A manipulator with movable fingers

Abstract

The present invention relates to a manipulator with movable fingers, including a palm and fingers connected to the palm. It is characterized in that an annular guide rail is provided on the outer periphery of the palm, the guide rail is fixedly connected to the palm, and the fingers are rotatably connected to the palm and slidably mounted on the guide rail so as to move along the guide rail. By providing a guide rail on the outer periphery of the palm and enabling at least one of the fingers to slide along the guide rail, the manipulator can move the fingers to specific positions according to different objects, change the positional relationship between the fingers, change the envelope range of the fingers, and realize the mode switching of the manipulator from pinching to grasping.

Description

Technical Field

[0001] The present invention relates to the technical field of manipulators, and particularly to a manipulator with movable fingers. Background Art

[0002] In recent years, robot technology has been continuously developing and widely applied in human social production. As the end effector of a robot, the manipulator has also been extensively studied by domestic and foreign experts and scholars. Compared with rigid manipulators, soft manipulators have superior characteristics such as strong adaptability, large flexibility, and high safety. They can assist humans in completing complex and cumbersome tasks, improve human production efficiency, and are favored in many industries, with a broad research background.

[0003] In the application of manipulators, grasping stability is an important issue. To solve this problem, actions such as bending, rotating, and moving the fingers are usually adopted. For example, the Chinese invention patent application "A Soft Manipulator" (Patent Application No.: CN202110254335.6, Publication No.: CN112809720A) discloses a soft manipulator, which includes: a bionic palm with a palm surface, an end surface, and a side surface; a bionic finger mechanism including a first finger unit and a second finger unit connected to the end surface, and a thumb unit connected to the side surface. The first finger unit is longitudinally and spacedly provided with a plurality of first air cavities on the surface facing away from the palm surface, the second finger unit is longitudinally and spacedly provided with a plurality of second air cavities on the surface facing away from the palm surface, and the thumb unit is transversely and spacedly provided with a left air cavity and a right air cavity on the surface facing away from the palm surface; a pneumatic control mechanism including an air pump, a first switching mechanism connected between the air pump and the bionic finger mechanism for independently controlling the pressure supply to each first air cavity, each second air cavity, the left air cavity, and the right air cavity, and a second switching mechanism for independently controlling the pressure relief of each first air cavity, each second air cavity, the left air cavity, and the right air cavity. This patent improves the grasping stability of an object by inflating the finger units to make the finger units bend.

[0004] Another example is the "Bionic Manipulator" (Patent Application No.: CN202023287342.6, Announcement No.: CN 214187229 U) disclosed in a Chinese utility model patent, which includes a palm and fingers. The palm includes a first movable side and a second movable side that are movably connected to each other. A force-applying arm is provided on the palm surface of the first movable side, and convex arc members are respectively provided on the palm surface of the second movable side and the force-applying arm. A connecting rod is provided for the two convex arc members. The connecting rod is provided with two arc-shaped accommodating portions for accommodating the two convex arc members respectively, so that the connecting rod is respectively connected to the force-applying arm and the second movable side. When the force-applying arm pulls the connecting rod towards the first movable side, the arc-shaped accommodating portion of the connecting rod rotates relative to the corresponding convex arc member, causing the connecting rod to move towards the first movable side and driving the second movable side to rotate in a manner that its palm surface approaches the palm surface of the first movable side. This patent improves the grasping stability of an object through the relative movement of different parts of the palm.

[0005] However, for the manipulator of the above patent, the positions of the fingers cannot change relative to the palm, that is, the range of the fingers enclosing the object cannot be changed, so the grasping stability needs to be further improved. Summary of the Invention

[0006] The first technical problem to be solved by the present invention is to provide a manipulator with fingers that can move circumferentially along the palm according to the current situation of the prior art.

[0007] The second technical problem to be solved by the present invention is to provide a manipulator with a compact driving mechanism for driving the circumferential movement of the fingers according to the current situation of the prior art.

[0008] The technical solution adopted by the present invention to solve the above first technical problem is: a manipulator with movable fingers, including a palm and fingers connected to the palm, characterized in that an annular guide rail is provided on the outer periphery of the palm, the guide rail is fixedly connected to the palm, and the fingers are rotatably connected to the palm and slidably mounted on the guide rail, so as to move along the guide rail.

[0009] Preferably, in order to facilitate the connection of the movable fingers to the guide rail and the palm, the fingers that can move along the guide rail are called movable fingers. An installation seat is provided at the finger root of the movable fingers. The installation seat has a chute that can be slidably matched with the guide rail, and a first connecting rod extending to the back of the palm is provided on the installation seat. The first connecting rod is rotatably connected to the palm through a first rotating shaft, and the first rotating shaft extends in a direction perpendicular to the back of the palm.

[0010] The chute can be open at the top, but in this case, the guide rail still needs to be limited to prevent the guide rail from moving upward relative to the installation seat. Therefore, the movable fingers are located outside the guide rail, the notch of the chute faces the palm, and the guide rail is embedded in the chute; an installation column is provided on the installation seat inside the guide rail, and a roller is installed on the installation column. The inner wall surface of the guide rail contacts the outer peripheral surface of the roller. The chute can limit the guide rail in the vertical direction, and the chute and the installation column can prevent the guide rail from generating displacement in the horizontal direction, and the roller can reduce the friction force on the guide rail.

[0011] In order to drive the movable fingers to rotate, a driving mechanism is provided on the back of the palm to drive the first connecting rod to rotate around the first rotating shaft. Each driving mechanism includes

[0012] A driving member fixedly installed on the back of the palm;

[0013] A piston rod, one end of which is installed on the driving member and is drivingly connected to the driving member, and the piston rod can reciprocate along its axial direction;

[0014] The second connecting rod, one end of which is rotatably connected to the other end of the piston rod through a second rotating shaft, the second rotating shaft extending in a direction perpendicular to the back of the palm. The other end of the second connecting rod is mounted on the first connecting rod, and the other end of the second connecting rod can slide along the length direction of the first connecting rod. When the driving member works, it drives the piston rod to move axially, so that the second connecting rod rotates. The second connecting rod can move along the first connecting rod and drive the first connecting rod to rotate.

[0015] The technical solution adopted by the present invention to solve the above second technical problem is as follows: There are three movable fingers arranged at intervals along the circumferential direction of the guide rail, and each movable finger corresponds to a set of driving mechanisms. The three movable fingers are the first finger, the second finger, and the third finger respectively. Among them, the driving mechanisms corresponding to the second finger and the third finger share the same driving member, and the first connecting rods of the first finger and the second finger share a first rotating shaft.

[0016] In order to improve the grasping stability of the manipulator, the palm is also provided with two fixed fingers fixed relative to it. There are three movable fingers arranged at intervals along the circumferential direction of the guide rail. The two fixed fingers are arranged between two adjacent movable fingers, or there is a fixed finger between every two adjacent movable fingers. In this way, the structure of the manipulator is similar to that of a human hand, and the five fingers cooperate together, and the grasping ability of the object is good.

[0017] In order to further improve the grasping stability of the finger to the object, each finger includes a bending structure that can make the finger bend towards the palm side of the palm. In this way, the contact area between the finger and the spherical object can be further increased, and the grasping is more stable.

[0018] The bending structure can be designed as a structure articulated by multiple joints to realize the bending of the finger. In order to enable the finger to bend and not easily damage the object to be grasped, preferably, the bending structure is a deformable flexible member. On the first side wall of the flexible member facing away from the palm side of the palm, a plurality of partition grooves are arranged at intervals along its length direction, so as to divide the flexible member into multiple units. Each unit is hollow inside, and each unit is connected and communicated. An air inlet hole communicating with the unit at the end is opened on the flexible member. By inflating the flexible member, due to the arrangement of the partition grooves, the flexible member will bend and deform under the action of air pressure.

[0019] Since the flexible member is made of a flexible material, it may result in insufficient grasping force. Therefore, preferably, a hinge structure is provided in the flexible member, and the hinge structure extends along the length direction of the flexible member. The hinge structure is disposed close to the second side wall of the flexible member facing the palm of the hand. The hinge structure can be made of a rigid material, such as a plastic part, which not only does not affect the bending of the flexible member but also ensures the overall stiffness of the finger. In this way, each finger has the effect of resisting lateral bending during the grasping process, and during the grasping process, it has a better adhesion force when contacting the object, improving the accuracy and enveloping property of grasping the object.

[0020] In order to enable the finger to have the maximum bending angle, the hinge structure includes a plurality of links sequentially hinged along the length direction of the flexible member. Adjacent two links are connected by a pivot, and the axis of the pivot extends along the width direction of the second side wall. The pivot is correspondingly arranged in a partition groove, so that the hinge structure does not interfere with the bending of the flexible member, enabling the flexible member to bend to the maximum angle and having the largest possible contact area with a spherical object or an irregular object.

[0021] Compared with the prior art, the advantages of the present invention are as follows: 1. The present invention provides a guide rail on the outer periphery of the palm, and at least one of the fingers can slide along the guide rail. In this way, the manipulator can move the fingers to specific positions according to different objects, change the positional relationship between the fingers, change the enveloping range of the fingers, and realize the mode switching of the manipulator from pinching to grasping.

[0022] 2. The three active fingers of the present invention respectively correspond to three sets of driving mechanisms. However, the driving mechanisms corresponding to the second finger and the third finger share the same driving part, and the first link of the first finger and the first link of the second finger share the same first rotating shaft. In this way, the three sets of driving mechanisms have a simple structure, involve fewer components, and are compact. Otherwise, when the area of the palm is fixed, the structure of the driving mechanism is too complex, which is not only inconvenient to be arranged on the palm but also prone to interference between components. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic structural diagram of an embodiment of the present invention (the manipulator is in an initial state);

[0024] Figure 2 is Figure 1 a schematic structural diagram in another direction;

[0025] Figure 3 is Figure 1 a schematic structural diagram of one of the active fingers and its mounting base in

[0026] Figure 4 is Figure 1 a schematic structural diagram of one of the fingers in

[0027] Figure 5 is Figure 4 a sectional view of;

[0028] Figure 6 is Figure 5 a schematic structural view of the hinge structure in;

[0029] Figure 7 is Figure 1 a schematic view of the bent state of one of the fingers in;

[0030] Figure 8 is a schematic structural view of an embodiment of the present invention (the manipulator is in the grasping state);

[0031] Figure 9 is a schematic structural view of an embodiment of the present invention (the manipulator is in the pinching state). Detailed implementation manners

[0032] The present invention will be further described in detail below in conjunction with the embodiments with reference to the accompanying drawings.

[0033] As Figures 1 to 9 shown, the finger - movable manipulator of this preferred embodiment includes a palm 1 and at least two fingers connected to the palm 1. An annular guide rail 2 is provided on the outer periphery of the palm 1. The guide rail 2 and the palm 1 are fixedly connected through a fixing block 10. At least one of the fingers is rotatably connected to the palm 1 and slidably mounted on the guide rail 2, so as to move along the guide rail 2.

[0034] In this embodiment, there are five fingers, three of which can move along the guide rail 2 and are called movable fingers 3. The three movable fingers 3 are arranged at intervals along the circumferential direction of the guide rail 2.

[0035] The other two fingers are fixedly mounted on the palm 1 and are called fixed fingers 4. In this embodiment, the two fixed fingers 4 are located between two adjacent movable fingers 3. Each fixed finger 4 is fixedly mounted on the guide rail 2 through a fixing seat 41. By moving the movable fingers 3, the relative positional relationship between the five fingers is changed, so that the manipulator is in the grasping state as shown in 8 or in the pinching state as shown in Figure 9 shown. Of course, a fixed finger 4 can also be provided between every two adjacent movable fingers 3, but this structure has a worse pinching effect on objects than the arrangement of this embodiment.

[0036] As Figure 1 、 3 shown, the movable fingers 3 are located outside the guide rail 2. An installation seat 31 is provided at the finger root of the movable fingers 3. The installation seat 31 has a chute 32 that can be slidably fitted with the guide rail 2. The opening of the chute 32 faces the palm 1, and a part of the guide rail 2 is embedded in the chute 32.

[0037] The mounting base 31 is provided with mounting posts 33 located inside the guide rail 2. A roller 34 is mounted on the mounting posts 33. The inner wall surface of the guide rail 2 contacts the outer peripheral surface of the roller 34. An embedding groove 341 for partially accommodating the guide rail 2 is formed on the outer peripheral wall of the roller 34. The chute 32 can limit the guide rail 2 in the vertical direction. The chute 32 and the mounting posts 33 can prevent the guide rail 2 from displacing in the horizontal direction. The roller 34 can reduce the friction force between it and the guide rail 2.

[0038] As Figure 2 shown, the mounting base 31 is provided with a first connecting rod 311 extending to the back of the palm 1. The first connecting rod 311 is rotatably connected to the palm 1 through a first rotating shaft 11. The first rotating shaft 11 extends in a direction perpendicular to the back of the palm 1.

[0039] A driving mechanism 6 for driving the first connecting rod 311 to rotate around the first rotating shaft 11 is provided on the back of the palm 1. Each driving mechanism 6 includes a driving member 61, a piston rod 62 and a second connecting rod 63. The driving member 61 is fixedly mounted on the back of the palm 1. One end of the piston rod 62 is mounted on the driving member 61 and is drivingly connected to the driving member 61. The piston rod 62 can reciprocate along its axial direction.

[0040] One end of the second connecting rod 63 is rotatably connected to the other end of the piston rod 62 through a second rotating shaft 631. The second rotating shaft 631 extends in a direction perpendicular to the back of the palm 1. The other end of the second connecting rod 63 is mounted on the first connecting rod 311. A strip-shaped groove 3111 extending along the length direction of the first connecting rod 311 is formed on the first connecting rod 311. And the other end of the second connecting rod 63 is located in the strip-shaped groove 3111 to slide along the length direction of the first connecting rod 311. When the driving member 61 works, it drives the piston rod 62 to axially move, so that the second connecting rod 63 rotates. The second connecting rod 63 can move along the first connecting rod 311 and drive the first connecting rod 311 to rotate.

[0041] Each movable finger 3 corresponds to a set of driving mechanisms 6. The three movable fingers 3 are respectively the first finger, the second finger and the third finger. Among them, the driving mechanisms 6 corresponding to the second finger and the third finger share the same driving member 61. The first connecting rods 311 of the first finger and the second finger share a first rotating shaft 11. This can reduce the components involved in the mechanical hand and make the structure more concise.

[0042] The above five fingers all include a bending structure that can bend the fingers towards the palm side of the palm. This can further increase the contact area between the fingers and the spherical object and make the grasping more stable.

[0043] As Figures 4 to 7As shown, the bending structure is a flexible member 7 that can be deformed. The flexible member 7 can be made of a flexible material, such as a rubber member. Along the length direction of the first side wall 71 of the flexible member 7 facing away from the palm surface of the palm 1, a plurality of partition grooves 72 are provided at intervals, thereby dividing the flexible member 7 into a plurality of units 73. Each unit 73 is internally hollow, and each unit 73 is connected and communicated through a vent hole 74. An air inlet hole 75 communicating with the unit 73 at the end is opened on the flexible member 7. By inflating the flexible member 7, due to the arrangement of the partition grooves 72, after the flexible member 7 expands under the action of air pressure, it will bend and deform, as Figure 7 Shown is a schematic diagram of the bending state of the flexible member 7 under a 40KPa air pressure.

[0044] A hinge structure 8 is provided in the flexible member 7, and the hinge structure 8 extends along the length direction of the flexible member 7. The hinge structure 8 is arranged close to the second side wall 76 of the flexible member 7 facing the palm surface of the palm 1. The hinge structure 8 can be made of a rigid material, such as a plastic member, which not only does not affect the bending of the flexible member 7 but also ensures the overall stiffness of the finger.

[0045] The hinge structure 8 includes a plurality of links 81 sequentially hinged along the length direction of the flexible member 7. Each link 81 includes a substrate 811. Among two adjacent links 81, a groove 8111 is opened on the substrate 811 of one link 81, and a convex block 8112 that can be accommodated in the groove 8111 is opened on the substrate 811 of the other link 81. The pivot 82 passes through the groove 8111 and the convex block 8112 to rotatably connect the two adjacent links 81, and the axis of the pivot 82 extends along the width direction of the second side wall 76. The pivot 82 is arranged corresponding to the partition groove 72. In this way, the hinge structure 8 will not interfere with the bending of the flexible member 7, enabling the flexible member 7 to bend to the maximum angle and having as large a contact area as possible with a spherical object or an irregular object.

[0046] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are 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. Since the embodiments disclosed in the present invention can be arranged in different directions, these terms indicating directions are only for illustration and should not be regarded as limitations. For example, "upper" and "lower" are not necessarily limited to the directions opposite to or consistent with the direction of gravity.

Claims

1. A manipulator with movable fingers, comprising a palm (1) and fingers connected to the palm (1), characterized in that, An annular guide rail (2) is provided on the outer periphery of the palm (1). The guide rail (2) is fixedly connected to the palm (1). The fingers are rotatably connected to the palm (1) and slidably mounted on the guide rail (2) so as to move along the guide rail (2). The above-mentioned fingers are called movable fingers (3). A mounting seat (31) is provided at the root of the movable finger (3). The mounting seat (31) has a chute (32) that can be slidably engaged with the guide rail (2). And a first connecting rod (311) extending to the back of the palm (1) is provided on the mounting seat (31). The first connecting rod (311) is rotatably connected to the palm (1) through a first rotating shaft (11). The first rotating shaft (11) extends in a direction perpendicular to the back of the palm (1). The movable finger (3) is located outside the guide rail (2). The notch of the chute (32) faces the palm (1). The guide rail (2) is embedded in the chute (32). A mounting post (33) is provided on the mounting seat (31) inside the guide rail (2). A roller (34) is mounted on the mounting post (33). The inner wall surface of the guide rail (2) is in contact with the outer peripheral surface of the roller (34). A driving mechanism (6) for drivingly connecting with the first connecting rod (311) to drive the first connecting rod (311) to rotate around the first rotating shaft (11) is provided on the back of the palm (1). Each driving mechanism (6) includes a driving member (61), fixedly mounted on the back of the palm (1); a piston rod (62), one end of which is mounted on the driving member (61) and is drivingly connected to the driving member (61). The piston rod (62) can reciprocate along its axial direction; a second connecting rod (63), one end of which is rotatably connected to the other end of the piston rod (62) through a second rotating shaft (631). The second rotating shaft (631) extends in a direction perpendicular to the back of the palm (1). The other end of the second connecting rod (63) is mounted on the first connecting rod (311). And the other end of the second connecting rod (63) can slide along the length direction of the first connecting rod (311); There are three movable fingers (3) which are arranged at intervals along the circumference of the guide rail (2). Each movable finger (3) corresponds to a set of driving mechanisms (6). The three movable fingers (3) are the first finger, the second finger and the third finger respectively. Among them, the driving mechanisms (6) corresponding to the second finger and the third finger share the same driving member (61). The first connecting rod (311) of the first finger and the first connecting rod (311) of the second finger share a first rotating shaft (11).

2. The manipulator with movable fingers according to claim 1, characterized in that: Two fixed fingers (4) fixed relative to the palm (1) are further provided on the palm (1). There are three movable fingers (3) which are arranged at intervals along the circumference of the guide rail (2). The two fixed fingers (4) are arranged between two adjacent movable fingers (3), or one fixed finger (4) is provided between each adjacent two movable fingers (3).

3. The manipulator with movable fingers according to any one of claims 1 to 2, characterized in that: Each finger includes a bending structure that can bend the finger towards the palm surface of the palm (1).

4. The manipulator with movable fingers according to claim 3, characterized in that: The bending structure is a flexible member (7) capable of deforming. A plurality of partition grooves (72) are provided at intervals along the length direction on the first side wall (71) of the flexible member (7) facing away from the palm surface of the palm (1), so as to divide the flexible member (7) into a plurality of units (73). Each of the units (73) is internally hollow, and the units (73) communicate with each other. An air inlet hole (75) communicating with the end unit (73) is formed in the flexible member (7).

5. The manipulator with movable fingers according to claim 4, characterized in that: A hinge structure (8) is provided in the flexible member (7), and the hinge structure (8) extends along the length direction of the flexible member (7). The hinge structure (8) is disposed close to the second side wall (76) of the flexible member (7) facing the palm surface of the palm (1).

6. The manipulator with movable fingers according to claim 5, characterized in that: The hinge structure (8) includes a plurality of links (81) hinged in sequence along the length direction of the flexible member (7). Adjacent two links (81) are connected by a pivot (82), and the axis of the pivot (82) extends along the width direction of the second side wall (76). The pivot (82) is disposed corresponding to the partition groove (72).

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