Crus structure of humanoid robot

Abstract

The shank structure of the humanoid robot comprises a knee joint module, an ankle joint module and a rack, all the modules are sequentially connected according to the position sequence of human joints and have three degrees of freedom, each joint is driven by a direct-current motor, and mechanical limiting is arranged to guarantee safety. The rack is presented in the form of a thigh shell of a humanoid robot; the knee joint module comprises a first knee joint connecting rod, a second knee joint connecting rod, a gear set and a direct current motor; the ankle joint module comprises a shank connecting rod, an ankle joint left transmission connecting rod, an ankle joint right transmission connecting rod, a first left motor connecting rod, a second left motor connecting rod, a first right motor connecting rod, a second right motor connecting rod, an ankle joint universal joint, a gear set and two direct current motors.

Description

Technical Field

[0001] This invention belongs to the field of robotics technology, specifically relating to a leg structure for a humanoid robot. Background Technology

[0002] Humanoid robots, also known as humanoid robots, are robots whose shape and size are similar to the human body, capable of mimicking human movement, expressions, interactions, and actions. Simply put, they are robots with a human form, including a head, torso, arms, and legs, capable of performing the movements and tasks that humans can perform, and possessing similar perceptual, learning, and cognitive abilities. Based on their design type, humanoid robots can be categorized into legged, mobile, multi-functional, and performance robots.

[0003] In the field of robotics, humanoid robots have always been a popular research area, and creating near-human automated machinery has always been the ultimate goal of researchers. With the continuous maturation of technology, people have begun to explore the enormous potential of humanoid robots as general-purpose automated equipment to replace factory workers, investing significant resources in their research and development. Because humanoid robots can seamlessly integrate into workflows and collaborate with human workers, unlike other automated equipment that requires specially designed environments and tools, this gives them greater application value.

[0004] Currently, the drive modules of humanoid robots, such as motors and hydraulic components, still struggle to achieve the torque-to-weight ratio of human muscles. Furthermore, the lightweight and strength of humanoid robot structural components cannot compare to those of human leg bones, thus limiting the movement frequency of the robot's legs and preventing them from swinging at higher frequencies. On the other hand, existing humanoid robot leg structures also suffer from structural complexity, numerous parts, and complicated assembly and maintenance.

[0005] Most existing robots achieve humanoid motion by placing drive modules in situ at the joints of the leg structure, enabling rotation of the thigh, lower leg, and foot. However, existing robot leg structures typically suffer from high rotational inertia during humanoid motion, limiting the frequency of movement. Summary of the Invention

[0006] The purpose of this invention is to provide a structure for the knee to ankle joints of a humanoid robot. The knee joint has one degree of freedom, and the ankle joint has two degrees of freedom, each driven by a DC motor. Mechanical limits are provided at the joints to ensure safety.

[0007] To solve the above-mentioned technical problems, the technical solution of the present invention is: a lower leg structure for a humanoid robot, comprising a knee joint module, an ankle joint module, and a frame. The modules are connected sequentially according to the positional order of human joints, possessing three degrees of freedom. Each joint is driven by a DC motor, and mechanical limits are provided to ensure safety. The frame is presented in the form of a humanoid robot's thigh shell. The knee joint module includes a first knee joint link, a second knee joint link, a gear set, and a DC motor. The ankle joint module includes a lower leg link, a left ankle joint transmission link, a right ankle joint transmission link, a first left motor link, a second left motor link, a first right motor link, a second right motor link, an ankle joint universal joint, a gear set, and two DC motors.

[0008] Preferably, the knee joint module has one degree of freedom for knee flexion / extension, and the knee joint actuator is placed in the middle of the thigh. The motion is transmitted to the knee joint position through a linkage structure, which reduces the weight concentration at the distal end and simplifies the structure.

[0009] Preferably, the ankle joint module has two degrees of freedom: ankle flexion / extension and inversion / eversion. The ankle joint actuator is placed at the knee joint, and the motion is transmitted to the ankle joint position through a linkage structure, which reduces the weight of the distal mass concentration and simplifies the structure.

[0010] Preferably, the ankle universal joint includes an ankle universal joint connector, a front ankle universal joint bearing, a rear ankle universal joint bearing, an ankle universal joint pivot, a left ankle universal joint bearing, and a right ankle universal joint bearing.

[0011] Preferably, the ankle joint module has a humanoid robot foot at its end.

[0012] Preferably, the frame housing provides certain support and protection.

[0013] The beneficial effects of this invention are:

[0014] 1. The lower leg structure of the humanoid robot provided by the present invention can realize three movements: knee flexion / extension, ankle flexion / extension, and ankle inversion / eversion, and the movement of each joint is driven by a DC motor.

[0015] 2. The lower leg structure of the humanoid robot provided by the present invention places the knee joint actuator in the middle of the thigh and the ankle joint actuator at the knee joint. The motion is transmitted to the corresponding position through the linkage structure. While reducing the mass at the distal end and concentrating the weight, the overall structure is simplified and space is saved. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the lower leg structure of a humanoid robot according to the present invention;

[0017] Figure 2 This is a schematic diagram of the knee joint module structure of the present invention;

[0018] Figure 3 This is a schematic diagram of the ankle joint universal joint structure of the present invention.

[0019] Explanation of reference numerals in the attached drawings: 1. Robot thigh shell; 2. Robot foot; 3. Knee joint motor; 4. Knee joint gear set; 5. First knee joint link; 6. Second knee joint link; 7. Left ankle joint motor; 8. Right ankle joint motor; 9. Knee joint pivot; 10. First left motor link; 11. Second left motor link; 12. First right motor link; 13. Second right motor link; 14. Left ankle joint drive link; 15. Right ankle joint drive link; 16. Lower leg link; 17. Ankle joint universal joint; 18. Link connector; 19. Bearing; 20. Ankle joint universal joint connector; 21. Ankle joint universal joint front bearing; 22. Ankle joint universal joint rear bearing; 23. Ankle joint universal joint pivot; 24. Ankle joint universal joint left bearing; 25. Ankle joint universal joint right bearing. Detailed Implementation

[0020] To make the technical problems, technical solutions and advantages of the present invention clearer, the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0021] In the description of this invention, the terms "upper," "lower," "front," "rear," "left," and "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and do not require the invention to be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the invention. The terms "connected," "linked," and "set up" used in this invention should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; a direct connection or an indirect connection through intermediate components; a wired connection, a radio connection, or a wireless communication signal connection. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0022] like Figures 1 to 2As shown, the present invention provides a lower leg structure for a humanoid robot, including a knee joint module, an ankle joint module, and a frame. The modules are connected sequentially according to the positional order of human joints, possessing three degrees of freedom. Each joint is driven by a DC motor, and mechanical limits are provided for safety. The frame is presented in the form of a humanoid robot thigh shell 1. The knee joint module includes a first knee joint link 5, a second knee joint link 6, a gear set, and a DC motor. The ankle joint module includes a first left motor link 10, a second left motor link 11, a first right motor link 12, a second right motor link 13, a left ankle joint transmission link 14, a right ankle joint transmission link 15, a lower leg link 16, an ankle joint universal joint 17, a gear set, and two DC motors. The knee joint module has one degree of freedom for knee flexion / extension. The knee joint actuator is placed in the middle of the thigh, and the motion is transmitted to the knee joint position through the link structure, reducing the concentrated weight at the distal end and simplifying the structure. The ankle joint module has two degrees of freedom: ankle flexion / extension and inversion / eversion. The ankle joint actuator is placed at the knee joint, and motion is transmitted to the ankle joint position via a linkage structure, reducing the concentrated weight at the distal end and simplifying the structure. The ankle joint universal joint includes an ankle joint connector 20, a front ankle joint bearing 21, a rear ankle joint bearing 22, an ankle joint universal joint pivot 23, a left ankle joint bearing 24, and a right ankle joint bearing 25. The ankle joint module has a humanoid robot foot at its end. The frame shell provides support and protection.

[0023] To enable humanoid robots to achieve human-like movement, the natural range of motion of a normal human body needs to be considered. The human leg has multiple degrees of freedom, typically six degrees of freedom are sufficient to accurately capture the main kinematic properties. Of these six degrees of freedom, three are located at the hip joint, one at the knee joint, and two at the ankle joint. The lower leg-related parts are the knee and ankle joint movements. Knee joint movements are referred to as flexion / extension, while ankle joint movements mainly include ankle flexion / extension and inversion / eversion. Furthermore, differences between humanoid robots arise from the placement of actuators and whether they use parallel or coaxial mechanisms.

[0024] In this embodiment, to achieve humanoid motion, the range of motion of the humanoid robot should be approximately the same as the range of motion of human joints. The ranges of motion for each degree of freedom are: knee flexion / extension 0~145°, ankle flexion / extension -20~45°, and ankle inversion / eversion -30~30°. Based on the range of motion for each degree of freedom, mechanical limiting structures are set on each joint to ensure safety.

[0025] In this embodiment, the actuator knee joint motor 3 of the knee joint module is placed in the middle of the thigh. The knee joint motor 3 is transmitted to the first knee joint link 5 after being transformed by the knee joint gear set 4. The first knee joint link 5 is eccentrically mounted on the end gear to achieve rotation. The other end of the first knee joint link 5 is connected to the second knee joint link 6 through the link connector 18. The second knee joint link 6 can rotate around the knee joint pivot 9.

[0026] In this embodiment, the ankle joint module's left ankle joint motor 7 and right ankle joint motor 8 are placed at the knee joint. When the left ankle joint motor 7 rotates, it drives the first left motor connecting rod 10 to rotate. The first left motor connecting rod 10 is connected to the second left motor connecting rod 11, and the second left motor connecting rod 11 is connected to the left ankle joint transmission connecting rod 14. When the right ankle joint motor 8 rotates, it drives the first right motor connecting rod 12 to rotate. The first right motor connecting rod 12 is connected to the second right motor connecting rod 13, and the second right motor connecting rod 13 is connected to the right ankle joint transmission connecting rod 15. Both the left ankle joint transmission connecting rod 14 and the right ankle joint transmission connecting rod 15 are connected to the robot foot 2 via small universal joints. The upper end of the lower leg connecting rod 16 can rotate around the knee joint pivot 9, and the lower end is fixed to the ankle joint universal joint 17. The ankle joint universal joint 17 is mounted on the robot foot 2.

[0027] A schematic diagram of the ankle joint universal joint 17 of the present invention is shown below. Figure 3 As shown, it mainly consists of six parts. In this embodiment, the left and right ankle universal joint bearings 24 and 25 can be spliced ​​together in the axial direction and fixed to the foot 2 with screws. The ankle universal joint shaft 23 can rotate in one direction through the left and right ankle universal joint bearings 24 and 25. The front and rear ankle universal joint bearings 21 and 22 are spliced ​​together through the ankle universal joint connector 20. The upper end of the ankle universal joint connector 20 is connected to the lower leg connecting rod 16. The ankle universal joint shaft 23 can rotate in another direction through the front and rear ankle universal joint bearings 21 and 22.

[0028] Those skilled in the art will recognize that the embodiments described herein are intended to help the reader understand the principles of the invention, and should be understood that the scope of protection of the invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical teachings disclosed in this invention without departing from the spirit of the invention, and these modifications and combinations are still within the scope of protection of this invention.

Claims

1. A leg structure for a humanoid robot, characterized in that: The system includes a knee joint module, an ankle joint module, and a frame. The modules are connected sequentially according to the positional order of the human joints and have three degrees of freedom. Each joint is driven by a DC motor and is equipped with mechanical limiters to ensure safety. The frame is presented in the form of a humanoid robot thigh shell (1). The knee joint module includes a first knee joint link (5), a second knee joint link (6), a gear set, and a DC motor. The ankle joint module includes a first left motor link (10), a second left motor link (11), a first right motor link (12), a second right motor link (13), a left ankle joint transmission link (14), a right ankle joint transmission link (15), a lower leg link (16), an ankle joint universal joint (17), a gear set, and two DC motors.

2. The lower leg structure of a humanoid robot according to claim 1, characterized in that: The knee joint module has one degree of freedom for knee flexion / extension. The knee joint actuator is placed in the middle of the thigh, and the motion is transmitted to the knee joint position through a linkage structure, which simplifies the structure while reducing the weight of the distal mass concentration.

3. The lower leg structure of a humanoid robot according to claim 1, characterized in that: The ankle joint module has two degrees of freedom: ankle flexion / extension and inversion / eversion. The ankle joint actuator is placed at the knee joint, and the motion is transmitted to the ankle joint position through a linkage structure, which reduces the weight of the distal mass concentration and simplifies the structure.

4. The lower leg structure of a humanoid robot according to claim 1, characterized in that: The ankle joint universal joint includes an ankle joint universal joint connector (20), an ankle joint front bearing (21), an ankle joint rear bearing (22), an ankle joint universal joint pivot (23), an ankle joint left bearing (24), and an ankle joint right bearing (25).

5. The lower leg structure of a humanoid robot according to claim 1, characterized in that: The ankle joint module has a humanoid robot foot at its end.

6. The lower leg structure of a humanoid robot according to claim 1, characterized in that: The outer shell of the frame provides certain support and protection.

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