A humanoid robot leg mechanism and robot

Abstract

The application provides a humanoid robot leg mechanism and a robot, and relates to the field of humanoid robots.The leg mechanism comprises a lower leg skeleton, a thigh skeleton and a foot, and is provided with first and second power mechanisms.The first power mechanism is located in the thigh skeleton and drives the lower leg skeleton to rotate around a knee joint rotating shaft through a first motor, and comprises a first driving wheel, a first driven wheel and a first transmission rope.The second power mechanism has two groups and is arranged on the left and right sides of the thigh skeleton to drive the foot to move around a naked joint assembly, and comprises a second motor, a second driving wheel, a second driven wheel, a second transmission rope and a connecting rod.The connecting rod connects the second driving wheel and the foot.The application effectively reduces the inertia of the leg and improves the motion flexibility of the robot by concentrating the power mechanism in the thigh skeleton.Meanwhile, the integrated power transmission system reduces the space occupied by the leg structure, avoids a bulky appearance and improves the aesthetic appearance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of humanoid robots, and particularly relates to a humanoid robot leg mechanism and a robot. BACKGROUND

[0002] A humanoid robot, also known as a bionic man, is a robot designed to imitate the appearance and behavior of a human being, especially a kind of robot with a similar body to a human being. The humanoid robot can assist or even replace humans to complete dangerous, heavy and complex work, improve work efficiency and quality, and is widely used in medical, military, education, production and life industries. Among them, the leg mechanism is an important part of the humanoid robot, which directly determines the stability and flexibility of the humanoid robot. Generally, the leg mechanism of the humanoid robot includes corresponding leg joints such as hip joints, knee joints and ankle joints, and each leg joint cooperates with each other to complete a walking motion similar to human motion.

[0003] However, in the traditional design, the leg mechanism has the problem of large inertia. Especially in the calf and foot region, the use of multiple joint modules increases the leg inertia, affecting the motion control and dynamic response of the robot. There are two common design schemes: 1. The joint module providing power is directly connected to the leg joint. When this scheme is adopted, the leg inertia of the robot is large, especially 2-3 joint modules are usually installed on the calf and foot, and the leg inertia of the robot directly affects the dynamic effect. 2. The joint module providing power is installed above the thigh, and a connecting rod is used to drive the knee joint and ankle at the distal end. Although this scheme can reduce the inertia of the calf part to a certain extent, due to the large space occupied by the connecting rod, the joint movement range is limited, the whole leg structure is bulky, and the appearance is poor. SUMMARY

[0004] Therefore, the present application provides a humanoid robot leg mechanism and a robot, which aims to solve the problems of large inertia and poor appearance of the leg mechanism.

[0005] The technical scheme of the present application is as follows:

[0006] In a first aspect, the present application provides a humanoid robot leg mechanism, which comprises a calf skeleton, a thigh skeleton and a foot, the lower end of the thigh skeleton is rotatably connected to the upper end of the calf skeleton through a knee joint pivot, and the foot is rotatably connected to the lower end of the calf skeleton through a naked joint assembly, and further comprising:

[0007] The first power mechanism is arranged in the thigh skeleton and is used for driving the lower leg skeleton to rotate around the knee joint rotating shaft. The first power mechanism comprises a first driving wheel, a first driven wheel, a first transmission rope and a first motor. The first motor is fixed on the thigh skeleton, and an output shaft of the first motor is fixedly connected with the first driving wheel. The first driven wheel is fixed on the end of the lower leg skeleton away from the foot. The first driving wheel and the first driven wheel are transmissionally connected through the first transmission rope.

[0008] The second power mechanism is arranged in two groups and is arranged on the left and right sides of the thigh skeleton. The second power mechanism is used for driving the foot to move around the ankle joint assembly. The second power mechanism comprises 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 skeleton, and an output shaft of the second motor is fixedly connected with the second driving wheel arranged on the outer side of the thigh skeleton. The second driven wheel is arranged on the outer side of the thigh skeleton and is rotationally connected with the knee joint rotating shaft. The second driving wheel and the second driven wheel are transmissionally connected through the second transmission rope. One end of the connecting rod is rotationally connected with the second driving wheel, and the other end of the connecting rod is rotationally connected with the foot.

[0009] On the basis of the above technical scheme, preferably, the thigh skeleton comprises two thigh supports arranged in parallel at intervals. The two thigh supports are fixedly connected. The upper end of the lower leg skeleton is located between the two thigh supports and is rotationally connected with the lower ends of the two thigh supports through the knee joint rotating shaft. The first driving wheel is located on the upper part between the two thigh supports.

[0010] On the basis of the above technical scheme, preferably, the first power mechanism further comprises a tensioning assembly. The tensioning assembly comprises a pressure sensor, a movable tensioning wheel and a sliding seat.

[0011] The sliding seat is horizontally movably installed on the thigh support. The two ends of the movable tensioning wheel are rotationally connected with the sliding seat.

[0012] The first end of the first transmission rope is fixed on the first driven wheel. The first transmission rope sequentially passes through the first driven wheel, the movable tensioning wheel and the first driving wheel, and then passes through the first driven wheel again. The second end of the first transmission rope is fixed on the first driven wheel, so as to form a closed loop transmission.

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

[0014] On the basis of the above technical scheme, preferably, the first power mechanism further comprises a fixed tensioning wheel. The fixed tensioning wheel is rotationally arranged between the two thigh supports. The fixed tensioning wheel is located between the movable tensioning wheel and the first driving wheel or the second driving wheel. The first transmission rope passes through the fixed tensioning wheel before or after passing through the movable tensioning wheel.

[0015] On the basis of the above technical scheme, preferably, the thigh skeleton further comprises a limiting frame, the limiting frame 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 skeleton; when the calf skeleton swings forward around the knee joint shaft, the limiting frame contacts the calf skeleton to limit the swing angle thereof.

[0016] On the basis of the above technical scheme, preferably, the second driving wheel comprises an inner wheel and an outer wheel, the inner wheel is arranged outside the thigh support and is fixedly connected with the output shaft of the second motor, the outer wheel is rotatably arranged outside the inner wheel, the second transmission rope comprises an inner transmission rope and an outer transmission rope, the inner transmission rope is transmissionally connected between the inner wheel and the second driven wheel, and the two ends of the inner transmission rope are fixedly connected with the inner wheel and the second driven wheel respectively, the outer transmission rope is transmissionally connected between the outer wheel and the second driven wheel, and the two ends of the outer transmission rope are fixedly connected with the outer wheel and the second driven wheel respectively, the inner transmission rope and the outer transmission rope are mirror arranged relative to the center line of the second driving wheel and the second driven wheel in space, a loosening prevention device is arranged between the inner wheel and the outer wheel, the loosening prevention device comprises a ratchet wheel, a pawl and a torsional spring, the ratchet wheel is fixedly arranged outside the inner wheel, the pawl is rotatably arranged inside the outer wheel, and the pawl is connected with the ratchet wheel, the winding direction of the inner transmission rope on the inner wheel is the same as the direction in which the pawl passes over the ratchet wheel, the winding direction of the outer transmission rope on the outer wheel is opposite to the direction in which the pawl passes over the ratchet wheel, and the torsional spring is arranged at the rotation shaft of the inner wheel and the outer wheel, and the tension direction of the torsional spring is the same as the direction in which the pawl passes over the ratchet wheel.

[0017] On the basis of the above technical scheme, preferably, the foot comprises a foot sole and a mounting seat fixedly arranged at the upper portion of the foot sole, the lower end of the calf skeleton is rotatably connected with the mounting seat through a naked joint assembly, the naked joint assembly comprises a pitch rotation shaft and a roll rotation shaft, the axis of the pitch rotation shaft extends along the left-right direction of the foot, allowing the foot to be flipped forward and backward relative to the calf skeleton, the axis of the roll rotation shaft is perpendicular to the pitch rotation shaft and extends along the front-rear direction of the foot, allowing the foot to be flipped left and right relative to the calf skeleton, and the mounting seat is provided with a connecting portion rotatably connected with the connecting rod on both sides of the front side of the calf skeleton.

[0018] On the basis of the above technical scheme, preferably, further comprising a hip joint assembly connected with the upper end of the thigh skeleton, the hip joint assembly comprises 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 at the front side of the base, the third motor is fixedly arranged at 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 at the top surface of the first connecting seat and is used to drive the second connecting seat to horizontally revolve, the thigh skeleton is located at one side of the second connecting seat, and the fifth motor is fixedly arranged at the other side of the second connecting seat and is used to drive the thigh skeleton to swing forward and backward.

[0019] In a second aspect, the present application discloses a robot comprising the humanoid robot leg mechanism of the first aspect.

[0020] The present application has the following beneficial effects over the prior art:

[0021] (1) The humanoid robot leg mechanism disclosed in the present application can effectively reduce the inertia of the entire leg by concentrating all the power mechanisms on the thigh skeleton, so that the robot can exhibit higher flexibility in movement. By adopting an integrated power transmission system, most of the power mechanisms and joint assemblies are placed inside or on both sides of the thigh skeleton, thereby reducing the space occupied by the leg structure in the traditional design, avoiding the bulky appearance of the leg, and improving the aesthetic appearance.

[0022] (2) Since the leg transmission system needs to realize 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 design of the lower leg and foot structure, which can avoid the space occupation caused 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 the dynamic tensioning wheel and the 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 and are fixedly connected with 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 tensioning wheel tensions the first transmission rope to avoid slipping with the first driving wheel due to the relaxation of the first transmission rope. The pressure sensor monitors the tension of the transmission rope in real time. When the first transmission rope relaxes, the position of the sliding seat can be adjusted to restore the tensioning operation of the dynamic tensioning wheel on the first transmission rope, thereby achieving the demand of motion transmission.

[0024] (4) By setting the fixed tensioning wheel, the fixed tensioning wheel serves as a fixed fulcrum to disperse the adjustment pressure of the dynamic tensioning wheel, and divides the transmission path into a dynamic adjustment section (dynamic tensioning wheel) and a fixed support section (fixed tensioning wheel). By arranging double wheels, the contact angle between the transmission rope and the pulley is increased, and the local bending stress concentration is reduced. In addition, after the fixed tensioning wheel is added, the transmission path is smoother, reducing sharp turns and thereby reducing the 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 cooperation and the ratchet pawl anti-loose device, the one-way rotation control of the inner and outer wheels and the stable tensioning of the transmission system are realized. The mirror image setting of the inner transmission rope and the outer transmission rope makes the outer transmission rope be tensioned when the inner wheel rotates clockwise, and the second driven wheel drives the foot movement; when the inner wheel rotates counterclockwise, the second driven wheel is driven to rotate counterclockwise through the inner transmission rope, and the reverse action of the outer transmission rope keeps the outer wheel synchronous rotation. The torsional spring in the anti-loose device can re-tension the outer transmission rope through the pre-tightening force when the outer transmission rope is loose, so as to ensure that the system always maintains appropriate tension, and improve the reliability of power transmission and the flexibility of the robot leg. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0027] Figure 1 A perspective view of the leg mechanism of the humanoid robot disclosed in the present application is shown in the figure.

[0028] Figure 2 A front view of the leg mechanism of the humanoid robot disclosed in the present application is shown in the figure.

[0029] Figure 3 An assembly structure diagram of the tensioning assembly and the thigh skeleton disclosed in the present application is shown in the figure.

[0030] Figure 4 An assembly structure diagram of the first power mechanism, the thigh skeleton and the calf skeleton disclosed in the present application is shown in the figure.

[0031] Figure 5 A perspective view of the second power structure disclosed in the present application is shown in the figure.

[0032] Figure 6 A plan view of the second power structure disclosed in the present application is shown in the figure.

[0033] Figure 7 A perspective view of the second power structure disclosed in the present application is shown in the figure. Figure 5 An enlarged view of part A in the figure.

[0034] Figure 8 An enlarged view of part B in the figure. Figure 5 An enlarged view of part B in the figure.

[0035] Reference signs:

[0036] 1. Lower leg frame; 2. Thigh frame; 3. Foot; 4. Knee joint pivot; 5. Bare-knee 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 support; 65. Tensioning assembly; 651. Pressure sensor; 652. Movable tensioning wheel; 653. Sliding seat; 210 654. Sliding hole; 711. Tensioner wheel; 712. Limiting frame; 731. Inner wheel; 732. Outer wheel; 733. Inner drive rope; 734. Outer drive rope; 75. Anti-loosening device; 751. Ratchet; 752. Pad; 753. Torsion spring; 31. Foot; 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 Implementation

[0037] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0038] like Figure 1 As shown, combined with Figures 2-4 This invention discloses a humanoid robot leg mechanism, including a lower leg skeleton 1, a thigh skeleton 2, and a foot 3. The lower end of the thigh skeleton 2 is rotatably connected to the upper end of the lower leg skeleton 1 via a knee joint pivot 4, and the foot 3 is rotatably connected to the lower end of the lower leg skeleton 1 via a bare joint assembly 5. This structural design ensures leg flexibility and coordinated joint movements, enabling the robot to perform gait and movements similar to those of a human.

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

[0040] The first power mechanism 6 is located inside the thigh frame 2 and is used to drive the lower leg frame 1 to rotate around the knee joint pivot 4. It includes 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 lower leg frame 1 away from the foot 3. The first driving wheel 61 and the first driven wheel 62 are connected by the first transmission rope 63.

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

[0042] Since the first power mechanism 6 is located inside the thigh skeleton 2, compared with the traditional design of installing the power module on the lower leg, the increase of the inertia of the lower leg part is avoided, the motion control and dynamic response performance of the robot are improved, and the appearance 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 is used to drive the foot 3 to move around the naked joint assembly 5. It includes 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 arranged on the thigh skeleton 2, and the output shaft thereof is fixedly connected with the second driving wheel 71 arranged on the outer side of the thigh skeleton 2. The second driven wheel 72 is arranged on the outer side of the thigh skeleton 2 and is rotationally connected with the knee joint shaft 4. The second driving wheel 71 and the second driven wheel 72 are transmissionally connected through the second transmission rope 73. One end of the connecting rod 75 is rotationally connected with the second driving wheel 71, and the other end thereof is rotationally connected with 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, 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, and the second driving wheel 71 drives the foot 3 to move around the naked joint assembly 5 through the rotation of the connecting rod 75, thereby reducing the complexity of the lower leg part and making the movement of the foot 3 more flexible. By distributing the power device on the thigh, the complex structure and high inertia problem of the lower leg and the foot 3 are avoided, and the motion performance of the robot is improved. Moreover, the connecting rod 75 transmission scheme reduces the volume occupied by multiple joint modules, so that the whole leg structure is more simple and compact.

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

[0046] The human-shaped robot leg mechanism discloses in the application can effectively reduce the inertia of the whole leg by concentrating all the power mechanisms on the thigh skeleton 2, the robot can show higher flexibility in movement, the integrated power transmission system is adopted, most of the power mechanisms and joint assemblies are placed inside or on both sides of the thigh skeleton 2, the occupied space of the leg structure in the traditional design is reduced, the appearance of the leg is avoided from being bloated, and the aesthetic appearance is improved.

[0047] As some embodiments, the thigh skeleton 2 in the embodiment comprises two thigh supports 21 arranged in parallel at intervals, and the two thigh supports 21 are fixedly connected, so that the two thigh supports 21 have a certain installation space therebetween, facilitating the installation of parts, in the embodiment, the upper end of the calf skeleton 1 is located between the two thigh supports 21 and is rotationally connected with the lower ends of the two thigh supports 21 through the knee joint rotating shaft 4, and the first driving wheel 61 is located on the upper part between the two thigh supports 21.

[0048] Since the upper end of the calf skeleton 1 is between the two thigh supports 21, the first driven wheel 62 is also located between the two thigh supports 21, so that most of the parts 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 located between the two thigh supports 21, the first power mechanism 6 is integrated in the thigh skeleton 2, on the one hand, the inertia of the calf skeleton 1 in movement is reduced, and on the other hand, the integrated arrangement can fully utilize the internal space of the thigh skeleton 2 and improve the aesthetic appearance of the leg structure.

[0049] In some embodiments, the first transmission rope 63 is a ring-shaped closed steel wire rope or nylon rope, the first transmission rope 63 is sleeved on the outer sides 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 skeleton 1 around the knee joint rotating shaft 4, however, the first transmission rope 63 will be loose in the transmission process, so as to cause the slipping phenomenon of the first transmission rope 63 and the first driving wheel 61 and the first driven wheel 62 in the transmission process.

[0050] In order to solve the above problems, the application adopts the following technical scheme, specifically, referring to FIGS. Figure 3 and 4 As shown in the figures, the first power mechanism 6 in the embodiment further comprises a tensioning assembly 65, the tensioning assembly 65 comprises a pressure sensor 651, a tensioning wheel 652 and a sliding seat 653.

[0051] The sliding seat 653 is horizontally movably installed on the thigh support 21, and the two ends of the dynamic tensioning wheel 652 are rotationally connected with the sliding seat 653. In the embodiment, a sliding hole 210 is horizontally formed in the side wall of the thigh support 21, and the sliding seat 653 is slidingly arranged in the sliding hole 210. The sliding seat 653 can translate in the front-rear direction of the thigh support 2 in the sliding hole 210. In some embodiments, the position of 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 tensioning wheel 652 in the front-rear direction of the thigh support 2 is adjusted.

[0052] The first end of the first transmission rope 63 is fixed to the first driven wheel 62, sequentially passes through the first driven wheel 62, the dynamic tensioning wheel 652 and the first driving wheel 61, and then passes through the first driven wheel 62 again, and the second end is fixed to the first driven wheel 62, forming 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] By adopting the above technical scheme, the first transmission rope 63 passes through the first driving wheel 61, and the two ends of the first transmission rope 63 pass through the first driven wheel 62 and are fixedly connected with the first driven wheel 62. In this way, when the first driving wheel 61 drives the first transmission rope 63 to transmit power, the two ends of the first transmission rope 63 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, so as to avoid the first transmission rope 63 from slipping with the first driving wheel 61 due to relaxation. The pressure sensor 651 is used to monitor the tension of the transmission rope in real time. When the first transmission rope 63 is relaxed, the position of the sliding seat 653 can be adjusted, so that the dynamic tensioning wheel 652 restores the tensioning operation on the first transmission rope 63, and the transmission requirement is met.

[0054] As some embodiments, the first power mechanism 6 further comprises a fixed tensioning wheel 654, which is rotationally arranged between the two thigh supports 21, and the fixed tensioning wheel 654 is located between the dynamic tensioning wheel 652 and the first driving wheel 61 or the second driving wheel 71. The first transmission rope 63 passes through the fixed tensioning wheel 654 before or after passing through the dynamic tensioning wheel 652.

[0055] By adopting the above technical scheme, the fixed tensioning wheel 654 serves as a fixed fulcrum, disperses the adjustment pressure of the dynamic tensioning wheel 652, divides the transmission path into a dynamic adjustment section (the dynamic tensioning wheel 652) and a fixed support section (the fixed tensioning wheel 654), increases the contact angle between the transmission rope and the pulley through the double-wheel layout, and reduces the local bending stress concentration. In addition, after the fixed tensioning wheel 654 is added, the transmission path is smoother, the sharp turns are reduced, and the friction and wear between the transmission rope and the pulley are reduced.

[0056] The fixed tensioner 654 fixes the reference tension of the transmission rope, the movable tensioner 652 compensates the tension change through the sliding seat 653, the double-wheel cooperation reduces the risk of transmission rope slackening, and the closed-loop transmission rigidity is maintained.

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

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

[0059] As some embodiments, the thigh frame 2 further comprises a limiting frame 22, which is fixedly arranged at the lower end of the two thigh supports 21 and located in front of the swing path of the calf frame 1; when the calf frame 1 swings forward around the knee joint shaft 4, the limiting frame 22 contacts the calf frame 1 to limit the swing angle thereof.

[0060] By adopting the above technical scheme, the limiting frame 22 directly intervenes in the forward swing path of the calf frame 1 as a rigid blocking structure, simulates the physiological limitation of the human knee joint (the human calf cannot be forward flexed), and replaces pure software or sensor control through physical contact to ensure the absolute safety of mechanical movement.

[0061] In the embodiment, in order to realize the movement of the foot 3, the second transmission rope 73 is in a closed loop shape and is sleeved outside the second driving wheel 71 and the second driven wheel 72; the second driving wheel 71 is driven to rotate by the second motor 74, and then the second driven wheel 72 is driven to rotate by the second transmission rope 73, so as to realize the rotation of the foot 3. However, the second transmission rope 73 will be loose in the transmission process, so as to cause the slippage phenomenon of the second transmission rope 73 and the second driving wheel 71 and the second driven wheel 72 in the transmission process.

[0062] In order to solve the above problems, the application adopts the following technical scheme. Figures 5-7 As shown in the accompanying drawings, the second power mechanism 7 is structurally improved in the embodiment, the second driving wheel 71 comprises an inner wheel 711 and an outer wheel 712, the inner wheel 711 is arranged outside the thigh support 21 and is fixedly connected with 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 driving transmission system.

[0063] The outer wheel 712 is coaxially arranged outside the inner wheel 711, and the second transmission rope 73 comprises an inner transmission rope 731 and an outer transmission rope 732. The inner transmission rope 731 is in transmission connection between the inner wheel 711 and the second driven wheel 72, and the two ends of the inner transmission rope 731 are fixedly connected with the inner wheel 711 and the second driven wheel 72 respectively. The outer transmission rope 732 is in transmission connection between the outer wheel 712 and the second driven wheel 72, and the two ends of the outer transmission rope 732 are fixedly connected with the outer wheel 712 and the second driven wheel 72 respectively. The inner transmission rope 731 and the outer transmission rope 732 are mirror images relative to the center line of the second driving wheel 71 and the second driven wheel 72 in space. The anti-loosening device 75 is arranged between the inner wheel 711 and the outer wheel 712. The anti-loosening device 75 comprises a ratchet wheel 751, a pawl 752 and a torsion spring 753. The ratchet wheel 751 is fixedly arranged outside the inner wheel 711. The pawl 752 is rotatably arranged inside the outer wheel 712 and is in cooperation with the ratchet wheel 751. The winding direction of the inner transmission rope 731 on the inner wheel 711 is the same as the direction of the pawl 752 passing through the ratchet wheel 751. The winding direction of the outer transmission rope 732 on the outer wheel 712 is opposite to the direction of the pawl 752 passing through the ratchet wheel 751. The torsion spring 753 is arranged at the rotation shaft of the inner wheel 711 and the outer wheel 712. The tension direction of the torsion spring 753 is the same as the direction of the pawl 752 passing through the ratchet wheel 751.

[0064] In the embodiment, the outer wheel 712 is coaxially arranged outside the inner wheel 711 and is in transmission control with the inner wheel 711 through the cooperation of the ratchet wheel 751 and the pawl 752. The rotation of the outer wheel 712 is closely related to the rotation direction of the inner wheel 711. The rotation direction of the inner wheel 711 affects the movement of the outer wheel 712 through the linkage of the ratchet wheel 751 and the pawl 752.

[0065] In the embodiment, the ratchet wheel 751 is fixed outside the inner wheel 711, and the pawl 752 is rotatably arranged inside the outer wheel 712 and cooperates with the ratchet wheel 751. The ratchet wheel 751 ensures that the rotation between the inner wheel 711 and the outer wheel 712 is unidirectional through the cooperation with the pawl 752, and prevents reverse rotation. As some embodiments, the cooperation of the tooth surface of the ratchet wheel 751 and the pawl 752 makes the outer wheel 712 also rotate clockwise when the inner wheel 711 rotates clockwise, and cannot reverse. 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 rotates when the inner wheel 711 rotates clockwise, and the outer wheel 712 can remain stationary when the inner wheel 711 rotates counterclockwise.

[0066] The torsion spring 753 is located at the rotation shaft of the inner wheel 711 and the outer wheel 712, and ensures that the two wheels rotate in the direction of tensioning the transmission rope through the tension of the torsion spring 753. The function of the torsion spring 753 is to maintain the proper tension of the transmission rope when the transmission rope is loose, and to prevent the transmission rope from loosening.

[0067] By mirroring the inner transmission rope 731 and the outer transmission rope 732 relative to the center line of the second driving wheel 71 and the second driven wheel 72 in space, 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 of the pawl 752 over the ratchet wheel 751, and the winding direction of the outer transmission rope 732 on the outer wheel 712 is opposite to the direction of the pawl 752 over the ratchet wheel 751. Therefore, the inner transmission rope 731 and the outer transmission rope 732 can be tightened in different directions of rotation of the inner wheel.

[0068] Specifically, when the inner wheel 711 rotates clockwise, the engagement of the ratchet wheel 751 and the pawl 752 causes 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 of the pawl 752 over the ratchet wheel 751, the tension of the inner transmission rope 731 on the inner wheel 711 decreases and relaxes at this time. The outer wheel 712 rotates clockwise with the inner wheel 711, and since the winding direction of the outer transmission rope 732 on the outer wheel 712 is opposite to the direction of the pawl 752 over the ratchet wheel 751, the outer transmission rope 732 is tightened between the outer wheel 712 and the second driven wheel 72. The second driven wheel 72 rotates clockwise under the driving of the outer transmission rope 732. As the second driven wheel 72 rotates clockwise, it winds 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 synchronously clockwise at this time, the torsional spring 753 does not generate tension between them.

[0069] When the inner wheel 711 rotates counterclockwise, the ratchet wheel 751 will pass over 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 of the pawl 752 over the ratchet wheel 751, the inner transmission rope 731 is tightened at this time. The inner transmission rope 731 drives the second driven wheel 72 to rotate counterclockwise. When the second driven wheel 72 rotates counterclockwise, it exerts a counterclockwise rotating force on the outer wheel 712 through the outer transmission rope 732. At this time, if the outer transmission rope 732 is tightened 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 loosens during long-term use (due to peristalsis causing the length to increase), since the torsional spring 753 has an initial pre-tightening force, its tension will drive the outer wheel 712 to rotate clockwise relative to the inner wheel 711. This clockwise rotating tendency acts on the outer transmission rope 732, causing it to be tightened again.

[0070] By improving the structure of the second power mechanism, adopting the design of inner and outer wheel cooperation and the ratchet pawl anti-loose device, one-way rotation control of the inner and outer wheels and stable tensioning of the transmission system are realized. The mirror image setting of the inner transmission rope and the outer transmission rope makes the outer transmission rope be tensioned when the inner wheel rotates clockwise, and the second driven wheel drives the foot movement; when the inner wheel rotates counterclockwise, the second driven wheel is driven to rotate counterclockwise through the inner transmission rope, and the reverse action of the outer transmission rope keeps the outer wheel synchronous rotation. The torsional spring in the anti-loose device can re-tension 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 leg.

[0071] As some embodiments, refer to the accompanying Figure 8 As shown in the figure, the foot 3 includes a foot sole 31 and a mounting seat 32 fixedly arranged on the upper part of the foot sole 31, the lower end of the shank skeleton 1 is rotationally connected with the mounting seat 32 through a naked joint assembly 5, the naked joint assembly 5 includes a pitch rotation shaft 51 and a roll rotation shaft 52, the axis of the pitch rotation shaft 51 extends along the left-right direction of the foot 3, allowing the foot 3 to flip forward and backward relative to the shank skeleton 1, the axis of the roll rotation shaft 52 is perpendicular to the pitch rotation shaft 51 and extends along the front-back direction of the foot 3, allowing the foot 3 to flip left and right relative to the shank skeleton 1, and the mounting seat 32 on the front side of the shank skeleton 1 is provided with a connecting part 321 rotationally connected with a connecting rod 75 on both sides.

[0072] By adopting the above technical scheme, through the setting of the pitch rotation shaft 51 and the roll rotation shaft 52, the entire foot 3 will make pitch and roll movements relative to the lower end of the shank skeleton 1. Specifically, when the rotation directions and speeds of the second driven wheels 72 in the two second power mechanisms 7 are consistent, the two second driven wheels 72 form a connecting rod 75 mechanism through the connecting rod 75 and the connecting part 321 on the mounting seat 32, at this time, the entire foot 3 flips forward and backward relative to the shank skeleton 1 through the pitch rotation shaft 51 under the action of the connecting rod 75 mechanism. When the rotation directions of the second driven wheels 72 in the two second power mechanisms 7 are inconsistent, the lower ends of the two connecting rods 75 are not at the same height, at this time, the entire foot 3 flips left and right relative to the shank skeleton 1 through the roll rotation shaft 52 under the action of the connecting rod 75 mechanism.

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

[0074] The rotation of the first connecting seat 82 in the vertical direction driven by the third motor 84 can control the angle change between the thigh skeleton 2 and the torso, so as to make the whole leg swing left and right. The horizontal rotation of the second connecting seat 83 controlled by the fourth motor 85 makes the robot more accurately adjust the angle of the thigh skeleton 2. In this way, the robot can adjust the leg angle when turning and turning the body to ensure balance when moving. The forward and backward swinging of the thigh skeleton 2 controlled by the fifth motor 86 is one of the core mechanisms to simulate gait. By adjusting the forward and backward swinging, the robot can advance or retreat like a human being, showing a natural walking action. This control mode makes the gait of the robot more flexible and natural, enabling it to walk efficiently in complex environments.

[0075] The setting of the hip joint assembly 8 can make the whole leg have three degrees of freedom, i.e., left and right swinging, forward and backward swinging, and horizontal swinging.

[0076] The robot provided by the application can effectively reduce the inertia of the whole leg and show higher flexibility in movement, and at the same time, most of the power mechanism and joint assembly are placed inside or on both sides of the thigh skeleton 2, reducing the occupied space of the leg structure in the traditional design, avoiding the appearance of bloated legs, and improving the appearance of the robot.

[0077] The above only describes the preferred embodiments of the application and is not intended to limit the application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the application shall be included in the protection scope of the application.

Claims

1. A humanoid robot leg mechanism characterized by comprising: The lower end of the thigh skeleton is rotatably connected with the upper end of the calf skeleton through a knee joint pivot, the foot is rotatably connected with the lower end of the calf skeleton through a naked joint assembly, and the device further comprises: A first power mechanism is arranged inside the thigh skeleton and used for driving the calf skeleton to rotate around the knee joint pivot, and the first power mechanism comprises a first driving wheel, a first driven wheel, a first transmission rope and a first motor, the first motor is fixed on the thigh skeleton, the output shaft of the first motor is fixedly connected with the first driving wheel, the first driven wheel is fixed on the end of the calf skeleton away from the foot, and the first driving wheel and the first driven wheel are transmissionally connected through the first transmission rope; A second power mechanism is arranged in two groups and located on the left and right sides of the thigh skeleton, used for driving the foot to move around the naked joint assembly, and the second power mechanism comprises 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 skeleton, the output shaft of the second motor is fixedly connected with the second driving wheel arranged on the outside of the thigh skeleton, the second driven wheel is arranged on the outside of the thigh skeleton and rotatably connected with the knee joint pivot, the second driving wheel and the second driven wheel are transmissionally connected through the second transmission rope, one end of the connecting rod is rotatably connected with the second driving wheel, and the other end is rotatably connected with the foot; The thigh skeleton comprises two thigh supports arranged in parallel at intervals, the two thigh supports are fixedly connected, the upper end of the calf skeleton is located between the two thigh supports and rotatably connected with the lower ends of the two thigh supports through the knee joint pivot, and the first driving wheel is located on the upper part between the two thigh supports; The second driving wheel comprises an inner wheel and an outer wheel, the inner wheel is arranged on the outside of the thigh support and fixedly connected with the output shaft of the second motor, the outer wheel is rotatably arranged on the outside of the inner wheel, the second transmission rope comprises an inner transmission rope and an outer transmission rope, the inner transmission rope is transmissionally connected between the inner wheel and the second driven wheel, and the two ends of the inner transmission rope are fixedly connected with the inner wheel and the second driven wheel respectively, the outer transmission rope is transmissionally connected between the outer wheel and the second driven wheel, and the two ends of the outer transmission rope are fixedly connected with the outer wheel and the second driven wheel respectively, the inner transmission rope and the outer transmission rope are mirror arranged relative to the center line of the second driving wheel and the second driven wheel in space, a loosening prevention device is arranged between the inner wheel and the outer wheel, the loosening prevention device comprises a ratchet wheel, a pawl and a torsional spring, the ratchet wheel is fixedly arranged on the outside of the inner wheel, the pawl is rotatably arranged on the inside of the outer wheel and connected with the ratchet wheel in a matched mode, the winding direction of the inner transmission rope on the inner wheel is the same as the direction of the pawl passing over the ratchet wheel, the winding direction of the outer transmission rope on the outer wheel is opposite to the direction of the pawl passing over the ratchet wheel, and the torsional spring is arranged at the rotating shaft of the inner wheel and the outer wheel, and the tension direction of the torsional spring is the same as the direction of the pawl passing over the ratchet wheel.

2. The humanoid robot leg mechanism according to claim 1, characterized by: The first power mechanism further comprises a tensioning assembly, the tensioning assembly comprises a pressure sensor, a movable tensioning wheel and a sliding seat; The sliding seat is horizontally movably arranged on the thigh support, and the two ends of the movable tensioning wheel are rotatably connected with the sliding seat; The first end of the first transmission rope is fixed on the first driven wheel, sequentially passes through the first driven wheel, the movable tensioning wheel and the first driving wheel, again passes through the first driven wheel, and the second end is fixed on the first driven wheel, so as 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.

3. The humanoid robot leg mechanism according to claim 2, characterized by: The first power mechanism further comprises a fixed tensioner, which is rotatably arranged between the two thigh supports and located between the movable tensioner and the first or second driving wheel, and the first transmission rope passes around the fixed tensioner before or after passing around the movable tensioner.

4. The humanoid robot leg mechanism according to claim 1, characterized by: The thigh support further comprises a limiting frame, which is fixedly arranged at the lower end of the two thigh supports and located in front of the swing path of the lower leg support, and the limiting frame contacts the lower leg support to limit the swing angle of the lower leg support when the lower leg support swings forward around the knee joint pivot.

5. The humanoid robot leg mechanism according to claim 1, characterized by: The foot comprises a foot sole and a mounting seat fixedly arranged at the upper part of the foot sole, the lower end of the lower leg support is rotatably connected with the mounting seat through a naked joint assembly, the naked joint assembly comprises a pitch pivot and a roll pivot, the axis of the pitch pivot extends along the left-right direction of the foot and allows the foot to be flipped forward and backward relative to the lower leg support, the axis of the roll pivot is perpendicular to the pitch pivot and extends along the front-back direction of the foot and allows the foot to be flipped left and right relative to the lower leg support, and the mounting seat is provided with a connecting part rotatably connected with the connecting rod on both sides of the front side of the lower leg support.

6. The humanoid robot leg mechanism according to claim 1, characterized by: The hip joint assembly is further connected with the upper end of the thigh support, the hip joint assembly comprises 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 at the front side of the base, the third motor is fixedly arranged at the rear side of the base and 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 at the top surface of the first connecting seat and used to drive the second connecting seat to horizontally revolve, the thigh support is located at one side of the second connecting seat, and the fifth motor is fixedly arranged at the other side of the second connecting seat and used to drive the thigh support to swing forward and backward.

7. A robot, characterized in that The humanoid robot leg mechanism comprises the humanoid robot leg mechanism according to any one of claims 1 to 6.

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