A universal finger for a rope-driven dexterous hand and a three-degree-of-freedom dexterous hand finger

Abstract

The application discloses a universal finger for a rope-driven dexterous hand and a three-degree-of-freedom dexterous hand finger, the universal finger comprising a base, a driving assembly, a first driving rope, a second driving rope, an angle sensing assembly and a joint, the first driving rope and the second driving rope being connected with the driving assembly and the joint respectively, the driving assembly being used for driving the first driving rope and the second driving rope to move reversely at the same time, thereby driving the joint to rotate forward or reversely; the angle sensing assembly is used for detecting the rotation angle of the joint; the first driving rope and the second driving rope both comprise a transmission rope and a bendable variable stiffness sleeve, the variable stiffness sleeve being used for limiting and supporting the transmission rope; the transmission rope is connected with the driving end of the driving assembly and the joint; the two ends of the variable stiffness sleeve are connected with a first preset position of the dexterous hand and a second preset position of the dexterous hand respectively. The universal finger for the rope-driven dexterous hand detects the rotation angle of the joint in real time through the angle sensing assembly, forms a closed loop control and improves the accuracy of the finger movement.

Description

Technical Field

[0001] This invention belongs to the field of robotics technology, and in particular relates to a universal finger for a rope-driven dexterous hand and a three-degree-of-freedom dexterous hand finger. Background Technology

[0002] With the continuous development of technology, bionic dexterous hands have demonstrated enormous application potential in numerous fields such as medical rehabilitation, industrial production, aerospace, and service robots. Among them, the rope-driven dexterous hand uses a remote motor to drive a rope, enabling flexible multi-joint movement of the fingers. It combines lightweight design, high degrees of freedom, compliant control, and strong environmental adaptability, making it more suitable for scenarios such as precision grasping and human-robot collaboration. In the design of a rope-driven five-finger dexterous hand, the four fingers other than the thumb are typically defined as universal fingers. These fingers generally employ an identical design and, as the core components of the dexterous hand, play a crucial role in achieving lightweight, modular, and compliant movement of the hand itself, as well as ensuring the safety of human-robot interaction.

[0003] Currently, universal tethered dexterous hands typically require pre-existing drive tether channels within the fingers. This leads to widespread motion and force coupling issues at the joints, posing significant challenges to the movement and force control of the dexterous hand. Furthermore, due to limited internal space, it is usually difficult to integrate angle sensors into universal fingers, making precise control of joint angles challenging.

[0004] Therefore, overcoming the shortcomings of the existing technology is an urgent problem to be solved in this field. Summary of the Invention

[0005] The purpose of this invention is to provide a universal finger for a rope-driven dexterous hand to solve the above-mentioned problems; in addition, this invention also provides a three-degree-of-freedom dexterous hand finger including the above-mentioned universal finger for a dexterous hand.

[0006] To achieve this objective, the present invention adopts the following technical solution: A universal finger for a tethered dexterous hand includes a finger segment, a tethered joint module, and an angle sensor. The tethered joint module includes a base, a drive assembly, a first drive rope, a second drive rope, and a rotatable joint, wherein: A segment of the finger is provided with a joint. The first end of the first drive rope and the first end of the second drive rope are respectively connected to the drive assembly. The second end of the first drive rope and the second end of the second drive rope are respectively connected to the joint. The drive assembly is provided on the base. The drive assembly is configured to drive the first drive rope and the second drive rope to move in opposite directions at the same time, so as to drive the joint to rotate in the forward or reverse direction, thereby driving the finger segment to rotate. An angle sensing component is mounted on the joint and is configured to detect the rotation angle of the joint. Both the first and second drive ropes include a transmission rope and a flexible variable stiffness sleeve. The transmission rope passes through the inner hole of the variable stiffness sleeve, and both the first and second ends of the transmission rope extend out of the variable stiffness sleeve. The variable stiffness sleeve is configured to limit and support the transmission rope. The first end of the transmission rope is detachably connected to the drive end of the drive assembly, and the second end of the transmission rope is detachably connected to the joint. The first end of the variable stiffness sleeve is provided with a first connecting part, and the second end of the variable stiffness sleeve is provided with a second connecting part. The first connecting part is detachably connected to the first preset position of the dexterous hand, and the second connecting part is detachably connected to the second preset position of the dexterous hand.

[0007] Optionally, the angle sensing assembly includes an angle sensor and a drive belt, the angle sensor being connected to the joint via the drive belt, and the angle sensor being configured to detect the rotation angle of the joint.

[0008] Optionally, the variable stiffness sleeve is made by tightly winding a single flat or round steel wire into a spiral tube.

[0009] Optionally, the variable stiffness sleeve includes a high stiffness section and a low stiffness section. The high stiffness section is configured to form the planned path of the transmission rope, and the low stiffness section is configured to bend or straighten together with the transmission rope. The outer diameter of the high stiffness section is larger than the outer diameter of the low stiffness section, and the low stiffness section is a flexible body.

[0010] Optionally, the drive assembly includes a drive member and a transmission assembly. The drive member is disposed at the bottom of the base, and the transmission assembly is disposed inside the base. The transmission assembly includes a rotating shaft, a first guide member, and a second guide member. The rotating shaft is rotatably disposed on the base. The first guide member and the second guide member are respectively disposed on both sides of the rotating shaft. The first end of the first drive rope is wound around the first end of the rotating shaft, and the first end of the second drive rope is wound around the second end of the rotating shaft. The winding directions of the first end of the first drive rope and the first end of the second drive rope are opposite. The second end of the first drive rope is connected to the first fixing part of the joint via the first guide member, and the second end of the second drive rope is connected to the second fixing part of the joint via the second guide member. The drive end of the drive member is connected to one end of the rotating shaft. The drive member is configured to drive the rotating shaft to rotate forward or backward along its own axis to drive the first drive rope and the second drive rope to tighten or loosen, thereby driving the joint to rotate forward or backward.

[0011] Optionally, guide portions are provided at both ends of the rotating shaft, and guide slopes are provided on both sides of the guide portions.

[0012] Optionally, the guide portion has a first mounting hole, a pretensioner is provided in the first mounting hole, the pretensioner has a second mounting hole, a fixing member is provided in the second mounting hole, and the fixing member is configured to fix the first end of the first drive rope or the first end of the second drive rope.

[0013] Optionally, the pretensioner is rotatably disposed in the first mounting hole, and a pretensioning groove is provided on the pretensioner. The first end of the first drive rope or the first end of the second drive rope passes around the rotating shaft and through the pretensioning groove to be fixedly connected to the fixing member. The pretensioner is configured to adjust the tension of the first drive rope or the second drive rope.

[0014] Optionally, a first through hole and a second through hole are provided at the second preset position. Both the first through hole and the second through hole are provided with clearance grooves on their sides. The clearance grooves are connected to the first through hole or the second through hole. The clearance grooves are configured to allow clearance from the first drive rope or the second drive rope. Fasteners are provided in the clearance grooves. The fasteners are configured to press the end of the variable stiffness sleeve in the first through hole or the second through hole.

[0015] A three-degree-of-freedom dexterous hand finger, characterized in that the three-degree-of-freedom dexterous hand finger includes a base, a universal finger joint, a first finger segment, a second finger segment, a third finger segment, a linkage, a first cable-driven joint module, a second cable-driven joint module, and a third cable-driven module, wherein: The first end of the first finger segment is mounted on the base via a universal finger joint. The base is provided with a first joint, the universal finger joint is provided with a second joint, the first finger segment is provided with a third joint, the third finger segment is provided with a fourth joint, and a linkage is provided between the third joint and the fourth joint. The first rope drive module is configured to drive the first joint to rotate forward or backward, the second rope drive module is configured to drive the second joint to rotate forward or backward, and the third rope drive module is configured to drive the fourth joint to rotate forward or backward. The first finger segment, the second finger segment, and the third finger segment all include the aforementioned universal finger. The first finger segment is provided with a first angle sensing component, a second angle sensing component and a third angle sensing component, which are configured to detect the rotation angles of the first joint, the second joint and the fourth joint, respectively.

[0016] The beneficial effects of this invention are as follows: Compared with the prior art, the rope-driven joint module for dexterous hands provided by this invention has the following beneficial effects: 1. This universal finger for rope-driven dexterous hands achieves forward and reverse rotation of the joint by a single drive component through the first and second drive ropes wound in opposite directions at both ends of the pivot. It has a compact structure and fast transmission response. The variable stiffness sleeve provides limiting support for the drive rope to prevent the rope from deviating and winding, thus ensuring transmission accuracy. The angle sensing component detects the joint rotation angle in real time to form a closed-loop control and improve the accuracy of finger movement. 2. The angle sensing component is connected to the joint via a transmission belt. The angle sensor collects the joint rotation angle data in real time. The flexible connection of the transmission belt can adapt to the joint rotation movement and avoid interference or wear caused by the rigid connection between the sensor and the joint. The real-time feedback of the angle data can realize precise closed-loop control of the joint movement, correct movement deviations in time, and ensure the consistency of finger grasping, operation and other actions. 3. The variable stiffness sleeve is made of a single flat or round steel wire tightly wound into a spiral tube. The spiral structure gives the sleeve a flexible characteristic, which can adapt to the multi-angle movement of the joint. At the same time, the tightly wound steel wire ensures the structural strength of the sleeve, which can provide stable guiding support for the transmission rope, prevent the transmission rope from being stretched or swinging due to force, and extend the service life of the rope. Attached Figure Description

[0017] To more clearly illustrate and understand the technical solutions in the embodiments of the present invention, the accompanying drawings used in the background technology and embodiment descriptions of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of a universal finger for a rope-driven dexterous hand according to the present invention; Figure 2 This is a schematic diagram of the structure of the first and second drive ropes in a universal finger for a rope-driven dexterous hand according to the present invention. Figure 3 This is a schematic diagram of the structure of a universal finger drive component for a rope-driven dexterous hand according to the present invention; Figure 4 This is a schematic diagram of the structure of a three-degree-of-freedom dexterous hand finger according to the present invention; Figure 5 This is a side view of the fingers of a three-degree-of-freedom dexterous hand according to the present invention. Detailed Implementation

[0019] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Please see Figures 1 to 5As shown, this embodiment provides a universal finger for a lanyard-driven dexterous hand, comprising a finger segment, a lanyard-driven joint module, and an angle sensor 50. The lanyard-driven joint module includes a base 10, a drive assembly 20, a first drive rope 30, a second drive rope 40, and a rotatable joint 60. One end of the finger segment is provided with the joint 60. The first ends of the first drive rope 30 and the second drive rope 40 are respectively connected to the drive assembly 20, and the second ends of the first drive rope 30 and the second drive rope 40 are respectively connected to the joint 60. The drive assembly 20 is disposed on the base 10 and is configured to drive the first drive rope 30 and the second drive rope 40 to move in opposite directions simultaneously, thereby driving the joint 60 to rotate forward or in the opposite direction, and thus driving the finger segment to rotate. The angle sensor 50 is disposed on the joint 60 and transmits angles... The sensing component 50 is configured to detect the rotation angle of the joint 60; both the first drive rope 30 and the second drive rope 40 include a transmission rope 31 and a flexible variable stiffness sleeve 32. The transmission rope 31 passes through the inner hole of the variable stiffness sleeve 32, and both the first end and the second end of the transmission rope 31 extend out of the variable stiffness sleeve 32. The variable stiffness sleeve 32 is configured to limit and support the transmission rope 31; the first end of the transmission rope 31 is detachably connected to the drive end of the drive component 20, and the second end of the transmission rope 31 is detachably connected to the joint 60; the first end of the variable stiffness sleeve 32 is provided with a first connecting portion 33, and the second end of the variable stiffness sleeve 32 is provided with a second connecting portion 34. The first connecting portion 33 is detachably connected to a first preset position of the dexterous hand, and the second connecting portion 34 is detachably connected to a second preset position of the dexterous hand.

[0021] Specifically, one joint 60 corresponds to one knuckle groove wheel, and the knuckle groove wheel is provided with two fixing parts to connect the second end of the first drive rope 30 and the second end of the second drive rope 40 respectively.

[0022] Specifically, the transmission rope 31 can be a tungsten wire rope or a UHMWPE braided wire.

[0023] Specifically, the first preset position can be a point on the fingers, joints, or palm of a dexterous hand.

[0024] Specifically, the second preset position is located on the drive component 20 of the dexterous hand, which may be on the housing of the drive component 20 or on the drive end of the drive component 20.

[0025] Specifically, the variable stiffness sleeve 32 provides a guide path for the transmission rope 31 and utilizes its own axial deformation stiffness to compensate for possible rope slack, thereby ensuring that the drive rope always remains taut. Before the movement begins, pre-tension is applied to the transmission ropes 31 on both sides, causing the variable stiffness sleeve 32 to deform axially to maintain continuous tension and effectively prevent the "transmission rope 31 slack" phenomenon. One end of the variable stiffness sleeve 32 is fixed near the grooved wheel of the joint 60, and the other end is fixed near the rotating shaft 220, and is placed inside the hollow finger in a naturally extended manner. This design effectively avoids motion interference of the transmission ropes 31 between joints at the mechanical structure level, achieves decoupling of motion and force, eliminates the dependence on complex decoupling algorithms, and improves the accuracy and operating efficiency of the control algorithm.

[0026] As can be seen, the universal finger used for the rope-driven dexterous hand uses the variable stiffness sleeve 32 to limit and support the transmission rope 31, preventing the rope from deviating and tangling, and ensuring transmission accuracy; the angle sensing component 50 detects the joint rotation angle in real time, forming a closed-loop control to improve the accuracy of finger movement; the detachable connection design between the drive rope and the sleeve facilitates maintenance and replacement.

[0027] In one implementation, the angle sensing assembly 50 includes an angle sensor and a drive belt. The angle sensor is connected to the joint 60 via the drive belt and is configured to detect the rotation angle of the joint 60.

[0028] As can be seen, the angle sensing component 50 is connected to the joint via a transmission belt, and uses an angle sensor to collect joint rotation angle data in real time. The flexible connection of the transmission belt can adapt to the rotation of the joint, avoiding interference or wear caused by the rigid connection between the sensor and the joint. The real-time feedback of the angle data can realize precise closed-loop control of the joint movement, correct movement deviations in a timely manner, and ensure the consistency of finger grasping, operation and other actions.

[0029] In one implementation, the variable stiffness sleeve 32 is made by tightly winding a single flat or round steel wire into a spiral tube.

[0030] As can be seen, the variable stiffness sleeve 32 is made of a single flat or round steel wire tightly wound into a spiral tube. The spiral structure gives the sleeve a bendable characteristic, which can adapt to the multi-angle movement of the joint. At the same time, the tightly wound steel wire ensures the structural strength of the sleeve, which can provide stable guiding support for the transmission rope 31, prevent the transmission rope from being stretched or swinging due to force, and extend the service life of the rope.

[0031] In one implementation, the variable stiffness sleeve 32 includes a high stiffness section 320 and a low stiffness section 321. The high stiffness section 320 is configured to form the planned path of the transmission rope 31, and the low stiffness section 321 is configured to bend or straighten together with the transmission rope 31. The outer diameter of the high stiffness section 320 is larger than the outer diameter of the low stiffness section 321, and the low stiffness section 321 is a flexible body.

[0032] Specifically, the ultimate stiffness of the low stiffness section 321 is 15 N / mm, which can meet the bending requirements of the transmission rope 31 below 12.5 N / mm.

[0033] Specifically, the stiffness of the high-stiffness segment 320 is 50 N / mm, and the stiffness of the low-stiffness segment 321 is 12.5 N / mm.

[0034] As can be seen, the high-stiffness section 320 and the low-stiffness section 321 of the variable stiffness sleeve 32 are designed in segments. The high-stiffness section 32 has a large outer diameter and strong rigidity, which can accurately plan the movement path of the transmission rope 31 and ensure that the rope is transmitted along the preset trajectory. The low-stiffness section 321 is a flexible body that can bend and straighten synchronously with the transmission rope and joints without restricting the freedom of movement of the joints. The segmented structure takes into account both transmission stability and movement flexibility, and improves the adaptability of universal fingers.

[0035] In one embodiment, the drive assembly 20 includes a drive member 21 and a transmission assembly 22. The drive member 21 is disposed at the bottom of the base 10, and the transmission assembly 22 is disposed inside the base 10. The transmission assembly 22 includes a rotating shaft 220, a first guide member 221, and a second guide member 222. The rotating shaft 220 is rotatably disposed on the base 10. The first guide member 221 and the second guide member 222 are respectively disposed on both sides of the rotating shaft 220. The first end of the first drive rope 30 is wound around the first end of the rotating shaft 220, and the first end of the second drive rope 40 is wound around the second end of the rotating shaft 220. The first end of the first drive rope 30 and the first end of the second drive rope 40 are wound in opposite directions. The second end of the first drive rope 30 is connected to the first fixing part of the joint 60 via the first guide member 221. The second end of the second drive rope 40 is connected to the second fixing part of the joint 60 via the second guide member 222. The driving end of the drive member 21 is connected to one end of the rotating shaft 220. The drive member 21 is configured to drive the rotating shaft 220 to rotate forward or backward along its own axis, so as to drive the first drive rope 30 and the second drive rope 40 to tighten or loosen, thereby driving the joint 60 to rotate forward or backward.

[0036] Specifically, the driving component 21 is a motor.

[0037] Specifically, both the first guide member 221 and the second guide member 222 are reversing rollers.

[0038] As can be seen, the drive component 21 of the drive assembly 20 drives the rotating shaft to rotate, and the drive ropes wound in opposite directions at both ends of the rotating shaft 220 realize the synchronous tightening or loosening of the two ropes, thereby driving the joint to rotate; the first and second guide components play a guiding and constraining role for the drive ropes, avoiding frictional interference between the ropes and the internal components of the base 10; the design of a single drive component driving two ropes simplifies the drive system, reduces the overall weight and volume of the fingers, and meets the design requirements of lightweight dexterity hands.

[0039] In one embodiment, guide portions 223 are provided at both ends of the rotating shaft 220, and guide slopes are provided on both sides of the guide portions 223.

[0040] As can be seen, the guide slopes at both ends of the rotating shaft 220 can smoothly guide the winding and releasing of the drive rope, avoid rope cutting, and extend the service life of the rope. The transition design of the guide slopes reduces the pre-tension resistance between the rope and the rotating shaft, improves transmission efficiency, and at the same time reduces the wear rate of the rope, extending the service life of the drive rope.

[0041] In one embodiment, the guide portion 223 has a first mounting hole, a pretensioner 224 is provided in the first mounting hole, the pretensioner 224 has a second mounting hole, a fixing member 225 is provided in the second mounting hole, and the fixing member 225 is configured to fix the first end of the first drive rope 30 or the first end of the second drive rope 40.

[0042] Specifically, the preload component 224 is a preload shaft.

[0043] Specifically, fastener 225 is a screw.

[0044] As can be seen, a pretensioner 224 is installed in the first mounting hole of the guide section, and a fixing member 225 passes through the second mounting hole of the pretensioner 224 to fix the end of the drive rope, thereby achieving a reliable connection between the drive rope and the rotating shaft 220. The setting of the pretensioner 224 provides a structural basis for adjusting the tension of the drive rope. The amount of slack in the rope can be eliminated by adjusting the pretensioner, thereby avoiding joint movement lag or positioning deviation caused by rope slack.

[0045] In one embodiment, the pretensioner 224 is rotatably disposed in the first mounting hole. The pretensioner 224 is provided with a pretensioning groove. The first end of the first drive rope 30 or the first end of the second drive rope 40 passes around the rotating shaft 220 and through the pretensioning groove to be fixedly connected to the fixing member 225. The pretensioner 224 is configured to adjust the tension of the first drive rope 30 or the second drive rope 40.

[0046] As can be seen, the pretensioner 224 is rotatably mounted in the first mounting hole. The drive rope passes around the rotating shaft and through the pretensioner groove before connecting to the fixing component. The tension of the drive rope can be easily adjusted by rotating the pretensioner. The adjustment is highly accurate and simple to operate. The pretensioner groove limits the drive rope, preventing the rope from slipping during adjustment, ensuring the stability of tension adjustment, and ensuring that the movement response of the universal finger is always accurate and controllable.

[0047] In one embodiment, a first through hole and a second through hole are provided at the second preset position. Both the first through hole and the second through hole are provided with relief grooves 226. The relief grooves 226 are connected to the first through hole or the second through hole. The relief grooves 226 are configured to avoid the first drive rope 30 or the second drive rope 40. Fasteners are provided in the relief grooves 226. The fasteners are configured to press the end of the variable stiffness sleeve 32 in the first through hole or the second through hole.

[0048] Specifically, the fastener is a screw.

[0049] As can be seen, the first and second through holes at the second preset position of the dexterous hand are used to install the variable stiffness sleeve 32. The clearance groove 226 on the side of the through hole provides a routing space for the drive rope, avoiding friction and wear between the rope and the edge of the through hole. The fastener 225 presses and fixes the end of the sleeve, ensuring that the sleeve is installed firmly and preventing it from loosening during transmission. The compact layout of the clearance groove 226 and the fastener 225 does not occupy extra space.

[0050] A three-degree-of-freedom dexterous hand includes a base 70, a universal finger joint 71, a first finger segment 72, a second finger segment 73, a third finger segment 74, a linkage 75, a first cable-driven joint module 76, a second cable-driven joint module 77, and a third cable-driven module 78. The first end of the first finger segment 72 is mounted on the base 70 via the universal finger joint 71. A first joint 80 is mounted on the base 70. A second joint 81 is mounted on the universal finger joint 71. A third joint 82 is mounted on the first finger segment 72. A fourth joint 83 is mounted on the third finger segment 74. A linkage 75 is provided between the third joint 82 and the fourth joint 83. The first cable-driven module is equipped with... The first joint 80 is configured to rotate in the forward or reverse direction, the second rope-driven joint module 77 is configured to drive the second joint 81 to rotate in the forward or reverse direction, and the third rope-driven joint module 78 is configured to drive the fourth joint 83 to rotate in the forward or reverse direction. The first finger segment 72, the second finger segment 73, and the third finger segment 74 all include the aforementioned general-purpose fingers. The first finger segment 72 is provided with a first angle sensing component 90, a second angle sensing component 91, and a third angle sensing component 92. The first angle sensing component 90, the second angle sensing component 91, and the third angle sensing component 92 are respectively configured to detect the rotation angle of the first joint 80, the second joint 81, and the fourth joint 83.

[0051] Specifically, the first joint 80, the second joint 81, the third joint 82, and the fourth joint 83 correspond to the first finger joint groove wheel, the second finger joint groove wheel, the third finger joint groove wheel, and the fourth finger joint groove wheel, respectively.

[0052] Specifically, the first and second knuckle groove wheels drive the first joint 80 and the second joint 81 respectively, and the two are orthogonally arranged at the general finger joint 71.

[0053] Specifically, the first knuckle groove wheel is fixed to the universal finger joint 71, and the second knuckle groove wheel is integrated with the first finger segment 72. No knuckle groove wheel is provided on the second finger segment 73, while the third finger segment 74 is equipped with a third knuckle groove wheel. This wheel enables proportional linkage between the third joint 82 and the fourth joint 83 via a linkage rod 75.

[0054] As can be seen, this three-degree-of-freedom dexterous hand integrates three sets of rope-driven joint modules, which drive the first joint 80, the second joint 81, and the fourth joint 83 to rotate respectively. Together with the universal finger joint 75 and the linkage 71, it realizes flexible multi-degree-of-freedom movement of the fingers, while saving space and having a compact structure. The three sets of angle sensing components on the first finger segment 72 detect the rotation angle of the corresponding joints, forming a multi-joint closed-loop control to ensure the coordination and accuracy of the movement of each joint. This design effectively avoids the motion interference of the transmission rope 31 between the joints at the mechanical structure level, realizes the decoupling of motion and force, eliminates the dependence on complex decoupling algorithms, and improves the accuracy and operating efficiency of the control algorithm.

[0055] The above embodiments merely illustrate the basic principles and characteristics of the present invention. The present invention is not limited to the above examples. Various changes and modifications can be made to the present invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A universal finger for a rope-driven dexterous hand, characterized in that, The universal finger includes finger segments, a chord-driven joint module, and an angle sensor, wherein: The rope-driven joint module includes a base, a drive assembly, a first drive rope, a second drive rope, and a rotatable joint. One end of the finger segment is provided with the joint. The first end of the first drive rope and the first end of the second drive rope are respectively connected to the drive assembly, and the second end of the first drive rope and the second drive rope are respectively connected to the joint. The drive assembly is disposed on the base and is configured to drive the first drive rope and the second drive rope to move in opposite directions simultaneously, so as to drive the joint to rotate in the forward or reverse direction, thereby driving the finger segment to rotate. The angle sensing component is disposed on the joint and is configured to detect the rotation angle of the joint. Both the first drive rope and the second drive rope include a transmission rope and a flexible variable stiffness sleeve. The transmission rope passes through the inner hole of the variable stiffness sleeve, and both the first end and the second end of the transmission rope extend out of the variable stiffness sleeve. The variable stiffness sleeve is configured to limit and support the transmission rope. The first end of the transmission rope is detachably connected to the drive end of the drive assembly, and the second end of the transmission rope is detachably connected to the joint. The first end of the variable stiffness sleeve is provided with a first connecting part, and the second end of the variable stiffness sleeve is provided with a second connecting part. The first connecting part is detachably connected to the first preset position of the dexterous hand, and the second connecting part is detachably connected to the second preset position of the dexterous hand.

2. The universal finger for a rope-driven dexterous hand according to claim 1, characterized in that, The angle sensing assembly includes an angle sensor and a drive belt. The angle sensor is connected to the joint via the drive belt and is configured to detect the rotation angle of the joint.

3. The universal finger for a rope-driven dexterous hand according to claim 1, characterized in that, The variable stiffness sleeve is made by tightly winding a single flat or round steel wire into a spiral tube.

4. The universal finger for a rope-driven dexterous hand according to claim 1, characterized in that, The variable stiffness sleeve includes a high stiffness section and a low stiffness section. The high stiffness section is configured to form the planned path of the transmission rope, and the low stiffness section is configured to bend or straighten together with the transmission rope. The outer diameter of the high stiffness section is larger than the outer diameter of the low stiffness section, and the low stiffness section is a flexible body.

5. The universal finger for a rope-driven dexterous hand according to claim 1, characterized in that, The drive assembly includes a drive member and a transmission assembly. The drive member is disposed at the bottom of the base, and the transmission assembly is disposed inside the base. The transmission assembly includes a rotating shaft, a first guide member, and a second guide member. The rotating shaft is rotatably disposed on the base. The first guide member and the second guide member are respectively disposed on both sides of the rotating shaft. The first end of the first drive rope is wound around the first end of the rotating shaft, and the first end of the second drive rope is wound around the second end of the rotating shaft. The winding directions of the first end of the first drive rope and the first end of the second drive rope are opposite. The second end of the first drive rope is connected to the first fixing part of the joint via the first guide member, and the second end of the second drive rope is connected to the second fixing part of the joint via the second guide member. The drive end of the drive member is connected to one end of the rotating shaft. The drive member is configured to drive the rotating shaft to rotate forward or backward along its own axis, thereby driving the first drive rope and the second drive rope to tighten or loosen, and thus driving the joint to rotate forward or backward.

6. The universal finger for a rope-driven dexterous hand according to claim 1, characterized in that, The rotating shaft is provided with guide parts at both ends, and guide slopes are provided on both sides of the guide parts.

7. The universal finger for a rope-driven dexterous hand according to claim 1, characterized in that, The guide portion has a first mounting hole, a pre-tensioning member is provided in the first mounting hole, the pre-tensioning member has a second mounting hole, a fixing member is provided in the second mounting hole, and the fixing member is configured to fix the first end of the first drive rope or the first end of the second drive rope.

8. The universal finger for a rope-driven dexterous hand according to claim 1, characterized in that, The pretensioner is rotatably disposed in the first mounting hole. The pretensioner has a pretensioning groove. The first end of the first drive rope or the first end of the second drive rope passes around the rotating shaft and through the pretensioning groove to be fixedly connected to the fixing member. The pretensioner is configured to adjust the tension of the first drive rope or the second drive rope.

9. The universal finger for a rope-driven dexterous hand according to claim 1, characterized in that, A first through hole and a second through hole are provided at the second preset position. Both the first through hole and the second through hole are provided with clearance grooves on their sides. The clearance grooves are connected to the first through hole or the second through hole. The clearance grooves are configured to allow clearance from the first drive rope or the second drive rope. Fasteners are provided in the clearance grooves. The fasteners are configured to press the end of the variable stiffness sleeve in the first through hole or the second through hole.

10. A three-degree-of-freedom dexterous hand finger, characterized in that, The three-degree-of-freedom dexterous hand fingers include a base, a universal finger joint, a first finger segment, a second finger segment, a third finger segment, a linkage, a first cable-driven joint module, a second cable-driven joint module, and a third cable-driven module, wherein: The first end of the first finger segment is disposed on the base via a universal finger joint. A first joint is disposed on the base, a second joint is disposed on the universal finger joint, a third joint is disposed on the first finger segment, a fourth joint is disposed on the third finger segment, and a linkage is disposed between the third joint and the fourth joint. The first rope drive module is configured to drive the first joint to rotate forward or backward, the second rope drive module is configured to drive the second joint to rotate forward or backward, and the third rope drive module is configured to drive the fourth joint to rotate forward or backward. The first finger segment, the second finger segment, and the third finger segment all include the universal finger described in any one of claims 1-9. The first finger segment is provided with a first angle sensing component, a second angle sensing component and a third angle sensing component, which are respectively configured to detect the rotation angle of the first joint, the second joint and the fourth joint.

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