CN112744312B

CN112744312B - Bionic robot and leg structure thereof

Info

Publication number: CN112744312B
Application number: CN202011406626.4A
Authority: CN
Inventors: 高峻峣; 张春雷; 高建程
Original assignee: Beijing Institute of Technology BIT
Current assignee: Beijing Institute of Technology BIT
Priority date: 2020-12-04
Filing date: 2020-12-04
Publication date: 2023-05-30
Anticipated expiration: 2040-12-04
Also published as: CN112744312A

Abstract

The invention provides a bionic robot and a leg structure thereof, comprising thigh legs, shank legs, feet, knee joints and ankle joints, wherein the leg structure also comprises a knee joint driving mechanism and an ankle front and back lifting driving mechanism; the thigh leg is provided with a first accommodating cavity for accommodating the knee joint driving mechanism; the thigh leg is provided with a second accommodating cavity for accommodating the ankle front and back lifting driving mechanism; the knee joint driving mechanism drives the knee joint through the first transmission mechanism so as to drive the rotation of the shank and the leg trunk; the ankle front and back lifting driving mechanism drives the ankle joint through the second transmission mechanism so as to drive the foot to rotate. The thigh leg is provided with two accommodation cavities, so that the driving mechanism of the knee joint and the ankle joint can be moved upwards, the weight of the cantilever at the tail end of the leg of the bionic robot is reduced, the moment of inertia of the knee joint and the ankle joint during rotation can be effectively reduced, the requirement on the torque of a motor is reduced, the structural space of the joint is optimized, the weight of the joint is reduced, and the flexibility and the movement performance of the bionic robot are improved.

Description

Bionic robot and leg structure thereof

Technical Field

The invention relates to the field of bionic robots, in particular to a bionic robot and a leg structure thereof.

Background

The humanoid robot is an advanced development stage of robot technology, and reflects the research and development level of the robot in various aspects such as mechanics, movement, dynamics and the like. The humanoid robot has strong obstacle crossing capability, omnibearing adjustment of moving direction, strong terrain adaptability, good movement flexibility and high bearing capacity, is the best choice in complex operation environment, and has wide application prospect. The leg-foot type robot with larger size has large volume and mass, and the moment of inertia generated by the legs in the walking process is large when the legs are large in mass, so that the influence on the stability of the movement is obvious. Therefore, how to reduce the weight of the legs is one of the focus problems faced by legged robots.

The existing joint support structure of the humanoid leg-foot robot mostly adopts a human body bionic structure style, the joint rotation support adopts a bearing for supporting, and the driving of the joint rotation is generally installed at the joint position. However, the weight of the joint position can be greatly increased by the structure, the leg trunk is equivalent to the cantilever structure, and the weight of the joint is positioned at the tail end of the cantilever, so that the robot has larger moment of inertia in the running process, the load of the robot in the moving process is increased, and the requirements on a motor are more severe.

Disclosure of Invention

In view of the above, embodiments of the present invention provide a bionic robot and a leg structure thereof, which obviate or ameliorate one or more of the disadvantages of the prior art.

The technical scheme of the invention is as follows:

the leg structure of the humanoid robot comprises thigh legs, shank legs, feet, knee joints and ankle joints, and further comprises a knee joint driving mechanism and an ankle front and back lifting driving mechanism; the thigh leg is provided with a first accommodating cavity for accommodating the knee joint driving mechanism; the thigh leg is provided with a second accommodating cavity for accommodating the ankle front and back lifting driving mechanism; the knee joint driving mechanism drives the knee joint through the first transmission mechanism so as to drive the rotation of the shank and the leg trunk; the ankle lifting driving mechanism drives the ankle joint through the second transmission mechanism so as to drive the foot to rotate.

In some embodiments, the leg structure further comprises an ankle swing drive mechanism for driving the foot to swing in and out; the ankle inner and outer swing driving mechanism is arranged at the top of the shank leg, and the position of the ankle inner and outer swing driving mechanism is higher than the axis of the knee joint.

In some embodiments, the lower leg portion has a slot structure in the middle for rotation of the ankle swing drive mechanism.

In some embodiments, the shell of the ankle inner and outer swing driving mechanism is of a partial spherical structure, the groove-shaped structure of the thigh leg is a U-shaped groove, and the top surface of the U-shaped groove is a partial spherical cambered surface.

In some embodiments, one side of the upper portion of the shank has a first connection seat to connect the knee joint and the first transmission mechanism; the first transmission mechanism comprises a first synchronous belt mechanism and a first knee joint shaft, a first flange plate is arranged on the first knee joint shaft, and the first flange plate is connected with the first connecting seat through a harmonic reducer so as to drive the leg to rotate around the knee joint.

In some embodiments, the other side of the upper portion of the shank has a second connection seat opposite the first connection seat; the second transmission mechanism comprises a second synchronous belt mechanism, a second knee joint shaft, a first plate belt disc and at least one first transmission plate belt; the second knee joint shaft is provided with a second flange plate which is fixedly connected with the first plate belt disc through a harmonic reducer so as to drive the first plate belt to rotate around the second knee joint shaft; the middle of the first plate belt disc is provided with an annular concave part perpendicular to the second knee joint shaft, and the first plate belt disc is provided with two mounting holes parallel to the axial direction for mounting two first transmission plate belts; one end of the second transmission plate belt is connected with the first plate belt disc, and the other end of the second transmission plate belt is used for driving the ankle joint to rotate.

In some embodiments, the ankle inner and outer swing drive mechanism comprises a motor, a speed reducer, a second strap reel, and a second drive strap; wherein, motor, reduction gear and second slab band dish are installed in a casing that is the part ball-type.

In some embodiments, the shank is a hollow structure penetrating up and down, and the second driving strap passes through the hollow structure of the shank and is connected to the ankle joint.

In some embodiments, the first receiving cavity and the second receiving cavity are located at an upper portion of the thigh shaft.

According to another aspect of the present invention, there is also provided a biomimetic robot comprising the aforementioned leg structure.

According to the bionic robot and the leg structure thereof, the beneficial effects at least comprise:

the thigh leg is provided with two accommodation cavities, so that the driving mechanism of the knee joint and the ankle joint can be moved upwards, the weight of the cantilever at the tail end of the leg of the bionic robot is reduced, the moment of inertia of the knee joint and the ankle joint during rotation can be effectively reduced, the requirement on the torque of a motor is reduced, the structural space of the joint is optimized, the weight of the joint is reduced, and the flexibility and the movement performance of the bionic robot are improved.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims thereof as well as the appended drawings.

It will be appreciated by those skilled in the art that the objects and advantages that can be achieved with the present invention are not limited to the above-described specific ones, and that the above and other objects that can be achieved with the present invention will be more clearly understood from the following detailed description.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate and together with the description serve to explain the invention. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Corresponding parts in the drawings may be exaggerated, i.e. made larger relative to other parts in an exemplary device actually manufactured according to the present invention, for convenience in showing and describing some parts of the present invention. In the drawings:

fig. 1 is a schematic perspective view of a leg structure of a bionic robot according to an embodiment of the invention.

Fig. 2 is a left side schematic view of a leg structure according to an embodiment of the present invention.

Fig. 3 is a right side schematic view of a leg structure according to an embodiment of the present invention.

Fig. 4 is a schematic perspective view of a thigh trunk according to an embodiment of the present invention.

Fig. 5 is a schematic perspective view of a shank according to an embodiment of the present invention.

Fig. 6 is a schematic diagram of a leg structure cross-sectional structure of a bionic robot according to an embodiment of the invention.

Fig. 7 is a perspective view of a cross-shaft of an ankle joint of a leg structure according to an embodiment of the present invention.

Fig. 8 is a perspective view of an ankle support of an ankle joint of a leg structure according to an embodiment of the present invention.

Fig. 9 is an exploded view of an ankle joint of a leg structure according to an embodiment of the present invention.

Fig. 10 is a perspective view of an ankle joint and a driving mechanism of a leg structure according to an embodiment of the present invention.

FIG. 11 is a schematic view showing a part of the ankle front and rear lift driving mechanism of a leg structure according to an embodiment of the present invention.

Fig. 12 is a schematic view showing a part of the structure of the ankle inner and outer swing driving mechanism of the leg structure according to an embodiment of the present invention.

Fig. 13 is a schematic view illustrating a cross-sectional structure of a leg structure of a bionic robot according to another embodiment of the present invention.

Fig. 14 is an enlarged schematic view of the partial structure of fig. 6.

Detailed Description

The present invention will be described in further detail with reference to the following embodiments and the accompanying drawings, in order to make the objects, technical solutions and advantages of the present invention more apparent. The exemplary embodiments of the present invention and the descriptions thereof are used herein to explain the present invention, but are not intended to limit the invention.

It should be noted here that, in order to avoid obscuring the present invention due to unnecessary details, only structures and/or processing steps closely related to the solution according to the present invention are shown in the drawings, while other details not greatly related to the present invention are omitted.

It should be emphasized that the term "comprises/comprising" when used herein is taken to specify the presence of stated features, elements, steps or components, but does not preclude the presence or addition of one or more other features, elements, steps or components.

It is also noted herein that the term "coupled" may refer to not only a direct connection, but also an indirect connection in which an intermediate is present, unless otherwise specified.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings, the same reference numerals represent the same or similar components, or the same or similar steps.

The invention aims to design a shank connection multiple joint support structure of a bionic robot, and aims to optimize knee and shank joint structures of the robot, reduce rotational inertia when the knee and shank swing, and the shank leg of the structure supports the structures of three joints, namely a knee joint, an ankle outward swing and an ankle forward lifting, so that a driving mechanism of the knee joint and an ankle joint is moved upwards, the weight of a cantilever at the tail end of the shank is reduced, the rotational inertia of the joint during rotation is reduced, thereby reducing the requirement on motor torque, optimizing the joint structure space, reducing the weight of the joint and improving the flexibility and the movement performance of the robot.

The invention provides a leg structure of a humanoid robot, which is used for optimizing a knee joint structure of the humanoid robot and reducing moment of inertia when the knee joint and the lower leg swing.

As shown in fig. 1 to 3, the leg structure of the humanoid robot of the embodiment of the present invention includes a thigh leg 100, a shank leg 200, a foot 300, a knee joint 400, an ankle joint 500, and the like. The leg structure also includes a knee joint drive mechanism 600 and an ankle anterior-posterior lift drive mechanism 700.

As shown in fig. 4, the thigh shank 100 has a first receiving cavity 130 thereon to house a knee joint driving mechanism 600; the thigh shank 100 has a second receiving chamber 140 thereon for receiving the ankle forward and backward lifting driving mechanism 700.

In this embodiment, two receiving cavities are provided in the thigh shank 100 for mounting two drive mechanisms, such as power structures for driving the knee joint in rotation and the ankle joint in swing back and forth, respectively (i.e., the shank in rotation and the knee joint in rotational degrees of freedom in one direction). The two accommodation cavities are optionally arranged at the upper part of the thigh leg 100, the driving mechanisms of the knee joint and the ankle joint are moved upwards, the weight of the cantilever at the tail end of the leg of the bionic robot is reduced, the moment of inertia of the knee joint and the ankle joint during rotation can be effectively reduced, the requirement on the torque of a motor is reduced, the structural space of the joint is optimized, the weight of the joint is reduced, and the flexibility and the movement performance of the bionic robot are improved.

In the above embodiment, the knee joint driving mechanism 600 and the ankle front and rear lifting driving mechanism 700 are respectively installed in two accommodation chambers on the thigh shaft 100, and the two accommodation chambers may be respectively located on the front and rear sides of the thigh shaft, preferably on the same height, and respectively output power from the left and right sides of the thigh shaft, but not limited thereto, the knee joint driving mechanism 600 and the ankle front and rear lifting driving mechanism 700 may be located in the same accommodation chamber, and may be determined according to the size of the driving mechanism or the motor power, the model, and the size of the corresponding decelerator in particular cases.

In the above embodiment, the knee joint driving mechanism 600 drives the knee joint through the first transmission mechanism to drive the rotation motion of the shank 200; the ankle forward and backward lifting driving mechanism 700 drives the ankle joint 500 through a second transmission mechanism to drive the foot 300 to rotate. The knee joint driving mechanism 600 and the ankle front and rear lifting driving mechanism 700 may include a motor and a decelerator connected to an output shaft of the motor, and the motor may be a frameless motor without a housing frame, and may be adapted to a space of the thigh shank accommodating chamber.

In the above-described embodiment, as shown in fig. 2 and 6, the first transmission mechanism may include a first timing belt mechanism and a first knee joint shaft 640. The first timing belt mechanism may be disposed at one side of the thigh, and may include a first driving pulley 610, a first driven pulley 630, and a first timing belt 620. Wherein the first driving pulley 610 is mounted on the power output shaft of the knee joint driving mechanism 600, the first driven pulley 630 is mounted on the first knee joint shaft 640, and the first synchronization belt 620 connects the first driving pulley 610 and the first driven pulley 630 in synchronization. In this embodiment, the first flange 441 is provided at the middle of the first knee joint shaft 640, and the first flange 441 can be fixedly connected with the first connecting seat 210 of the shank through a harmonic reducer, so as to transmit the power of the knee joint driving mechanism 600 to the shank, and complete the rotation of the knee joint or shank, i.e. the walking motion of the bionic robot.

In some embodiments, the leg structure further includes an ankle pendulum drive mechanism 800 fixedly mounted at a top position of the shank 200. Wherein, ankle inner and outer swing driving mechanism 800 is higher than the axis of knee joint 400, and when shank 200 rotates, ankle inner and outer swing driving mechanism 800 and shank 200 rotate reversely and synchronously around the axis of knee joint 400.

According to the leg balancing structure provided by the embodiment of the invention, the leg balancing structure is arranged at the position, above the axis position of the knee joint, of the shank, so that the shank is provided with the hardware structures at two sides of the rotation center of the knee joint, the structures at the two sides are fixedly connected, and the rotation directions are opposite, so that the rotation inertia of the shank at the position of the knee joint is much smaller than that of the shank cantilever structure commonly used in the prior art, and therefore, the requirement on motor torque during walking of the humanoid robot is reduced, the cost is reduced, and the walking endurance of the humanoid robot is improved.

In some embodiments, as shown in fig. 4, the mid-position of the lower half of the thigh shaft 100 has a channel structure 110 for rotation of the ankle swing drive 800. The thigh shank 100 has plate-

like portions

120A and 120B on both sides of the lower portion, respectively, and has holes for receiving the knee joints 400.

In some embodiments, as shown in fig. 5, the top of shank 200 has an annular interface 230 for connection with ankle hoist drive mechanism 800. The upper part 200 of the shank has a first coupling seat 210 at one side thereof and a second coupling seat 220 at the other side thereof opposite to the first coupling seat 210, and the first coupling seat 210 and the second coupling seat 220 are used to couple the knee joint 400 and the thigh shank 100 such that the shank 200 can rotate about the axis of the knee joint 400, thereby realizing the walking motion of the bionic robot.

In some embodiments, as shown in fig. 4, the lower half of the thigh shank 100 has a channel structure 110, the channel structure 110 being formed by sandwiching convex plate-like portions on both sides of the thigh shank. The two plate-shaped portions may be a first plate-shaped portion 120A and a second plate-shaped portion 120B, respectively, to interface with the left and right portions of the knee joint 400, respectively, a first knee joint 400A and a second knee joint 400B, respectively. In this embodiment, both plate-like portions have annular seats for mounting the knee joint 400 and the corresponding portion of the abutting shank. The annular seats of the two plate-shaped portions may have through-hole structures having the same or different diameters to mount the knee joint 400, and the outer periphery of the through-hole structures has a plurality of connection holes for fixing connection distributed circumferentially.

In some embodiments, as shown in fig. 6, knee joint 400 may be coupled to thigh shank 100 and shank 200 via end caps and bearings. For example, the first knee 400A may include a first knee cap 410, a first connection ring 420, a first bearing 430, and the like. One end of the first knee joint end cap 410 is sleeved in the annular seat of the first plate-shaped portion 120A of the thigh shank, and is fixedly connected with the annular seat through a threaded connecting piece, the other end of the first knee joint 400A is installed at the inner side of the thigh shank and is fixedly connected with the first connecting ring 420, and the first bearing 430 is installed in the following manner: the outer ring contacts the inner circumferential surface of the first connection ring 420, and the inner ring contacts the outer circumferential surface of the first connection seat 210 of the shank 200. In this manner, thigh shank 100 and shank 200 may be coupled for relative rotation.

In some embodiments, the first bearing 430 may be a crossed roller bearing, in which the inner ring or the outer ring is in a two-divided structure, the rollers are in a crossed arrangement, and can bear loads in all directions, the bearing clearance can be adjusted, and even if a preload is applied, high-precision rotary motion can be obtained, so that the bearing is suitable for being used as a joint bearing in the field of robots. Other types of bearings may be used for the first bearing 430.

In another embodiment, the second knee joint 400B may take the same composition and configuration as the first knee joint 400A, as well as other configurations. For example, as shown in fig. 6, the second knee 400B may include a second knee cap 460, a second bearing 470, and the like. One end of the second knee cap 460 is fixedly connected, such as screwed or bolted, with the second connecting seat 220 of the shank 200, and the other end of the second knee cap 460 extends inward and is necked down. The outer circumference of the second knee cap 460 is sleeved with a second bearing 470, and the annular seat of the second plate-shaped portion 120B of the thigh trunk 100 can be abutted at the second bearing 470, so that the second plate-shaped portion of the thigh trunk and the shank trunk 200 can be connected in a relatively rotatable manner through the second knee joint 400B. The thigh shank 100 and the shank 200 of the embodiment of the invention are connected and assembled together through the paired bearings of the knee joint 400, so that the rigidity and stability of the shank during rotation can be ensured.

In some embodiments, the thigh shank channel structure 110 is a U-shaped channel with a top surface that is a partial arcuate surface.

In some embodiments, the ankle inner and outer swing driving mechanism 800 is at least partially spherical, and the ankle inner and outer swing driving mechanism 800 is arranged to be partially spherical, so that the center of gravity can be kept centralized, the ankle inner and outer swing driving mechanism 800 can be kept stable in the rotation process, and meanwhile, the space occupied by a motion path is reduced.

In some embodiments, shank 200 may be a hollow structure that extends up and down to reduce the overall weight of the leg.

In some embodiments, the top of shank 200 has an annular interface 230, and the annular interface 230 may secure ankle medial-lateral swing drive mechanism 800 via an end cap and a connector.

As shown in fig. 1, 6, and 7 to 9, the ankle joint 500 according to the embodiment of the present invention is installed between the shank 200 and the foot 300, and the ankle joint 500 may implement two degrees of freedom in rotation to implement a forward lifting motion and a backward swinging motion of the humanoid ankle joint, and the ankle joint 500 may include a cross shaft 510, an ankle support 520, an ankle joint first transmission shaft 530, an ankle joint second transmission shaft 540, and the like.

As shown in fig. 7, the cross shaft 510 includes a first direction shaft 511 and a second direction shaft 512 perpendicular to each other, the first direction shaft 511 is rotatably installed at the lower connection part 240 of the shank 200, and the first direction shaft 511 and the second direction shaft 512 are hollow shafts having through holes. In some embodiments, an upper portion of the first direction shaft 511 adjacent to the second direction shaft 512 has a recess 5111 to expose a through hole of the first direction shaft 511, mount the ankle joint second transmission shaft 540, and the like. The recess 5111 also serves to provide a certain turnover space for the ankle second transmission shaft 540. The ankle joint second transmission shaft is arranged in the cross shaft, is compact in structure, and can meet the ankle joint with the humanoid function in a design space with a small space.

As shown in FIG. 8, the ankle support 520 of the embodiment of the invention is mainly used for connecting with the second direction shaft 512 of the cross shaft 510, so that the ankle support 520 can rotate around the second direction shaft 512 as the axis. The ankle support 520 has a rotation shaft 521, and the rotation shaft 521 is inserted into the through hole of the second direction shaft 512 so that the ankle support 520 can rotate about the second direction shaft 512.

In one embodiment, as shown in fig. 8, 9, and 13, ankle support 520 may include a first post 522, a second post 423, and a base portion 524 supporting both posts. For ease of assembly, the first leg 522 and the base portion 524 may be integrally formed, and the second leg 423 may be fixedly attached to an end of the base portion 524 by a connector (e.g., a screw). The first upright 522 and the second upright 423 are arranged at a certain interval, the second upright 423 is provided with a seat hole for bearing the second direction shaft 512 of the cross shaft 510, the rotating shaft 521 can also be integrally formed with the first upright 522, and the rotating shaft 521 is arranged between the first upright 522 and the second upright 423 and is coaxial with the seat hole of the second upright 423. The middle position of the rotating shaft 521 is provided with a through overturning hole 5211, the direction of the overturning hole 5211 is vertical to the axial direction of the rotating shaft 521, the ankle joint second transmission shaft 540 is inserted into the overturning hole 5211 and fixedly connected with the rotating shaft 521 of the ankle support, and the fixed connection enables the rotating shaft 521 and the ankle joint second transmission shaft 540 to synchronously overturn. The ankle support 520 is arranged in the following manner: the first and second posts 522 and 423 are respectively located at front and rear sides of the leg, and rotatably connected to the second direction shaft 512 of the cross shaft through a rotation shaft 521, so that the ankle joint or the foot can perform the swing motion.

In some embodiments, as shown in FIG. 9, ankle support 520 may further include a top connector 525 disposed between first post 522 and second post 423 for reinforcing the connection.

The first transmission shaft 530 of the ankle joint according to the embodiment of the present invention is fixedly connected to the first direction shaft 511, and the first transmission shaft 530 of the ankle joint is driven by the ankle front and rear elevation driving mechanism 700, so that the first transmission shaft 530 of the ankle joint drives the first direction shaft 511 to rotate, thereby performing the ankle front and rear elevation operation.

The ankle joint according to the embodiment of the present invention may have two degrees of freedom in the rotation direction, and thus is provided with the ankle front and rear lift driving mechanism 700 and the ankle inner and outer swing driving mechanism 800. In order to reduce the weight of the ankle joint portion and reduce the moment of inertia when the ankle joint rotates, the main weight structures of the ankle front and rear lifting driving mechanism 700 and the ankle inner and outer swing driving mechanism 800 can be moved upwards and arranged on the upper parts of the thigh and/or the shank to reduce the requirement on the torque of a motor, optimize the structural design of the whole leg structure, reduce the weight of the ankle joint portion and improve the flexibility of the robot.

In one embodiment, as shown in fig. 3, 6 and 10, the ankle forward and backward lifting driving mechanism 700 may include a motor and a decelerator, and the second transmission mechanism may include a second driving pulley 710, a second driven pulley 730 and a second timing belt 720. Wherein the motor and the decelerator may be installed in the second receiving chamber 140 of the thigh shaft. In order for the motor at the upper portion of the thigh shaft to transmit power to the ankle joint portion, the second transmission mechanism of the ankle front and rear elevation driving mechanism 700 may have a two-stage transmission mechanism, and thus the second transmission mechanism further includes a second knee joint shaft 740, a first strap reel 760, at least one first transmission strap 770, and the like.

The second knee joint shaft 740 is provided with a second flange 741, and the second flange 741 is fixedly connected with the first plate belt disc 760 through a harmonic reducer to drive the first plate belt disc 760 to rotate around the second knee joint shaft 740. In one embodiment, the first reel 760 has an annular recess in the middle perpendicular to the second knee joint axis 740, and the first reel 760 has two mounting holes parallel to the axial direction, which are located in a non-central position on the first reel 760 and symmetrically distributed. The mounting holes are used to mount two first drive plate bands 770 via pivots or pins.

As shown in fig. 11, one end of the first driving plate belt 770 is pivotally connected to the first plate belt reel 760, and the other end is pivotally connected to the ankle joint first driving shaft 530, so that the ankle joint first driving shaft 530 is also driven to synchronously rotate by the first driving plate belt 770 under the condition that the first plate belt reel 760 rotates, thereby realizing the fore-and-aft lifting action of the ankle joint.

For example, as shown in fig. 10, two pin holes 531 are formed at both sides of the first transmission shaft 530 of the ankle joint, respectively, for pivotal connection with the lower end of the first transmission plate belt 770, and a plurality of screw holes 532 or bolt holes are formed at the middle part of the first transmission shaft 530 of the ankle joint, for fixed connection with the screw holes 5112 of the end of the first direction shaft 511 of the cross shaft. As shown in fig. 10, a reinforcing plate 550 is further provided at positions corresponding to the pin shaft holes 531 at the outer sides of the two first driving plate bands 770 to maintain the reliable connection of the driving plate bands to the ankle joint first driving shaft 530.

As shown in fig. 10 and 12, the ankle inner and outer swing driving mechanism 800 of the embodiment of the present invention may include a motor, a decelerator, a motor shaft 810, a second reel 820, and a second transmission belt 830. Wherein the second reel 820 may have the same structure as the first reel 760, and the second reel 820 may be driven by the motor shaft 810 or a decelerator, thereby driving the second driving tape 830 to swing around the center of the second reel 820.

In this embodiment, the motor, the decelerator, the motor shaft 810, the second reel 820, etc. may be disposed in a partially spherical housing, mounted on the top of the shank as a shank weight structure higher than the axis of the knee joint, and rotated in the opposite direction in synchronization with the shank 200 around the axis of the knee joint in the case of rotation of the shank 200. Therefore, the two sides of the rotation center of the knee joint of the shank are provided with the hardware structures, and the rotation directions are opposite, so that the rotation inertia of the shank at the position of the knee joint is much smaller than that of a shank cantilever type structure commonly used in the prior art, and the requirements on motor torque when the humanoid robot walks are reduced.

The second drive plate band 830 may have a similar structure to the first drive plate band 770, and both ends of the two drive plate bands may be arcuately extended in shape to accommodate the rotational path and stress conditions of the plate reels. The first driving plate belt 770 may be disposed at one side of the shank, and the second driving plate belt 830 may be disposed at the inner side of the shank. In addition, the first and

second drive belts

770 and 830 may each be provided with 2 to balance the pulling or pushing force of the drive belts.

In one embodiment, the other ends of the two second driving belts 830 are pivotally connected to two ends of the ankle second driving shaft 540 to drive the second driving shaft 540 to swing. For example, as shown in fig. 12, both ends of the second driving shaft 540 have pin shaft holes for pivotally connecting with the lower end of the second driving plate belt 830.

According to the ankle joint first transmission shaft and the ankle joint second transmission shaft, a double-rocker mechanism transmission mode formed by combining a plate belt disc with a transmission plate belt is innovatively designed, the double-rocker mechanism transmission mode is suitable for a driving mode of ankle joint action, a power structure for driving the ankle joint is moved to the knee joint and the thigh, and the structural design space is optimized.

In one embodiment, the ankle second drive shaft may be coupled to the ankle support shaft 521 via a sleeve structure. As shown in fig. 14, the middle part of the overturning hole 5211 is provided with a first limiting ring 5212, the ankle joint second transmission shaft 540 is provided with two symmetrical second limiting rings 541, and two positioning sleeves 520 are sleeved on the periphery of the ankle joint second transmission shaft 540 and are respectively positioned between the first limiting ring and the second limiting ring.

In another embodiment, the shaft section or sleeve of the ankle second transmission shaft 540 is connected to the turnover hole 5211 of the rotation shaft of the ankle support in a swelling manner. Fastening and power transmission can also be realized through tensioning connection.

According to the ankle joint disclosed by the embodiment of the invention, two rotational degrees of freedom of the ankle joint or the foot can be realized, the multidirectional swinging function at the ankle of a humanoid person is realized by a simpler and innovative design structure, the power structure for driving the ankle joint is moved upwards to the knee joint and the thigh, the structural design space is optimized, the weight of the ankle joint, the knee joint and the whole weight is reduced, and the flexibility and the movement performance of a robot are improved.

In this disclosure, features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with or instead of the features of the other embodiments.

The above description is only of the preferred embodiments of the present invention and is not intended to limit the present invention, and various modifications and variations can be made to the embodiments of the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The leg structure of the humanoid robot comprises thigh legs, shank legs, feet, knee joints and ankle joints, and is characterized by further comprising a knee joint driving mechanism, an ankle front and back lifting driving mechanism and an ankle inner and outer swing driving mechanism for driving the feet to swing inwards and outwards, wherein the ankle inner and outer swing driving mechanism comprises a motor, a speed reducer, a second plate belt disc and a second transmission plate belt;

the upper part of the thigh leg is provided with a first accommodating cavity for accommodating the knee joint driving mechanism;

the upper part of the thigh leg is provided with a second accommodating cavity for accommodating the ankle front and back lifting driving mechanism;

the ankle inner and outer swing driving mechanism is arranged at the top of the shank leg, and the position of the ankle inner and outer swing driving mechanism is higher than the axis of the knee joint, wherein the motor, the speed reducer and the second plate belt disc are arranged in a shell which is in a partial spherical shape and used as a shank counterweight structure;

the knee joint driving mechanism drives the knee joint through the first transmission mechanism so as to drive the rotation of the shank and the leg trunk;

the ankle lifting driving mechanism drives the ankle joint through the second transmission mechanism so as to drive the foot to rotate.

2. The leg structure of the humanoid robot of claim 1, wherein,

the middle position of the lower half part of the thigh leg is provided with a groove structure for the ankle inner and outer swing driving mechanism to rotate.

3. The leg structure of the humanoid robot according to claim 2, wherein the shell of the ankle inner and outer swing driving mechanism is of a partial spherical structure, the groove-shaped structure of the thigh leg is a U-shaped groove, and the top surface of the U-shaped groove is a partial spherical cambered surface.

4. The leg structure of the humanoid robot of claim 1, wherein one side of the upper part of the shank has a first connection seat to connect the knee joint and the first transmission mechanism;

the first transmission mechanism comprises a first synchronous belt mechanism and a first knee joint shaft, a first flange plate is arranged on the first knee joint shaft, and the first flange plate is connected with the first connecting seat through a harmonic reducer so as to drive the leg to rotate around the knee joint.

5. The leg structure of the humanoid robot of claim 4, wherein the other side of the upper portion of the shank has a second connection seat opposite to the first connection seat;

the second transmission mechanism comprises a second synchronous belt mechanism, a second knee joint shaft, a first plate belt disc and at least one first transmission plate belt;

the second knee joint shaft is provided with a second flange plate which is fixedly connected with the first plate belt disc through a harmonic reducer so as to drive the first plate belt to rotate around the second knee joint shaft;

the middle of the first plate belt disc is provided with an annular concave part perpendicular to the second knee joint shaft, and the first plate belt disc is provided with two mounting holes parallel to the axial direction for mounting two first transmission plate belts;

one end of the second transmission plate belt is connected with the first plate belt disc, and the other end of the second transmission plate belt is used for driving the ankle joint to rotate.

6. The leg structure of the humanoid robot of claim 1, wherein the shank is a hollow structure penetrating up and down, and the second driving plate belt penetrates through the hollow structure of the shank and is connected to the ankle joint.

7. A biomimetic robot, characterized in that it comprises a leg structure according to any one of claims 1 to 6.