Joint assembly, leg structure and humanoid robot

Abstract

The utility model belongs to the technical field of humanoid robots, and discloses a joint assembly, a leg structure and a humanoid robot, the joint assembly is arranged between a first component and a second component which are rotatably connected, the joint assembly comprises a first connecting rod, a second connecting rod and a linear actuator, and the first end of the first connecting rod is rotatably connected with the first component through a first shaft group; the first end of the second connecting rod is rotationally connected with the second end of the first connecting rod through a second shaft set, and the second end of the second connecting rod is rotationally connected with the second component through a third shaft set. The linear actuator is rotationally connected with the second connecting rod through a fourth shaft set, and the fourth shaft set and the first shaft set are arranged in a staggered mode. The leg structure comprises the joint assembly, and the humanoid robot comprises the leg structure or the joint assembly. The joint assembly, the leg structure and the humanoid robot are low in manufacturing cost.

Description

Technical Field

[0001] This utility model relates to the field of robotics technology, and in particular to a joint assembly, leg structure, and humanoid robot. Background Technology

[0002] Humanoid robots are robots designed to mimic human appearance and behavior. These robots typically integrate advanced technologies from multiple fields, including mechanics, electronics, computer science, materials science, sensor technology, and control theory. For humanoid robots to perform various complex and diverse tasks like humans, they need flexible movement capabilities. However, achieving highly maneuverable and flexible movement requires designing a structural platform with similar or even superior human movement capabilities, selecting appropriate joint drive methods, and possessing ample power to ensure smooth operation under various complex working conditions.

[0003] The leg structure of a humanoid robot includes the hip joint, thigh, knee joint, calf, ankle joint, and foot. To achieve joint movement, most systems currently employ one of two approaches: one is to directly install joint drives and rotary actuators at the corresponding joint positions. This approach results in a large moment of inertia in the legs, affecting the humanoid robot's response speed and dynamic stability.

[0004] To address this, a humanoid robot has been proposed that integrates hip and knee linear actuators onto the thigh support, and ankle actuators onto the lower leg support. This fully utilizes the space on the thigh and lower leg supports, reduces the inertia of the leg structure, and improves the robot's response speed and dynamic stability. However, the hip and knee linear actuators in this humanoid robot require high power, resulting in high manufacturing costs. Utility Model Content

[0005] The purpose of this invention is to provide a joint assembly, leg structure, and humanoid robot to solve the problem of high manufacturing cost of humanoid robots caused by the high power required for the hip or knee linear actuators.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] A joint assembly is disposed between a first component and a second component that are rotatably connected. The joint assembly includes a first link, a second link, and a linear actuator. The first end of the first link is rotatably connected to the first component via a first shaft group. The first end of the second link is rotatably connected to the second end of the first link via a second shaft group, and the second end of the second link is rotatably connected to the second component via a third shaft group. The linear actuator is rotatably connected to the second link via a fourth shaft group, and the fourth shaft group is offset from the first shaft group.

[0008] A leg structure includes a rotating support, a thigh support, a calf support, a hip joint assembly, a knee joint assembly, a foot, and an ankle joint assembly. The thigh support is rotatably connected to the rotating support via a fifth axis group. The hip joint assembly is connected to the rotating support and the thigh support to control their relative rotation. The thigh support is rotatably connected to the calf support via a sixth axis group. The knee joint assembly is connected to the thigh support and the calf support to control their relative rotation. The foot is rotatably connected to the calf support. The ankle joint assembly is connected to the foot and the calf support to control their rotation. The hip joint assembly and / or the knee joint assembly employs the aforementioned joint assemblies.

[0009] Optionally, the knee joint assembly includes a first knee joint link, a second knee joint link, and a knee joint linear actuator. The first knee joint link is rotatably connected to the lower leg support, and the second knee joint link is rotatably connected to the thigh support. The fixed end of the knee joint linear actuator is connected to the thigh support via an eighth axis group, and the knee joint linear actuator controls the relative rotation of the second knee joint link and the first knee joint link. The hip joint assembly includes a first hip joint link, a second hip joint link, and a hip joint linear actuator. The first hip joint link is rotatably connected to the rotary support, and the second hip joint link is rotatably connected to the thigh support. The fixed end of the hip joint linear actuator is connected to the thigh support via a seventh axis group.

[0010] Optionally, the thigh support is integrated into a single unit, comprising a left leg plate and a right leg plate spaced apart, with the hip joint assembly and the knee joint assembly both disposed between the left leg plate and the right leg plate.

[0011] Optionally, the sixth axis group includes two coaxially spaced rotating shafts. The end of the lower leg support that connects to the thigh support is Y-shaped and has shaft mounting holes on both the left and right sides. One of the rotating shafts passes through the shaft mounting hole on the left side of the lower leg support and connects to the left leg plate, while the other rotating shaft passes through the shaft mounting hole on the right side of the lower leg support and connects to the right leg plate.

[0012] Optionally, the calf support is connected to the foot via a rotary cross shaft, which includes a ninth axis group and a tenth axis group. Both the ninth axis group and the tenth axis group are provided with a rotating shaft. The rotating shaft in the ninth axis group extends in the front-back direction, and the rotating shaft in the tenth axis group extends in the left-right direction.

[0013] Optionally, the ankle joint assembly includes two linear actuators, and the ankle joint assembly also includes an eleventh axis group and a twelfth axis group. The fixed ends of the two linear actuators are rotatably connected to the lower leg support through the eleventh axis group, and the output ends of the two linear actuators are rotatably connected to the foot through the twelfth axis group. The eleventh axis group and the twelfth axis group each have a rotating shaft and a joint bearing sleeved on the rotating shaft.

[0014] Optionally, in the two linear actuators of the ankle joint assembly, at least one of the two joint bearings located at both ends of the same linear actuator has a limiting protrusion spaced apart from the front and rear, and the line connecting the two limiting protrusions passes through the shaft corresponding to the joint bearing.

[0015] Optionally, in the first shaft group, the second shaft group, the third shaft group, the fourth shaft group, the eighth shaft group, the ninth shaft group, and the tenth shaft group, at least one shaft group is connected to a first connected member and a second connected member. The first connected member is provided with a first mounting plate and a second mounting plate at intervals. The second connected member is located between the first mounting plate and the second mounting plate. The rotating shaft in at least one shaft group is detachably connected to the first connected member and the second connected member. The two ends of the rotating shaft of the shaft group are respectively connected to the first mounting plate and the second mounting plate.

[0016] Optionally, the shaft that is detachably connected to the first and second connected members is configured as a T-shape, and the shaft assembly further includes a bushing that is fixed to the tail of the shaft by fastening screws.

[0017] Optionally, the head of the rotating shaft is non-circular, and the first mounting plate has a countersunk hole for circumferentially limiting the rotating shaft; and / or, the bushing is non-circular, and the second mounting plate has a countersunk hole for circumferentially limiting the bushing.

[0018] Optionally, the shaft assembly further includes rolling bearings, and the second connected member has bearing mounting holes at both axial ends for mounting the rolling bearings, and the rolling bearings are mounted in each of the bearing mounting holes.

[0019] Optionally, the shaft assembly further includes a spacer sleeve, which is disposed between two rolling bearings on the same rotating shaft and abuts against both rolling bearings. The rolling bearing near the head of the rotating shaft abuts against a shoulder provided on the rotating shaft, and the rolling bearing near the tail of the rotating shaft abuts against the bushing.

[0020] Optionally, a double-rotating screw is provided between the fixed end of the linear actuator in the ankle joint assembly and the joint bearing of the eleventh axis group, and / or, the double-rotating screw is provided between the output end of the linear actuator in the ankle joint assembly and the joint bearing of the twelfth axis group.

[0021] Optionally, the foot has a built-in six-dimensional force sensor.

[0022] Humanoid robot, including the leg structure described in any of the above.

[0023] Humanoid robot, including the aforementioned joint assembly.

[0024] The beneficial effects of this utility model are:

[0025] The joint assembly, leg structure, and humanoid robot of this invention have a fourth axis group connecting the linear actuator and the second link that is offset from the first axis group connecting the first link and the second link. When the linear actuator extends and retracts and acts on the joint assembly, it has its own rotational torque. Compared with the linear actuator acting directly on the first axis group, this reduces the power required for the linear actuator to drive the relative rotation of the first and second components, thus reducing the manufacturing cost of the humanoid robot using this joint assembly. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the leg structure shown in an embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of the thigh structure shown in an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the exploded structure of the thigh shown in an embodiment of this utility model;

[0029] Figure 4 This is a cross-sectional view of the shaft assembly connected to the first and second components as shown in an embodiment of the present invention;

[0030] Figure 5 This is a schematic diagram of the structure of the rotating shaft shown in the embodiment of this utility model;

[0031] Figure 6 This is a schematic diagram of the bushing body shown in an embodiment of the present utility model;

[0032] Figure 7 This is an assembly drawing of the bushing body shown in an embodiment of the present utility model;

[0033] Figure 8 This is an assembly diagram of the rotating shaft shown in an embodiment of this utility model;

[0034] Figure 9 This is a schematic diagram of the connection structure between the thigh and the lower leg in this practical embodiment;

[0035] Figure 10 This is an exploded view of the thigh and lower leg in an embodiment of this utility model;

[0036] Figure 11 This is a force analysis diagram of the joint assembly in an embodiment of this utility model;

[0037] Figure 12 This is a rear view of the connection between the thigh and the lower leg in an embodiment of this utility model;

[0038] Figure 13 This is a partial sectional view of the connection between the thigh and the lower leg in an embodiment of this utility model;

[0039] Figure 14 This is a schematic diagram of the connection structure between the lower leg and the foot in an embodiment of this utility model;

[0040] Figure 15 This is a cross-sectional view of the lower leg and foot in an embodiment of this utility model;

[0041] Figure 16 This is an exploded structural diagram of the lower leg and foot in an embodiment of this utility model;

[0042] Figure 17 This is an exploded structural diagram of the linear actuator in the ankle joint assembly in an embodiment of this utility model;

[0043] Figure 18 This is an exploded structural diagram of the foot shell in an embodiment of this utility model.

[0044] In the picture:

[0045] 1. Rotary support; 2. Thigh support; 21. Left leg plate; 22. Right leg plate; 23. Crossbeam; 3. Lower leg support; 4. Hip joint assembly; 5. Knee joint assembly; 6. Ankle joint assembly; 7. Fifth axis group; 8. Sixth axis group; 9. Seventh axis group; 10. Eighth axis group; 20. Rotary cross axis; 210. Ninth axis group; 220. Tenth axis group; 230. Cross axis support; 30. Foot; 310. Ankle support; 320. Foot shell; 330. Six-dimensional force sensor;

[0046] 101. Shaft; 102. Bushing; 103. Rolling bearing; 104. Fastening screw; 105. Spacer; 106. Bearing retaining ring; 107. Shaft retaining ring; 108. Spherical plain bearing; 109. Limiting protrusion;

[0047] 201. First connected component; 2011. First mounting plate; 2012. Second mounting plate; 202. Second connected component;

[0048] 301. First connecting rod; 302. Second connecting rod; 303. First shaft group; 304. Second shaft group; 305. Third shaft group; 306. Fourth shaft group; 307. Linear actuator; 308. Eleventh shaft group; 309. Twelfth shaft group; 3010. Double-rotating screw; 3020. Self-locking nut. Detailed Implementation

[0049] The present invention 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 merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not the entire structure.

[0050] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0051] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0052] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0053] In related technologies, humanoid robots utilize two links to achieve relative rotation between the thigh and lower leg. These links are rotatably connected to the thigh and lower leg respectively. The two links are connected to a rotating shaft, which is connected to a linear actuator. The linear actuator drives the rotating shaft to change the angle between the two links, thereby achieving rotation between the thigh and lower leg. However, the linear actuator requires high power, which increases the manufacturing cost of the humanoid robot.

[0054] To solve the above problems, refer to Figures 1-18 As shown, an embodiment of this utility model proposes a joint assembly for use in a humanoid robot. The joint assembly is disposed between a first component and a second component that are rotatably connected. The first component and the second component can be the thigh and lower leg in the leg structure of the humanoid robot, or the thigh and hip in the leg structure of the humanoid robot, or the upper arm and forearm in the arm structure of the humanoid robot. The joint assembly includes a linear actuator 307, a first link 301, a second link 302, and multiple shaft groups. Each shaft group is provided with a rotating shaft 101. The shaft groups include a first shaft group 303, a second shaft group 304, a third shaft group 305, and a fourth shaft group 306. The first end of the first link 301 is rotatably connected to the first component through the first shaft group 303. The second end of the first link 301 is rotatably connected to the first end of the second link 302 through the second shaft group 304. The second end of the second link 302 is rotatably connected to the third component through the third shaft group 305. The linear actuator 307 is rotatably connected to the second link 302 through the fourth shaft group 306. The fourth shaft group 306 is offset from the second shaft group 304.

[0055] The joint assembly described above sets the second axis group 304 and the fourth axis group 306 separately. Since there is a certain distance between the second axis group 304 and the fourth axis group 306, when the linear actuator 307 extends and retracts and acts on the fourth axis group 306, it has its own rotational torque. Compared with the linear actuator 307 acting directly on the first axis group 303, it reduces the power required for the linear actuator 307 to drive the relative rotation of the first and second components, thus reducing the manufacturing cost of the humanoid robot using this joint assembly.

[0056] Linear actuators are not limited to electric push rods composed of planetary ball screws and torque motors. Compared with other types of linear actuators, they have better transmission accuracy, greater rigidity and load-bearing capacity, and can output greater push and pull forces, i.e., a high torque-to-thrust conversion ratio. They can obtain greater output power through the rated speed of the torque motor, making them very suitable for use as actuators for humanoid robots.

[0057] For ease of description, the components connected in a shaft group are defined as connected parts. For example, the first link, the second link, the linear actuator connected to the second link, the first component, and the second component are all connected parts. Specifically, the connected parts in the same shaft group include the first connected part 201 and the second connected part, as shown in the reference. Figure 1 As shown, a first mounting plate and a second mounting plate are spaced apart on the first connected member 201. The first mounting plate and the second mounting plate have coaxial shaft assembly holes. The second connected member is located between the first mounting plate and the second mounting plate, and the second connected member also has shaft assembly holes. The rotating shaft 101 in the corresponding shaft group passes through the first mounting plate, the second connected member and the second mounting plate, thereby realizing the rotational connection between the first connected member 201 and the second connected member. This arrangement can reduce the space occupied by the first connected member 201 and the second connected member, which is beneficial to improving the integration of the joint assembly.

[0058] For example, the second connecting rod, as the first connected member 201, is configured as Y-shaped, with a first mounting plate and a second mounting plate spaced apart at its first end. The first connecting rod, as the second connected member, has its second end located between the first mounting plate and the second mounting plate and connected by a rotating shaft 101 passing through the first mounting plate and the second mounting plate in the second shaft group.

[0059] refer to Figures 3-7 As shown, for ease of maintenance, each shaft assembly (including but not limited to the first, second, third, and fourth shaft assemblies) is detachably connected to its corresponding connected component. During maintenance, simply removing the shaft assembly allows separation of the two connected components, reducing maintenance costs. Furthermore, to prevent the shaft assembly from detaching from its corresponding connected component during normal use, the joint assembly also includes a locking mechanism connected to the shaft assembly to axially limit the shaft assembly to the connected component.

[0060] In one embodiment, the rotating shaft 101 is a T-shaped rotating shaft 101, and the locking element is a bushing 102, which is fixedly sleeved on the end of the rotating shaft 101 away from the head of the rotating shaft 101. In other embodiments, the locking element may also be a cotter pin.

[0061] Given that the locking component uses a bushing 102, which is fixed to the rotating shaft 101 by a fastening screw 104, it is understandable that during the movement of the joint assembly, vibration and the impact of forward and reverse rotation will cause loosening between the fastening screw 104 and the rotating shaft 101. (Refer to...) Figure 5 As shown, in order to prevent the bushing 102 from loosening between the bushing 102 and the rotating shaft 101 due to the rotation of the rotating shaft 101, the head of the rotating shaft 101 is set to be non-circular, for example, elliptical, and the first mounting hole corresponding to the head of the rotating shaft 101 is set to be a countersunk hole adapted to the shape of the head of the rotating shaft 101.

[0062] Further, refer to Figure 6 As shown, the bushing 102 is also non-circular, and the second mounting hole of the bushing 102 is a countersunk hole adapted to the shape of the bushing 102. This allows the bushing 102 to simultaneously limit the circumferential movement of both ends of the rotating shaft 101 along its axial direction, further improving the stability of the shaft assembly on the connected parts. It is understandable that compared to the threaded connection between the bushing 102 and the rotating shaft 101, the fastening screw 104 reduces the assembly difficulty of the bushing 102 and avoids mismatch between the assembly direction of the bushing 102 and the countersunk hole direction. During assembly, the shaft assembly is first assembled onto the connected parts, and the head of the rotating shaft 101 is recessed into the first mounting hole. Then, the direction of the bushing 102 is adjusted, and the bushing 102 is fitted onto the rotating shaft 101 and recessed into the second mounting hole. Finally, the bushing 102 is fixed to the rotating shaft 101 using the fastening screw 104.

[0063] More specifically, in order to further reduce the assembly difficulty of the shaft 101 and the bushing 102, the head of the shaft 101 is provided with a slotted groove or a cross-shaped groove to facilitate the application of force by auxiliary tools such as screwdrivers, while the outer circumferential surface of the bushing 102 is provided with force-applying grooves on both sides to facilitate the application of force.

[0064] refer to Figure 4 As shown, in order to reduce the friction between the shaft assembly and the connected parts and improve the service life of the joint assembly, the shaft assembly also includes rolling bearings 103. Both ends of the connected parts are provided with bearing mounting holes coaxial with the shaft mounting holes. Rolling bearings 103 are installed in both bearing mounting holes to improve the support strength and stability of the connected parts that are rotatably connected to the rotating shaft 101.

[0065] Continue to refer to Figure 4 As shown, in order to further reduce assembly difficulty, prevent axial movement of the rolling bearing 103, thereby improving accuracy and service life of the rolling bearing 103, the shaft assembly also includes a spacer 105. The spacer 105 is disposed between two rolling bearings 103 located on the same rotating shaft 101 and abuts against the two rolling bearings 103. By controlling the length tolerance of the spacer 105, the rolling bearing 103 can be pre-tightened by the sleeve cooperating with the elbow shoulder on the rotating shaft 101.

[0066] An embodiment of this utility model also provides a humanoid robot, including a main body structure and a leg structure. The leg structure is connected to the lower part of the main body structure, and the aforementioned joint assembly can be used in either the main body structure or the leg structure. Since the humanoid robot includes the aforementioned joint assembly and has the same effect as the joint assembly, it will not be described in detail here.

[0067] This utility model also proposes a leg structure, including a rotating support 1, a thigh support 2, a lower leg support 3, a foot 30, a hip joint assembly 4, a knee joint assembly 5, and an ankle joint assembly 6. The rotating support 1 is used to connect the main structure of the humanoid robot. The thigh support 2 is rotatably connected to the rotating support 1 via a fifth axis group 7. The hip joint assembly 4 is also connected between the rotating support 1 and the thigh support 2, and is used to control the relative rotation between the thigh support 2 and the rotating support 1. The thigh support 2 is rotatably connected to the lower leg support 3 via a sixth axis group 8. The knee joint assembly 5 is also connected between the thigh support 2 and the lower leg support 3, and is used to control the relative rotation between the thigh support 2 and the lower leg support 3. The lower leg support 3 is rotatably connected to the foot 30. The ankle joint assembly 6 is also connected between the thigh support 2 and the foot 30, and is used to control the relative rotation between the thigh support 2 and the foot 30. The hip joint assembly 4 includes a hip joint linear actuator, a hip joint first link, a hip joint second link, and multiple hip joint axis assemblies. The knee joint assembly 5 includes a knee joint linear actuator, a knee joint first link, a knee joint second link, and multiple knee joint axis assemblies. Both the hip joint assembly 4 and the knee joint assembly 5 can adopt the aforementioned joint assembly. Specifically, the knee joint linear actuator and the hip joint linear actuator are both linear actuators within the joint assembly; the hip joint first link and the knee joint first link are both first links within the joint assembly; and the hip joint second link and the hip joint second link are both second links within the joint assembly.

[0068] refer to Figure 1 and Figure 2 As shown, both the hip joint linear actuator and the knee joint linear actuator are mounted on the thigh support 2. The fixed end of the hip joint linear actuator is connected to the thigh support 2 via the seventh axis group 9, and the fixed end of the knee joint linear actuator is connected to the thigh support 2 via the eighth axis group 10.

[0069] For the hip joint assembly 4, the first component is the rotary support 1 and the second component is the thigh support 2. The first link of the hip joint is connected to the rotary support 1, and the second link of the hip joint is connected to the thigh support 2. The hip joint linear actuator pushes the second link of the hip joint to rotate by extending and retracting. The second link of the hip joint rotates relative to the thigh support 2, while the first link of the hip joint rotates relative to the rotary support 1, thereby pushing the thigh support 2 to rotate relative to the rotary support 1, realizing the pitching movement of the thigh support 2.

[0070] For the knee joint assembly 5, the first component is the lower leg support 3, and the second component is the thigh support 2. The first link of the knee joint is connected to the lower leg support 3, and the second link of the knee joint is connected to the lower leg support 3. The knee joint linear actuator pushes the second link of the knee joint to rotate by extending and retracting. The second link of the knee joint rotates relative to the thigh support 2, while the first link of the knee joint rotates relative to the lower leg support 3, thereby pushing the lower leg support 3 to rotate relative to the thigh support 2, realizing the pitching movement of the lower leg support 3.

[0071] Specifically, the thigh support 2 includes a left leg plate 21 and a right leg plate 22 spaced apart. The hip joint assembly 4 and the knee joint assembly 5 are both positioned between the left leg plate 21 and the right leg plate 22 to maximize space utilization and improve aesthetics. Both the left leg plate 21 and the right leg plate 22 have shaft assembly holes for mounting the third shaft group, the fifth shaft group 7, the seventh shaft group 9, and the eighth shaft group 10. More specifically, the left leg plate 21 and the right leg plate 22 are connected as a single unit by a crossbeam 23 to improve the coaxiality of the shaft assembly holes corresponding to the same shaft group on the left and right leg plates 21 and 22, reducing the difficulty of shaft assembly installation and simultaneously improving the structural strength of the thigh support 2. It should be noted that "left and right" here refers to the positional relationship when the left and right sides of the human body are used as a reference. For example, the hip joint assembly 4 is positioned rearward, and the knee joint assembly 5 is positioned in front to prevent mutual interference.

[0072] The aforementioned fifth shaft group 7, seventh shaft group 9, and eighth shaft group 10 can all adopt the structure of shaft groups in a joint assembly. Specifically, the rotating shaft 101 in the fifth shaft group 7 is equipped with two rolling bearings 103, which are axially limited by bushings 102. Both the rotating shaft 101 and the bushings 102 are non-circular, and the shape of the corresponding shaft mounting hole is adapted to the shape of the head of the rotating shaft 101 and the bushing 102. It is worth emphasizing that, according to reference... Figure 10 , Figure 11 as well as Figure 14 As shown, in order to increase the swing amplitude of the lower leg support 3, the sixth axis group 8 includes two coaxially spaced rotating shafts 101, and the end of the lower leg support 3 connected to the thigh support 2 is set as Y-shaped, with shaft mounting holes on both the left and right sides. One rotating shaft 101 passes through the shaft mounting hole on the left side of the lower leg support 3 to connect to the left leg plate 21, and the other rotating shaft 101 passes through the shaft mounting hole on the right side of the lower leg support 3 to connect to the right leg plate 22. When the lower leg support 3 swings backward, it can avoid interference between the sixth axis group 8 and the second link in the knee joint assembly 5, thereby increasing the swing amplitude of the lower leg support 3.

[0073] Specifically, the sixth shaft assembly 8 also includes a rolling bearing 103 sleeved on the rotating shaft 101, a fastening screw 104 for fixing the rotating shaft 101 to the thigh support 2, a shaft retaining ring 107, and a bearing retaining ring 106. Both the shaft retaining ring 107 and the bearing retaining ring 106 are sleeved on the rotating shaft 101, with the bearing retaining ring 106 abutting against the side of the calf support 3 facing the thigh support 2. The shaft retaining ring 107 is located on the side of the rolling bearing 103 away from the retaining ring and is fixedly connected to the rotating shaft 101 by the fastening screw 104. To prevent the rotating shaft 101 from rotating relative to the calf support 3, the rotating shaft 101 is also T-shaped, and its head is non-circular. The shaft mounting hole of the thigh support 2 corresponding to the rotating shaft 101 is a countersunk hole adapted to the shape of the head of the rotating shaft 101.

[0074] refer to Figure 16 and Figure 17 As shown, the calf support 3 is connected to the foot 30 via a rotary cross shaft 20. The rotary cross shaft 20 includes a cross shaft support 230, a ninth axis group 210, and a tenth axis group 220. The cross shaft support 230 is fixed to the foot 30. The ninth axis group 210 has a rotating shaft 101 that passes through the cross shaft support 230 in the front-to-back direction. The tenth axis group 220 has a rotating shaft 101 that passes through the cross shaft support 230 in the left-to-right direction. That is, the rotating shaft 101 in the ninth axis group 210 and the rotating shaft 101 in the tenth axis group 220 are perpendicular to each other, so that the foot 30 can perform lateral and pitching movements relative to the calf support 3. Based on this, the ankle joint assembly 6 includes two linear actuators. The two linear actuators are arranged left and right, and the fixed ends of the two linear actuators are rotatably connected to the calf support 3. The output ends of the two linear actuators are rotatably connected to the foot 30.

[0075] When the two linear actuators extend and retract synchronously, they can drive the foot 30 to perform pitching motion relative to the lower leg support 3; when the two linear actuators extend and retract in opposite directions, they can drive the foot 30 to perform rolling motion, i.e., lateral swinging motion, relative to the lower leg support 3. The arrangement of two linear actuators in the ankle joint assembly 6 can provide sufficient power for the movement of the foot 30 relative to the lower leg support 3, which is more conducive to the movement and walking of the humanoid robot.

[0076] Continue to refer to Figure 15 As shown, in one embodiment, the ninth axis group 210 and the tenth axis group 220 are staggered in the height direction. Specifically, the ninth axis group 210 is located below the tenth axis group 220. The lower leg support 3 is connected to the rotary cross axis 20 through the rotating shaft 101 in the tenth axis group 220, and the foot 30 is connected to the rotary cross axis 20 through the rotating shaft 101 in the ninth axis group 210. This avoids interference with the tenth axis group 220 when rotating around the rotating shaft 101 in the ninth axis group 210, thereby increasing the range of motion.

[0077] To improve the stability of the rotating shaft 101 in the ninth shaft group 210 and the rotating shaft 101 in the tenth shaft group 220, the ninth shaft group 210 and the tenth shaft group 220 may also adopt a similar structure to the shaft group in the joint assembly, which will not be described in detail here.

[0078] refer to Figures 15-17 As shown, the foot 30 is rotatably connected to the output end of the linear actuator via the eleventh axis group. The rotating shaft 101 in the eleventh axis group is parallel to the tenth axis group 220, thus ensuring balanced force on both sides when the ankle joint assembly 6 pushes the rotating shaft 101 in the eleventh axis group to rotate. The fixed ends of the two linear actuators in the ankle joint assembly 6 are rotatably connected to the lower leg support 3 via the twelfth axis group.

[0079] To meet the requirements of two rotational degrees of freedom between the foot 30 and the lower leg support 3, both the eleventh axis group and the twelfth axis group include joint bearings 108.

[0080] Understandably, the joint bearing 108 has three rotational degrees of freedom, but in reality, the foot 30 and the lower leg support 3 only require two rotational degrees of freedom. To improve the stability of the ankle joint assembly 6 and prevent it from wobbling, the joint bearing 108 connected to the fixed end and / or output end of the linear actuator in the ankle joint assembly 6 is provided with limiting protrusions 109 spaced back and forth. The rotating shaft 101 in the twelfth axis group is located between the two limiting protrusions 109 and on the line connecting the two limiting protrusions 109. For example, the limiting protrusions 109 are set to be arc-shaped.

[0081] Undoubtedly, the initial length of the linear actuator in the ankle joint assembly 6 is fixed during installation. To ensure a larger range of motion for the foot 30 relative to the lower leg support 3, the joint bearings 108 at both ends of the linear actuator in the ankle joint assembly 6 need to be parallel, as shown in the reference. Figure 17 As shown, to ensure both the installation angle and the installation distance, the output end and / or fixed end of the linear actuator in the ankle joint assembly 6 are connected to the joint bearing 108 via a double-rotating screw, thereby adjusting the installation distance and installation angle. Specifically, to improve installation reliability, a self-locking nut is fitted onto the double-rotating screw.

[0082] refer to Figure 18 As shown, the foot 30 includes a foot shell 320, an ankle support 310, and a six-dimensional force sensor 330. The ankle support 310 is disposed inside the foot shell 320, and the rotary cross shaft 20 is disposed in the middle of the ankle support 310. At the same time, a shaft assembly mounting seat for connecting the eleventh axis group is also provided at the rear of the ankle support 310. The six-dimensional force sensor 330 is disposed on the ankle support 310 and the foot shell 320 to provide the most comprehensive force information, thereby improving control accuracy and agility.

[0083] Specifically, the foot shell 320 includes the shell body, the foot, and the cushioning plate. The foot is located at the bottom of the shell body and forms an installation space to accommodate the ankle support 310. The foot can be either a flat foot or a foot with an arch, without any specific restrictions. The cushioning plate is located at the bottom of the foot and can be made of solid rubber or inflatable rubber to provide shock absorption.

[0084] An embodiment of this utility model also proposes a humanoid robot, including a main body structure and a leg structure, wherein the leg structure is connected to the lower part of the main body structure and adopts the leg structure as described above.

[0085] Since humanoid robots include leg structures and have the same effects as leg structures, they will not be elaborated on here.

[0086] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A joint assembly arranged between first and second members which are rotatably connected, characterised in that, The joint assembly includes: The first link (301) has its first end rotatably connected to the first component via the first shaft assembly (303); The second link (302) has its first end rotatably connected to the second end of the first link (301) via a second shaft assembly (304), and its second end rotatably connected to the second component via a third shaft assembly (305). A linear actuator (307) is rotatably connected to the second connecting rod (302) via a fourth shaft group (306), and the fourth shaft group (306) is offset from the first shaft group (303).

2. A leg structure comprising a rotating support (1), a thigh support (2), a calf support (3), a hip joint assembly (4), a knee joint assembly (5), a foot (30), and an ankle joint assembly (6), wherein the thigh support (2) is rotatably connected to the rotating support (1) via a fifth axis group (7), the hip joint assembly (4) is connected to the rotating support (1) and the thigh support (2) to control their relative rotation, the thigh support (2) is rotatably connected to the calf support (3) via a sixth axis group (8), the knee joint assembly (5) is connected to the thigh support (2) and the calf support (3) to control their relative rotation, the foot (30) is rotatably connected to the calf support (3), and the ankle joint assembly (6) is connected to the foot (30) and the calf support (3) to control their rotation, characterized in that, The hip joint assembly (4) and / or the knee joint assembly (5) adopt the joint assembly of claim 1.

3. The leg structure of claim 2, wherein, The knee joint assembly (5) includes a first knee joint link, a second knee joint link, and a knee joint linear actuator. The first knee joint link is rotatably connected to the lower leg support (3), and the second knee joint link is rotatably connected to the thigh support (2). The fixed end of the knee joint linear actuator is connected to the thigh support (2) through an eighth axis group (10). The knee joint linear actuator controls the relative rotation of the second knee joint link and the first knee joint link. The hip joint assembly (4) includes a first hip joint link, a second hip joint link, and a hip joint linear actuator. The first hip joint link is rotatably connected to the rotary support (1), the second hip joint link is rotatably connected to the thigh support (2), and the fixed end of the hip joint linear actuator is connected to the thigh support (2) through a seventh axis group (9).

4. The leg structure of claim 3, wherein The thigh support (2) is integrated into one unit. The thigh support (2) includes a left leg plate (21) and a right leg plate (22) that are spaced apart. The hip joint assembly (4) and the knee joint assembly (5) are both located between the left leg plate (21) and the right leg plate (22).

5. The leg structure of claim 4, wherein, The sixth shaft group (8) includes two coaxially spaced rotating shafts (101). The end of the calf support (3) connected to the thigh support (2) is Y-shaped and has shaft assembly holes on both the left and right sides. One of the rotating shafts (101) passes through the shaft assembly hole on the left side of the calf support (3) and connects to the left leg plate (21). The other rotating shaft (101) passes through the shaft assembly hole on the right side of the calf support (3) and connects to the right leg plate (22).

6. The leg structure of claim 3, wherein The lower leg support (3) is connected to the foot (30) via a rotary cross shaft (20). The rotary cross shaft (20) includes a ninth shaft group (210) and a tenth shaft group (220). Both the ninth shaft group (210) and the tenth shaft group (220) are provided with a rotating shaft (101). The rotating shaft (101) in the ninth shaft group (210) extends in the front-back direction, and the rotating shaft (101) in the tenth shaft group (220) extends in the left-right direction.

7. The leg structure of claim 6, wherein The ankle joint assembly (6) includes two linear actuators. The ankle joint assembly (6) also includes an eleventh axis group and a twelfth axis group. The fixed ends of the two linear actuators are rotatably connected to the lower leg support (3) through the eleventh axis group. The output ends of the two linear actuators are rotatably connected to the foot (30) through the twelfth axis group. The eleventh axis group and the twelfth axis group each have a rotating shaft (101) and a joint bearing (108) sleeved on the rotating shaft (101).

8. The leg structure of claim 7, wherein, In the ankle joint assembly (6), among the two linear actuators, at least one of the two joint bearings (108) located at both ends of the same linear actuator has a limiting protrusion (109) spaced apart from the front and back, and the line connecting the two limiting protrusions (109) passes through the shaft (101) corresponding to the joint bearing (108).

9. The leg structure of claim 6, wherein, In the first shaft group, the second shaft group, the third shaft group, the fourth shaft group, the eighth shaft group (10), the ninth shaft group (210), and the tenth shaft group (220), at least one shaft group is connected to a first connected member (201) and a second connected member. The first connected member (201) is provided with a first mounting plate and a second mounting plate at intervals. The second connected member is located between the first mounting plate and the second mounting plate. The rotating shaft (101) in at least one shaft group is detachably connected to the first connected member (201) and the second connected member. The two ends of the rotating shaft (101) of the shaft group are respectively connected to the first mounting plate and the second mounting plate.

10. The leg structure of claim 9, wherein, The rotating shaft (101) detachably connected to the first connected member (201) and the second connected member is configured in a T-shape. The shaft assembly also includes a bushing (102), which is fixed to the tail of the rotating shaft (101) by a fastening screw (104).

11. The leg structure of claim 10, wherein, The head of the rotating shaft (101) is non-circular, and the first mounting plate has a countersunk hole for circumferentially limiting the rotating shaft (101); and / or, the bushing (102) is non-circular, and the second mounting plate has a countersunk hole for circumferentially limiting the bushing (102).

12. The leg structure of claim 11, wherein, The shaft assembly also includes rolling bearings (103), and the second connected member has bearing mounting holes for mounting the rolling bearings (103) at both axial ends, and the rolling bearings (103) are mounted in the bearing mounting holes.

13. The leg structure of claim 12, wherein, The shaft assembly also includes a spacer (105), which is disposed between two rolling bearings (103) on the same rotating shaft (101) and abuts against both rolling bearings (103). The rolling bearing (103) near the head of the rotating shaft (101) abuts against a shoulder provided on the rotating shaft (101), and the rolling bearing (103) near the tail of the rotating shaft (101) abuts against the bushing (102).

14. The leg structure of claim 7, wherein, A double-rotating screw is provided between the fixed end of the linear actuator in the ankle joint assembly (6) and the joint bearing (108) of the eleventh axis group, and / or, the double-rotating screw is provided between the output end of the linear actuator in the ankle joint assembly (6) and the joint bearing (108) of the twelfth axis group.

15. The leg structure of claim 2, wherein, The foot (30) has a built-in six-dimensional force sensor (330).

16. A humanoid robot, characterized by The humanoid robot includes the leg structure as described in any one of claims 2-15.

17. A humanoid robot, characterized by The humanoid robot includes the joint assembly as described in claim 1.

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