Knuckle, finger, dexterous hand and robot

Abstract

The invention provides a knuckle, a finger, a dexterous hand and a robot, and relates to the field of robotics.The knuckle comprises a bottom wall, a top wall and a side wall, the side wall is connected with the bottom wall and the top wall, a wiring channel is formed in the top wall and penetrates through the two opposite ends of the top wall, and two rows of guide columns are arranged in the wiring channel; a limiting gap for a tendon rope to penetrate through is formed between the two rows of guide columns, and receding notches used for receding the tendon rope are formed in the two opposite ends of the top wall.

Description

Technical Field

[0001] This application relates to the field of robotics, and more specifically, to a knuckle, finger, dexterous hand, and robot. Background Technology

[0002] Currently, dexterous hands are an important component of robots, especially humanoid robots, used to perform various actions such as grasping and holding. Current dexterous hands include tethered dexterous hands and linkage-based dexterous hands. Tethered dexterous hands are characterized by their lightweight and simple structure. The fingers of a tethered dexterous hand are composed of multiple sequentially hinged phalanges. Their working mechanism involves a motor driving a winch wound with tendon ropes to rotate, thereby pulling the tendon ropes and forcing the phalanges to rotate relative to each other, causing the fingers to bend. When the motor drives the winch wound with tendon ropes to rotate in the opposite direction, the phalanges can automatically return to a straight state under the action of an elastic reset component. Generally, the straightened state is considered the initial state of the finger.

[0003] However, during the repeated bending and straightening of the fingers in current rope-driven dexterous hands, slight delays in grasping movements often occur, resulting in less smooth grasping actions. Sometimes, even tendon rope breakage can lead to sudden failure of the finger's gripping function. This is especially problematic when the fingers are holding objects, as the sudden failure of the gripping function can cause the object to slip off the dexterous hand. Therefore, current technology generally requires replacing the tendon rope after a period of use to avoid these problems. However, due to the extremely compact structure of dexterous hand fingers, tendon rope replacement is time-consuming and laborious, which is detrimental to the use and promotion of robots. Summary of the Invention

[0004] I have found that the current lack of smoothness in finger grasping movements is due to the unrestrained movement of the chordae tendons during stretching and releasing, especially during frequent and abrupt transitions between these movements. This excessive movement significantly contributes to the slight delay and lack of smoothness in dexterity-related grasping actions. Furthermore, I have discovered that a major contributing factor to chordae tendon rupture is that each time a finger bends, the relative rotation of adjacent phalanges causes the sharp edges of the phalanges to frequently rub against the chordae tendons. With repeated repetitions, this wear and tear on the chordae tendons worsens, eventually leading to sudden breakage.

[0005] To address this issue, this application proposes a finger joint structure to resolve the problems of insufficient smoothness in grasping movements and tendon ligament wear and breakage in dexterous hands.

[0006] In a first aspect, embodiments of this application provide a knuckle, which includes a bottom wall, a top wall, and a side wall, wherein the side wall connects the bottom wall and the top wall; A wiring channel is formed inside the top wall, the wiring channel runs through the opposite ends of the top wall, and two rows of guide posts are provided in the wiring channel, with a limiting gap formed between the two rows of guide posts for the tendon rope to pass through. The top wall has clearance notches at opposite ends to allow the tendon ligament to pass.

[0007] In a second aspect, embodiments of this application provide a finger, including the aforementioned knuckles.

[0008] In a third aspect, embodiments of this application provide a dexterous hand, including the fingers described above.

[0009] In a fourth aspect, embodiments of this application provide a robot including the dexterous hand described above. Attached Figure Description

[0010] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 A schematic diagram of the external structure of a finger (index finger) provided in an embodiment of this application; Figure 2 for Figure 1 A first-angle sectional view of the middle finger; Figure 3 for Figure 1 A second-angle sectional view of the middle finger; Figure 4 for Figure 1 A structural diagram of the middle finger after removing each phalanx; Figure 5 for Figure 1 A schematic diagram of the external structure of the first joint (base segment) of the middle finger; Figure 6 for Figure 5 A schematic diagram of the external structure of the middle phalanx (base segment) from another angle; Figure 7 for Figure 6 A sectional view of the middle phalanx (root segment) (with the first bottom wall removed); Figure 8 for Figure 1 A diagram illustrating the state of the middle finger after it has been bent.

[0012] Icons: 100 - Index finger; 1 - Finger root segment; 11 - First bottom wall; 12 - First side wall; 13 - First top wall; 101 - First clearance gap; 131 - First wiring channel; 1311 - First limiting gap; 132A - Upper row guide post; 132B - Lower row guide post; 1310 - First enclosure wall; 2 - Middle segment; 21 - Second bottom wall; 22 - Second side wall; 23 - Second top wall; 201 - Second clearance gap; 231 - Second wiring channel; 2311 - Second limiting gap; 232A - Upper row guide post; 232B - Lower row guide post; 2310 - Second enclosure wall; 3 - Fingertip section; 31- Third bottom wall; 32- Third side wall; 33- Third top wall; 301- Third clearance notch; 331- Third wiring channel; 3311- Third limiting gap; 332A- Upper guide post; 332B- Lower guide post; 332C- Hanging platform; 3310- Third enclosure wall; 4- Mounting platform; 41- Wire hole; 42A- Upper guide post; 42B- Lower guide post; 43- Fourth limiting gap; 5- Palm part; 61- First pin; 62- Second pin; 63- Third pin; 71- First torsion spring; 72- Second torsion spring; 73- Third torsion spring; 8- Tendon rope. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0014] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0015] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0016] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. 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, and therefore should not be construed as a limitation on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0017] Furthermore, terms such as "horizontal" and "vertical" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," not that the structure must be completely horizontal, but can be slightly tilted.

[0018] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0019] This embodiment provides a finger structure suitable for dexterous hands, which are suitable for robots, especially humanoid robots.

[0020] This finger structure can be applied to any one of the thumb, index finger, middle finger, ring finger, and little finger. Of course, if a dexterous hand has fewer or more than five fingers, this finger structure can still be applied to all fingers.

[0021] For ease of description, please refer to the reference. Figures 1 to 8 The following explanation uses the index finger as an example, which is 100.

[0022] The index finger 100 generally includes three segments: the root segment 1 near the palm 5 of the robot, the tip segment 3 away from the palm 5, and the middle segment 2 located between the root segment 1 and the tip segment 3. The two ends of the middle segment 2 can be hinged to the tip segment 3 and the root segment 1 via the first pin 61 and the second pin 62, respectively.

[0023] In this embodiment, the finger root segment 1 is not directly connected to the palm portion 5, but is hinged to a mounting platform 4. For example, the finger root segment 1 can be hinged to the mounting platform 4 via a third pin 63, and the mounting platform 4 can be fixed to the palm portion 5 via screws. In other embodiments, the mounting platform 4 can be integrally formed with the palm portion 5, so that the mounting platform 4 is part of the palm portion 5. The mounting platform 4 is configured to enable the finger root segment 1 to rotate relative to the palm portion 5, thereby realizing the index finger 100 in a closed state facing the palm portion 5 and an extended state away from the palm portion 5. Although the finger root segment 1 can also be directly hinged to the palm portion 5, by adding the mounting platform 4, it is more convenient to open the hinge hole on the mounting platform 4 than to directly open the hinge hole on the palm portion 5 for the finger root segment 1 to be hinged.

[0024] In addition, a wire hole 41 can be formed on the mounting platform 4 for the tendon cord 8 to pass through. The tendon cord is a basic component of the rope-driven dexterous hand, and the installation method of the tendon cord 8 will be described in detail later.

[0025] A first torsion spring 71 and a second torsion spring 72 are respectively fitted onto the first pin 61 and the second pin 62. The two torsion arms of the first torsion spring 71 elastically abut against the fingertip segment 3 and the middle segment 2, respectively. The two torsion arms of the second torsion spring 72 elastically abut against the finger root segment 1 and the middle segment 2, respectively. In order to enable the index finger 100 to rotate relative to the palm part 5 as a whole, a third torsion spring 73 is also fitted onto the third pin 63. The two torsion arms of the third torsion spring 73 elastically abut against the finger root segment 1 and the mounting platform 4, respectively.

[0026] The function of the first torsion spring 71, the second torsion spring 72, and the third torsion spring 73 in this embodiment is as follows: When the index finger 100 is bent relative to the mounting platform 4 and the palm 5 and is in a folded state, the fingertip segment 3 rotates around the first pin 61 relative to the middle segment 2, which will cause the first torsion spring 71 to be compressed and accumulate elastic potential energy. Then, the middle segment 2 rotates around the second pin 62 relative to the finger root segment 1, which will cause the second torsion spring 72 to be compressed and accumulate elastic potential energy. Then, the finger root segment 1 rotates around the third pin 63 relative to the mounting platform 4, which will cause the third torsion spring 73 to be compressed and accumulate elastic potential energy. The elastic potential energy accumulated by the first torsion spring 71, the second torsion spring 72, and the third torsion spring 73 provides a reset driving force for each finger segment (fingert segment 3, middle segment 2, and finger root segment 1) to return to the initial state (the straightened state of the index finger 100).

[0027] In this embodiment, the root segment 1, middle segment 2, and fingertip segment 3 each include an outer shell and a hollow cavity formed within the outer shell. Each outer shell has a routing channel that runs through both ends of each finger segment, through which the tendon cord 8 passes. Specifically, in this embodiment, the root segment 1, middle segment 2, and fingertip segment 3 are all finger joints, and their general structures are the same. All three are hollow cavity structures formed by a bottom wall, a top wall, and two oppositely arranged side walls.

[0028] The finger root segment 1 includes: a first bottom wall 11, a first top wall 13, and two opposing first side walls 12, the first side walls 12 connecting the first bottom wall 11 and the first top wall 13; a first wiring channel 131 is formed in the first top wall 13, which runs through both ends of the first top wall 13. Specifically, the first top wall 13 may include two parallel first enclosure walls 1310 extending toward the first bottom wall 11, and the first wiring channel 131 is formed between the two first enclosure walls 1310. Two rows of guide posts are provided along the extension direction of the first wiring channel 131, namely, upper row guide posts 132A and lower row guide posts 132B. The number of guide posts in the upper row 132A is unlimited, and the number of guide posts in the lower row 132B is kept the same as the number of guide posts in the upper row 132A. In the finger root segment 1, there are two guide posts in both the upper row 132A and the lower row 132B. The upper row guide posts 132A and the lower row guide posts 132B not only penetrate the first side wall 12, but also penetrate the two first enclosure walls 1 that are side by side. 310, so that the upper row of guide posts 132A and the lower row of guide posts 132B are inserted into the two parallel first enclosure walls 1310, and a first limiting gap 1311 is formed between the upper row of guide posts 132A and the lower row of guide posts 132B for the tendon cord 8 to pass through. In this way, the two parallel first enclosure walls 1310 and the first limiting gap 1311 together enclose a "closed wire channel" for the tendon cord 8 to pass through, which can stably restrain the tendon cord 8. In addition, the first top wall 13 has a first clearance notch 101 at both ends to avoid the tendon cord 8.

[0029] In addition, the upper guide post 132A and the lower guide post 132B can be pins installed in the first wiring channel 131. In order to reduce the wear of the pins on the tendon cord 8, the pins can be rotatably installed in the first wiring channel 131 so that the tendon cord 8 is in contact with the pins by rotational friction.

[0030] The middle segment 2 includes: a second bottom wall 21, a second top wall 23, and two opposing second side walls 22, the second side walls 22 connecting the second bottom wall 21 and the second top wall 23; a second wiring channel 231 is formed in the second top wall 23, which runs through both ends of the second top wall 23. Specifically, the second top wall 23 may include two parallel second enclosure walls 2310 extending toward the second bottom wall 21, and the two enclosure walls 2310 together form the second wiring channel 231. Two rows of guide posts are provided along the extension direction of the second wiring channel 231, namely, upper row guide posts 232A and lower row guide posts 232B. The number of guide posts in the upper row 232A is unlimited, while the number of guide posts in the lower row 232B is kept the same as the number of guide posts in the upper row 232A. In the middle segment 2, there are two guide posts in both the upper row 232A and the lower row 232B. The upper row guide posts 232A and the lower row guide posts 232B not only penetrate the second side wall 22, but also penetrate the two parallel second enclosure walls 2. 310, so that the upper row of guide posts 232A and the lower row of guide posts 232B are inserted into the two parallel second enclosure walls 2310, and a second limiting gap 2311 is formed between the upper row of guide posts 232A and the lower row of guide posts 232B for the tendon cord 8 to pass through. In this way, the two parallel second enclosure walls 2310 and the second limiting gap 2311 together enclose a "closed wire channel" for the tendon cord 8 to pass through, which can stably restrain the tendon cord 8. In addition, the first and last ends of the second top wall 23 are formed with second clearance notches 201 for avoiding the tendon cord 8.

[0031] In addition, the upper guide post 232A and the lower guide post 232B can be pins installed in the second wiring channel 231. In order to reduce the wear of the pins on the tendon rope 8, the pins can be rotatably installed in the second wiring channel 231 so that the tendon rope 8 contacts the pins with rotational friction.

[0032] The fingertip segment 3 includes: a third bottom wall 31, a third top wall 33, and two opposing third side walls 32, the third side walls 32 connecting the third bottom wall 31 and the third top wall 33; a third wiring channel 331 is formed in the third top wall 33, which runs through both ends of the third top wall 33. Specifically, the third top wall 33 may include two parallel third enclosure walls 3310 extending toward the third bottom wall 31, and the third wiring channel 331 is formed between the two third enclosure walls 3310. Two rows of guide posts are provided along the extension direction of the third wiring channel 331, namely the upper row of guide posts 332A and the lower row of guide posts 332B. The number of guide posts in the upper row of guide posts 332A is unlimited, while the number of guide posts in the lower row of guide posts 332B is kept the same as the number of guide posts in the upper row of guide posts 332A. In the fingertip segment 3, the number of guide posts in the upper row of guide posts 332A and the number of guide posts in the lower row of guide posts 332B are both one. The upper row of guide posts 332A and the lower row of guide posts 332B not only penetrate the third side wall 32, but also penetrate the two parallel third enclosure walls 3. 310, so that the upper row of guide posts 332A and the lower row of guide posts 332B pass through the two parallel third enclosure walls 3310, and a third limiting gap 3311 is formed between the upper row of guide posts 332A and the lower row of guide posts 332B for the tendon cord 8 to pass through. In this way, the two parallel third enclosure walls 3310 and the third limiting gap 3311 together enclose a "closed wire channel" for the tendon cord 8 to pass through, which can stably restrain the tendon cord 8. In addition, the first and last ends of the third top wall 33 are formed with a third clearance notch 301 for avoiding the tendon cord 8.

[0033] In addition, the upper guide post 332A and the lower guide post 332B can be pins installed in the third wiring channel 331. In order to reduce the wear of the pins on the tendon cord 8, the pins can be rotatably installed in the third wiring channel 331 so that the tendon cord 8 contacts the pins with rotational friction.

[0034] like Figure 4One end of the tendon cord 8 passes sequentially through the wire hole 41, the first limiting gap 1311, the second limiting gap 2311, and the third limiting gap 3311 and is fixed to the fingertip segment 3. Specifically, it can be attached to a mounting platform 332C located within the third wiring channel 331. The mounting platform 332C can be, for example, a fixing pin extending within the third wiring channel 331, which can pass through the third side wall 32 into the third wiring channel 331. The other end of the tendon cord 8 is connected to a drive module located on the palm portion 5. The drive module pulls the tendon cord 8. The drive module may include a motor and a winch driven by the motor, and the tendon cord 8 is wound around the winch. To improve the guiding and limiting effect of the tendon cord 8, the other end of the tendon cord 8 specifically passes through the wire hole 41 of the mounting platform 4 and is connected to the winch. To further reduce wear on the tendon cord 8, a pair of guide posts can be provided inside the wire hole 41. The pair of guide posts includes an upper guide post 42A and a lower guide post 42B. The upper guide post 42A and the lower guide post 42B can be pins installed inside the wire hole 41. To reduce wear on the tendon cord 8 caused by the pins, the upper guide post 42A and the lower guide post 42B can be rotatably installed inside the wire hole 41. The upper guide post 42A and the lower guide post 42B essentially form a fourth limiting gap 43 through which the tendon cord 8 passes. More specifically, the other end of the tendon cord 8 passes through the fourth limiting gap 43 and is connected to the winch. In this way, when the tendon cord 8 contacts the upper guide post 42A and the lower guide post 42B, it is rotational friction.

[0035] As described above, when the tendon rope 8 is pulled by the winch driven by the motor, it causes the index finger 100 to bend relative to the mounting platform 4 and the palm 5, thus forming a folded state (e.g. Figure 8 The folded state is also the posture of the index finger 100 when performing a gripping action. In each phalanx, since the first top wall 13 of the root segment 1 has a first clearance notch 101 at both ends, the second top wall 23 of the middle segment 2 has a second clearance notch 201 at both ends, and the third top wall 33 of the fingertip segment 3 has a third clearance notch 301 at both ends, as the index finger 100 bends further, the tendon cord 8 can be partially stored in the first clearance notch 101, the second clearance notch 201, or the third clearance notch 301. This prevents the tendon cord 8 from directly scraping against the corners of the root segment 1, the middle segment 2, and the fingertip segment 3, thereby avoiding the "cutting line problem" of each phalanx on the tendon cord. This can effectively ensure the working reliability of the index finger 100 when it is bent and in the folded state.

[0036] Furthermore, when the tendon rope 8 is bent and folded in place by the index finger 100, the upper and lower guide posts within each phalanx restrict the vertical movement of the tendon rope 8, and the two parallel enclosures restrict its horizontal movement. This ensures that the tendon rope 8 is always firmly contained within the first limiting gap 1311, the second limiting gap 2311, and the third limiting gap 3311, effectively reducing the shaking of the tendon rope 8 during operation. This makes the winch winding process of the tendon rope 8 smoother and more stable, facilitating a smooth grasping action and mitigating, to some extent, the slight delay in the grasping action of a dexterous hand. Additionally, making the edges of each enclosure and the edges of each clearance notch rounded can also help avoid the aforementioned "cutting line problem" to some extent.

[0037] Under the reset driving action of the first torsion spring 71, the second torsion spring 72, and the third torsion spring 73, the tendon cord 8 is always firmly confined within the first limiting gap 1311, the second limiting gap 2311, and the third limiting gap 3311 during the process of the index finger 100 re-stretching to a straight posture. The tendon cord 8 gradually resets from a state of being partially contained within the first yielding gap 101, the second yielding gap 201, or the third yielding gap 301 to the initial straight state. During the process of the index finger 100 going from the initial straight state to a bent and contracted state, and then back to the initial straight state, the tendon cord 8 is always firmly confined within the first limiting gap 1311, the second limiting gap 2311, and the third limiting gap 3311. Moreover, the tendon cord 8 can always be at least partially contained within the first yielding gap 101, the second yielding gap 201, or the third yielding gap 301 to avoid the aforementioned "cutting line problem".

[0038] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A finger joint, characterized in that, It includes a bottom wall, a top wall, and side walls, wherein the side walls connect the bottom wall and the top wall; A wiring channel is formed inside the top wall, the wiring channel runs through the opposite ends of the top wall, and two rows of guide posts are provided in the wiring channel, with a limiting gap formed between the two rows of guide posts for the tendon rope to pass through. The top wall has clearance notches at opposite ends to allow the tendon ligament to pass.

2. The knuckle according to claim 1, characterized in that, Each of the guide posts is rotatable.

3. The knuckle according to claim 1, characterized in that, The top wall includes two enclosures extending toward the bottom wall, and the two enclosures form the wiring channel.

4. The knuckle according to claim 3, characterized in that, The two enclosure walls are arranged side by side.

5. The knuckle according to claim 3, characterized in that, Each of the guide posts penetrates the two enclosure walls.

6. The knuckle according to claim 3, characterized in that, The edges of each of the aforementioned enclosures have a rounded structure.

7. The knuckle according to claim 1, characterized in that, The edges of each of the aforementioned clearance notches have a rounded structure.

8. A finger, characterized in that, Including the knuckles as described in any one of claims 1-7.

9. A dexterous hand, characterized in that, Including the fingers as described in claim 8.

10. A robot, characterized in that, Including the dexterous hand as described in claim 9.

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