape contour information of the target;

[0120] The specific content of step S200 includes:

[0121] According to the surface roughness information of the target, control the inflation device to adjust the soft finger mechanism to determine the friction force information corresponding to the soft finger mechanism.

[0122] The grasping method of the variable friction soft hand provided by the present invention is applied to the above-mentioned variable friction soft hand that can sense texture and shape, so it has all the beneficial effects of the above-mentioned variable friction soft hand that can sense texture and shape, and the principle of grasping the target is also the same, which will not be elaborated here.

[0123] In summary, the present invention provides a variable friction soft hand that can sense texture and shape and its grasping method. Among them, the variable friction soft hand includes: a palm; a soft thumb mechanism, connected to the palm, and the soft thumb mechanism can bend relative to the palm; a soft finger mechanism, connected to the palm, and the soft finger mechanism can bend relative to the palm. The present invention bends the soft thumb mechanism relative to the palm, so that the soft thumb mechanism contacts the target for texture perception, and then obtains the surface shape information of the target. Moreover, the soft finger mechanism can adjust its own friction force, so that the soft finger mechanism bends relative to the palm, so that the target is grasped by the soft finger mechanism and the soft thumb mechanism, or the target is grasped by the soft finger mechanism and the palm, improving the perception performance and adaptive performance of the target, thereby expanding the applicable range, and achieving the effects of protecting the target and improving the grasping stability of the target.

[0124] It should be understood that the application of the present invention is not limited to the above examples. For those of ordinary skill in the art, improvements or modifications can be made according to the above description, and all such improvements and modifications should fall within the protection scope of the appended claims of the present invention.

Claims

1. A variable-friction soft hand capable of perceiving texture shape, characterized in that, It includes: Palm; Soft thumb mechanism, connected to the palm, the soft thumb mechanism can bend relative to the palm, and is used to sense the texture of the surface of the target to obtain the surface shape information of the target; Soft finger mechanism, connected to the palm, the soft finger mechanism can bend relative to the palm, and is used to adjust the soft finger mechanism according to the surface shape information of the target to determine the corresponding friction force information of the soft finger mechanism; The soft finger mechanism and the soft thumb mechanism cooperate with each other and can be used to grasp the target according to the corresponding friction force information of the soft finger mechanism and the surface shape information of the target; The soft finger mechanism includes: Finger actuation unit, provided with a plurality of finger bending air chambers and a plurality of airbag chambers; Finger outer sleeve, which is arranged in a fitting manner on the outer wall of the finger actuation unit; A plurality of airbag blocks, connected to the inner wall of the airbag chamber; A plurality of friction modules, connected to the airbag blocks, and used to grasp the target; Among them, the plurality of airbag chambers, the plurality of airbag blocks, and the plurality of friction modules correspond one by one, the finger bending air chamber and the airbag chamber are correspondingly arranged, the finger bending air chamber can be inflated to make the finger actuation unit bend accordingly, the airbag block can be inflated, and the friction module can be slidably connected to the finger outer sleeve to determine the corresponding friction force information of the soft finger mechanism.

2. The variable-friction soft hand capable of perceiving texture shape according to claim 1, characterized in that, The variable friction soft hand further includes: Inflation device, respectively connected to the soft finger mechanism and the soft thumb mechanism, and used to control the respective bending degrees of the soft finger mechanism and the soft thumb mechanism, and control the corresponding friction force information of the soft finger mechanism.

3. The variable friction soft hand capable of perceiving texture shape according to claim 1, characterized in that The soft thumb mechanism includes: Thumb actuation unit, provided with a thumb bending air chamber; Thumb outer sleeve, which is arranged in a fitting manner on the outer wall of the thumb actuation unit; Rotation module, provided with a rotation bending air chamber; Visual tactile sensor, arranged on the thumb outer sleeve, and used to sense the texture of the surface of the target; Among them, the thumb actuation unit is connected to the rotation module, the thumb bending air chamber and the rotation bending air chamber can both be inflated to make the soft thumb mechanism bend accordingly, and the rotation module is rotatably connected to the palm.

4. The variable-friction soft hand capable of perceiving texture shape according to claim 1, wherein The strength of the finger outer sleeve is greater than the strength of the finger actuation unit, and the friction coefficient of the friction module is greater than the friction coefficient of the finger outer sleeve.

5. The variable-friction soft hand capable of perceiving texture shape according to claim 2, characterized in that, The variable friction soft hand further includes: Base; Soft wrist, connected to the base; Among them, the inflation device is connected to the soft wrist, the palm is connected to the soft wrist, and a plurality of adjustment air chambers are arranged in the soft wrist, and the adjustment air chambers can be inflated to make the palm, the soft finger mechanism and the soft thumb mechanism bend accordingly.

6. The variable-friction soft hand capable of perceiving texture shape according to claim 3, characterized in that, The number of the finger bending air chambers and the airbag chambers is three. The finger actuating unit and the finger outer sleeve are respectively provided with three corresponding first air holes and second air holes. The finger bending air chambers are communicated with the outside through the first air holes and the second air holes. The finger actuating unit and the finger outer sleeve are respectively provided with three corresponding third air holes and fourth air holes. The airbag chambers are communicated with the outside through the third air holes and the fourth air holes.

7. The variable friction soft hand capable of perceiving texture shape according to claim 1, wherein The number of the soft finger mechanisms is set to four. The four soft finger mechanisms are respectively connected to the first installation position, the second installation position, the third installation position and the fourth installation position of the palm. The soft thumb mechanism is connected to the fifth installation position of the palm.

8. A grasping method for a variable-friction soft hand capable of perceiving texture shapes according to any one of claims 1 to 7, characterized in that, The method includes: Controlling the soft thumb mechanism to perform texture perception on the surface of the target to obtain the surface shape information of the target; Adjusting the soft finger mechanisms according to the surface shape information of the target to determine the corresponding friction force information of the soft finger mechanisms; Controlling the soft thumb mechanism and the soft finger mechanisms to grasp the target according to the corresponding friction force information of the soft finger mechanisms and the surface shape information of the target.

9. The grasping method of the variable-friction soft hand capable of perceiving texture shape according to claim 8, characterized in that The variable friction soft hand further includes: An inflation device, which is respectively connected to the soft finger mechanisms and the soft thumb mechanism; The surface shape information of the target includes the surface roughness information and the shape contour information of the target; The adjusting the soft finger mechanisms according to the surface shape information of the target to determine the corresponding friction force information of the soft finger mechanisms includes: Controlling the inflation device to adjust the soft finger mechanisms according to the surface roughness information of the target to determine the corresponding friction force information of the soft finger mechanisms.

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