Ankle device and robot

Abstract

The utility model relates to robot technical field provides an ankle device and robot, include: first support, second support and drive assembly, first support is used for installing robot sole structure, first support is provided with first connecting rod on rotation, second support is used for supporting first support, first connecting rod is provided with second connecting rod, and second connecting rod is perpendicular with first connecting rod, second support is rotatably connected with second connecting rod, drive assembly includes first drive mechanism and second drive mechanism, first drive mechanism is used for driving first support to rotate around first connecting rod, second drive mechanism is used for driving first support to rotate around second connecting rod, the utility model drives first support to do side swing around first connecting rod through first drive mechanism, drives first support to do pitch around second connecting rod by second drive mechanism, makes sole structure have two mutually perpendicular, each other decoupling rotation freedom of degree with pitch of side swing relative shank.

Description

Technical Field

[0001] This utility model relates to the field of robotics, and in particular to an ankle device and a robot. Background Technology

[0002] When robots walk, run, climb stairs, and navigate complex terrain, their feet need to rotate in both pitch and lateral directions using their ankles to maintain ground contact, balance, and efficient walking. The ankle mechanism, as a core component connecting the robot's lower leg and foot, directly affects the robot's motion performance, stability, and energy consumption. Existing robot foot actuators mostly employ parallel transmission designs, with each degree of freedom driven by an independent motor and reducer. Multiple links are sequentially hinged, and the power is arranged in series along the limb axis, achieving the two rotational degrees of freedom of the foot through multi-branch collaboration. However, this parallel structure suffers from strong motion coupling; even a small rotation in any degree of freedom simultaneously triggers nonlinear changes in the length and hinge angle of multiple links. Inverse kinematics calculations are complex, requiring high computing power for real-time calculations, resulting in high main control hardware costs and poor real-time performance. Furthermore, rigid links have minimum limit displacements, restricting the foot's pitch and lateral angles, making it difficult to achieve extreme gaits such as full squats and traversing low stairs. Insufficient clearance between the links can also lead to mechanical interference during large foot swings, posing a risk of jamming or even link breakage. Furthermore, rigid linkage assembly requires pre-tightening tolerances. During small swings, the prestress between the links cancels each other out, causing transmission lag. The rope-driven parallel scheme also suffers from low-frequency vibrations at the foot due to rope creep and elongation after repeated reciprocating motions, requiring periodic tension calibration. Moreover, wear on any link pin or slack in the parallel structure can disrupt the closed-loop force balance, leading to unbalanced forces on the foot and momentary instability of the robot, which is difficult to remedy through algorithms. In addition, the parallel structure contains multiple ball joints, each with sliding friction, resulting in rapid grease wear, short maintenance cycles, and a significant increase in maintenance time. Utility Model Content

[0003] The purpose of this invention is to provide an ankle device and robot that can solve or at least alleviate one or more of the aforementioned problems and other issues existing in the prior art.

[0004] To achieve the aforementioned objective, the first aspect of this utility model provides an ankle device for use in a robot, comprising: a first support for mounting the robot's foot structure, and a first connecting rod rotatably disposed on the first support; A second support is used to support the first support. A second connecting rod is provided on the first connecting rod, and the second connecting rod is perpendicular to the first connecting rod. The second support is rotatably connected to the second connecting rod. A drive assembly, comprising a first drive mechanism and a second drive mechanism; the first drive mechanism is used to drive the first support to rotate about the first connecting rod; the second drive mechanism is used to drive the first support to rotate about the second connecting rod. The second connecting rod is provided with an adjustment slot, and a third connecting rod is disposed in the adjustment slot; the second driving mechanism includes a transmission rod, and the transmission rod is provided with a plurality of adjustment holes along its length direction, and the third connecting rod is rotatably connected to the transmission rod through the adjustment holes.

[0005] In the ankle device described above, optionally, the first support is U-shaped, the first support includes a first horizontal plate and a first vertical plate and a second vertical plate disposed on both sides of the first horizontal plate, and the foot structure is disposed at the bottom of the first horizontal plate.

[0006] In the ankle device described above, optionally, the first drive mechanism includes a first motor, the housing of the first motor is connected to the first vertical plate, the output end of the first motor is connected to the first end of the first connecting rod, and the second end of the first connecting rod is rotatably connected to the second vertical plate.

[0007] In the ankle device described above, optionally, the second support is U-shaped, and the second support includes a second horizontal plate and a third vertical plate and a fourth vertical plate disposed on both sides of the second horizontal plate, and the second connecting rod is disposed between the third vertical plate and the fourth vertical plate.

[0008] In the ankle device described above, optionally, the first connecting rod is provided with a pivot hole, and the second connecting rod passes through the pivot hole.

[0009] In the ankle device described above, the second drive mechanism may optionally include a second motor and a rotating arm, the output end of the second motor being connected to the rotating arm, the rotating arm being provided with a hinge shaft, and the transmission rod being rotatably connected to the hinge shaft.

[0010] Optionally, the ankle device described above may also include a linkage rod, the bottom of which is connected to the second horizontal plate, and the second motor is provided on the side wall of the linkage rod.

[0011] Optionally, in the ankle device as described above, the second horizontal plate is provided with a clearance groove.

[0012] In the ankle device described above, optionally, an elastic buffer is provided between the first support and the foot structure.

[0013] According to another aspect of the present invention, a robot is also provided, including a body and an ankle device as described in any of the preceding claims, the ankle device being mounted on the body.

[0014] Compared with existing technologies, the advantages of this invention are as follows: A cross-axis structure is formed by two mutually perpendicular connecting rods, a first driving mechanism and a second driving mechanism. The first support is driven to laterally swing around the first connecting rod, and the first support is driven to pitch around the second connecting rod by a second driving mechanism. This gives the foot structure two mutually perpendicular and decoupled rotational degrees of freedom relative to the lower leg: lateral swing and pitch. Compared with multi-branch parallel structures, this device has a simpler transmission path, fewer friction pairs, and avoids problems such as complex inverse kinematics calculations, assembly delays, and single-point failures caused by motion coupling, significantly improving reliability and maintainability. The first and second motors independently drive two degrees of freedom, eliminating the need for additional decoupling algorithms, thus simplifying the control system and reducing development and maintenance costs. The second motor is positioned above the second horizontal plate via a linkage rod, keeping the mass of the driving component away from the foot end, reducing end mass, improving mass distribution, decreasing rotational inertia, and enhancing dynamic response speed. Multiple adjustment through holes along the length of the transmission rod, in conjunction with adjustment slots on the second connecting rod, allow adjustment of the transmission ratio and pitch stroke by changing the insertion position of the third connecting rod. This enables the same drive assembly to adapt to different pace states or loads without replacing any parts. The elastic buffer between the first support and the foot structure absorbs landing impact and improves walking stability, while the clearance slots on the second horizontal plate provide clearance for moving parts. The overall structure is compact, reliable, and easy to maintain. Attached Figure Description

[0015] Figure 1 This is a front view of the ankle device of this utility model; Figure 2 This is a first-view perspective perspective view of the ankle device of this utility model; Figure 3 This is a second-view perspective perspective view of the ankle device of this utility model; Figure 4 This is a schematic diagram of the structure of the first connecting rod in the ankle device of this utility model.

[0016] In the diagram: 1. First horizontal plate; 2. First vertical plate; 3. Second vertical plate; 4. Second horizontal plate; 5. Third vertical plate; 6. Fourth vertical plate; 7. First connecting rod; 8. Second connecting rod; 9. First motor; 10. Second motor; 11. Rotary arm; 12. Hinge shaft; 13. Transmission rod; 14. Adjustment through hole; 15. Linkage rod; 16. Foot structure; 17. Elastic buffer; 18. Third connecting rod. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] It should be noted that in the description of this utility model, the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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. The terms "first," "second," and similar words used in the description of this utility model do not indicate any order, quantity, or importance, but are only used to distinguish different components, and therefore should not be construed as limiting this utility model.

[0019] Furthermore, it should be understood that, for ease of description, the dimensions of the various components shown in the accompanying drawings are not drawn to actual scale; for example, the thickness or width of some layers may be exaggerated relative to other layers.

[0020] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined or described in one figure, it will not need to be discussed or described in detail in the description of the subsequent figures.

[0021] See Figures 1 to 4 According to one aspect of this utility model, an ankle device is provided for use in a robot, comprising: a first support, a second support, and a drive assembly. The drive assembly includes a first drive mechanism and a second drive mechanism, which are respectively used to drive the first support to rotate in two degrees of freedom.

[0022] The first support is used to mount the robot's foot structure 16. The bottom of the foot structure 16 is equipped with an anti-slip and wear-resistant pad to increase friction with the ground and prevent slipping during walking. In this embodiment, the first support is U-shaped, including a first horizontal plate 1 and a first vertical plate 2 and a second vertical plate 3 disposed on both sides of the first horizontal plate 1. The foot structure 16 is mounted on the bottom of the first horizontal plate 1 and can be fixed to the bottom of the first horizontal plate 1 by gluing, snap-fitting, or other methods. Furthermore, an elastic buffer 17 is provided between the first support and the foot structure 16 to buffer the impact and absorb vibration when the foot structure 16 lands; the elastic buffer 17 can be an elastic pad or a rubber block.

[0023] A first connecting rod 7 is rotatably arranged between the first vertical plate 2 and the second vertical plate 3. The first driving mechanism includes a first motor 9. The housing of the first motor 9 is connected to the first vertical plate 2. The output end of the first motor 9 is connected to the first end of the first connecting rod 7. The second end of the first connecting rod 7 is rotatably connected to the second vertical plate 3.

[0024] In this embodiment, the second support is U-shaped and includes a second horizontal plate 4 and a third vertical plate 5 and a fourth vertical plate 6 disposed on both sides of the second horizontal plate 4. The second support is used to support the first support. A second connecting rod 8 is rotatably connected between the third vertical plate 5 and the fourth vertical plate 6. A pivot hole is provided on the first connecting rod 7, and the second connecting rod 8 passes through the pivot hole. The second connecting rod 8 and the first connecting rod 7 are perpendicular to each other, forming a cross-axis structure. The two ends of the second connecting rod 8 are rotatably connected to the third vertical plate 5 and the fourth vertical plate 6 respectively, so that the first support can rotate around the axis of the second connecting rod 8.

[0025] The second drive mechanism includes a second motor 10, a rotating arm 11, and a transmission rod 13. The ankle device in this embodiment also includes a linkage rod 15. The second motor 10 is disposed on the side wall of the linkage rod 15, and the bottom of the linkage rod 15 is connected to the second horizontal plate 4. The output end of the second motor 10 is connected to the rotating arm 11, and a hinge shaft 12 is provided on the rotating arm 11. One end of the transmission rod 13 is rotatably connected to the hinge shaft 12. An adjustment through hole 14 is provided on the transmission rod 13, and an adjustment through groove is provided on the second connecting rod 8. The third connecting rod 18 is both embedded in the adjustment through groove of the second connecting rod 8 and passes through the adjustment through hole 14 of the transmission rod 13, thereby realizing a rotatable connection between the transmission rod 13 and the second connecting rod 8.

[0026] In this embodiment, the rotating arm 11 has a crank-shaped structure. One end of the rotating arm 11 is fixedly connected to the output end of the second motor 10, and the rotating arm 11 rotates synchronously with the output end. The other end is eccentrically provided with a hinge shaft 12, and one end of the transmission rod 13 is rotatably connected to the rotating arm 11 through the hinge shaft 12. When the second motor 10 rotates, the rotating arm 11 drives the hinge shaft 12 to rotate around the output end, thereby pulling the transmission rod 13 to reciprocate, converting the rotational motion of the second motor 10 into the reciprocating motion of the transmission rod 13.

[0027] In addition, multiple adjustment through holes 14 are provided along the length of the transmission rod 13. Since the multiple adjustment through holes 14 are distributed at different positions along the length of the transmission rod 13, the position of the adjustment through hole 14 through which the third connecting rod 18 passes is different. The distance between the adjustment through hole 14, which serves as the connection point between the transmission rod 13 and the second connecting rod 8, and the hinge shaft 12 of the relative rotating arm 11, is also different. By selecting adjustment through holes 14 at different positions, the effective working length and lever ratio of the transmission rod 13 can be changed, thereby adjusting the transmission ratio and pitch stroke of the second drive mechanism. Thus, without replacing parts, the same set of drive components can adapt to the pitch angle, amplitude, and torque requirements of different states or loads.

[0028] Furthermore, the second horizontal plate 4 is provided with a clearance groove to provide clearance space for the moving parts of the second drive mechanism and avoid motion interference. The transmission rod 13 is a connecting rod structure, which can be a straight rod or a curved rod bent according to the spatial arrangement requirements between the second motor 10 and the second connecting rod 8. One end of the transmission rod 13 is rotatably connected to the rotating arm 11 through the hinge shaft 12. The transmission rod 13 is provided with an adjustment through hole 14, the second connecting rod 8 is provided with an adjustment through groove, and the third connecting rod 18 is both embedded in the adjustment through groove of the second connecting rod 8 and passes through the adjustment through hole 14 of the transmission rod 13, realizing the rotational connection between the transmission rod 13 and the second connecting rod 8.

[0029] The ankle device in this embodiment includes pitch and lateral movements. The lateral movement is driven by a first motor 9, whose output is connected to a first connecting rod 7. The housing of the first motor 9 is fixed to a first support. When the first motor 9 operates, its output drives the first connecting rod 7 to rotate. Under the action of the reaction torque, the housing fixed to the first support rotates the first support in the opposite direction relative to the first connecting rod 7, thus achieving the left-right lateral movement of the foot structure 16 relative to the lower leg. The pitch movement is driven by a second motor 10, which drives a rotating arm 11 to rotate through its output. The rotating arm 11 is crank-shaped, and its eccentric hinge shaft 12 rotates around the output with the rotating arm 11, causing one end of the transmission rod 13 to move accordingly. The other end is connected to the second connecting rod 8 via a third connecting rod 18, thereby causing the first support, along with the foot structure 16, to pitch around the axis of the second connecting rod 8, thus achieving the forward and backward pitch of the foot structure 16 relative to the lower leg.

[0030] According to another aspect of the present invention, a robot is also provided, including a body and an ankle device as described above, the ankle device being mounted on the body.

[0031] In conjunction with the above embodiments of this utility model, a cross-axis structure is formed by the mutually perpendicular first connecting rod 7 and second connecting rod 8. The first driving mechanism drives the first support to laterally swing around the first connecting rod 7, and the second driving mechanism drives the first support to pitch around the second connecting rod 8. This gives the foot structure 16 two mutually perpendicular and decoupled rotational degrees of freedom relative to the lower leg: lateral swing and pitch. Compared with a multi-branch parallel structure, this device has a simpler transmission path, fewer friction pairs, and avoids problems such as complex inverse kinematics calculations, assembly delays, and single-point failures caused by motion coupling, significantly improving reliability and maintainability. The first motor 9 and the second motor 10 independently drive two degrees of freedom, eliminating the need for additional decoupling algorithms, thus simplifying the control system and reducing development and maintenance costs. The second motor 10 is positioned above the second horizontal plate 4 via the linkage rod 15, keeping the mass of the driving component away from the foot end, reducing end mass, improving mass distribution, decreasing rotational inertia, and enhancing dynamic response speed. Multiple adjustment through holes 14 along the length of the transmission rod 13, in conjunction with the adjustment through slots on the second connecting rod 8, allow adjustment of the transmission ratio and pitch stroke by changing the insertion position of the third connecting rod 18, enabling the same drive assembly to adapt to different states or loads without replacing any parts. The elastic buffer 17 between the first support and the foot structure 16 absorbs landing impact and improves walking stability, while the clearance slots on the second horizontal plate 4 provide clearance space for moving components. The overall structure is compact, reliable, and easy to maintain.

[0032] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An ankle device for use in a robot, characterized in that, include: The first support is used to install the robot's foot structure (16), and a first connecting rod (7) is rotatably mounted on the first support. The second support is used to support the first support. The first connecting rod (7) is provided with a second connecting rod (8), which is perpendicular to the first connecting rod (7). The second support is rotatably connected to the second connecting rod (8). The drive assembly includes a first drive mechanism and a second drive mechanism; the first drive mechanism is used to drive the first support to rotate around the first connecting rod (7); the second drive mechanism is used to drive the first support to rotate around the second connecting rod (8). The second connecting rod (8) is provided with an adjustment slot, and a third connecting rod (18) is provided in the adjustment slot; the second driving mechanism includes a transmission rod (13), and a plurality of adjustment holes (14) are provided on the transmission rod (13) along the length direction. The third connecting rod (18) is rotatably connected to the transmission rod (13) through the adjustment holes (14).

2. The ankle device as claimed in claim 1, characterized in that, The first support is U-shaped and includes a first horizontal plate (1) and a first vertical plate (2) and a second vertical plate (3) disposed on both sides of the first horizontal plate (1). The foot structure (16) is disposed at the bottom of the first horizontal plate (1).

3. The ankle device as described in claim 2, characterized in that, The first driving mechanism includes a first motor (9), the housing of the first motor (9) is connected to the first vertical plate (2), the output end of the first motor (9) is connected to the first end of the first connecting rod (7), and the second end of the first connecting rod (7) is rotatably connected to the second vertical plate (3).

4. The ankle device as claimed in claim 1, characterized in that, The second support is U-shaped and includes a second horizontal plate (4) and a third vertical plate (5) and a fourth vertical plate (6) disposed on both sides of the second horizontal plate (4). The second connecting rod (8) is disposed between the third vertical plate (5) and the fourth vertical plate (6).

5. The ankle device as described in claim 4, characterized in that, The first connecting rod (7) is provided with a pivot hole, and the second connecting rod (8) passes through the pivot hole.

6. The ankle device as claimed in claim 5, characterized in that, The second drive mechanism also includes a second motor (10) and a rotating arm (11). The output end of the second motor (10) is connected to the rotating arm (11). A hinge shaft (12) is provided on the rotating arm (11). The transmission rod (13) is rotatably connected to the hinge shaft (12).

7. The ankle device as claimed in claim 6, characterized in that, It also includes a linkage rod (15), the bottom of which is connected to the second horizontal plate (4), and the second motor (10) is provided on the side wall of the linkage rod (15).

8. The ankle device as claimed in claim 6, characterized in that, The second horizontal plate (4) is provided with a clearance groove.

9. The ankle device as claimed in claim 1, characterized in that, An elastic buffer (17) is provided between the first support and the foot structure (16).

10. A robot, characterized in that, It includes a body and an ankle device as described in any one of claims 1-9, the ankle device being mounted on the body.

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