Rigidity-variable soft finger, rigidity-variable soft gripper and manipulator

Abstract

The invention discloses a rigidity-variable soft finger, a rigidity-variable soft gripper and a manipulator, the rigidity-variable soft finger comprises a soft finger main body and a mounting structure, a clamping surface is arranged outside the soft finger main body, a soft chamber and a vacuum chamber are arranged in the soft finger main body, the soft chamber and the vacuum chamber both extend along the length direction of the soft finger, and the mounting structure is arranged in the soft finger main body. The soft cavity is separated from the vacuum cavity, and the vacuum cavity is located between the soft cavity and the clamping face; the installation structure is installed at one end of the soft finger body and provided with a hard elastic piece, an air inlet hole and an air exhaust hole, the air inlet hole is communicated with the soft cavity, the air exhaust hole is communicated with the vacuum cavity, and the hard elastic piece is located in the vacuum cavity and extends in the length direction of the vacuum cavity. According to the technical scheme, the rigidity-variable soft finger can be suitable for complex working environments and grabbed objects.

Description

Technical Field

[0001] The present invention relates to the field of robot technology, and in particular to a soft finger with variable stiffness, a soft gripper with variable stiffness and a manipulator. Background Art

[0002] With the continuous development of the robotics industry, humans are increasingly using robotics technology in production and life. In recent years, with the development of materials, rapid prototyping and other technologies, soft hands made of soft materials have begun to attract attention from all walks of life. Soft grippers are based on human hands and use the deformable and bendable characteristics of soft materials to improve rigid manipulators. Soft grippers have the advantages of gentle grasping and flexible postures. They have greater advantages than rigid hands in grasping fragile objects or in complex environments such as human-computer interaction. Their appearance provides an idea and direction for solving problems such as poor environmental adaptability and poor flexibility of rigid hands.

[0003] As the application areas of robots continue to expand, the working environment and the objects they act on become more complex, which places higher requirements on the performance of grippers.

[0004] Traditional rigid grippers are usually designed to grasp objects of specific shapes. They lack flexibility and have poor adaptability, making it difficult to effectively handle irregular or diverse objects. In addition, when grasping fragile or fragile objects, the rigid structure is prone to damage the objects and cannot provide the required gentle grasping force. The emergence of soft grippers breaks the limitations of traditional rigid grippers' lack of flexibility and poor adaptability, and broadens the application scope of robot grasping.

[0005] However, soft grippers are usually made of flexible materials and have limited gripping force due to insufficient stiffness, making them inapplicable to high-speed pick-and-place tasks for fragile objects such as fruits. They cannot meet the requirements of modern automation applications for flexibility, stability, and safety. Summary of the invention

[0006] The main purpose of the present invention is to provide a soft finger with variable stiffness, which is intended to be applicable to complex working environments and grasping objects.

[0007] To achieve the above object, the soft finger with variable stiffness proposed by the present invention comprises:

[0008] A soft finger body, wherein the soft finger body has a clamping surface on the outside, and a soft body chamber and a vacuum chamber are arranged inside the soft finger body, wherein the soft body chamber and the vacuum chamber both extend along the length direction of the soft finger, the soft body chamber and the vacuum chamber are separated from each other, and the vacuum chamber is located between the soft body chamber and the clamping surface; and

[0009] The mounting structure is mounted on one end of the soft finger body, and the mounting structure is provided with a hard spring sheet, an air inlet hole and an air extraction hole. The air inlet hole is connected to the soft body chamber, and the air extraction hole is connected to the vacuum chamber. The hard spring sheet is located in the vacuum chamber and extends along the length direction of the vacuum chamber.

[0010] Optionally, the mounting structure is provided with a plurality of the hard spring sheets, and the plurality of the hard spring sheets are all located in the vacuum chamber and are stacked in a direction from the soft chamber to the clamping surface.

[0011] Optionally, the mounting structure includes a fixing seat and a hard part, the fixing seat is provided with the air inlet hole and the air extraction hole, and is mounted on one end of the soft finger body, the hard part includes a mounting part and a plurality of the hard spring sheets, one end of the plurality of the hard spring sheets is integrally formed with the mounting part, two adjacent hard spring sheets are spaced apart, and the mounting part is mounted on the fixing seat;

[0012] The variable stiffness soft finger further comprises a first sealing gasket, which is arranged between the fixing seat and the soft finger body.

[0013] Optionally, the soft finger body includes an integrally formed soft finger portion and a connecting portion, the soft finger portion has the clamping surface on the outside, the soft finger portion is provided with the soft body chamber and the vacuum chamber inside, the soft body chamber and the vacuum chamber both form a cavity opening at one end of the soft finger portion, the connecting portion is provided with a through hole corresponding to each cavity opening, the outer peripheral surface of the connecting portion is provided with an external thread, and the fixing seat is provided with a screw hole matching the external thread so as to be screwed to the connecting portion;

[0014] The variable stiffness soft finger also includes a second sealing gasket, which is arranged between the via hole and the air inlet hole.

[0015] Optionally, the fixing seat comprises a fixing body and a fixing sleeve, the fixing body is provided with the air inlet hole and the air extraction hole, a limiting block is convexly provided on the outer circumferential surface of the fixing body, the hard member is mounted on the fixing body, the fixing sleeve is sleeved on the outer side of the fixing body, the inner side wall of the fixing sleeve is provided with a limiting groove, the limiting groove is annular and extends along the circumferential direction of the fixing sleeve, the limiting block extends into the limiting groove, the inner side wall of the fixing sleeve is further provided with an internal thread, and the screw hole is formed between the inner side wall of the fixing sleeve and the bottom surface of the fixing body;

[0016] The variable stiffness soft finger also includes a third sealing gasket, which is arranged between the bottom surface of the screw hole and the connecting part.

[0017] Optionally, an end surface of the soft finger body away from the air inlet hole and the air extraction hole is arranged in an arc shape between the clamping surface.

[0018] Optionally, the soft finger further comprises a hard plate, wherein the hard plate is arranged on a side opposite to the clamping surface and located at an end away from the air inlet and the air extraction hole.

[0019] Optionally, the soft chamber includes a plurality of interconnected deformation cavities, each of the deformation cavities is raised on the outer side of the soft finger body to form a convex portion, and two adjacent convex portions are spaced apart from each other. The soft finger also includes a plurality of hard structures, one hard structure is arranged corresponding to one convex portion, and each of the hard structures is connected between the two sides of the deformation of the convex portion and extends along the circumference of the convex portion.

[0020] The present invention also proposes a soft gripper with variable stiffness, which comprises a mounting frame and a plurality of soft fingers with variable stiffness as described above, wherein the plurality of soft fingers with variable stiffness are all mounted on the mounting frame and are distributed at intervals along the circumference of the mounting frame, and the mounting frame is used to be installed on a manipulator.

[0021] The present invention further provides a manipulator, comprising a manipulator arm and the variable stiffness soft gripper as described above, wherein the manipulator arm is connected to a mounting frame of the variable stiffness soft gripper.

[0022] The technical solution of the present invention is to set a soft body chamber and a vacuum chamber in the soft finger body, extend the soft body chamber and the vacuum chamber along the length direction of the soft finger, and separate them from each other, and the vacuum chamber is located between the soft body chamber and the clamping surface, install the mounting structure at one end of the soft finger body, and set a hard spring sheet, an air inlet hole and an air extraction hole, the air inlet hole is connected with the soft body chamber, the air extraction hole is connected with the vacuum chamber, the hard spring sheet is located in the vacuum chamber, and extends along the length direction of the vacuum chamber. The air pump inputs gas into the soft body chamber through the air inlet hole, and as the gas enters the soft body chamber, the soft body chamber expands, causing bending in the direction of the clamping surface and axial elongation. When the inflation is completed, the vacuum pump draws out the gas in the vacuum chamber through the exhaust port, so that the cavity wall of the vacuum chamber is deformed in the direction of the hard spring piece and rubs against the outer side of the hard spring piece. As the gas is continuously drawn out of the vacuum chamber, the friction between the cavity wall of the vacuum chamber and the outer side of the hard spring piece continues to increase, thereby increasing the overall stiffness of the soft finger body, so that the soft finger body has both the flexibility of a soft finger and the gripping power of a rigid finger, so that it can be applied to different fields, complex working environments and grasping objects to meet the different usage needs of users. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0024] Figure 1 It is a structural schematic diagram of an embodiment of a soft finger with variable stiffness according to the present invention;

[0025] Figure 2 for Figure 1 Side view of a soft finger with variable stiffness;

[0026] Figure 3 for Figure 1 Cross-sectional view of a soft finger with variable stiffness;

[0027] Figure 4 for Figure 1 Exploded view of a soft finger with variable stiffness;

[0028] Figure 5 for Figure 4 Structural schematic diagram of the installation structure;

[0029] Figure 6 for Figure 4 A cross-sectional view of the middle soft finger body;

[0030] Figure 7 for Figure 6 Schematic diagram of the structure of the medium-hard structure;

[0031] Figure 8 It is a schematic structural diagram of an embodiment of a soft gripper with variable stiffness according to the present invention.

[0032] Description of Figure Numbers:

[0033] 100, soft finger; 110, mounting frame; 10, soft finger body; 11, soft finger part; 111, soft body chamber; 1111, deformation chamber; 112, vacuum chamber; 113, clamping surface; 12, connecting part; 121, through hole; 13, convex part; 20, mounting structure; 21, fixing seat; 211, fixing body; 2111, air inlet hole; 2112, air extraction hole; 2113, limiting block; 212, fixing sleeve; 2121, limiting groove; 22, hard part; 221, mounting part; 222, hard spring piece; 30, hard structure; 31, arc section; 32, connecting section; 40, hard plate; 50, first sealing gasket; 60, second sealing gasket; 70, third sealing gasket

[0034] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0037] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text is to include three parallel solutions. Taking "A and / or B" as an example, it includes solution A, or solution B, or a solution that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0038] The invention provides a soft finger with variable stiffness, which is used for a soft gripper with variable stiffness.

[0039] In the embodiment of the present invention, Figures 1 to 7 As shown, the variable stiffness soft finger 100 includes a soft finger body 10 and a mounting structure 20 .

[0040] Specifically, the soft finger body 10 has a clamping surface 113 on the outside, and the clamping surface 113 is the surface that contacts the surface of the object when grasping the object. The soft finger body 10 is provided with a soft chamber 111 and a vacuum chamber 112. The soft chamber 111 and the vacuum chamber 112 both extend along the length direction of the soft finger body 10. The soft chamber 111 and the vacuum chamber 112 are separated from each other, and the vacuum chamber 112 is located between the soft chamber 111 and the clamping surface 113. Among them, the soft finger body 10 is made of a flexible material so that it can be deformed in the state of inflation and exhaust. Exemplarily, the flexible material can be but not limited to: silicone, polyurethane or ABS plastic, Agilus30, etc. It can be set according to actual conditions, and this application does not make specific restrictions on this.

[0041] The mounting structure 20 is mounted on one end of the soft finger body 10. The mounting structure 20 is provided with a hard spring sheet 222, an air inlet 2111 and an air extraction hole 2112. The air inlet 2111 is connected to the soft body chamber 111. The air pump is connected to the soft body chamber 111 through the air inlet 2111.

[0042] The walls of the air inlet 2111 and the air extraction hole 2112 are both provided with internal threads to form M5×0.8 threaded holes, which are convenient for connection with common air source equipment.

[0043] In this embodiment, the soft body chamber 111 includes a plurality of interconnected deformation chambers 1111, each deformation chamber 1111 is raised on the outside of the soft finger body 10 to form a convex portion 13, and two adjacent convex portions 13 are spaced apart from each other, so that the soft finger body 10 is arranged in a corrugated structure. In this way, when the air pump inputs gas into the soft body chamber 111 through the air inlet 2111, the wall of each deformation chamber 1111 will expand along the contour of its corrugation. Since the corrugation is a geometric shape, the expansion degree of the gas in different areas is different. This uneven expansion causes the soft finger body 10 to bend and deform in a specific direction. In other words, the local pressure difference caused by the corrugated structure causes the soft finger body 10 to bend and deform.

[0044] Specifically, the number of deformation cavities 1111 is nine, that is, the nine deformation cavities 1111 are interconnected to form a soft body chamber 111. Setting the number of deformation cavities 1111 to nine can make the soft finger body 10 have better flexibility and operability, and can also make the soft finger body 10 have a certain load-bearing capacity while maintaining lightweight. Of course, in other embodiments, the number of deformation cavities 1111 can be ten, eleven, twelve, etc., which can be set according to actual conditions, and this application does not make specific restrictions on this.

[0045] The air extraction hole 2112 is connected to the vacuum chamber 112, and the hard spring sheet 222 is located in the vacuum chamber 112 and extends along the length direction of the vacuum chamber 112. The vacuum pump is connected to the vacuum chamber 112 through the air extraction hole 2112, and the gas in the vacuum chamber 112 is extracted by the vacuum pump, so that the cavity wall of the vacuum chamber 112 is deformed in the direction of the hard spring sheet 222, and rubs against the outer side surface of the hard spring sheet 222. As the gas is continuously extracted from the vacuum chamber 112, the friction between the cavity wall of the vacuum chamber 112 and the outer side surface of the hard spring sheet 222 is continuously increased, thereby increasing the overall rigidity of the soft finger body 10, so that the soft finger body 10 has both the flexibility of the soft finger 100 and the grip of the rigid finger.

[0046] In addition, by controlling the gas input amount in the soft body chamber 111, the bending angle of the soft finger body 10 can be controlled, and by controlling the gas extraction amount in the vacuum chamber 112, the rigidity of the soft finger body 10 can be controlled. In this way, the gas input amount in the soft body chamber 111 and the gas extraction amount in the vacuum chamber 112 can be controlled according to the characteristics of the object to be grasped, thereby achieving more flexible grasping.

[0047] The technical solution of the present invention is to set a soft chamber 111 and a vacuum chamber 112 in the soft finger body 10, extend the soft chamber 111 and the vacuum chamber 112 along the length direction of the soft finger and separate them from each other, and the vacuum chamber 112 is located between the soft chamber 111 and the clamping surface 113, and install the mounting structure 20 at one end of the soft finger body 10, and set a hard spring piece 222, an air inlet hole 2111 and an air extraction hole 2112, the air inlet hole 2111 is connected with the soft chamber 111, and the air extraction hole 2112 is connected with the vacuum chamber 112, and the hard spring piece 222 is located in the vacuum chamber 112 and extends along the length direction of the vacuum chamber 112. In this way, when in use, the air pump inputs gas into the soft chamber 111 through the air inlet 2111. As the gas enters the soft chamber 111, the soft chamber 111 expands, causing deformation such as bending in the direction of the clamping surface 113 and axial elongation. When the inflation is completed, the vacuum pump extracts the gas in the vacuum chamber 112 through the air extraction hole 2112, so that the cavity wall of the vacuum chamber 112 deforms in the direction of the hard spring sheet 222 and rubs against the outer side of the hard spring sheet 222. As the gas is continuously extracted from the vacuum chamber 112, the friction between the cavity wall of the vacuum chamber 112 and the outer side of the hard spring sheet 222 increases continuously, thereby increasing the overall rigidity of the soft finger body 10, so that the soft finger body 10 has both the flexibility of the soft finger 100 and the gripping force of the rigid finger, so that it can be applied to different fields, complex working environments and grasping objects to meet the different usage requirements of users.

[0048] In some embodiments, the mounting structure 20 is provided with a plurality of hard elastic sheets 222 . The plurality of hard elastic sheets 222 are all located in the vacuum chamber 112 and are stacked in a direction from the soft chamber 111 to the clamping surface 113 .

[0049] Specifically, the number of hard spring pieces 222 is at least two, and two adjacent hard spring pieces 222 are spaced apart from each other. When the vacuum pump draws out the gas in the vacuum chamber 112, the pressure inside the vacuum chamber 112 decreases, and the squeezing force between the hard spring pieces 222 increases. As the gas is continuously drawn out from the vacuum chamber 112, the friction force between the outer sides of the multiple hard spring pieces 222 increases continuously, so that the multiple hard spring pieces 222 are attached to each other as a whole, thereby increasing the rigidity of the clamping surface 113, which is beneficial to improving the rigidity of the soft finger body 10.

[0050] It is worth noting that by controlling the amount of gas extracted from the vacuum chamber 112, the friction between the multiple hard springs 222 can be controlled, thereby controlling the rigidity of the soft finger body 10. Specifically, when the vacuum pump is controlled to extract only a small amount of gas from the vacuum chamber 112, the friction between the multiple hard springs 222 is small, and the friction between the vacuum chamber wall 112 and the surface of the hard spring 222 is also small, so the rigidity of the soft finger body 10 is low. When the vacuum pump is controlled to completely or mostly extract the gas from the vacuum chamber 112, the friction between the multiple hard springs 222 is large, and the friction between the vacuum chamber wall 112 and the surface of the hard spring 222 is also large, so the rigidity of the soft finger body 10 is high. In this way, the amount of gas extracted from the vacuum chamber 112 can be controlled according to the characteristics of the object to be grasped to adjust the rigidity of the soft finger body 10, so as to achieve variable rigidity of the soft finger body 10. For example, the number of the hard spring pieces 222 may be, but is not limited to, two, three, four, five, six, etc. The number may be set according to actual conditions.

[0051] Furthermore, the number of hard spring sheets 222 is six, the thickness of each hard spring sheet 222 is 0.3 mm, and the spacing between two adjacent hard spring sheets 222 is 0.4 mm. Six 0.3 mm thick hard spring sheets 222 are stacked together with a gap of 0.4 mm, so that during the air extraction process, there is a larger contact area and friction between two adjacent hard spring sheets 222, which is beneficial to improve the rigidity of the soft finger body 10 and optimize the gripping effect. Moreover, the number of hard spring sheets 222 is set to six, which can ensure that the soft finger body 10 has a good variable rigidity capability and output capability, and will not increase the control difficulty of the soft finger body 10. Of course, in other embodiments, the mounting structure 20 is only provided with one hard spring sheet 222.

[0052] In some embodiments, the mounting structure 20 includes a fixed seat 21 and a hard part 22. The fixed seat 21 is provided with an air inlet hole 2111 and an air exhaust hole 2112, and is installed at one end of the soft finger body 10. The hard part 22 includes a mounting portion 221 and a plurality of hard spring clips 222. One end of the plurality of hard spring clips 222 is integrally formed with the mounting portion 221. Adjacent two hard spring clips 222 are spaced apart, and the mounting portion 221 is installed on the fixed seat 21.

[0053] Specifically, one end of a plurality of hard elastic sheets 222 is integrally formed with the mounting portion 221, and a nested layer interference structure is formed between two adjacent hard elastic sheets 222. Such an arrangement makes it difficult for two adjacent hard elastic sheets 222 to slip, thereby avoiding the occurrence of structural instability and the difficulty in maintaining rigidity. In addition, if the hard elastic sheet 222 is directly mounted on the fixing seat 21, the hard elastic sheet 222 is easy to fall off the fixing seat 21 when deformed. When the mounting portion 221 is set, the mounting portion 221 itself will not be deformed, so that the mounting portion 221 can be reliably connected to the fixing seat 21. Of course, in other embodiments, one end of the hard elastic sheet 222 is integrally formed with the fixing seat 21. Optionally, a first sealing gasket 50 is provided between the fixing seat 21 and the soft finger body 10. To improve the sealing between the fixing seat 21 and the soft finger body 10 and prevent air leakage.

[0054] In some embodiments, the soft finger body 10 includes an integrally formed soft finger portion 11 and a connecting portion 12, the soft finger portion 11 has a clamping surface 113 on the outside, and a soft chamber 111 and a vacuum chamber 112 are provided inside the soft finger portion 11. The soft chamber 111 and the vacuum chamber 112 both form cavities at one end of the soft finger portion 11, and the connecting portion 12 has a through hole 121 corresponding to each cavity, and the outer peripheral surface of the connecting portion 12 is provided with an external thread, and the fixing seat 21 is provided with a screw hole matching the external thread so as to be screwed to the connecting portion 12.

[0055] Specifically, the air inlet 2111 is connected to the soft chamber 111 through the via 121, and the air extraction hole 2112 is connected to the vacuum chamber 112 through another via 121. The soft finger body 10 and the mounting structure 20 are connected by threads, which is easy to disassemble and has strong connection stability. In this way, when any structure is damaged, it can be directly replaced, which is convenient and quick, and is conducive to reducing maintenance costs. Optionally, a second sealing gasket 60 is provided between the air inlet 2111 and the via 121. To improve the air tightness between the air inlet 2111 and the via 121 and prevent air leakage.

[0056] Furthermore, a rounded corner is provided between the clamping surface 113 and the connecting portion 12. Providing a rounded corner between the clamping surface 113 and the connecting portion 12 can reduce friction with other objects and reduce wear, and the rounded corner structure can provide support for the soft finger body 10, reduce the influence of its own gravity, thereby reducing the initial drooping angle, which is more conducive to grasping objects.

[0057] In some embodiments, the fixed seat 21 includes a fixed body 211 and a fixed sleeve 212, the fixed body 211 is provided with an air inlet hole 2111 and an air exhaust hole 2112, a limit block 2113 is convexly provided on the outer peripheral surface of the fixed body 211, the hard part 22 is installed on the fixed body 211, the fixed sleeve 212 is sleeved on the outside of the fixed body 211, the inner side wall of the fixed sleeve 212 is provided with a limit groove 2121, the limit groove 2121 is annular and extends along the circumference of the fixed sleeve 212, the limit block 2113 extends into the limit groove 2121, the inner side wall of the fixed sleeve 212 is also provided with an internal thread, and a screw hole is formed between the inner side wall of the fixed sleeve 212 and the bottom surface of the fixed body 211.

[0058] Specifically, the limiting block 2113 cooperates with the limiting groove 2121 to drive the fixed body 211 to move through the knob fixing sleeve 212, thereby preventing the hard spring sheet 222 from interfering with the rotational movement of the fixing sleeve 212.

[0059] Specifically, in one embodiment, the stopper 2113 is in a ring shape extending along the circumference of the fixed body 211. In another embodiment, a plurality of stopper blocks 2113 are provided on the outer circumference of the fixed body 211, and the plurality of stopper blocks 2113 are distributed at intervals along the circumference of the fixed body 211. Optionally, a third sealing gasket 70 is provided between the bottom surface of the screw hole and the connecting portion 12 to improve the overall air tightness of the soft finger body 10 and prevent air leakage.

[0060] In some embodiments, the end surface of the soft finger body 10 away from the air inlet hole 2111 and the air extraction hole 2112 is arranged in an arc shape with the clamping surface 113 .

[0061] Specifically, when the soft finger body 10 is grasping an object, when the end surface of the soft finger body 10 away from the air inlet hole 2111 and the air extraction hole 2112 is arranged in an arc shape with the clamping surface 113, the contact area of ​​objects of different shapes can be adaptively increased, that is, it is helpful to increase the contact area between the soft finger body 10 and the object, thereby improving the grasping stability. Of course, in other embodiments, the end surface of the soft finger body 10 away from the air inlet hole 2111 and the air extraction hole 2112 is arranged in a plane.

[0062] In some embodiments, the variable stiffness soft finger 100 further includes a hard plate 40 , which is disposed on a side opposite to the clamping surface 113 and at an end away from the air inlet 2111 and the air extraction hole 2112 .

[0063] Specifically, the hard plate 40 can enhance the strength of the end of the soft finger body 10 away from the air inlet hole 2111 and the air extraction hole 2112, so as to reduce the deformation of the end of the soft finger body 10 away from the air inlet hole 2111 and the air extraction hole 2112 when the inflation pressure is applied, thereby improving the grasping stability. Of course, in other embodiments, the soft finger 100 with variable stiffness is not provided with the hard plate 40.

[0064] Optionally, the length of the hard plate 40 is 13 mm. The 13 mm hard plate 40 allows the soft finger body 10 to have sufficient grip and good flexibility. It is worth noting that the length of the hard plate 40 is not limited to 13 mm, and the specific length can be set according to the length of the soft finger body 10. For example, when the length of the soft finger body 10 is shortened, the length of the hard structure 30 is shortened accordingly. When the length of the soft finger body 10 is increased, the length of the hard structure 30 is increased accordingly. Therefore, no specific limitation is made.

[0065] In some embodiments, the soft finger 100 further includes a plurality of hard structures 30 , one hard structure 30 is disposed corresponding to one convex portion 13 , and each hard structure 30 is connected between two sides of the deformed convex portion 13 and extends along the circumference of the convex portion 13 .

[0066] Specifically, the hard structure 30 is embedded on both sides of the deformed convex portion 13, and the deformation of the deformation cavity 1111 is limited by the hard structure 30 so that the deformation of the deformation cavity 1111 is mainly concentrated in the axial direction, thereby improving the stability of the soft finger body 10 when grasping an object.

[0067] In addition, the hard structure 30 can not only enhance the stability of the soft finger body 10, but also improve the load capacity and durability. The provision of the hard structure 30 can improve the ability of the soft finger body 10 to resist gravity, thereby reducing the initial drooping angle, which is more conducive to grasping objects.

[0068] Furthermore, the deformation cavity 1111 is arranged in an arc shape on the raised convex portion 13 on the outer side of the soft finger body 10, and the hard structure 30 includes an integrally formed arc segment 31 and a connecting segment 32. The arc segment 31 is connected between the two sides formed by the convex portion 13, and the connecting segment 32 is connected between the two ends of the arc segment 31. One side of the connecting segment 32 forms the cavity wall of the soft cavity 111, and the other side forms the cavity wall of the vacuum cavity 112.

[0069] Specifically, the deformation cavity 1111 is arranged in a semicircular shape, that is, the convex part 13 of the deformation cavity 1111 protruding from the outside of the soft finger body 10 is semicircular, the connecting section 32 is connected between the two ends of the arc section 31, so that the hard structure 30 is a semicircular arch structure, the arc section 31 is connected between the two sides of the deformation of the convex part 13, and the outer peripheral surface of the arc section 31 is flush with the outer peripheral surface of the convex part 13, one side of the connecting section 32 forms the cavity wall of the soft body cavity 111, and the other side forms the cavity wall of the vacuum cavity 112. Such an arrangement facilitates the sealing connection with the deformation cavity 1111.

[0070] Optionally, the arc segment 31 is configured to be rounded at the connection with the wall of the deformation cavity 1111. Such a configuration can effectively reduce stress concentration and extend the service life of the soft finger body 10.

[0071] In some embodiments, the thickness of the hard structure 30 is 1 mm. Specifically, the thickness of 1 mm allows the hard structure 30 to provide sufficient strength while retaining a certain degree of flexibility. The thickness of 1 mm can ensure the stability of the soft finger body 10 during the grasping process, which is more conducive to grasping and applying force. At the same time, this thickness will not make the soft finger 100 as a whole too rigid, and maintains sufficient flexibility. It is worth noting that the thickness of the hard structure 30 is not limited to 1 mm, and the specific thickness can be set according to the size of other structures. For example, when the size of other structures is reduced, the thickness of the hard structure 30 is correspondingly reduced, and when other structures are increased, the thickness of the hard structure 30 is correspondingly increased. Therefore, no specific limitation is made.

[0072] In some embodiments, the hard structure 30 is embedded in the soft finger body 10 through 3D printing technology. Specifically, the application of 3D printing technology enables the hard structure 30 to be integrally formed with the soft finger body 10 during the manufacturing process. Through multi-material 3D printing technology, hard materials and flexible materials can be accurately integrated into the soft finger body 10 in one printing process to improve production efficiency and reduce production costs.

[0073] In addition, due to the high precision and customizability of 3D printing technology, the hard structure 30 can be accurately embedded in different positions of the soft finger body 10 according to specific design requirements. Through this technology, the perfect fit between the hard structure 30 and the soft finger body 10 can be ensured, avoiding the structural weaknesses or failure risks that may occur due to improper bonding or assembly in traditional manufacturing methods.

[0074] Optionally, the hard structure 30 can be made of nylon, plastic, carbon fiber, Vero Pure White (white resin) and other materials.

[0075] In some embodiments, the soft finger body 10, the hard structure 30, the hard plate 40, and the mounting structure 20 are all made using UV curing technology and are integrally formed through multi-material 3D printing. Specifically, UV curing technology is a technology that uses ultraviolet radiation to quickly cure liquid photosensitive resin. This process can manufacture the designed structure in an integrated manner in a short period of time, avoiding assembly errors and bonding problems in traditional manufacturing processes. By using multi-material 3D printing technology, the soft finger body 10 can combine multiple materials, such as rigid materials and flexible materials, in a single printing process to achieve a complex structure that has both functionality and durability.

[0076] Regarding the soft finger body 10, the soft cavity 111 made by UV curing technology can realize the seamless integration of the high-precision deformation cavity 1111 and the hard structure 30. This means that the soft finger body 10 and the hard structure 30 can be accurately manufactured in an integrated molding process to ensure a firm connection between the parts, thereby improving the durability and airtightness of the soft finger body 10.

[0077] Regarding the mounting structure 20, the fixing seat 21 and the hard part 22, the multi-material 3D printing technology can print the hard body of the fixing seat 21, the threaded portion, the first sealing gasket 50, the second sealing gasket 60, the third sealing gasket 70 and the hard part 22 in an integrated manner. The high precision of the UV curing technology enables these functional structures to be precisely formed, thereby achieving a perfect match between the mounting structure 20 and the soft finger body 10, ensuring the sealing performance during the input of gas in the soft body chamber 111 and the extraction of gas in the vacuum chamber 112.

[0078] It can be understood that by adopting UV curing technology and multi-material 3D printing technology for integrated molding, the manufacturing process of the variable stiffness soft finger 100 is more efficient, and the precision and coordination between the parts are higher. This manufacturing method not only reduces the complexity of manual assembly and reduces production costs, but also makes the overall structure of the soft finger 100 more reliable and can be used for grasping tasks in complex working environments.

[0079] The present invention also proposes a soft gripper with variable stiffness, which includes a mounting frame 110 and a plurality of soft fingers 100 with variable stiffness. The specific structure of the soft fingers 100 with variable stiffness refers to the above-mentioned embodiment. Since the soft gripper with variable stiffness adopts all the technical solutions of all the above-mentioned embodiments, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.

[0080] Specifically, a plurality of mounting positions are provided on the circumferential side of the mounting frame 110, and the plurality of mounting positions are spaced apart along the circumference of the mounting frame 110. A variable stiffness soft finger 100 is correspondingly mounted at one mounting position, and the mounting frame 110 is used to be mounted on the manipulator. In this way, a variable stiffness soft gripper is formed by mounting a plurality of variable stiffness soft fingers 100 on the mounting frame 110, which can improve the stability of the variable stiffness soft gripper in grasping objects in a high-speed motion state.

[0081] The variable stiffness soft finger 100 can be detachably installed at the installation position. When any variable stiffness soft finger 100 is damaged, it can be removed and replaced, which is beneficial to reduce the use cost.

[0082] The number of the soft fingers 100 with variable stiffness is at least two, and accordingly, the number of the mounting positions is the same as the number of the soft fingers 100 with variable stiffness. Of course, the number of the mounting positions may be more than the number of the soft fingers 100 with variable stiffness, and in this case, the user may selectively install the soft fingers 100 with variable stiffness according to the use requirements.

[0083] Exemplarily, the number of the variable stiffness soft fingers 100 may be, but is not limited to, two, three, four, five, and so on.

[0084] The present invention also provides a manipulator, which includes a manipulator arm and a soft gripper with variable stiffness. The specific structure of the manipulator refers to the above embodiment. Since the manipulator adopts all the technical solutions of all the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here. Specifically, the mounting frame 110 of the soft gripper with variable stiffness is installed on the manipulator arm through screw hole fasteners.

[0085] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A soft finger with variable stiffness, characterized in that: include: A soft finger body, wherein the soft finger body has a clamping surface on the outside, and a soft body chamber and a vacuum chamber are arranged inside the soft finger body, wherein the soft body chamber and the vacuum chamber both extend along the length direction of the soft finger, the soft body chamber and the vacuum chamber are separated from each other, and the vacuum chamber is located between the soft body chamber and the clamping surface; as well as The mounting structure is mounted on one end of the soft finger body, and the mounting structure is provided with a hard spring sheet, an air inlet hole and an air extraction hole. The air inlet hole is connected to the soft body chamber, and the air extraction hole is connected to the vacuum chamber. The hard spring sheet is located in the vacuum chamber and extends along the length direction of the vacuum chamber.

2. The soft finger with variable stiffness as claimed in claim 1, characterized in that: The mounting structure is provided with a plurality of the hard spring sheets, and the plurality of the hard spring sheets are all located in the vacuum chamber and are stacked in a direction from the soft chamber to the clamping surface.

3. The variable stiffness soft finger according to claim 2, characterized in that: The mounting structure includes a fixing seat and a hard part. The fixing seat is provided with the air inlet hole and the air extraction hole and is mounted on one end of the soft finger body. The hard part includes a mounting part and a plurality of the hard spring sheets. One end of the plurality of the hard spring sheets is integrally formed with the mounting part. Two adjacent hard spring sheets are spaced apart. The mounting part is mounted on the fixing seat. The variable stiffness soft finger further comprises a first sealing gasket, which is arranged between the fixing seat and the soft finger body.

4. The soft finger with variable stiffness as claimed in claim 1, characterized in that: The soft finger body comprises an integrally formed soft finger portion and a connecting portion, the soft finger portion has the clamping surface on the outside, the soft finger portion is provided with the soft body chamber and the vacuum chamber, the soft body chamber and the vacuum chamber both form a cavity opening at one end of the soft finger portion, the connecting portion is provided with a through hole corresponding to each cavity opening, the outer peripheral surface of the connecting portion is provided with an external thread, and the fixing seat is provided with a screw hole matched with the external thread so as to be screwed to the connecting portion; The variable stiffness soft finger also includes a second sealing gasket, which is arranged between the via hole and the air inlet hole.

5. The soft finger with variable stiffness as claimed in claim 4, characterized in that: The fixing seat comprises a fixing body and a fixing sleeve, the fixing body is provided with the air inlet hole and the air extraction hole, a stopper is convexly provided on the outer circumferential surface of the fixing body, the hard part is installed on the fixing body, the fixing sleeve is sleeved on the outer side of the fixing body, a stopper groove is provided on the inner side wall of the fixing sleeve, the stopper groove is annularly extending along the circumferential direction of the fixing sleeve, the stopper extends into the stopper groove, the inner side wall of the fixing sleeve is also provided with an internal thread, and the screw hole is formed between the inner side wall of the fixing sleeve and the bottom surface of the fixing body; The variable stiffness soft finger also includes a third sealing gasket, which is arranged between the bottom surface of the screw hole and the connecting part.

6. The soft finger with variable stiffness as claimed in claim 1, characterized in that: The end surface of the soft finger body away from the air inlet hole and the air extraction hole is arranged in an arc shape between the clamping surface.

7. The variable stiffness soft finger according to claim 1, characterized in that: The soft finger also includes a hard plate, which is arranged on a side opposite to the clamping surface and located at an end away from the air inlet and the air extraction hole.

8. The soft finger with variable stiffness as claimed in claim 1, characterized in that: The soft cavity includes a plurality of interconnected deformation cavities, each of which is raised on the outer side of the soft finger body to form a convex portion, and two adjacent convex portions are spaced apart from each other. The soft finger also includes a plurality of hard structures, one of which is arranged corresponding to one of the convex portions, and each of which is connected between the two sides of the deformation of the convex portion and extends along the circumference of the convex portion.

9. A soft gripper with variable stiffness, characterized in that: The variable stiffness soft gripper comprises a mounting frame and a plurality of variable stiffness soft fingers as claimed in any one of claims 1 to 8, wherein the plurality of variable stiffness soft fingers are mounted on the mounting frame and are distributed at intervals along the circumference of the mounting frame, and the mounting frame is used for being installed on a manipulator.

10. A robot, characterized in that: The manipulator comprises a manipulator arm and a variable stiffness soft gripper as claimed in claim 9, wherein the manipulator arm is connected to a mounting frame of the variable stiffness soft gripper.

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