Robot ankle structure and robot system
By combining the cross shaft assembly and the drive device, the problems of large transmission error, short lifespan and complex control of robot ankle structures in the prior art are solved, realizing compact and reliable ankle motion control, expanding the range of motion and simplifying algorithm calculation.
Patent Information
- Application Number
- CN202520364581.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-04
- Publication Date
- 2026-01-09
- Estimated Expiration
- 2035-03-04
AI Technical Summary
Existing robot ankle structures suffer from large transmission errors, short lifespan, high maintenance costs, complex motion control, and limited angle range due to the use of joint spherical bearings. Furthermore, the transmission ratio is difficult to calculate accurately under different postures.
The foot plate and the cross shaft assembly are driven by two drive devices to perform pitch and roll movements relative to the lower leg. Vertical shaft transmission is achieved through bevel gear or worm gear meshing, eliminating the joint spherical bearing and using equal-length drive linkages to transmit torque.
This invention achieves a compact, highly reliable, smooth transmission, large range of motion, high transmission accuracy, simple algorithm calculation, and precise motion control ankle structure, reducing maintenance difficulty and cost.
Smart Images
Figure CN223778461U_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to a robotic ankle structure and a robotic system. Background Technology
[0002] In recent years, with the rise of humanoid robots, more and more manufacturers have begun to plan and develop humanoid robots. In humanoid robots, the ankle structure is a key component for enabling the robot to stand and walk.
[0003] In existing ankle structures, there are generally two degrees of freedom: pitch and rotation. The pitch and rotation of the ankle are controlled by two independent motors.
[0004] Because two motors need to be placed in a region similar to the human lower leg, and then the motors transmit power from two degrees of freedom to the ankle, the structure requires a very compact design. A common transmission method is a four-bar linkage with a cross-axis. Each motor transmits power to the sole of the foot via a drive rod. The sole is connected to both ends of one of the cross-axis axes and can rotate around it; this degree of freedom is the ankle's rotational motion. The other axis of the cross-axis is connected to the two support frames of the lower leg and can rotate around them; this degree of freedom is the ankle's pitching motion. The two drive rods and the two support frames on the lower leg form a four-bar linkage. The simultaneous movement of the two drive rods in one direction results in pitching motion, while the movement of the two drive rods in opposite directions results in rotational motion. Since pitching and rotational motions exist simultaneously, and the linear motion of the drive rods is derived from the rotational motion of the motors, spherical bearings are needed at both ends of the drive rods to achieve the two degrees of freedom of ankle rotation.
[0005] While this design offers advantages such as compact structure, simplicity, and low cost, it suffers from several drawbacks. The spherical bearings utilize sliding friction internally and have significantly larger clearances compared to traditional rolling bearings, lacking proper sealing. This results in substantial overall transmission errors, a shorter lifespan, and the need for bearing replacement during maintenance, leading to higher maintenance costs. Furthermore, the power transmission relies on a linkage mechanism, causing the transmission ratio to vary with different postures. Calculating the accurate ankle angle is challenging, making the algorithmic calculation and motion control of this ankle structure complex. Additionally, the relatively small range of motion of the spherical bearings, approaching their limits, can lead to movement pauses or even jamming. This restricts the ankle's range of motion and results in less smooth rotation. Utility Model Content
[0006] To address one of the aforementioned technical problems, this disclosure provides a robotic ankle structure and a robotic system.
[0007] According to one aspect of this disclosure, a robotic ankle structure is provided, comprising:
[0008] A cross-axis assembly is connected to the sole of the foot and the lower leg, wherein the cross-axis assembly has a first axis of rotation between the cross-axis assembly and the sole of the foot, and a second axis of rotation between the cross-axis assembly and the lower leg;
[0009] A first driving device, disposed on the lower leg, is used to drive the foot plate to rotate relative to the cross-axis assembly along a first rotation axis; and
[0010] A second driving device is disposed on the lower leg and is used to drive the cross shaft assembly to rotate relative to the lower leg along a second rotation axis.
[0011] According to at least one embodiment of the robot ankle structure of the present disclosure, the cross axis assembly includes a first shaft portion and a second shaft portion, wherein the first shaft portion is rotatably disposed on the foot plate via a front bearing seat assembly, and the second shaft portion is rotatably disposed on the foot plate via a rear bearing seat assembly, and the axis of the first shaft portion and the axis of the second shaft portion both coincide with a first rotation axis.
[0012] According to at least one embodiment of the robot ankle structure of the present disclosure, the cross axis assembly includes a third axis portion and a fourth axis portion, wherein the third axis portion is rotatably disposed in a mounting hole of the lower leg, and the fourth axis portion is rotatably disposed in another mounting hole of the lower leg.
[0013] According to at least one embodiment of the robotic ankle structure of this disclosure, the cross-axis assembly includes:
[0014] A first transmission member, rotatably disposed within the first shaft portion; and
[0015] The second transmission member is connected to the first transmission member in a transmission manner, wherein the second transmission member is rotatably disposed within the third shaft portion.
[0016] According to at least one embodiment of the robot ankle structure of this disclosure, the front bearing housing assembly includes:
[0017] A front bearing housing assembly, the front bearing housing assembly being fixed to the foot plate; wherein, the first shaft portion is rotatably disposed on the front bearing housing assembly via a front axle sleeve; and
[0018] A front adapter shaft is connected to the first transmission member and is fixed to the front bearing housing component.
[0019] According to at least one embodiment of the robot ankle structure of this disclosure, the second transmission member is connected to the first driving device to drive the second transmission member to rotate via the first driving device.
[0020] According to at least one embodiment of the robot ankle structure of this disclosure, the first driving device includes:
[0021] A first motor, the first motor being fixed to the lower leg; and
[0022] A first drive disk is disposed on the first motor, and the first motor drives the first drive disk to rotate; wherein, at least one first active bearing column is disposed on the first drive disk.
[0023] According to at least one embodiment of the robot ankle structure of this disclosure, the second transmission member is fixedly connected to the first driven disk, wherein at least one first driven bearing post is provided on the first driven disk; one end of the first drive link is rotatably disposed on the first drive bearing post of the first drive disk, and the other end of the first drive link is rotatably disposed on the first driven bearing post of the first driven disk.
[0024] According to at least one embodiment of the robot ankle structure of this disclosure, the first drive link is configured as one or two; when the first drive link is configured as two, the two first drive links are arranged in parallel.
[0025] According to at least one embodiment of the robot ankle structure of this disclosure, the second drive device includes:
[0026] A second motor, the second motor being fixed to the lower leg; and
[0027] The second drive disk is disposed on the second motor, and the second motor drives the second drive disk to rotate; wherein, the second drive disk is provided with at least one second driven bearing column.
[0028] According to at least one embodiment of the robot ankle structure of this disclosure, the fourth axis is fixedly connected to the second driven disk, wherein at least one second driven bearing post is provided on the second driven disk; one end of the second drive link is rotatably disposed on the second drive bearing post of the second drive disk, and the other end of the second drive link is rotatably disposed on the second driven bearing post of the second driven disk.
[0029] The second drive link is set to one or two; when the second drive link is set to two, the two second drive links are arranged in parallel.
[0030] According to at least one embodiment of the robot ankle structure of the present disclosure, the first drive link and the second drive link are respectively located on opposite sides of the lower leg.
[0031] According to another aspect of this disclosure, a robotic system is provided that includes the aforementioned robotic ankle structure. Attached Figure Description
[0032] The accompanying drawings illustrate exemplary embodiments of the present disclosure and, together with the description thereof, serve to explain the principles of the present disclosure. These drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification.
[0033] Figure 1 This is a schematic diagram of a robot ankle structure according to one embodiment of the present disclosure.
[0034] Figures 2 to 4 This is a schematic diagram of the robot ankle structure at different angles according to one embodiment of the present disclosure.
[0035] Figure 5 This is a schematic diagram of the cross-axis assembly of a robot ankle structure according to one embodiment of the present disclosure.
[0036] Figure 6 This is a cross-sectional structural schematic diagram of the cross shaft assembly of a robot ankle structure according to one embodiment of the present disclosure.
[0037] Figure 7 This is a cross-sectional schematic diagram of a robot ankle structure according to one embodiment of the present disclosure.
[0038] Figure 8 This is a schematic diagram of the lower leg structure of a robot ankle mechanism according to one embodiment of the present disclosure.
[0039] Figure 9 This is a schematic diagram of the structure of a front bearing housing assembly according to one embodiment of the present disclosure.
[0040] Figure 10 This is a structural schematic diagram of a rear bearing housing assembly according to one embodiment of the present disclosure.
[0041] Figure 11 This is a schematic diagram of the structure of a first driving device according to an embodiment of the present disclosure.
[0042] Figure 12 and Figure 13 This is a structural schematic diagram of the first driven disk at different angles according to one embodiment of the present disclosure.
[0043] Figure 14This is a schematic diagram of the structure of the second driven disk according to one embodiment of the present disclosure.
[0044] Figure 15 This is a schematic diagram of the flipping motion of a robot ankle structure according to one embodiment of the present disclosure.
[0045] Figure 16 This is a schematic diagram of the pitch motion of a robot ankle structure according to one embodiment of the present disclosure.
[0046] The specific labels in the attached figures are as follows:
[0047] 10. Calf
[0048] 11 Limiting contact surface
[0049] 20. Foot soles
[0050] 100 Cross Shaft Assembly
[0051] 110 First Shaft
[0052] 120 Second Shaft
[0053] 130 Third Shaft
[0054] 140 Fourth Shaft
[0055] 150 First transmission component
[0056] 160 Second transmission component
[0057] 170 First driven disk
[0058] 171 First driven bearing column
[0059] 180 Second driven plate
[0060] 181 Second driven bearing column
[0061] 200 First drive unit
[0062] 210 First Electric Machine
[0063] 220 First drive disk
[0064] 230 First drive bearing column
[0065] 300 Second Drive Unit
[0066] 400 front bearing housing assembly
[0067] 410 Front bearing housing assembly
[0068] 420 front adapter shaft
[0069] 430 front axle bushing
[0070] 500 rear bearing housing assembly
[0071] 510 Rear Bearing Housing Component
[0072] 600 First drive linkage
[0073] 700 Second drive linkage. Detailed Implementation
[0074] The present disclosure will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the disclosure. Furthermore, it should be noted that, for ease of description, only the parts relevant to the present disclosure are shown in the accompanying drawings.
[0075] It should be noted that, where there is no conflict, the embodiments and features described in this disclosure can be combined with each other. The technical solutions of this disclosure will now be described in detail with reference to the accompanying drawings and embodiments.
[0076] Unless otherwise stated, the exemplary implementations / embodiments shown are to be understood as providing exemplary features of various details that provide ways in which the technical concepts of this disclosure can be implemented in practice. Therefore, unless otherwise stated, the features of various implementations / embodiments may be additionally combined, separated, interchanged and / or rearranged without departing from the technical concepts of this disclosure.
[0077] The use of crosshairs and / or shading in the accompanying drawings is generally used to clarify the boundaries between adjacent components. Thus, unless otherwise stated, the presence or absence of crosshairs or shading does not convey or indicate any preference or requirement for the specific material, material properties, dimensions, proportions, commonalities between the illustrated components, or any other characteristics, properties, etc., of the components. Furthermore, in the accompanying drawings, the dimensions and relative dimensions of components may be exaggerated for clarity and / or descriptive purposes. When exemplary embodiments can be implemented differently, a specific process sequence may be performed in a different order than that described. For example, two consecutively described processes may be performed substantially simultaneously or in the reverse order of their description. Furthermore, the same reference numerals denote the same components.
[0078] When a component is referred to as being "on" or "above" another component, "connected to," or "joined to" another component, the component may be directly on, directly connected to, or directly joined to the other component, or there may be intermediate components. However, when a component is referred to as being "directly on" another component, "directly connected to," or "directly joined to" another component, there are no intermediate components. Therefore, the term "connection" can refer to a physical connection, an electrical connection, etc., and may or may not have intermediate components.
[0079] For descriptive purposes, this disclosure may use spatial relative terms such as “below,” “under,” “below,” “down,” “above,” “above,” “higher,” and “side (e.g., in a “sidewall”)” to describe the relationship between one component and another component as shown in the accompanying drawings. In addition to the orientations depicted in the drawings, the spatial relative terms are also intended to encompass different orientations of the device during use, operation, and / or manufacture. For example, if the device in the drawings is flipped, a component described as “below” or “under” another component or feature would subsequently be positioned “above” said other component or feature. Thus, the exemplary term “below” can encompass both “above” and “below” orientations. Furthermore, the device may be otherwise positioned (e.g., rotated 90 degrees or in other orientations), thus interpreting the spatial relative descriptive terms used herein accordingly.
[0080] The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, unless the context clearly indicates otherwise, the singular forms “a” and “the” are intended to include the plural forms as well. Furthermore, when the terms “comprising” and / or “including” and variations thereof are used in this specification, it indicates the presence of the stated features, integrals, steps, operations, parts, components, and / or groups thereof, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, parts, components, and / or groups thereof. It should also be noted that, as used herein, the terms “substantially,” “about,” and other similar terms are used as approximate terms rather than as terms of degree, thus explaining the inherent biases in measurements, calculated values, and / or provided values that would be recognized by one of ordinary skill in the art.
[0081] Figure 1 This is a schematic diagram of a robot ankle structure according to one embodiment of the present disclosure. Figures 2 to 4 This is a schematic diagram of the robot ankle structure at different angles according to one embodiment of the present disclosure.
[0082] like Figures 1 to 4As shown, the robot ankle structure disclosed herein may include components such as a cross shaft assembly 100, a first drive device 200, and a second drive device 300.
[0083] The cross-axis assembly 100 connects the foot sole 20 and the lower leg 10. The cross-axis assembly 100 and the foot sole 20 have a first axis of rotation (forward-backward rotation axis), and the cross-axis assembly 100 and the lower leg 10 have a second axis of rotation (left-right rotation axis). Specifically, the first axis of rotation is a straight line along the length of the foot sole 20, and the second axis of rotation is a straight line along the width of the foot sole 20. Correspondingly, the first axis of rotation and the second axis of rotation intersect perpendicularly. That is, the first axis of rotation and the second axis of rotation lie within a certain horizontal plane.
[0084] A first driving device 200 is disposed on the lower leg 10 for driving the foot plate 20 to rotate relative to the cross shaft assembly 100 along a first rotation axis; and a second driving device 300 is disposed on the lower leg 10 for driving the cross shaft assembly 100 to rotate relative to the lower leg 10 along a second rotation axis.
[0085] Therefore, the robot ankle structure disclosed herein realizes the pitch and roll motion of the lower leg 10 and the foot plate 20 through two drive devices, which can accurately simulate the human ankle joint; moreover, the robot ankle structure disclosed herein has the advantages of compact structure, high reliability, easy maintenance, smooth transmission, large range of motion, high transmission accuracy, simple algorithm calculation, and precise motion control through the setting of the cross axis assembly.
[0086] The robot ankle structure of this disclosure will be described in detail below with reference to the accompanying drawings.
[0087] Figure 5 This is a schematic diagram of the cross-axis assembly of a robot ankle structure according to one embodiment of the present disclosure. Figure 6 This is a cross-sectional structural schematic diagram of the cross shaft assembly of a robot ankle structure according to one embodiment of the present disclosure. Figure 7 This is a cross-sectional schematic diagram of a robot ankle structure according to one embodiment of the present disclosure.
[0088] like Figures 5 to 7 As shown, the cross shaft assembly 100 of this disclosure includes a central component and components such as a first shaft portion 110, a second shaft portion 120, a third shaft portion 130, and a fourth shaft portion 140 connected to the central component.
[0089] The central component of this disclosure is formed as a hollow component, i.e., it has two perpendicularly intersecting central holes. The first shaft portion 110 of this disclosure is formed as a cylindrical structure, which can be integrally formed with the central component. The first shaft portion 110 is rotatably mounted on the foot plate 20 via the front bearing seat assembly 400.
[0090] The second shaft portion 120 of this disclosure can be formed as a columnar structure, or it can be integrally formed with the central component. The second shaft portion 120 is rotatably mounted on the foot plate 20 via the rear bearing seat assembly 500, and the axis of both the first shaft portion 110 and the axis of the second shaft portion 120 coincide with the first rotation axis.
[0091] That is, the first shaft portion 110 and the second shaft portion 120 of this disclosure are located on opposite sides of the central component, and the first shaft portion 110 and the second shaft portion 120 have the same axis.
[0092] Figure 8 This is a schematic diagram of the lower leg structure of a robot ankle mechanism according to one embodiment of the present disclosure.
[0093] like Figure 8 As shown, the lower end of the lower leg 10 of this disclosure has two mounting holes (bearing holes), and a bushing is provided in each mounting hole. For example, the bushing can be fixed in the mounting hole of the lower leg 10 by means of adhesive or interference fit; at this time, the third shaft portion 130 is rotatably disposed in one bushing, and the fourth shaft portion 140 is rotatably disposed in the other bushing. Thus, the cross shaft assembly 100 of this disclosure can rotate relative to the lower leg 10, and correspondingly, the foot plate 20 can rotate relative to the lower leg 10.
[0094] In this disclosure, a limiting contact surface 11 is provided on the lower leg 10. Two limiting contact surfaces 11 are provided. One of the limiting contact surfaces 11 can contact the front bearing housing assembly 400, thereby limiting the rotation angle of the foot plate 20 relative to the lower leg 10 in one direction. Similarly, the other limiting contact surface 11 can contact the rear bearing housing assembly 500, thereby limiting the rotation angle of the foot plate 20 relative to the lower leg 10 in another direction. These two directions are opposite rotation directions. Therefore, the robot ankle structure of this disclosure has a mechanical limiting structure, and the movement of the foot plate 20 is controlled within a certain range.
[0095] See again Figure 6 The cross shaft assembly 100 of this disclosure further includes a first transmission member 150 and a second transmission member 160; the first transmission member 150 is rotatably disposed within the first shaft portion 110; the second transmission member 160 is connected to the first transmission member 150 in a transmission connection, wherein the second transmission member 160 is rotatably disposed within the third shaft portion 130, thereby forming a vertical shaft transmission connection relationship between the first transmission member 150 and the second transmission member 160 of this disclosure.
[0096] In a preferred embodiment, the first transmission member 150 and the second transmission member 160 may have the same structure. For example, both the first transmission member 150 and the second transmission member 160 include a gear shaft and a bevel gear mounted on the gear shaft. Thus, the first transmission member 150 and the second transmission member 160 achieve vertical shaft transmission through the meshing of the bevel gears.
[0097] In another preferred embodiment, the first transmission member 150 can be a worm, and the second transmission member 160 can be a worm wheel, thereby achieving vertical shaft transmission through the meshing of the worm wheel and worm.
[0098] Specifically, such as Figure 7 As shown, the gear shaft of the first transmission member 150 is provided with two bearings, and a shim is provided between the two bearings. Moreover, the inner ring of one of the bearings is restricted in position by the shoulder of the gear shaft of the first transmission member 150, and the outer ring of the other bearing is restricted in position by a snap ring installed on the first shaft portion 110. Thus, the two bearings will not change position in the axial direction.
[0099] Similarly structured, the gear shaft of the second transmission member 160 is provided with two bearings, with a shim between the two bearings. Furthermore, the inner ring of one of the bearings is restricted in position by the shoulder of the gear shaft of the second transmission member 160, and the outer ring of the other bearing is restricted in position by a snap ring installed on the third shaft portion 130. Thus, the two bearings will not change position in the axial direction.
[0100] Figure 9 This is a schematic diagram of the structure of a front bearing housing assembly according to one embodiment of the present disclosure.
[0101] like Figure 9 As shown, the front bearing housing assembly 400 of this disclosure includes a front bearing housing component 410 and a front adapter shaft 420; wherein, the front bearing housing component 410 is fixed to the foot plate 20; the first shaft portion 110 is rotatably disposed on the front bearing housing component 410 via a front axle sleeve; the front adapter shaft 420 is connected to the first transmission member 150, and the front adapter shaft 420 is fixed to the front bearing housing component 410.
[0102] Specifically, the gear shaft of the first transmission member 150 disclosed herein has a bevel gear at one end and a keyway at the other end; at the same time, a central hole is formed at one end of the front adapter shaft 420, and the other end of the gear shaft of the first transmission member 150 can be inserted into one end of the front adapter shaft 420. Moreover, a keyway is also formed at one end of the front adapter shaft 420. Correspondingly, keys can be provided in the keyway of the first transmission member 150 and the keyway of the front adapter shaft 420, so that no relative rotation occurs between the first transmission member 150 and the front adapter shaft 420.
[0103] In addition, the other end of the front adapter shaft 420 can be fixed to the front bearing housing component 410 by means of a pin or other structure. As a result, the first transmission member 150 will not rotate relative to the front bearing housing component 410. At this time, when the second transmission member 160 rotates and drives the first transmission member 150 to rotate, the front bearing housing component 410 can rotate relative to the first shaft portion 110. At this time, the foot plate 20 will rotate together with the front bearing housing component 410 relative to the first shaft portion 110.
[0104] The front bearing housing component 410 of this disclosure is provided with a front axle sleeve 430, and the first shaft portion 110 is rotatably disposed on the front bearing housing assembly 400 via the front axle sleeve 430.
[0105] Figure 10 This is a structural schematic diagram of a rear bearing housing assembly according to one embodiment of the present disclosure.
[0106] like Figure 10 As shown, the rear bearing housing assembly 500 of this disclosure includes a rear bearing housing component 510, which has two bearings disposed therein, and the two bearings can be spaced apart by a shim.
[0107] See again Figure 6 The second shaft portion 120 is provided with a shoulder, and the inner ring of one of the two bearings can be restricted in its axial position by the shoulder of the second shaft portion 120. The outer ring of the other bearing can be restricted in its position by a snap ring installed on the rear bearing housing assembly 500. Thus, the axial position of the two bearings will be accurately defined.
[0108] The second transmission component 160 is connected to the first driving device 200 so as to drive the second transmission component 160 to rotate through the first driving device 200.
[0109] Figure 11 This is a schematic diagram of the structure of a first driving device according to an embodiment of the present disclosure.
[0110] like Figure 11 As shown, the first driving device 200 of this disclosure includes components such as a first motor 210 and a first driving disk 220. The first motor 210 is fixed to the lower leg 10; the first driving disk 220 is disposed on the first motor 210, and the first motor 210 drives the first driving disk 220 to rotate; wherein, at least one first active bearing column 230 is disposed on the first driving disk 220.
[0111] exist Figure 11 In the specific embodiment shown, the number of the first active bearing post 230 is one or two. When the first active bearing post 230 is set to two, the two first active bearing posts 230 are set at a circumferential interval of 180 degrees along the first drive disk 220.
[0112] Figure 12 and Figure 13 This is a structural schematic diagram of the first driven disk at different angles according to one embodiment of the present disclosure.
[0113] See again Figure 6 , Figure 12 and Figure 13 The second transmission member 160 is fixedly connected to the first driven disk 170. For example, the gear shaft of the second transmission member 160 can be fixed to the first driven disk 170 by screws, and the second transmission member 160 and the first driven disk 170 are also connected by a key structure so that there is no relative rotation between the second transmission member 160 and the first driven disk 170.
[0114] At least one first driven bearing post 171 is provided on the first driven disk 170; one end of the first drive link 600 is rotatably mounted on the first drive bearing post 230 of the first drive disk 220 via a bearing, and the other end of the first drive link 600 is rotatably mounted on the first driven bearing post 171 of the first driven disk 170 via a bearing. Thus, when the first motor 210 rotates, the first driven disk 170 can rotate in the same direction. The bearing can be fixed in the bearing holes at both ends of the first drive link 600 by interference fit, welding, or adhesive bonding.
[0115] In one specific embodiment, one or two first drive links 600 are provided. When two first drive links 600 are provided, the two first drive links 600 have the same structure and are arranged in parallel. In addition, the transmission method implemented by the first drive links 600 in this disclosure can be replaced by a synchronous belt pulley structure or a rope-driven winch structure.
[0116] Similar to the structure of the first driving device 200, the second driving device 300 of this disclosure includes a second motor and a second driving disk; the second motor is fixed to the lower leg 10; the second driving disk is disposed on the second motor, and the second motor drives the second driving disk to rotate; wherein, at least one second driven bearing column 181 is disposed on the second driving disk.
[0117] Figure 14 This is a schematic diagram of the structure of the second driven disk 180 according to one embodiment of the present disclosure.
[0118] The fourth shaft portion 140 is fixedly connected to the second driven disk 180, wherein at least one second driven bearing post 181 is provided on the second driven disk 180; one end of the second drive connecting rod 700 is rotatably mounted on the second drive bearing post of the second drive disk via a bearing, and the other end of the second drive connecting rod 700 is rotatably mounted on the second driven bearing post 181 of the second driven disk 180 via a bearing. The bearing can be fixed in the bearing holes at both ends of the second drive connecting rod 700 by means of interference fit, welding, or adhesive bonding.
[0119] In one specific embodiment, the second drive link 700 of this disclosure is configured as one or two. When two second drive links 700 are configured, the two second drive links 700 have the same structure and are arranged in parallel. Furthermore, the transmission method implemented by the second drive link 700 of this disclosure can be replaced by a synchronous pulley structure or a rope-driven winch structure.
[0120] Based on the above structure, the robot ankle mechanism of this disclosure achieves two degrees of freedom—ankle pitch and ankle rotation—by setting bevel gears inside the cross-axis assembly. The structure is compact. Since the motor transmits rotational torque to the cross-axis assembly, unlike traditional solutions that require ball bearings to convert the motor's rotational torque into a linear push-pull force on the drive rods, this robot ankle mechanism eliminates the need for large-clearance ball bearings and easily deformable four-bar push-pull structures. Instead, each motor transmits torque via two equally long drive rods. The transmission ratio of the ankle pitch and ankle rotation degrees of freedom is constant, resulting in small transmission errors, simple algorithm calculation and motion control, high reliability, and easy maintenance. Furthermore, the ankle pitch and rotation angles are not limited by the absence of ball bearings, allowing for a larger range of motion and smooth rotation.
[0121] In addition, the first drive device 200 and the second drive device 300 of this disclosure can be arranged in opposite directions. Correspondingly, the first driven plate 170 and the second driven plate 180 can be located at the two ends of the coaxial cross shaft assembly, which facilitates the arrangement of the first drive link and the second drive link.
[0122] According to another aspect of this disclosure, a robot system is provided, which can be a bipedal robot system, and the bipedal robot system can include the robot ankle structure described above.
[0123] In the description of this specification, the references to terms such as "one embodiment / mode," "some embodiments / modes," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment / mode or example is included in at least one embodiment / mode or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment / mode or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments / modes or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments / modes or examples described in this specification, as well as the features of different embodiments / modes or examples.
[0124] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0125] Those skilled in the art should understand that the above embodiments are merely for illustrating the present disclosure and are not intended to limit the scope of the disclosure. Those skilled in the art can make other changes or modifications based on the above disclosure, and these changes or modifications still fall within the scope of the present disclosure.
Claims
1. A robot ankle structure, characterized in that, include: A cross-axis assembly is connected to the sole of the foot and the lower leg, wherein the cross-axis assembly has a first axis of rotation between the cross-axis assembly and the sole of the foot, and a second axis of rotation between the cross-axis assembly and the lower leg; A first driving device, disposed on the lower leg, is used to drive the foot plate to rotate relative to the cross-axis assembly along a first rotation axis; and A second driving device is disposed on the lower leg and is used to drive the cross shaft assembly to rotate relative to the lower leg along a second rotation axis.
2. The robot ankle structure according to claim 1, characterized in that, The cross shaft assembly includes a first shaft portion and a second shaft portion, wherein the first shaft portion is rotatably mounted on the foot plate via a front bearing seat assembly, and the second shaft portion is rotatably mounted on the foot plate via a rear bearing seat assembly, and the axis of the first shaft portion and the axis of the second shaft portion both coincide with the first rotation axis.
3. The robot ankle structure according to claim 2, characterized in that, The cross shaft assembly includes a third shaft portion and a fourth shaft portion, wherein the third shaft portion is rotatably disposed in one mounting hole of the lower leg, and the fourth shaft portion is rotatably disposed in another mounting hole of the lower leg.
4. The robot ankle structure according to claim 3, characterized in that, The cross shaft assembly includes: A first transmission member, rotatably disposed within the first shaft portion; and The second transmission member is connected to the first transmission member in a transmission manner, wherein the second transmission member is rotatably disposed within the third shaft portion.
5. The robot ankle structure according to claim 4, characterized in that, The front bearing housing assembly includes: A front bearing housing assembly, the front bearing housing assembly being fixed to the foot plate; wherein, the first shaft portion is rotatably disposed on the front bearing housing assembly via a front axle sleeve; and A front adapter shaft is connected to the first transmission member and is fixed to the front bearing housing component.
6. The robot ankle structure according to claim 5, characterized in that, The second transmission component is connected to the first driving device so as to drive the second transmission component to rotate through the first driving device.
7. The robot ankle structure according to claim 6, characterized in that, The first driving device includes: A first motor, the first motor being fixed to the lower leg; and A first drive disk is disposed on the first motor, and the first motor drives the first drive disk to rotate; wherein, at least one first active bearing column is disposed on the first drive disk.
8. The robot ankle structure according to claim 7, characterized in that, The second transmission component is fixedly connected to the first driven disk, wherein at least one first driven bearing post is provided on the first driven disk; one end of the first drive link is rotatably disposed on the first drive bearing post of the first drive disk, and the other end of the first drive link is rotatably disposed on the first driven bearing post of the first driven disk.
9. The robot ankle structure according to claim 8, characterized in that, The first drive link is set to one or two; when the first drive link is set to two, the two first drive links are arranged in parallel.
10. The robot ankle structure according to claim 8, characterized in that, The second driving device includes: A second motor, the second motor being fixed to the lower leg; and The second drive disk is disposed on the second motor, and the second motor drives the second drive disk to rotate; wherein, the second drive disk is provided with at least one second driven bearing column.
11. The robot ankle structure according to claim 10, characterized in that, The fourth shaft is fixedly connected to the second driven disk, wherein at least one second driven bearing post is provided on the second driven disk; one end of the second drive link is rotatably provided on the second drive bearing post of the second drive disk, and the other end of the second drive link is rotatably provided on the second driven bearing post of the second driven disk.
12. The robot ankle structure according to claim 11, characterized in that, The second drive link is set to one or two; when the second drive link is set to two, the two second drive links are arranged in parallel.
13. The robot ankle structure according to claim 11, characterized in that, The first drive link and the second drive link are located on opposite sides of the lower leg, respectively.
14. A robot system, characterized in that, Includes the robot ankle structure according to any one of claims 1-13.