Omni-directional active finger and dexterous hand

Abstract

This application relates to the field of robotic arm technology, and discloses an omnidirectional movable finger and a dexterous hand, applicable to a dexterous hand with a palm base. The omnidirectional movable finger includes: a finger base, a middle finger, and a fingertip connected to each other; a finger base connecting block, one end of which is connected to the palm base and the other end of which is connected to the finger base, and can swing left and right relative to the palm base; a flexion-extension module, which can simultaneously swing left and right and pitch up and down relative to the palm base, and has an axially extendable drive shaft at the front end, with a fisheye bearing installed at the end of the drive shaft, and the finger base is connected to the fisheye bearing; a proximal link, which drives the middle finger to synchronously couple flexion and extension when the finger base flexes and extends relative to the finger base connecting block; when the omnidirectional movable finger performs swinging and flexion-extension movements simultaneously, the flexion-extension module passively swings through a rotating shaft structure, in conjunction with the adaptive deflection of the finger base connecting block relative to the fisheye bearing, so as to achieve non-interference between the flexion-extension and swinging of the omnidirectional movable finger.

Description

Technical Field

[0001] This application relates to the field of robotic arm technology, and more specifically to an omnidirectional movable finger and dexterous hand. Background Technology

[0002] With the development of robot dexterous hand technology, dexterous hands need to have multi-degree-of-freedom motion capabilities to complete complex operations such as grasping, holding, and pinching.

[0003] For dexterous hand solutions with built-in actuators, where the actuators are located on or near the joints and use direct drive or linkage coupling to achieve finger movements, this approach treats the hand as an independent module, such as a fully master-driven approach. In this case, each rotating joint is equipped with a rotary or linear micro motor. The advantage of this approach is that it can precisely control finger movements and achieve high-precision operation. However, the disadvantages are also obvious. The fully driven joint dexterous hand uses a large number of drive components, resulting in high cost, difficulty in heat dissipation, complex control, high computing power consumption, complex wiring, and relatively poor robustness.

[0004] For dexterous hands that are small in size and lightweight, linkages or tendons can be used to couple one or more degrees of freedom of the fingers with a certain degree of freedom. However, due to the limited number of driving sources, interference between flexion and extension and swinging is likely to occur during finger movement. For example, flexion and extension may occur during finger swinging, or flexion and extension may lead to swinging. In order to avoid motion interference, existing technologies often require the addition of additional decoupling mechanisms, which leads to complex structure, increased size, and increased control difficulty, which is not conducive to the miniaturization and lightweighting of dexterous hands.

[0005] Therefore, how to decouple finger flexion and extension movements from swinging movements within a limited space and structural range, so that the two can be controlled independently and move in coordination, while avoiding motion interference, has become a technical problem that urgently needs to be solved in the design of omnidirectional active fingers for dexterous hands. Summary of the Invention

[0006] The purpose of this application is to provide an omnidirectional movable finger to decouple finger flexion and extension movements from swinging movements within a limited space and structural range.

[0007] Another objective of this application is to provide a dexterous hand that includes the above-mentioned omnidirectional movable fingers and is capable of decoupling finger flexion and extension movements from swinging movements within a limited space and structural range.

[0008] To achieve the above objectives, the technical solution adopted in this application is as follows: An omnidirectional movable finger is provided, comprising: a finger base, a middle finger, and a fingertip connected to each other; a finger base connecting block, one end of which is connected to a palm base, and the other end of which is connected to the finger base, the finger base connecting block being able to swing left and right relative to the palm base; a flexion-extension module, the end of which is connected to the palm base via a pivot structure, the flexion-extension module being able to simultaneously oscillate left and right and pitch up and down relative to the palm base, the front end of the flexion-extension module being provided with an axially extendable drive shaft, the end of which is equipped with a fisheye bearing, the finger base and... The fisheye bearing is connected by a proximal link, one end of which is connected to the finger base connecting block, and the other end is connected to the middle finger. Thus, the finger base connecting block, the finger base, the proximal link, and the middle finger form a planar four-bar linkage. When the finger base flexes or extends relative to the finger base connecting block, the middle finger is driven to flex and extend synchronously through the proximal link. Therefore, when the omnidirectional movable finger performs swinging and flexion / extension movements simultaneously, the flexion / extension module is passively deflected through the rotating shaft structure, in conjunction with the adaptive deflection of the finger base connecting block relative to the fisheye bearing, to achieve non-interference between the flexion / extension and swinging of the omnidirectional movable finger.

[0009] As a preferred embodiment, it also includes a distal link, one end of which connects the finger base to the middle of the finger, and the other end of which connects the middle of the finger to the fingertip. When the middle of the finger flexes and extends, the distal link drives the fingertip to flex and extend synchronously, thereby giving the omnidirectional movable finger three degrees of freedom of flexion and extension and one degree of freedom of swing.

[0010] Furthermore, this application also provides a dexterous hand, including a plurality of omnidirectional movable fingers and a palm base as described above, wherein the plurality of omnidirectional movable fingers are movably disposed on the palm base.

[0011] As a preferred embodiment, the dexterous hand further includes flexion-extension movable fingers; the dexterous hand has three omnidirectional movable fingers, namely the index finger, ring finger, and little finger. The index finger is movably connected to the palm base via an index finger base connecting block, the ring finger is connected to the palm base via a ring finger base connecting block, and the little finger is connected to the palm base via a little finger base connecting block; the flexion-extension movable finger is the middle finger, specifically including a middle finger base, a middle finger middle section, and a middle finger tip, with the middle finger base directly rotatably connected to the hand. The palm base; the flexion-extension movable finger further includes a first connector and a second connector, one end of the first connector is connected to the base of the middle finger and the other end is connected to the middle of the middle finger, one end of the second connector is connected to the base of the middle finger and the middle of the middle finger, and the other end is connected to the tip of the middle finger and the middle of the middle finger, so that the tip of the middle finger can flex and extend relative to the middle of the middle finger, the middle of the middle finger can flex and extend relative to the base of the middle finger, and the base of the middle finger can flex and extend relative to the palm base, so that the flexion-extension movable finger has three degrees of freedom of flexion and extension.

[0012] As a preferred embodiment, the first connector is a middle finger flexion-extension module, which is disposed within the base of the middle finger. The end of the middle finger flexion-extension module is provided with a telescopic shaft, which is connected to the middle finger to drive the middle finger to flex and extend relative to the base of the middle finger. The flexion and extension of the middle finger is controlled only by the middle finger flexion-extension module, thereby enabling the middle finger to actively flex and extend relative to the base of the middle finger.

[0013] As another preferred embodiment, the finger flexion-extension module further includes a motor and a gear assembly. The motor is arranged in parallel with the telescopic shaft of the finger flexion-extension module, and the motor is connected to the telescopic shaft of the finger flexion-extension module through the gear assembly.

[0014] As another preferred embodiment, the device also includes a swing module disposed within the palm base. The swing module is connected to the index finger base connecting block, the ring finger base connecting block, and the little finger base connecting block to drive the index finger, ring finger, and little finger to perform opening and closing movements.

[0015] Further preferably, the swing module includes a geared motor, a coupling, a ball screw, and a connecting rod assembly. The output shaft of the geared motor is connected to the ball screw via the coupling. The ball screw is connected to the connecting rod assembly, which is connected to the index finger base connecting block, the ring finger base connecting block, and the little finger base connecting block, respectively. The geared motor drives the ball screw to move linearly via the coupling, which in turn drives the connecting rod assembly to reciprocate, thereby enabling the index finger, ring finger, and little finger to open and close.

[0016] Further preferably, the connecting rod assembly includes a first connecting rod, a second connecting rod, and a third connecting rod. One end of the first connecting rod is connected to the ball screw, and the other end is connected to the ring finger base connecting block. One end of the second connecting rod is connected to the ring finger base connecting block, and the other end is connected to the little finger base connecting block. One end of the third connecting rod is connected to the ring finger base connecting block, and the other end is connected to the index finger base connecting block. The index finger base connecting block has an index finger swing shaft hole and is oscillatingly connected to the palm base through the index finger swing shaft hole. The ring finger base connecting block has a ring finger swing shaft hole and is oscillatingly connected to the palm base through the ring finger swing shaft hole. The palm base is oscillatingly connected, and the little finger base connecting block is provided with a little finger oscillating shaft hole, and is oscillatingly connected to the palm base through the little finger oscillating shaft hole; in the palm plane of the palm base, the line connecting the index finger oscillating shaft hole and the ring finger oscillating shaft hole intersects the third connecting rod, and the line connecting the ring finger oscillating shaft hole and the little finger oscillating shaft hole does not intersect the second connecting rod, so that the oscillating directions of the index finger base connecting block and the ring finger base connecting block are opposite, and the oscillating directions of the ring finger base connecting block and the little finger base connecting block are the same, thereby the index finger, the ring finger and the little finger can cooperate with the middle finger to realize the four-finger opening and closing action.

[0017] Further preferably, the third connecting rod includes a first end and a second end, the first end is connected to the index finger base connecting block, the second end is connected to the ring finger base connecting block, the rod segment at the first end and the rod segment at the second end are bent relative to each other, so that the third connecting rod is bent, and the axis of the rod segment at the first end and the axis of the rod segment at the second end are set at an obtuse angle.

[0018] Compared with the prior art, the beneficial effects of this application are as follows: Omnidirectional movable fingers: Eliminate over-constraint between flexion-extension drive and swing drive, reduce additional bending moment, lateral force and wear at the connection points of drive shaft, fisheye bearing, finger base connecting block and planar four-bar linkage, improve the smoothness, reliability and service life of omnidirectional movable fingers compound motion, and enable the index, ring and little fingers to swing while realizing multi-joint coupled flexion-extension, which facilitates independent control and coordinated action, and improves the adaptability of dexterous hands to grasp, hold and perform complex operations.

[0019] Dexterous hand: The dexterous hand of this application adopts the above-mentioned omnidirectional movable finger, and therefore has the beneficial effects of the above-mentioned omnidirectional movable finger, which will not be repeated here. Attached Figure Description

[0020] Figure 1 A schematic diagram of the structure of a dexterous hand; Figure 2 This is a cross-sectional view of the structure of the middle phalanges of the index finger in their unbent state. Figure 3 A cross-sectional view of the structure of the phalanges of the index finger in a bent state; Figure 4 This is a cross-sectional view of the middle finger. Figure 5 A schematic diagram of the structure of an omnidirectional movable finger in an extended state in conjunction with a flexion-extension movable finger; Figure 6 A schematic diagram of the structure of an omnidirectional movable finger in a closed state in conjunction with a flexion-extension movable finger; Figure 7 This is a schematic diagram of the structure of each component in the omnidirectional movable finger and the flexion-extension movable finger; Figure 8 This is a structural diagram showing the location of the base connecting block.

[0021] In the diagram: 1. Dexterous hand; 2. Thumb; 3. Index finger; 4. Middle finger; 5. Ring finger; 6. Little finger; 10. Hand base; 21. Index finger base; 22. Middle finger base; 23. Ring finger base; 24. Little finger base; 31. Middle index finger; 32. Middle middle middle finger; 33. Middle ring finger; 34. Middle little finger; 41. Index fingertip; 42. Middle fingertip; 43. Ring fingertip; 44. Little fingertip; 50. Flexion-extension module; 51. Drive shaft; 52. Fisheye bearing; 60. Rotary shaft structure; 61. Left and right rotating shafts; 62. Pitch rotating shaft; 70. Proximal link; 80. Distal link; 90. First connecting piece; 92. Middle finger flexion... 93. Telescopic shaft of extension module; 94. Motor; 100. Gear assembly; 111. Second connecting piece; 112. Swing module; 113. Gear motor; 114. Coupling; 115. Ball screw; 116. Connecting rod assembly; 117. First connecting rod; 118. Second connecting rod; 119. Third connecting rod; 120. First end; 121. Second end; 122. Index finger base connecting block; 123. Ring finger base connecting block; 124. Little finger base connecting block; 125. Index finger swing shaft hole; 126. Ring finger swing shaft hole; 127. Little finger swing shaft hole; 128. Arc-shaped groove; 129. Torsion spring mounting groove. Detailed Implementation

[0022] The present application will be further described below with reference to specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0023] In the description of this application, it should be noted that the directional terms such as "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limiting the specific protection scope of this application.

[0024] It should be noted that the terms "first," "second," etc., in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0025] The terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0026] In a preferred embodiment, see Figures 1 to 8 This embodiment provides a dexterous hand 1, including a palm base 10 and four fingers arranged side by side on the palm base 10, and a thumb 2 located on the side of the palm base 10. The four fingers are divided into two categories according to their degrees of freedom of movement: three are omnidirectional fingers, namely the index finger 3, the ring finger 5, and the little finger 6; and one is a flexion-extension finger, namely the middle finger 4. Both omnidirectional and flexion-extension fingers include three phalanges: the base, the middle, and the tip. Correspondingly, the three phalanges of the index finger 3 are the base 21, the middle 31, and the tip 41; the three phalanges of the ring finger 5 are the base 23, the middle 33, and the tip 43; the three phalanges of the little finger 6 are the base 24, the middle 34, and the tip 44; and the three phalanges of the middle finger 4 are the base 22, the middle 32, and the tip 42.

[0027] Meanwhile, the finger base connecting blocks are only set for omnidirectional movable fingers. The finger base connecting blocks include index finger base connecting block 121, ring finger base connecting block 122 and little finger base connecting block 123, which correspond to index finger 3, ring finger 5 and little finger 6 respectively. One end of index finger base connecting block 121 is used to connect to palm base 10 and the other end is connected to index finger base 21. Similarly, one end of ring finger base connecting block 122 is used to connect to palm base 10 and the other end is connected to ring finger base 23. One end of little finger base connecting block 123 is used to connect to palm base 10 and the other end is connected to little finger base 24. Index finger base connecting block 121, ring finger base connecting block 122 and little finger base connecting block 123 can all swing left and right relative to palm base 10.

[0028] Each of the index finger 3, ring finger 5, and little finger 6 is equipped with a flexion-extension module 50. The end of the flexion-extension module 50 is connected to the palm base 10 through a pivot structure 60. The pivot structure 60 includes a left-right pivot 61 with its axis perpendicular to the palm plane of the palm base 10, and a pitch pivot 62 with its axis parallel to the palm plane of the palm base 10, so that the flexion-extension module 50 can simultaneously swing left and right and pitch up and down relative to the palm base 10.

[0029] The overall structure and driving method of the three omnidirectional movable fingers are the same. The following will take the index finger as an example to explain in detail the specific structure, working principle and movement process of the omnidirectional movable fingers.

[0030] like Figure 2 As shown, the index finger base 21 of the index finger 3 is rotatably connected to the palm base 10 through the index finger base connecting block 121. The finger base connecting block can swing left and right relative to the palm base 10, providing the index finger 3 with a lateral swing degree of freedom relative to the palm base 10. The index finger 3 is equipped with a set of flexion and extension modules 50. The end of the flexion and extension module 50 is connected to the palm base 10 through a rotating shaft structure 60. The rotating shaft structure 60 includes a left and right rotating shaft 61 with its axis perpendicular to the palm plane of the palm base 10, and a pitch rotating shaft 62 with its axis parallel to the palm plane of the palm base 10, so that the flexion and extension module 50 can simultaneously achieve left and right swing and up and down pitch rotation relative to the palm base 10. The front end of the flexion-extension module 50 is provided with an axially extendable drive shaft 51, and the end of the drive shaft 51 is equipped with a fisheye bearing 52. The index finger base 21 of the index finger 3 is connected to the fisheye bearing 52 for transmission. Preferably, a drive motor is provided inside the flexion-extension module 50 to control the extension and retraction of the drive shaft 51.

[0031] Furthermore, if the flexion-extension module 50 is rigidly fixed to the palm base 10, when the index finger base connecting block 121 drives the index finger 3 to swing left and right, the relative angle between the drive shaft 51 and the index finger base 21 will change. Forced lateral bending or torsion will occur between the drive shaft 51 and the fisheye bearing 52, resulting in motion interference. Therefore, whether the flexion-extension movement can be carried out independently depends on whether the flexion-extension module 50 as a whole and the end of its drive shaft 51 can generate corresponding passive angle compensation with the composite movement posture of the index finger 3. Therefore, the pivot structure 60 includes a left-right pivot 61 with its axis perpendicular to the palm plane of the palm base 10, and a pitch pivot 62 with its axis parallel to the palm plane of the palm base 10. The left-right pivot 61 allows the flexion-extension module 50 to sway left and right relative to the palm base 10, and the pitch pivot 62 allows the flexion-extension module 50 to pitch up and down relative to the palm base 10. Thus, the installation of the flexion-extension module 50 on the palm base 10 is not a fixed constraint, but has a passive adaptability in both left-right sway and up-down pitch directions. When the index finger base connecting block 121 swings left and right relative to the palm base 10, the flexion-extension module 50 can passively sway with the left and right swing posture of the finger through the left and right rotation axis 61; when the flexion and extension of the index finger 3 causes the vertical angle between the flexion-extension module 50 and the index finger base 21 to change, the flexion-extension module 50 can passively pitch through the pitch rotation axis 62. In other words, the flexion-extension module 50 as a whole can adjust with the swing and flexion-extension combined posture of the index finger 3, rather than forcing the finger to move according to the fixed posture of the flexion-extension module 50.

[0032] The fisheye bearing 52 allows the index finger base 21 to adaptively deflect relative to the drive shaft 51 in conjunction with the index finger base connecting block 121. When the index finger base connecting block 121 swings left and right, the index finger base 21 flexes or extends relative to the index finger base connecting block 121, or both occur simultaneously, the change in the angle between the index finger base 21 and the drive shaft 51 can be absorbed by the fisheye bearing 52. During flexion and extension drive, while transmitting the axial extension and retraction of the drive shaft 51 to the index finger base 21, the lateral displacement and angle change generated by the swinging motion are not transmitted in the opposite direction as forced bending of the index finger base 21.

[0033] Preferably, the omnidirectional phalanx is also equipped with a proximal link 70 and a distal link 80 for synchronously coupled flexion and extension of multiple phalanges under a single drive source. Taking the index finger 3 as an example, one end of the proximal link 70 is connected to the index finger base connecting block 121, and the other end is connected to the index finger middle 31, so that the index finger base connecting block 121, the index finger base 21, the proximal link 70 and the index finger middle 31 together form a planar four-bar linkage; when the flexion and extension module 50 drives the index finger base 21 to flex and extend relative to the index finger base connecting block 121, the proximal link 70 drives the index finger middle 31 to synchronously coupled flex and extend, thereby reducing the number of independent drives and maintaining motion coordination. One end of the distal link 80 connects to the hinge between the index finger base 21 and the index finger middle 31, and the other end connects to the hinge between the index finger middle 31 and the index finger tip 41. When the index finger middle 31 flexes or extends relative to the index finger base 21, the distal link 80 transmits the movement of the middle finger to the finger tip, causing the index finger tip 41 to synchronously couple flexion and extension relative to the index finger middle 31. Thus, driven by a single flexion and extension module 50, the index finger 3 can form a continuous flexion and extension kinematic chain between the three phalanges of the index finger base 21, the index finger middle 31, and the index finger tip 41, possessing three degrees of freedom in flexion and extension. Combined with the one degree of freedom in lateral swing provided by the index finger base connecting block 121, it can complete a relatively rich range of flexion, extension, and opening / closing movements. Through the linkage design of the proximal link 70 and the distal link 80, the linked flexion and extension of the index finger tip 41 can be achieved without adding an additional drive source, simplifying the finger transmission structure, reducing control complexity, and improving the biomimetic degree and range of motion of the finger movement.

[0034] See Figure 2 At this time, the index finger 3 is in an unbent state. The flexion-extension module 50 corresponding to the index finger 3 keeps the drive shaft 51 in a position that keeps the index finger 3 extended. The fisheye bearing 52 at the end of the drive shaft 51 is connected to the index finger base 21 via a connecting shaft. The index finger base 21 remains extended relative to the index finger base connecting block 121. The proximal link 70 forms a planar four-bar linkage between the index finger base connecting block 121, the index finger base 21, and the middle of the index finger 31, keeping the middle of the index finger 31 extended relative to the index finger base 21. The distal link 80 maintains a transmission relationship between the index finger base 21 and the middle of the index finger 31, and between the middle of the index finger 31 and the index finger tip 41, keeping the index finger tip 41 extended relative to the middle of the index finger 31. Thus, the index finger base 21, the middle of the index finger 31, and the index finger tip 41 extend in a basically straight line direction, forming Figure 2 The unbent state shown allows the omnidirectional fingers to perform actions such as opening, releasing, approaching objects, or cooperating with other fingers to form a larger envelope space.

[0035] like Figure 3As shown, the index finger 3 is in a bent state at this time. At this time, the flexion-extension module 50 corresponding to the index finger 3 operates, the drive shaft 51 extends or retracts axially, and the fisheye bearing 52 at the end of the drive shaft 51 drives the index finger base 21 to flex and extend relative to the finger base connecting block via the connecting shaft. When the index finger base 21 flexes and extends, the proximal connecting rod 70 forms a planar four-bar linkage between the index finger base connecting block 121, the index finger base 21, and the index finger middle 31, thereby driving the index finger middle 31 to synchronously couple flex and extend relative to the index finger base 21. When the index finger middle 31 flexes and extends, the distal connecting rod 80 transmits motion between the index finger base 21 and the index finger middle 31, and between the index finger middle 31 and the index finger tip 41, thereby driving the index finger tip 41 to synchronously couple flex and extend relative to the index finger middle 31. Thus, the index finger base 21, the middle finger, and the index finger tip 41 bend sequentially, forming... Figure 3 The diagram shows the bending states of each finger joint. At this time, the flexion-extension module 50 is connected to the palm base 10 via a rotating shaft structure 60, which includes a left-right rotating shaft 61 and a pitch rotating shaft 62. When the index finger 3 simultaneously swings and flexes / extensions, the flexion-extension module 50 passively deflects via the left-right rotating shaft 61 and the pitch rotating shaft 62, while one side of the drive shaft 51 adaptively deflects via a fisheye bearing 52, ensuring that the flexion / extension and swinging of the index finger 3 do not interfere with each other. Figure 3 The bending states of each finger joint shown enable the index finger 3 to envelop, hook, or press on objects, improving the ability of the omnidirectional finger to grasp, hold, and manipulate objects. Through the cooperation of the proximal link 70, the distal link 80, the fisheye bearing 52, and the finger base connecting block, the index finger 3, as well as the ring finger 5 and the little finger 6, can maintain coordinated movement of multiple finger joints during bending.

[0036] Further, see Figure 8 Taking the index finger base connecting block 121 as an example, the following description of the structure of the index finger base connecting block 121 can also be applied to the ring finger base connecting block 122 and the little finger base connecting block 123; wherein an arc-shaped groove 127 is provided on the side wall of the index finger base connecting block 121 that extends toward the drive shaft 51 of the flexion and extension module 50. The arc-shaped groove 127 extends in a cylindrical shape along the movement trajectory of the flexion-extension module 50 around the rotating shaft structure 60 along the drive shaft 51. The groove width is slightly larger than the shaft diameter of the drive shaft 51. When the index finger 3 performs a combined flexion-extension and swinging motion, the flexion-extension module 50 drives the drive shaft 51 to swing left and right and pitch up and down synchronously. The shaft of the drive shaft 51 sweeps through the arc-shaped groove 127. The internal cavity of the arc-shaped groove 127 provides clearance space for the full stroke movement of the drive shaft 51, avoiding scraping interference between the drive shaft 51 and the finger base connecting block. At the same time, the two side walls of the arc-shaped groove 127 can limit the radial movement of the drive shaft 51, reduce the lateral sway of the drive shaft 51, and maintain the transmission fit accuracy between the fisheye bearing 52 at the end of the drive shaft 51 and the finger base.

[0037] Meanwhile, the index finger base connecting block 121 has a torsion spring mounting groove 128 on its side at the part where it is rotatably connected to the index finger base 21. The torsion spring mounting groove 128 is coaxially arranged with the hinge shaft between the two. The groove is recessed inward along the axial direction of the rotation shaft. The reset torsion spring is sleeved on the rotation shaft. The helical body of the torsion spring is embedded in the torsion spring mounting groove 128. One end of the torsion spring is locked against the inner wall limiting structure of the torsion spring mounting groove 128, and the other end abuts against the root end face of the index finger base 21. When the index finger base 21 flexes and extends relative to the index finger base connecting block 121, the reset torsion spring elastically deforms synchronously with the deflection of the finger base, continuously providing a reset preload force to the index finger base 21, maintaining the initial extension posture of the index finger 3 under no-load conditions; at the same time, it can eliminate the fit gap at the hinge, reduce the motion return error, and improve the smoothness of the flexion and extension response of the index finger 3.

[0038] Preferably, a return torsion spring can be provided at the rotational connection between the finger base and the middle of the finger, or even between the middle of the finger and the fingertip.

[0039] Furthermore, the specific structure and working principle of the flexion-extension finger, namely the middle finger (4), will be explained in detail below. See also... Figure 4 The middle finger 4 is a finger with only flexion and extension freedom, but no left or right lateral swing freedom. The finger base 22 is directly rotatably connected to the palm base 10 without a finger base connecting block. The middle finger 4 is also equipped with a flexion and extension module 50, which is connected to the middle finger base 22 through a drive shaft 51 at the end of the flexion and extension module 50. The end of the drive shaft 51 at the middle finger 4 can be equipped with a fisheye bearing 52. Since the middle finger 4 does not need to swing, a pin hole can be used directly in the specific implementation. From a cost perspective, the fisheye bearing 52 can be directly used without replacing the parts.

[0040] The middle finger 4 is also equipped with a first connector 90 and a second connector 100. The specific structures of the first connector 90 and the second connector 100 differ from those of the aforementioned proximal link 70 and distal link 80. One end of the first connector 90 is connected to the middle finger base 22, and the other end is connected to the middle finger 32. One end of the second connector 100 is connected to the hinge between the middle finger base 22 and the middle finger 32, and the other end is connected to the hinge between the middle finger tip 42 and the middle finger 32. Thus, the middle finger tip 42 can flex and extend relative to the middle finger 32, the middle finger 32 can flex and extend relative to the middle finger base 22, and the middle finger base 22 can flex and extend relative to the palm base 10, so that the middle finger 4 has three degrees of freedom of flexion and extension.

[0041] In one preferred embodiment, the first connector 90 is a middle finger flexion and extension module, which is disposed inside the middle finger base 22. The end of the middle finger flexion and extension module is provided with a middle finger flexion and extension module telescopic shaft 92, which is connected to the middle finger 32 for transmission, so as to drive the middle finger 32 to flex and extend relative to the middle finger base 22. At this time, the flexion-extension module 50 located in the palm base 10 is connected to the middle finger base 22 and drives only the middle finger base 22 to flex and extend relative to the palm base 10. The middle finger flexion-extension module and the flexion-extension module 50 located in the palm base 10 are independent driving sources, so that the flexion and extension of the middle finger 32 is controlled only by the middle finger flexion-extension module, and the flexion and extension of the middle finger base 22 is controlled only by the flexion-extension module 50 located in the palm base 10. Thus, the middle finger base 22 and the middle finger 32 can actively flex and extend respectively, improving the independence, flexibility and richness of movement of the middle finger 4, and enabling the dexterous hand 1 to have better adaptability in complex grasping and operation processes.

[0042] Furthermore, the finger flexion-extension module also includes a motor 93 and a gear assembly 94. The motor 93 is arranged in parallel with the telescopic shaft 92 of the finger flexion-extension module, that is, the axis of the motor 93 is parallel to the axis of the telescopic shaft 92 of the finger flexion-extension module. The motor 93 is connected to the telescopic shaft 92 of the finger flexion-extension module through the gear assembly 94. Specifically, the motor 93 serves as the power source, and the gear assembly 94 is used to transmit the rotational motion of the motor 93 to the telescopic shaft 92 of the finger flexion-extension module. The motor 93 and the telescopic shaft 92 of the finger flexion-extension module are arranged side by side rather than coaxially connected in series. The motion output by the motor 93 is converted into the telescopic motion of the telescopic shaft 92 of the finger flexion-extension module after passing through the gear assembly 94. Because the motor 93 and the telescopic shaft 92 of the middle finger flexion and extension module are arranged in parallel, the height of the middle finger flexion and extension module in the vertical direction is reduced. While meeting the extension and retraction requirements of the telescopic shaft 92 of the middle finger flexion and extension module, the middle finger flexion and extension module can be accommodated within the middle finger base 22. At the same time, the middle finger flexion and extension module can be compactly arranged in a limited space, which not only ensures that the telescopic shaft 92 of the middle finger flexion and extension module has the required extension and retraction stroke, but also reduces the height of the middle finger flexion and extension module in the vertical direction, thereby improving the integration and space utilization of the middle finger 4 structure.

[0043] Preferred, see Figures 5 to 7 The dexterous hand 1 in this embodiment also includes a swing module 110, which is used to synchronously drive the three omnidirectional movable fingers to complete the opening and closing movements. The swing module 110 is disposed in the palm base 10, and the swing module 110 and each flexion and extension module 50 are stacked in a direction perpendicular to the palm plane of the palm base 10, so that the swing module 110 and the flexion and extension modules 50 form an upper and lower stacked spatial layout in the palm base 10, reducing the area occupied by the two in the palm plane direction. Correspondingly, the swing module 110 is also connected to the index finger base connecting block 121, the ring finger base connecting block 122, and the little finger base connecting block 123 to drive the index finger 3, the ring finger 5, and the little finger 6 to perform opening and closing movements.

[0044] Specifically, the swing module 110 includes a geared motor 111, a coupling 112, a ball screw 113, and a connecting rod assembly 114. The output shaft of the geared motor 111 is connected to the ball screw 113 via the coupling 112. The ball screw 113 is connected to the connecting rod assembly 114. The connecting rod assembly 114 is connected to the index finger base connecting block 121, the ring finger base connecting block 122, and the little finger base connecting block 123, respectively. The geared motor 111 drives the ball screw 113 to move linearly via the coupling 112. This, in turn, drives the connecting rod assembly 114 to reciprocate, enabling the index finger 3, ring finger 5, and little finger 6 to open and close. Specifically, the geared motor 111 serves as the power source for the swing module 110. A coupling 112 connects the output shaft of the geared motor 111 to the ball screw 113, transmitting the rotational motion from the geared motor 111 to the ball screw 113. The ball screw 113 is connected to the connecting rod assembly 114, converting the motion of the ball screw 113 into the motion of the connecting rod assembly 114. Through the cooperation of the geared motor 111, coupling 112, ball screw 113, and connecting rod assembly 114, the swing module 110 can stably transmit the motion of the geared motor 111 to the index finger base connecting block 121, ring finger base connecting block 122, and little finger base connecting block 123, thereby achieving the coordinated opening and closing of the index finger 3, ring finger 5, and little finger 6. This design is compact, reliable in transmission, and facilitates integrated arrangement within the palm base 10.

[0045] Preferably, the connecting rod assembly 114 includes a first connecting rod 115, a second connecting rod 116, and a third connecting rod 117. One end of the first connecting rod 115 is connected to the ball screw 113, and the other end is connected to the ring finger base connecting block 122. One end of the second connecting rod 116 is connected to the ring finger base connecting block 122, and the other end is connected to the little finger base connecting block 123. One end of the third connecting rod 117 is connected to the ring finger base connecting block 122, and the other end is connected to the index finger base connecting block 121.

[0046] The index finger base connecting block 121 is provided with an index finger swing shaft hole 124 and is swing-connected to the palm base 10 through the index finger swing shaft hole 124. The ring finger base connecting block 122 is provided with a ring finger swing shaft hole 125 and is swing-connected to the palm base 10 through the ring finger swing shaft hole 125. The little finger base connecting block 123 is provided with a little finger swing shaft hole 126 and is swing-connected to the palm base 10 through the little finger swing shaft hole 126. In the palm plane of the palm base 10, the line connecting the index finger swing shaft hole 124 and the ring finger swing shaft hole 125 intersects the third connecting rod 117, and the line connecting the ring finger swing shaft hole 125 and the little finger swing shaft hole 126 does not intersect the second connecting rod 116, so that the swing directions of the index finger base connecting block 121 and the ring finger base connecting block 122 are opposite, and the swing directions of the ring finger base connecting block 122 and the little finger base connecting block 123 are the same. Thus, the index finger 3, the ring finger 5 and the little finger 6 can cooperate with the middle finger 4 to realize the four-finger opening and closing action.

[0047] Further preferably, the third connecting rod 117 includes a first end 118 and a second end 119. The first end 118 is connected to the index finger base connecting block 121, and the second end 119 is connected to the ring finger base connecting block 122. The rod segments of the first end 118 and the second end 119 are bent relative to each other, making the third connecting rod 117 bend. The axis of the rod segment where the first end 118 is located and the axis of the rod segment where the second end 119 is located are set at an obtuse angle. Specifically, the angle range of this obtuse angle is set to be greater than 90 degrees and less than 140 degrees. It should be noted that if this angle is too large, the third connecting rod 117 will be close to a straight rod, resulting in insufficient directional conversion. The reverse swing angle of the index finger base connecting block 121 may be too small, causing the index finger 3 to not move properly in the extended or closed state, resulting in the four fingers not opening and closing properly. If the angle is too small, the third connecting rod 117 will bend too sharply, resulting in an excessive change in direction. The reverse swing angle of the index finger base connecting block 121 may be too large, causing interference between the index finger 3 and the middle finger 4 or ring finger 5, or even causing the four fingers to collide during the closing process. Similarly, if the third connecting rod 117 is close to a straight rod, although the axial force transmission along the rod direction is more direct, its direction conversion ability is weak. It needs to rely on the hinge structure of the first end 118 and the second end 119 to bear a large lateral constraint force, which can easily make the connecting shaft and shaft hole subject to complex forces. If the angle between the first end 118 and the second end 119 is close to 90 degrees, the direction change at the bend will be drastic. When the force transmitted from the second end 119 turns to the first end 118 at the bend, it will generate a large lateral component force, causing the bend of the third connecting rod 117, the connection of the first end 118, and the connection of the second end 119 to bear a large bending moment and lateral force, increasing the risk of friction, wear, and jamming.

[0048] Therefore, in this embodiment, the angle between the first end 118 and the second end 119 is preferably 125 degrees, so that the third connecting rod 117 can form a suitable swing angle transmission ratio between the ring finger base connecting block 122 and the index finger base connecting block 121, so that the index finger 3 has a suitable swing angle range and angular velocity when swinging in the opposite direction, and coordinates with the swing of the ring finger 5, little finger 6 and middle finger 4. Moreover, through this bending structure, when the third connecting rod 117 connects the ring finger base connecting block 122 and the index finger base connecting block 121, it can adapt to the arrangement space inside the palm base 10, and make the line connecting the third connecting rod 117 with the index finger swing shaft hole 124 and the ring finger swing shaft hole 125 form a cross relationship, which is conducive to realizing the reverse swing of the index finger base connecting block 121 and the ring finger base connecting block 122.

[0049] And specifically, such as Figure 5 As shown, the omnidirectional movable finger is in an extended state. At this time, the swing module 110 is set inside the palm base 10. The reduction motor 111 in the swing module 110 drives the ball screw 113 to move through the coupling 112. The ball screw 113 retracts to the left and drives the connecting rod assembly 114 to move. The first connecting rod 115 in the connecting rod assembly 114 drives the ring finger base connecting block 122 to swing clockwise around the ring finger swing shaft hole 125. The ring finger base connecting block 122 drives the index finger base connecting block 121 to swing counterclockwise around the index finger swing shaft hole 124 through the third connecting rod 117, and drives the little finger base connecting block 123 to swing clockwise around the little finger swing shaft hole 126 through the second connecting rod 116. Thus, the index finger 3, ring finger 5, and little finger 6 are spread apart relative to the middle finger 4, forming the omnidirectional movable finger. Figure 5 The extended state is shown. In the extended state, the flexion-extension module 50 corresponding to the index finger 3, middle finger 4, ring finger 5 and little finger 6 does not interfere with the swing module 110. The middle finger 4 can maintain its corresponding posture through the flexion-extension module 50 and the middle finger flexion-extension module set in the palm base 10. The middle finger base 22, middle finger middle 32 and middle finger tip 42 can be extended or slightly flexed as needed. The same applies to the index finger 3, ring finger 5 and little finger 6, all of which can be controlled by the corresponding flexion-extension module 50 to control their bending state.

[0050] like Figure 6As shown, the omnidirectional movable finger is in the closed state. At this time, the reduction motor 111 in the swing module 110 works in the opposite direction to the unfolded state, driving the ball screw 113 to extend to the right through the coupling 112. The ball screw 113 drives the connecting rod assembly 114 to move in the opposite direction. That is, at this time, the first connecting rod 115 drives the ring finger base connecting block 122 to swing counterclockwise around the ring finger swing shaft hole 125. The ring finger base connecting block 122 drives the index finger base connecting block 121 to swing clockwise around the index finger swing shaft hole 124 through the third connecting rod 117, and drives the little finger base connecting block 123 to swing counterclockwise around the little finger swing shaft hole 126 through the second connecting rod 116. Thus, the index finger 3, ring finger 5, and little finger 6 are brought together or close to each other relative to the middle finger 4, so that the omnidirectional movable finger is formed. Figure 6 The closed state is shown. In the closed state, the flexion-extension module 50 corresponding to the index finger 3 can drive the corresponding index finger base 21, index finger middle 31 and index finger tip 41 to flex and extend. The same applies to the ring finger 5 and the little finger 6. The middle finger 4 adjusts the posture of the middle finger base 22, middle finger middle 32 and middle finger tip 42 through the flexion-extension module 50 and the middle finger flexion-extension module set in the palm base 10, so that the dexterous hand 1 can conform to the surface of the object.

[0051] The basic principles, main features, and advantages of this application have been described above. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this application. Various changes and modifications can be made to this application without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection claimed by this application is defined by the appended claims and their equivalents.

Claims

1. An omnidirectional movable finger, characterized in that, include: The interconnected base, middle, and tip of the fingers; A finger base connecting block, one end of which is used to connect to the palm base, and the other end is connected to the finger base. The finger base connecting block can swing left and right relative to the palm base. The flexion-extension module has its end connected to the palm base via a pivot structure. The flexion-extension module can simultaneously oscillate left and right and pitch up and down relative to the palm base. The front end of the flexion-extension module is provided with an axially extendable drive shaft. A fisheye bearing is installed at the end of the drive shaft, and the finger base is connected to the fisheye bearing via a transmission connection. A proximal link is provided, with one end connected to the finger base connecting block and the other end connected to the middle finger. Thus, the finger base connecting block, the finger base, the proximal link, and the middle finger form a planar four-bar linkage. When the finger base flexes or extends relative to the finger base connecting block, the proximal link drives the middle finger to flex and extend synchronously. Therefore, when the omnidirectional movable finger performs swinging and flexion-extension movements simultaneously, the flexion-extension module passively deflects through the rotating shaft structure, in conjunction with the adaptive deflection of the finger base connecting block relative to the fisheye bearing, so as to achieve non-interference between the flexion-extension and swinging of the omnidirectional movable finger.

2. The omnidirectional movable finger as described in claim 1, characterized in that, It also includes a distal link, one end of which connects the finger base to the middle of the finger, and the other end of which connects the middle of the finger to the fingertip. When the middle of the finger flexes and extends, the distal link drives the fingertip to flex and extend synchronously, so that the omnidirectional movable finger has three degrees of freedom of flexion and extension and one degree of freedom of swing.

3. A dexterous hand, characterized in that, include: Multiple omnidirectional active fingers as described in any one of claims 1-2; And a palm base, wherein a plurality of the omnidirectional movable fingers are movably disposed on the palm base.

4. The dexterous hand as described in claim 3, characterized in that, It also includes flexion and extension of the fingers; The dexterous hand has three omnidirectional movable fingers, namely the index finger, ring finger and little finger. The index finger is movably connected to the palm base through the index finger base connecting block, the ring finger is connected to the palm base through the ring finger base connecting block, and the little finger is connected to the palm base through the little finger base connecting block. The flexion and extension movable finger is the middle finger, and specifically includes the middle finger base, the middle finger middle, and the middle finger tip. The middle finger base is directly rotatably connected to the palm base. The flexion-extension movable finger further includes a first connector and a second connector. One end of the first connector is connected to the base of the middle finger and the other end is connected to the middle of the middle finger. One end of the second connector connects the base of the middle finger and the middle of the middle finger, and the other end connects the tip of the middle finger and the middle of the middle finger. Thus, the tip of the middle finger can flex and extend relative to the middle of the middle finger, the middle of the middle finger can flex and extend relative to the base of the middle finger, and the base of the middle finger can flex and extend relative to the base of the palm, so that the flexion-extension movable finger has three degrees of freedom of flexion and extension.

5. The dexterous hand as described in claim 4, characterized in that, The first connector is a middle finger flexion and extension module, which is disposed in the middle finger base. The end of the middle finger flexion and extension module is provided with a middle finger flexion and extension module telescopic shaft. The middle finger flexion and extension module telescopic shaft is connected to the middle finger to drive the middle finger to flex and extend relative to the middle finger base. The flexion and extension of the middle finger are controlled only by the finger flexion and extension module, thus enabling the middle finger to actively flex and extend relative to the base of the middle finger.

6. The dexterous hand as described in claim 5, characterized in that, The finger flexion-extension module also includes a motor and a gear assembly. The motor is arranged in parallel with the telescopic shaft of the finger flexion-extension module, and the motor is connected to the telescopic shaft of the finger flexion-extension module through the gear assembly.

7. The dexterous hand as described in claim 4, characterized in that, It also includes a swing module, which is disposed in the palm base. The swing module is connected to the index finger base connecting block, the ring finger base connecting block and the little finger base connecting block to drive the index finger, ring finger and little finger to perform opening and closing movements.

8. The dexterous hand as described in claim 7, characterized in that, The swing module includes a geared motor, a coupling, a ball screw, and a connecting rod assembly. The output shaft of the geared motor is connected to the ball screw via the coupling. The ball screw is connected to the connecting rod assembly. The connecting rod assembly is connected to the index finger base connecting block, the ring finger base connecting block, and the little finger base connecting block, respectively. The geared motor drives the ball screw to move linearly through the coupling, which in turn drives the connecting rod assembly to reciprocate, so as to open and close the index finger, the ring finger and the little finger.

9. The dexterous hand as described in claim 8, characterized in that, The connecting rod assembly includes a first connecting rod, a second connecting rod, and a third connecting rod. One end of the first connecting rod is connected to the ball screw, and the other end is connected to the ring finger base connecting block. One end of the second connecting rod is connected to the ring finger base connecting block, and the other end is connected to the little finger base connecting block. One end of the third connecting rod is connected to the ring finger base connecting block, and the other end is connected to the index finger base connecting block. The index finger base connecting block is provided with an index finger swing shaft hole and is swing-connected to the palm base through the index finger swing shaft hole; the ring finger base connecting block is provided with a ring finger swing shaft hole and is swing-connected to the palm base through the ring finger swing shaft hole; the little finger base connecting block is provided with a little finger swing shaft hole and is swing-connected to the palm base through the little finger swing shaft hole. In the palm plane of the hand base, the line connecting the index finger swing shaft hole and the ring finger swing shaft hole intersects the third connecting rod, and the line connecting the ring finger swing shaft hole and the little finger swing shaft hole does not intersect the second connecting rod, so that the swing direction of the index finger base connecting block and the ring finger base connecting block is opposite, and the swing direction of the ring finger base connecting block and the little finger base connecting block is the same, thereby the index finger, the ring finger and the little finger can cooperate with the middle finger to realize the four-finger opening and closing action.

10. The dexterous hand as described in claim 9, characterized in that, The third connecting rod includes a first end and a second end. The first end is connected to the index finger base connecting block, and the second end is connected to the ring finger base connecting block. The rod segment at the first end and the rod segment at the second end are bent relative to each other, so that the third connecting rod is bent. The axis of the rod segment at the first end and the axis of the rod segment at the second end are set at an obtuse angle.

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