Humanoid robot leg mechanism and robot

Abstract

The invention provides a humanoid robot leg mechanism and a robot, and relates to the field of humanoid robots, the humanoid robot leg mechanism comprises a shank skeleton, a thigh skeleton and a foot, and is equipped with a first power mechanism and a second power mechanism. The first power mechanism is located in the thigh skeleton, drives the shank skeleton to rotate around the knee joint rotating shaft through a first motor and comprises a first driving wheel, a first driven wheel and a first transmission rope. The two second power mechanisms are arranged on the left side and the right side of the thigh skeleton respectively, drive the feet to move around the naked joint assembly and comprise second motors, second driving wheels, second driven wheels, second transmission ropes and connecting rods, and the connecting rods are connected with the second driving wheels and the feet. The power mechanism is concentrated on the thigh skeleton, so that the inertia of the legs is effectively reduced, and the movement flexibility of the robot is improved. Meanwhile, the space occupied by the leg structure is reduced through the integrated power transmission system, the bloated appearance is avoided, and the attractiveness is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of humanoid robots, and in particular to a humanoid robot leg mechanism and a robot. Background Art

[0002] Humanoid robots, also known as bionic humans, are robots designed to imitate human appearance and behavior, especially those with similar bodies to humans. Humanoid robots can assist or even replace humans in completing dangerous, heavy, and complex tasks, improve work efficiency and quality, and are widely used in many industries such as medicine, military, education, production and life. Among them, the leg mechanism is an important component of humanoid robots, which directly determines the stability and flexibility of humanoid robots. Generally, the leg mechanism of a humanoid robot includes corresponding leg joints such as hip joints, knee joints, and ankle joints. The various leg joints cooperate with each other to complete walking movements similar to human movements.

[0003] However, in traditional designs, the leg mechanism has a large inertia problem. Especially in the calf and sole area, the use of multiple joint modules increases the leg inertia, affecting the robot's motion control and dynamic response. Two common design schemes are: 1. The joint module that provides power is directly connected to the leg joint. When this scheme is adopted, the robot's leg inertia is large, especially the calf and sole are usually installed with 2 to 3 joint modules. The inertia of the robot's legs directly affects the dynamic effect. 2. The joint module that provides power is installed above the thigh, and a connecting rod is used to remotely drive the knee joint and ankle. Although this scheme can reduce the inertia of the calf to a certain extent, because the connecting rod occupies a large space and the range of motion of the joint is limited, the entire leg structure appears bloated and the aesthetics are poor. Summary of the invention

[0004] In view of this, the present invention proposes a humanoid robot leg mechanism and a robot, aiming to solve the problems of large inertia and poor aesthetics of the leg mechanism.

[0005] The technical solution of the present invention is achieved in this way:

[0006] In a first aspect, the present invention provides a humanoid robot leg mechanism, comprising a calf frame, a thigh frame and a foot, wherein the lower end of the thigh frame is rotatably connected to the upper end of the calf frame via a knee joint shaft, and the foot is rotatably connected to the lower end of the calf frame via a bare joint assembly, and further comprising:

[0007] The first power mechanism is arranged inside the thigh frame and is used to drive the calf frame to rotate around the knee joint axis, and includes a first driving wheel, a first driven wheel, a first transmission rope and a first motor. The first motor is fixed to the thigh frame, and its output shaft is fixedly connected to the first driving wheel. The first driven wheel is fixed to an end of the calf frame away from the foot. The first driving wheel and the first driven wheel are connected by a first transmission rope.

[0008] The second power mechanism is provided with two groups, which are respectively located on the left and right sides of the thigh frame, and are used to drive the foot to move around the bare joint assembly, including a second driving wheel, a second driven wheel, a second transmission rope, a second motor and a connecting rod. The second motor is fixedly arranged on the thigh frame, and its output shaft is fixedly connected to the second driving wheel arranged on the outside of the thigh frame. The second driven wheel is arranged on the outside of the thigh frame and is rotatably connected to the knee joint shaft. The second driving wheel and the second driven wheel are connected by a second transmission rope. One end of the connecting rod is rotatably connected to the second driving wheel, and the other end is rotatably connected to the foot.

[0009] On the basis of the above technical solution, preferably, the thigh frame includes two thigh supports arranged in parallel at an interval, the two thigh supports are fixedly connected, the upper end of the calf frame is located between the two thigh supports, and is rotatably connected to the lower ends of the two thigh supports through a knee joint pivot, and the first driving wheel is located at the upper part between the two thigh supports.

[0010] On the basis of the above technical solution, preferably, the first power mechanism further includes a tensioning assembly, and the tensioning assembly includes a pressure sensor, a dynamic tensioning wheel and a sliding seat;

[0011] The sliding seat is horizontally movably mounted on the thigh support, and both ends of the dynamic tensioner are rotatably connected to the sliding seat;

[0012] The first end of the first transmission rope is fixed on the first driven wheel, passes through the first driven wheel, the dynamic tension wheel and the first driving wheel in sequence, and then passes through the first driven wheel again, and the second end is fixed on the first driven wheel to form a closed-loop transmission;

[0013] The pressure sensor is arranged between the sliding seat and the thigh support and is used to detect the tension of the first transmission rope.

[0014] On the basis of the above technical solution, preferably, the first power mechanism also includes a fixed tensioner, which is rotatably arranged between the two thigh supports, and is located between the dynamic tensioner and the first driving wheel or the second driving wheel, and the first transmission rope also passes around the fixed tensioner before or after passing around the dynamic tensioner.

[0015] On the basis of the above technical solution, preferably, the thigh frame also includes a limit frame, which is fixedly arranged at the lower ends of the two thigh supports and is located at the front side of the swing path of the calf frame. When the calf frame swings forward around the knee joint axis, the limit frame contacts the calf frame to limit its swing angle.

[0016] On the basis of the above technical solution, preferably, the second driving wheel includes an inner wheel and an outer wheel, the inner wheel is arranged on the outside of the thigh support and is fixedly connected to the output shaft of the second motor, the outer wheel is rotatably arranged on the outside of the inner wheel, the second transmission rope includes an inner transmission rope and an outer transmission rope, the inner transmission rope is transmission-connected between the inner wheel and the second driven wheel, and the two ends of the inner transmission rope are respectively fixedly connected to the inner wheel and the second driven wheel, the outer transmission rope is transmission-connected between the outer wheel and the second driven wheel, and the two ends of the outer transmission rope are respectively fixedly connected to the outer wheel and the second driven wheel, the inner transmission rope and the outer transmission rope are transmission-connected The moving rope is arranged in a mirror image in space relative to the center line of the second driving wheel and the second driven wheel. An anti-loosening device is arranged between the inner wheel and the outer wheel, and the anti-loosening device includes a ratchet, a pawl and a torsion spring. The ratchet is fixedly arranged on the outer side of the inner wheel, and the pawl is rotatably arranged on the inner side of the outer wheel, and the pawl is cooperatively connected with the ratchet. The winding direction of the inner transmission rope on the inner wheel is the same as the direction in which the pawl crosses the ratchet, and the winding direction of the outer transmission rope on the outer wheel is opposite to the direction in which the pawl crosses the ratchet. The torsion spring is arranged at the rotation axis of the inner wheel and the outer wheel, and the tension direction of the torsion spring is the same as the direction in which the pawl crosses the ratchet.

[0017] On the basis of the above technical solution, preferably, the foot includes a sole and a mounting seat fixedly arranged on the upper part of the sole, the lower end of the calf frame is rotatably connected to the mounting seat through a bare joint assembly, the bare joint assembly includes a pitch axis and a roll axis, the axis of the pitch axis extends along the left and right direction of the foot, allowing the foot to flip forward and backward relative to the calf frame, the axis of the roll axis is perpendicular to the pitch axis and extends along the front and back direction of the foot, allowing the foot to flip left and right relative to the calf frame, and both sides of the mounting seat on the front side of the calf frame are provided with connecting parts rotatably connected to the connecting rod.

[0018] On the basis of the above technical solution, preferably, it also includes a hip joint assembly connected to the upper end of the thigh frame, the hip joint assembly includes a base, a first connecting seat, a second connecting seat, a third motor, a fourth motor and a fifth motor, the first connecting seat is arranged on the front side of the base, the third motor is fixedly arranged on the rear side of the base, and is used to drive the first connecting seat to rotate in the vertical direction, the second connecting seat is located below the first connecting seat, the fourth motor is fixedly arranged on the top surface of the first connecting seat, and is used to drive the second connecting seat to rotate horizontally, the thigh frame is located on one side of the second connecting seat, and the fifth motor is fixedly arranged on the other side of the second connecting seat, and is used to drive the thigh frame to swing back and forth.

[0019] In a second aspect, the present invention discloses a robot, comprising the humanoid robot leg mechanism described in the first aspect.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] (1) The humanoid robot leg mechanism disclosed in the present invention can effectively reduce the inertia of the entire leg by concentrating all the power mechanisms on the thigh frame, so that the robot can show higher flexibility in movement. By adopting an integrated power transmission system, most of the power mechanisms and joint components are placed inside or on both sides of the thigh frame, which reduces the space occupied by the leg structure in the traditional design, avoids the bloated appearance of the legs, and also improves the aesthetics.

[0022] (2) Since the leg transmission system needs to achieve multi-degree-of-freedom movement in a relatively compact space, the use of transmission ropes can effectively reduce the volume and weight. In particular, in the structural design of the calf and foot, it can avoid the space occupied by too many mechanical parts. At the same time, the use of transmission ropes can achieve higher flexibility when transmitting torque, thereby improving the overall flexibility and movement efficiency of the robot.

[0023] (3) By setting a dynamic tensioner and a pressure sensor, the first transmission rope passes around the first driving wheel, and the two ends of the first transmission rope pass around the first driven wheel respectively and are fixedly connected to the first driven wheel. In this way, when the first driving wheel drives the first transmission rope to transmit, the two ends of the first transmission rope will drive the first driven wheel to rotate. During the transmission process of the first transmission rope, the dynamic tensioner tensions the first transmission rope to prevent the first transmission rope from slipping on the first driving wheel due to relaxation. The tension of the transmission rope is monitored in real time by the pressure sensor. When the first transmission rope becomes loose, the position of the sliding seat can be adjusted to allow the dynamic tensioner to resume the tensioning operation of the first transmission rope, thereby achieving the demand for motion transmission.

[0024] (4) By setting up a fixed tensioner, the fixed tensioner acts as a fixed fulcrum to disperse the adjustment pressure of the dynamic tensioner, and the transmission path is divided into a dynamic adjustment section (dynamic tensioner) and a fixed support section (fixed tensioner); the double-wheel layout increases the contact angle between the transmission rope and the pulley, reducing the local bending stress concentration. In addition, after adding the fixed tensioner, the transmission path will be smoother, reducing sharp turns, thereby reducing friction and wear between the transmission rope and the pulley.

[0025] (5) By improving the structure of the second power mechanism, adopting the design of inner and outer wheel coordination and the ratchet pawl anti-loosening device, the unidirectional rotation control of the inner and outer wheels and the stable tension of the transmission system are achieved. The mirror image setting of the inner and outer transmission ropes enables the outer transmission rope to be tensioned when the inner wheel rotates clockwise, and the second driven wheel drives the foot to move; when the inner wheel rotates counterclockwise, the second driven wheel is driven counterclockwise by the inner transmission rope, and the reverse action of the outer transmission rope keeps the outer wheel rotating synchronously. The torsion spring in the anti-loosening device can re-tighten the outer transmission rope through the pre-tightening force when the outer transmission rope is loose, ensuring that the system always maintains appropriate tension, improving the reliability of power transmission and the flexibility of the robot's legs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 It is a schematic diagram of the three-dimensional structure of the leg mechanism of the humanoid robot disclosed in the present invention;

[0028] Figure 2 It is a front view of the leg mechanism of the humanoid robot disclosed in the present invention;

[0029] Figure 3 It is a schematic diagram of the assembly structure of the tensioning component and the thigh frame disclosed in the present invention;

[0030] Figure 4 It is a schematic diagram of the assembly structure of the first power mechanism, the thigh frame and the calf frame disclosed in the present invention;

[0031] Figure 5 It is a schematic diagram of the three-dimensional structure of the second power structure disclosed in the present invention;

[0032] Figure 6 It is a schematic diagram of the planar structure of the second power structure disclosed in the present invention;

[0033] Figure 7 for Figure 5 A partial enlarged view of the middle part;

[0034] Figure 8 for Figure 5 A partial enlarged view of point B in the middle;

[0035] Reference numerals:

[0036] 1. calf skeleton; 2. thigh skeleton; 3. foot; 4. knee joint shaft; 5. bare joint assembly; 6. first power mechanism; 7. second power mechanism; 61. first driving wheel; 62. first driven wheel; 63. first transmission rope; 64. first motor; 71. second driving wheel; 72. second driven wheel; 73. second transmission rope; 74. second motor; 75. connecting rod; 21. thigh bracket; 65. tensioning assembly; 651. pressure sensor; 652. dynamic tensioning wheel; 653. sliding seat; 210 , sliding hole; 654, fixed tensioner; 22, limit frame; 711, inner wheel; 712, outer wheel; 731, inner transmission rope; 732, outer transmission rope; 75, anti-loosening device; 751, ratchet; 752, pawl; 753, torsion spring; 31, sole; 32, mounting seat; 51, pitch axis; 52, roll axis; 321, connecting part; 8, hip joint assembly; 81, base; 82, first connecting seat; 83, second connecting seat; 84, third motor; 85, fourth motor; 86, fifth motor. DETAILED DESCRIPTION

[0037] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] like Figure 1 As shown, combined Figure 2-4 The embodiment of the present invention discloses a humanoid robot leg mechanism, including a calf frame 1, a thigh frame 2 and a foot 3, wherein the lower end of the thigh frame 2 is rotatably connected to the upper end of the calf frame 1 through a knee joint shaft 4, and the foot 3 is rotatably connected to the lower end of the calf frame 1 through a bare joint assembly 5. The above structural arrangement ensures the flexibility of the legs and the coordinated movements between the joints, and ensures that the robot can complete gaits and movements like humans.

[0039] In order to realize the movement of the calf skeleton 1 and the foot 3 , the leg mechanism of this embodiment also includes a first power mechanism 6 and a second power mechanism 7 .

[0040] Among them, the first power mechanism 6 is arranged inside the thigh frame 2, and is used to drive the calf frame 1 to rotate around the knee joint axis 4, including a first driving wheel 61, a first driven wheel 62, a first transmission rope 63 and a first motor 64. The first motor 64 is fixed on the thigh frame 2, and its output shaft is fixedly connected to the first driving wheel 61. The first driven wheel 62 is fixed to the end of the calf frame 1 away from the foot 3. The first driving wheel 61 and the first driven wheel 62 are connected through the first transmission rope 63.

[0041] The first power mechanism 6 realizes the transmission of power through the motor drive gear train. The first motor 64 drives the driving wheel through the output shaft, and the driving wheel drives the driven wheel through the transmission rope, thereby driving the rotation of the calf skeleton 1. Being arranged inside the thigh helps to reduce the inertia of the calf part and improve flexibility and stability.

[0042] Since the first power mechanism 6 is located inside the thigh frame 2, compared to the traditional design of installing the power module on the calf, the increase of the calf inertia is avoided, the motion control and dynamic response performance of the robot is improved, and the aesthetics of the leg mechanism is improved.

[0043] The second power mechanism 7 is provided with two groups, which are respectively located on the left and right sides of the thigh skeleton 2, and are used to drive the foot 3 to move around the bare joint assembly 5, including a second driving wheel 71, a second driven wheel 72, a second transmission rope 73, a second motor 74 and a connecting rod 75. The second motor 74 is fixedly set on the thigh skeleton 2, and its output shaft is fixedly connected to the second driving wheel 71 set on the outer side of the thigh skeleton 2. The second driven wheel 72 is set on the outer side of the thigh skeleton 2 and is rotatably connected to the knee joint shaft 4. The second driving wheel 71 and the second driven wheel 72 are connected by the second transmission rope 73. One end of the connecting rod 75 is rotatably connected to the second driving wheel 71, and the other end is rotatably connected to the foot 3.

[0044] By arranging the second motor 74 and the transmission system on the left and right sides of the thigh skeleton 2, the second motor 74 drives the second driving wheel 71 to rotate, and the second driving wheel 71 drives the second driven wheel 72 to rotate around the knee joint shaft 4 through the second transmission rope 73. During the rotation process, the second driving wheel 71 drives the foot 3 to move around the bare joint assembly 5 through the rotation of the connecting rod 75, thereby reducing the complexity of the calf part and making the foot 3 more flexible. By distributing the power device in the thigh, the complex structure and high inertia problems of the calf and foot 3 are avoided, and the movement performance of the robot is improved. In addition, the transmission scheme of the connecting rod 75 reduces the volume occupied by multiple joint modules, making the entire leg structure more concise and compact.

[0045] In addition, it is worth noting that since the leg transmission system needs to achieve multi-degree-of-freedom movement in a relatively compact space, the use of transmission ropes can effectively reduce the volume and weight, especially in the structural design of the calf and foot, which can avoid the space occupied by too many mechanical parts. At the same time, the use of transmission ropes can achieve higher flexibility when transmitting torque, thereby improving the overall flexibility and movement efficiency of the robot.

[0046] The humanoid robot leg mechanism disclosed in the present invention can effectively reduce the inertia of the entire leg by concentrating all the power mechanisms on the thigh frame 2, so that the robot can show higher flexibility in movement. By adopting an integrated power transmission system, most of the power mechanisms and joint components are placed inside or on both sides of the thigh frame 2, which reduces the space occupied by the leg structure in the traditional design, avoids the bloated appearance of the legs, and also improves the aesthetics.

[0047] As some embodiments, the thigh skeleton 2 of this embodiment includes two thigh supports 21 arranged in parallel at an interval, and the two thigh supports 21 are fixedly connected. Thus, there is a certain installation space between the two thigh supports 21, which is convenient for the installation of parts. In this embodiment, the upper end of the calf skeleton 1 is located between the two thigh supports 21, and is rotatably connected to the lower ends of the two thigh supports 21 through the knee joint shaft 4, and the first driving wheel 61 is located at the upper part between the two thigh supports 21.

[0048] Since the upper end of the calf frame 1 is located between the two thigh supports 21, the first driven wheel 62 is also located between the two thigh supports 21. In this way, most of the components of the first power mechanism 6, such as the first driving wheel 61, the first driven wheel 62 and the first transmission rope 63 are all located between the two thigh supports 21, so that the first power mechanism 6 is integrated into the thigh frame 2. On the one hand, the movement inertia of the calf frame 1 is reduced. On the other hand, the integrated setting can make full use of the internal space of the thigh frame 2 to improve the aesthetics of the leg structure.

[0049] In some embodiments, the first transmission rope 63 is a ring-shaped closed steel wire rope or nylon rope, and the first transmission rope 63 is sleeved on the outside of the first driving wheel 61 and the first driven wheel 62. The first driving wheel 61 is driven to rotate by the first motor 64, and then the first driven wheel 62 is driven to rotate by the first transmission rope 63, so as to realize the rotation of the calf frame 1 around the knee joint axis 4. However, the first transmission rope 63 may loosen during the transmission process, thereby causing the first transmission rope 63 and the first driving wheel 61 and the first driven wheel 62 to slip during the transmission process.

[0050] In order to solve the above problems, the present invention adopts the following technical solutions. Figure 3 and 4 As shown, the first power mechanism 6 of this embodiment further includes a tensioning assembly 65 , and the tensioning assembly 65 includes a pressure sensor 651 , a dynamic tensioning wheel 652 and a sliding seat 653 .

[0051] The sliding seat 653 can be installed on the thigh support 21 in a horizontally movable manner, and the two ends of the dynamic tensioner 652 are rotatably connected to the sliding seat 653. In this embodiment, a sliding hole 210 is horizontally opened on the side wall of the thigh support 21, and the sliding seat 653 is slidably set in the sliding hole 210. The sliding seat 653 can be translated in the sliding hole 210 toward the front and back direction of the thigh frame 2. In some embodiments, the sliding seat 653 can be manually adjusted in the sliding hole 210. By adjusting the position of the sliding seat 653, the position of the dynamic tensioner 652 in the front and back direction of the thigh frame 2 is adjusted.

[0052] The first end of the first transmission rope 63 is fixed on the first driven wheel 62, and after passing through the first driven wheel 62, the dynamic tensioning wheel 652 and the first driving wheel 61 in sequence, it passes through the first driven wheel 62 again, and the second end is fixed on the first driven wheel 62 to form a closed-loop transmission. The pressure sensor 651 is arranged between the sliding seat 653 and the thigh support 21, and is used to detect the tension of the first transmission rope 63.

[0053] With the above technical solution, the first transmission rope 63 bypasses the first driving wheel 61, and the two ends of the first transmission rope 63 bypass the first driven wheel 62 respectively and are fixedly connected to the first driven wheel 62. In this way, when the first driving wheel 61 drives the first transmission rope 63 to transmit, the two ends of the first transmission rope 63 will drive the first driven wheel 62 to rotate. During the transmission process of the first transmission rope 63, the dynamic tensioning wheel 652 tensions the first transmission rope 63 to prevent the first transmission rope 63 from slipping with the first driving wheel 61 due to relaxation. The tension of the transmission rope is monitored in real time by the pressure sensor 651. When the first transmission rope 63 is relaxed, the position of the sliding seat 653 can be adjusted to enable the dynamic tensioning wheel 652 to resume the tensioning operation of the first transmission rope 63, thereby realizing the demand for motion transmission.

[0054] As some embodiments, the first power mechanism 6 also includes a fixed tensioner wheel 654, which is rotatably arranged between the two thigh supports 21, and the fixed tensioner wheel 654 is located between the dynamic tensioner wheel 652 and the first driving wheel 61 or the second driving wheel 71, and the first transmission rope 63 also bypasses the fixed tensioner wheel 654 before or after bypassing the dynamic tensioner wheel 652.

[0055] By adopting the above technical solution, the fixed tension wheel 654 is used as a fixed fulcrum to disperse the adjustment pressure of the dynamic tension wheel 652, and the transmission path is divided into a dynamic adjustment section (dynamic tension wheel 652) and a fixed support section (fixed tension wheel 654). The contact angle between the transmission rope and the pulley is increased through the double-wheel layout, and the local bending stress concentration is reduced. In addition, after adding the fixed tension wheel 654, the transmission path will be smoother, and sharp turns will be reduced, thereby reducing the friction and wear between the transmission rope and the pulley.

[0056] The fixed tensioner 654 fixes the base tension of the transmission rope, and the dynamic tensioner 652 fine-tunes and compensates for the tension change through the sliding seat 653. The cooperation of the two wheels reduces the risk of transmission rope slack and maintains the rigidity of the closed-loop transmission.

[0057] As some implementation methods, when the fixed tensioner 654 is located between the dynamic tensioner 652 and the first driving wheel 61 , the transmission path is “first driving wheel 61 → first dynamic tensioner 652 → first fixed tensioner 654 → first driven wheel 62 ”.

[0058] As some other implementations, when the fixed tensioner 654 is located between the dynamic tensioner 652 and the first driven wheel 62 , the transmission path is “first driving wheel 61 → first fixed tensioner 654 → first dynamic tensioner 652 → first driven wheel 62 ”.

[0059] As some embodiments, the thigh skeleton 2 also includes a limit frame 22, which is fixedly disposed at the lower ends of the two thigh supports 21 and is located in front of the swing path of the calf skeleton 1. When the calf skeleton 1 swings forward around the knee joint axis 4, the limit frame 22 contacts the calf skeleton 1 to limit its swing angle.

[0060] By adopting the above technical solution, the limit frame 22 acts as a rigid blocking structure to directly intervene in the forward swing path of the calf skeleton 1, simulating the physiological limitation of the human knee joint (the human calf cannot bend forward), and replacing pure software or sensor control with physical contact to ensure the absolute safety of mechanical movement.

[0061] In this embodiment, in order to realize the movement of the foot 3, the second transmission rope 73 will be in a closed loop shape, and will be connected to the outside of the second driving wheel 71 and the second driven wheel 72. The second motor 74 drives the second driving wheel 71 to rotate, and then the second transmission rope 73 drives the second driven wheel 72 to rotate, so as to realize the rotation of the foot 3. However, the second transmission rope 73 will loosen during the transmission process, thereby causing the second transmission rope 73 and the second driving wheel 71 and the second driven wheel 72 to slip during the transmission process.

[0062] In order to solve the above problems, the present invention adopts the following technical solutions. Figure 5-7 As shown, this embodiment makes structural improvements to the second power mechanism 7. The second driving wheel 71 includes an inner wheel 711 and an outer wheel 712. The inner wheel 711 is arranged on the outside of the thigh support 21 and is fixedly connected to the output shaft of the second motor 74. The rotation of the inner wheel 711 is directly driven by the second motor 74, and the rotation direction of the inner wheel 711 determines the basic action of the drive transmission system.

[0063] The outer wheel 712 is coaxially rotated and arranged on the outside of the inner wheel 711. The second transmission rope 73 includes an inner transmission rope 731 and an outer transmission rope 732. The inner transmission rope 731 is transmission-connected between the inner wheel 711 and the second driven wheel 72, and the two ends of the inner transmission rope 731 are respectively fixedly connected to the inner wheel 711 and the second driven wheel 72. The outer transmission rope 732 is transmission-connected between the outer wheel 712 and the second driven wheel 72, and the two ends of the outer transmission rope 732 are respectively fixedly connected to the outer wheel 712 and the second driven wheel 72. The inner transmission rope 731 and the outer transmission rope 732 are mirror-imaged in space relative to the center line between the second driving wheel 71 and the second driven wheel 72, and an anti-loosening device 75 is arranged between the inner wheel 711 and the outer wheel 712. The anti-loosening device 75 includes a ratchet 751, a pawl 752 and a torsion spring 753. The ratchet 751 is fixedly arranged on the outer side of the inner wheel 711, the pawl 752 is rotatably arranged on the inner side of the outer wheel 712, and the pawl 752 is cooperatively connected with the ratchet 751. The winding direction of the inner transmission rope 731 on the inner wheel 711 is the same as the direction in which the pawl 752 passes over the ratchet 751. The winding direction of the outer transmission rope 732 on the outer wheel 712 is opposite to the direction in which the pawl 752 passes over the ratchet 751. The torsion spring 753 is arranged at the rotation axis of the inner wheel 711 and the outer wheel 712. The tension direction of the torsion spring 753 is the same as the direction in which the pawl 752 passes over the ratchet 751.

[0064] In this embodiment, the outer wheel 712 is coaxially rotatably disposed outside the inner wheel 711, and is controlled by the inner wheel 711 through the cooperation of the ratchet 751 and the pawl 752. The rotation of the outer wheel 712 is closely related to the rotation direction of the inner wheel 711, and the rotation direction of the inner wheel 711 affects the movement of the outer wheel 712 through the linkage of the ratchet 751 and the pawl 752.

[0065] In this embodiment, the ratchet 751 is fixed on the outside of the inner wheel 711, and the pawl 752 is rotatably arranged on the inside of the outer wheel 712 and cooperates with the ratchet 751. The function of the ratchet 751 is to ensure that the rotation between the inner wheel 711 and the outer wheel 712 is unidirectional by cooperating with the pawl 752 to prevent reverse rotation. As some embodiments, the tooth surface of the ratchet 751 cooperates with the pawl 752 so that when the inner wheel 711 rotates clockwise, the outer wheel 712 must also rotate clockwise and cannot be reversed. The function of the pawl 752 is to limit the reverse rotation of the inner wheel 711 and the outer wheel 712, so that the outer wheel 712 will rotate with the inner wheel 711 when the inner wheel 711 rotates clockwise, and when the inner wheel 711 rotates counterclockwise, the outer wheel 712 can remain stationary.

[0066] Torsion spring 753 is located at the rotation axis of inner wheel 711 and outer wheel 712, and ensures that the two wheels rotate in the direction of the transmission rope tensioning through its tension. The effect of torsion spring 753 is to keep its appropriate tension through tensioning transmission rope when the transmission rope is loose, and prevent the transmission rope from being loosened.

[0067] By making the inner transmission rope 731 and the outer transmission rope 732 mirror-imaged in space relative to the center line of the second driving wheel 71 and the second driven wheel 72, it is explained that the winding direction of the inner transmission rope 731 on the inner wheel 711 and the second driven wheel 72 is different from the winding direction of the outer transmission rope 732 on the outer wheel 712 and the second driven wheel 72. In this embodiment, the winding direction of the inner transmission rope 731 on the inner wheel 711 is the same as the direction in which the pawl 752 crosses the ratchet 751, and the winding direction of the outer transmission rope 732 on the outer wheel 712 is opposite to the direction in which the pawl 752 crosses the ratchet 751. With this arrangement, the inner transmission rope 731 and the outer transmission rope 732 can be tightened under different rotation directions of different inner wheels.

[0068] Specifically, when the inner wheel 711 rotates clockwise, the meshing of the ratchet 751 and the pawl 752 will cause the outer wheel 712 to rotate clockwise. Since the winding direction of the inner transmission rope 731 on the inner wheel 711 is the same as the direction in which the pawl 752 passes over the ratchet 751, at this time, the tension of the inner transmission rope 731 on the inner wheel 711 is reduced and relaxation occurs, and the outer wheel 712 rotates clockwise with the inner wheel 711. Since the winding direction of the outer transmission rope 732 on the outer wheel 712 is opposite to the direction in which the pawl 752 passes over the ratchet 751, the outer transmission rope 732 is tightened between the outer wheel 712 and the second driven wheel 72, and the second driven wheel 72 rotates clockwise driven by the outer transmission rope 732. As the second driven wheel 72 rotates clockwise, it will wrap around the inner transmission rope 731, thereby tightening the inner transmission rope 731 on the inner wheel 711. Since the inner wheel 711 and the outer wheel 712 rotate clockwise synchronously at this time, the torsion spring 753 does not generate tension between the two.

[0069] When the inner wheel 711 rotates counterclockwise, the ratchet 751 will pass the pawl 752, causing the outer wheel 712 to not rotate with the inner wheel 711. However, since the winding direction of the inner transmission rope 731 on the inner wheel 711 is the same as the direction in which the pawl 752 passes over the ratchet 751, at this time, the inner transmission rope 731 is tensioned, and the inner transmission rope 731 drives the second driven wheel 72 to rotate counterclockwise. When the second driven wheel 72 rotates counterclockwise, it will apply a counterclockwise rotational force to the outer wheel 712 through the outer transmission rope 732. At this time, if the outer transmission rope 732 is in tension between the outer wheel 712 and the second driven wheel 72, the outer transmission rope 732 will cause the outer wheel 712 and the inner wheel to rotate counterclockwise synchronously. When the outer transmission rope 732 becomes loose during long-term use (due to creeping, its length increases), since the torsion spring 753 initially has a pre-tightening force, its tension will drive the outer wheel 712 to rotate clockwise relative to the inner wheel 711. This clockwise rotation trend acts on the outer transmission rope 732 to re-tighten it.

[0070] By improving the structure of the second power mechanism, adopting the design of inner and outer wheel matching and the ratchet pawl anti-loosening device, the one-way rotation control of the inner and outer wheels and the stable tension of the transmission system are achieved. The mirror image setting of the inner and outer transmission ropes makes it possible that when the inner wheel rotates clockwise, the outer transmission rope is tensioned and the second driven wheel drives the foot to move; when the inner wheel rotates counterclockwise, the second driven wheel is driven counterclockwise by the inner transmission rope, and the reverse action of the outer transmission rope keeps the outer wheel rotating synchronously. The torsion spring in the anti-loosening device can re-tighten the outer transmission rope through the pre-tightening force when the outer transmission rope is loose, ensuring that the system always maintains the appropriate tension, improving the reliability of power transmission and the flexibility of the robot's legs.

[0071] As some embodiments, refer to the attached Figure 8 As shown, the foot 3 includes a sole 31 and a mounting seat 32 fixedly arranged on the upper part of the sole 31. The lower end of the calf frame 1 is rotatably connected to the mounting seat 32 through a bare joint assembly 5. The bare joint assembly 5 includes a pitch axis 51 and a roll axis 52. The axis of the pitch axis 51 extends along the left and right direction of the foot 3, allowing the foot 3 to flip forward and backward relative to the calf frame 1. The axis of the roll axis 52 is perpendicular to the pitch axis 51 and extends along the front and back direction of the foot 3, allowing the foot 3 to flip left and right relative to the calf frame 1. Both sides of the mounting seat 32 on the front side of the calf frame 1 are provided with connecting parts 321 rotatably connected to the connecting rod 75.

[0072] By adopting the above technical solution, through the setting of the pitch axis 51 and the roll axis 52, the entire foot 3 will perform pitch and roll motion relative to the lower end of the calf frame 1. Specifically, when the second driven wheels 72 in the two second power mechanisms 7 rotate in the same direction and speed, the two second driven wheels 72 respectively form a connecting rod 75 mechanism through the connecting rod 75 and the connecting portion 321 on the mounting seat 32. At this time, the entire foot 3 is flipped forward and backward relative to the calf frame 1 through the pitch axis 51 under the action of the connecting rod 75 mechanism. When the second driven wheels 72 in the two second power mechanisms 7 rotate in different directions, the lower ends of the two connecting rods 75 are not at the same height. At this time, the entire foot 3 is flipped left and right relative to the calf frame 1 through the roll axis 52 under the action of the connecting rod 75 mechanism.

[0073] In order to realize the movement of the thigh frame 2, the leg mechanism of this embodiment also includes a hip joint assembly 8 connected to the upper end of the thigh frame 2, and the hip joint assembly 8 includes a base 81, a first connecting seat 82, a second connecting seat 83, a third motor 84, a fourth motor 85 and a fifth motor 86. The first connecting seat 82 is arranged on the front side of the base 81, the third motor 84 is fixedly arranged on the rear side of the base 81, and is used to drive the first connecting seat 82 to rotate in the vertical direction. The second connecting seat 83 is located below the first connecting seat 82, and the fourth motor 85 is fixedly arranged on the top surface of the first connecting seat 82, and is used to drive the second connecting seat 83 to rotate horizontally. The thigh frame 2 is located on one side of the second connecting seat 83, and the fifth motor 86 is fixedly arranged on the other side of the second connecting seat 83, and is used to drive the thigh frame 2 to swing back and forth.

[0074] By driving the first connecting seat 82 to rotate in the vertical direction through the third motor 84, the angle change between the thigh skeleton 2 and the torso can be controlled, so that the entire leg can swing left and right. The fourth motor 85 controls the horizontal rotation of the second connecting seat 83, so that the robot can adjust the angle of the thigh skeleton 2 more accurately. In this way, the robot can adjust the leg angle when turning and rotating to ensure balance during movement. The fifth motor 86 controls the forward and backward swing of the thigh skeleton 2, which is one of the core mechanisms of simulating gait. By adjusting the forward and backward swing, the robot can move forward or backward like a human, showing natural walking movements. This control method makes the robot's gait more flexible and natural, enabling it to walk efficiently in complex environments.

[0075] By setting the hip joint assembly 8, the entire leg can have three degrees of freedom, namely left-right swing, front-back swing, and horizontal swing.

[0076] The present invention also discloses a robot. Since the specific structure of the leg mechanism and its technical effects have been described in detail in the previous text, this application will not repeat them here. The robot provided by the present application is provided with the leg mechanism described in the previous text, so that the inertia of the entire leg can be effectively reduced, and the robot can show higher flexibility in movement. At the same time, most of the power mechanism and joint components are placed inside or on both sides of the thigh frame 2, which reduces the space occupied by the leg structure in the traditional design, avoids the bloated appearance of the leg, and also improves the aesthetics of the robot.

[0077] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A humanoid robot leg mechanism, characterized in that: The invention comprises a calf frame, a thigh frame and a foot, wherein the lower end of the thigh frame is rotatably connected to the upper end of the calf frame through a knee joint shaft, and the foot is rotatably connected to the lower end of the calf frame through a bare joint assembly, and further comprises: The first power mechanism is arranged inside the thigh frame and is used to drive the calf frame to rotate around the knee joint axis, and includes a first driving wheel, a first driven wheel, a first transmission rope and a first motor. The first motor is fixed to the thigh frame, and its output shaft is fixedly connected to the first driving wheel. The first driven wheel is fixed to an end of the calf frame away from the foot. The first driving wheel and the first driven wheel are connected by a first transmission rope. The second power mechanism is provided with two groups, which are respectively located on the left and right sides of the thigh frame, and are used to drive the foot to move around the bare joint assembly, including a second driving wheel, a second driven wheel, a second transmission rope, a second motor and a connecting rod. The second motor is fixedly arranged on the thigh frame, and its output shaft is fixedly connected to the second driving wheel arranged on the outside of the thigh frame. The second driven wheel is arranged on the outside of the thigh frame and is rotatably connected to the knee joint shaft. The second driving wheel and the second driven wheel are connected by a second transmission rope. One end of the connecting rod is rotatably connected to the second driving wheel, and the other end is rotatably connected to the foot.

2. The humanoid robot leg mechanism according to claim 1, characterized in that: The thigh frame includes two thigh supports arranged in parallel with each other, the two thigh supports are fixedly connected, the upper end of the calf frame is located between the two thigh supports, and is rotatably connected to the lower ends of the two thigh supports through a knee joint shaft, and the first driving wheel is located at the upper part between the two thigh supports.

3. The humanoid robot leg mechanism according to claim 2, characterized in that: The first power mechanism further comprises a tensioning assembly, wherein the tensioning assembly comprises a pressure sensor, a dynamic tensioning wheel and a sliding seat; The sliding seat is horizontally movably mounted on the thigh support, and both ends of the dynamic tensioner are rotatably connected to the sliding seat; The first end of the first transmission rope is fixed on the first driven wheel, passes through the first driven wheel, the dynamic tension wheel and the first driving wheel in sequence, and then passes through the first driven wheel again, and the second end is fixed on the first driven wheel to form a closed-loop transmission; The pressure sensor is arranged between the sliding seat and the thigh support and is used to detect the tension of the first transmission rope.

4. The humanoid robot leg mechanism according to claim 3, characterized in that: The first power mechanism also includes a fixed tensioner, which is rotatably arranged between the two thigh supports and located between the dynamic tensioner and the first driving wheel or the second driving wheel. The first transmission rope also passes around the fixed tensioner before or after passing around the dynamic tensioner.

5. The humanoid robot leg mechanism according to claim 2, characterized in that: The thigh frame also includes a limit frame, which is fixedly arranged at the lower ends of the two thigh supports and is located in front of the swing path of the calf frame. When the calf frame swings forward around the knee joint axis, the limit frame contacts the calf frame to limit its swing angle.

6. The humanoid robot leg mechanism according to claim 2, characterized in that: The second driving wheel includes an inner wheel and an outer wheel, the inner wheel is arranged on the outside of the thigh support and is fixedly connected to the output shaft of the second motor, the outer wheel is rotatably arranged on the outside of the inner wheel, the second transmission rope includes an inner transmission rope and an outer transmission rope, the inner transmission rope is transmission-connected between the inner wheel and the second driven wheel, and the two ends of the inner transmission rope are respectively fixedly connected to the inner wheel and the second driven wheel, the outer transmission rope is transmission-connected between the outer wheel and the second driven wheel, and the two ends of the outer transmission rope are respectively fixedly connected to the outer wheel and the second driven wheel, the inner transmission rope and the outer transmission rope are relative to the second main The center lines of the driving wheel and the second driven wheel are arranged in a mirror image in space, and an anti-loosening device is arranged between the inner wheel and the outer wheel, and the anti-loosening device includes a ratchet, a pawl and a torsion spring. The ratchet is fixedly arranged on the outer side of the inner wheel, and the pawl is rotatably arranged on the inner side of the outer wheel, and the pawl is cooperatively connected with the ratchet. The winding direction of the inner transmission rope on the inner wheel is the same as the direction in which the pawl crosses the ratchet, and the winding direction of the outer transmission rope on the outer wheel is opposite to the direction in which the pawl crosses the ratchet. The torsion spring is arranged at the rotation axis of the inner wheel and the outer wheel, and the tension direction of the torsion spring is the same as the direction in which the pawl crosses the ratchet.

7. The humanoid robot leg mechanism according to claim 1, characterized in that: The foot includes a sole and a mounting seat fixedly arranged on the upper part of the sole. The lower end of the calf frame is rotatably connected to the mounting seat through a bare joint assembly. The bare joint assembly includes a pitch axis and a roll axis. The axis of the pitch axis extends along the left and right direction of the foot, allowing the foot to flip forward and backward relative to the calf frame. The axis of the roll axis is perpendicular to the pitch axis and extends along the front and back direction of the foot, allowing the foot to flip left and right relative to the calf frame. Both sides of the mounting seat on the front side of the calf frame are provided with connecting parts rotatably connected to the connecting rod.

8. The humanoid robot leg mechanism according to claim 1, characterized in that: It also includes a hip joint assembly connected to the upper end of the thigh frame, the hip joint assembly includes a base, a first connecting seat, a second connecting seat, a third motor, a fourth motor and a fifth motor, the first connecting seat is arranged on the front side of the base, the third motor is fixedly arranged on the rear side of the base, and is used to drive the first connecting seat to rotate in the vertical direction, the second connecting seat is located below the first connecting seat, the fourth motor is fixedly arranged on the top surface of the first connecting seat, and is used to drive the second connecting seat to rotate horizontally, the thigh frame is located on one side of the second connecting seat, and the fifth motor is fixedly arranged on the other side of the second connecting seat, and is used to drive the thigh frame to swing back and forth.

9. A robot, characterized in that: Comprising the humanoid robot leg mechanism as described in any one of claims 1 to 8.

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