A humanoid robot leg structure based on planetary roller screw

Abstract

The application discloses a humanoid robot leg structure based on a planetary roller screw, and aims to provide a mechanical structure scheme for converting rotary motion into linear motion, and can improve the adaptability and motion stability of a robot in complex terrain. The structure adopts a planetary roller screw as a main transmission element, drives a screw nut through a motor, realizes high-precision push-pull motion, and drives the joint motion of the robot leg. Compared with a traditional gear, hydraulic or linear motor driving mode, the application has higher transmission efficiency, low reverse clearance, low energy consumption and excellent torque transmission characteristics. The structure can realize human-like linear joint motion of the leg, so that the robot can more stably complete complex actions such as walking, standing and jumping, and meanwhile, the maintenance cost is reduced and the system reliability is improved. The application can be widely applied in the fields of humanoid robots, rescue robots and special operation robots.

Description

Technical Field

[0001] This invention relates to the robot leg structure of bipedal humanoid robots, specifically to a humanoid robot leg structure. Background Technology

[0002] Humanoid robots, as an important component of humanoid intelligent systems, have broad application prospects in service, medical, industrial, and rescue fields. The structural design of the robot's legs directly determines its mobility, stability, and energy efficiency. Traditional humanoid robot leg drive methods mainly include motor + gear transmission, hydraulic drive, and linear motor drive, each with its own advantages and disadvantages.

[0003] The electric motor + gear transmission method has a mature structure and high control precision, but it suffers from large mechanical transmission backlash, low transmission efficiency, and high noise. Hydraulic drive offers greater output force and faster dynamic response, but its system is complex, carries the risk of oil leakage, and has high maintenance costs. Linear motor drive, while characterized by high response and high precision, is expensive and its energy efficiency is less than ideal under heavy loads.

[0004] In recent years, planetary roller screws, as a highly efficient linear transmission device, have been widely used in high-precision fields such as aerospace, weaponry, and nuclear power due to their advantages of high load capacity, impact resistance, small size, and high speed. They are also gaining increasing attention in the field of robot joint drives. Planetary roller screws generate line contact rolling friction through meshing rollers, significantly increasing the contact and force-bearing surfaces during the screw transmission process. Compared to ball screws used in precision transmission, they offer high speed, high load capacity, high rigidity, a wide lead range, smaller size, lower noise, and easier maintenance and disassembly, without significant loss in transmission efficiency. Furthermore, planetary roller screw mechanisms have lower backlash than gear drives, which helps improve the control precision of robot joints.

[0005] The design of a robot leg structure based on a planetary roller screw, combined with motor drive, can achieve high-precision position control and efficient power transmission, while optimizing the system's energy efficiency ratio and reducing maintenance costs. Therefore, exploring the application of planetary roller screws in robot leg drive has significant research value and application prospects. Based on this, this invention proposes a humanoid robot leg structure based on a planetary roller screw, referring to… Figure 1 , 2When the bipedal robot walks, the hip joint power supply device rotates, driving the thigh link 2 to rotate. Inside the sleeve 3, the power transmission device rotates, driving the lead screw roller nuts 13 and 18 to rotate, which in turn causes the lead screw 12 to perform a push-pull motion. During the push-pull motion of the lead screw, the bearings fixed to the sleeve bearing connecting frame 7 and the push rod bearing frame 8 will rotate relative to the support. The push-pull motion of the lead screw 12 drives the lower leg link 11 to rotate. The same applies to the lead screw structure of the lower leg. When the two lead screw structures move at the same speed, they drive the foot to pitch, and at the same time, the bearing fixed to the ankle joint longitudinal bearing frame 9 rotates relative to the support. When the two lead screw structures move at opposite speeds, they drive the foot to roll, and the bearing fixed to the ankle joint transverse bearing frame 10 rotates relative to the support. The radiation-resistant outer shell 19 allows the humanoid robot to perform inspections in nuclear power plants with strong radiation without damaging internal components. By changing the working mode of the motor, the transmission direction of the lead screw can be changed, enabling the humanoid legs to achieve different movement purposes to adapt to complex terrain and task requirements. Summary of the Invention

[0006] This invention proposes a humanoid robot leg structure based on a planetary roller screw, which is a robot leg structure that can work stably and continuously in complex terrain and achieve multiple posture goals.

[0007] A humanoid robot leg structure based on a planetary roller screw includes a hip joint motor frame 1, a thigh link 2, a screw sleeve 3, a joint bearing 4, a sleeve fixing component 5, a fisheye bearing 6, a sleeve bearing connecting frame 7, a push rod bearing frame 8, a longitudinal bearing frame for the ankle joint 9, a transverse bearing frame for the ankle joint 10, a lower leg link 11, a planetary roller screw 12, screw roller nuts 13 and 18, a nut fixing sleeve 17, a motor housing 14, a thrust roller bearing 16, a motor base 15, and a radiation-resistant material housing 19.

[0008] The thigh link 2 is connected to the output shaft of the power supply device via a bearing; the power transmission device and the motor frame 1 are fixed to each other; the lead screw sleeve 3 is connected to the thigh link 2 via the sleeve bearing connecting frame 7 and the bearing; the thigh link 2 is connected to the lower leg link 11 via the joint bearing 4; the lead screw structure of the lower leg part is the same as that of the lead screw sleeve 3, and is fixed to the lower leg link 11 via the sleeve fixing part 5 and the fish eye bearing 6; the bottom of the planetary roller lead screw 12 is connected to the foot plate via the fish eye bearing 6; the lower end of the lower leg link 11 is fixed to the ankle joint longitudinal bearing frame 9 and the bearing; the ankle joint longitudinal bearing frame 9 is fixed to the ankle joint transverse bearing frame 10, and the lower end of the ankle joint transverse bearing frame 10 is connected to the foot plate;

[0009] The rollers of the planetary roller screw 12 roll in the threaded grooves inside the screw roller nuts 13 and 18, and the push-pull motion of the screw is realized through the meshing of the threads. The planetary roller screw 12 is located inside the screw sleeve 3 and cooperates with the screw roller nuts 13 and 18. It is fixedly connected to the motor housing 14 through the nut fixing sleeve 17. A thrust roller bearing 16 is embedded between the motor base 15 and the motor housing 14. The motor base 15 and the screw roller nut 18 are coaxially fixed, completing the assembly of the main body of the humanoid robot leg structure based on the planetary roller screw. The outer side of the main body of the humanoid robot leg structure based on the planetary roller screw is covered by a radiation-resistant material shell 19.

[0010] Furthermore, the power output device consists of a motor, a gearbox, and an encoder, which are connected in sequence to output power. By changing the working mode of the motor, the transmission direction of the planetary roller screw 12 can be changed, enabling the humanoid leg to achieve different movement purposes to adapt to complex terrain and task requirements.

[0011] Furthermore, when the humanoid robot walks, the hip joint power supply device rotates, driving the thigh link 2 to rotate; inside the sleeve 3, the power transmission device rotates, driving the lead screw roller nuts 13 and 18 to rotate, thereby causing the planetary roller lead screw 12 to perform push-pull motion; during the push-pull motion of the lead screw, the bearings fixed by the sleeve bearing connecting frame 7 and the push rod bearing frame 8 will rotate relative to the support; the push-pull motion of the planetary roller lead screw 12 drives the lower leg link 11 to rotate; in the lower leg lead screw structure, when the two lead screw structures move at the same speed, it drives the foot to pitch, and at the same time, the bearing fixed by the ankle joint longitudinal bearing frame 9 rotates relative to the support; when the two lead screw structures move at opposite speeds... When the foot moves, it rolls laterally, causing the bearing fixed in the ankle joint's transverse bearing bracket 10 to rotate relative to the support. When the power output device is working, it transmits power to the lead screw roller nuts 13 and 18 through the gearbox and encoder. The rotation of the lead screw roller nuts 13 and 18 drives the planetary roller lead screw 12 to push and pull. The pushing and pulling motion of the planetary roller lead screw 12 is transmitted to the lower leg connecting rod 11 through the sleeve bearing connecting bracket 7 and the push rod bearing bracket 8, thereby realizing the movement of the lower leg. When the two lead screw structures move at the same speed, the foot produces a pitching motion; when the two lead screw structures move at opposite speeds, the foot produces a rolling motion. By changing the working mode of the power output device... This allows for changes in the transmission direction of the lead screw, enabling the humanoid robot's legs to achieve different movement objectives to adapt to complex terrain and task requirements. Through the control of the power output device, the planetary roller lead screw 12 can achieve different transmission directions and speed changes, giving the humanoid robot's legs high flexibility and adaptability in complex terrains such as walking, climbing, and traversing obstacles. During walking, the legs adjust the pushing and pulling motion of the lead screw to achieve different gaits and postures to adapt to different ground conditions. In nuclear plant inspection tasks, it is necessary to walk on narrow passages, stairs, and uneven ground; through the control of the power output device, the planetary roller lead screw 12... The lead screw 12 enables the push-pull motion of the lead screw, allowing the legs to flexibly adjust their gait during walking. When the humanoid robot needs to cross pipes or obstacles, the legs adjust the push-pull motion of the lead screw to achieve pitch and roll motion of the foot, thereby crossing the obstacle and ensuring the smooth progress of the inspection task. In the complex environment of a nuclear plant, the humanoid robot needs to have obstacle avoidance capabilities. Through the efficient transmission of the planetary roller lead screw 12, the humanoid robot's legs can quickly adjust their posture when encountering obstacles. When the humanoid robot detects an obstacle in front, the legs use the push-pull motion of the lead screw to cause the foot to roll, thereby changing the walking direction and avoiding the obstacle.

[0012] Furthermore, the radiation-resistant outer shell 19 enables the humanoid robot to conduct inspections in highly irradiated nuclear plants without damaging internal components.

[0013] The beneficial effects of this invention are as follows:

[0014] By changing the motor's operating mode, the transmission direction of the lead screw can be altered, enabling the humanoid legs to achieve different movement objectives to adapt to complex terrains and task requirements. This fully utilizes the control advantages of planetary roller lead screws. Attached Figure Description

[0015] Figure 1 It is a humanoid robot leg structure based on a planetary roller screw.

[0016] Figure 2 This is an external view of the leg structure of a humanoid robot based on a planetary roller screw.

[0017] Figure 3 This is a diagram of the internal structure of the lead screw sleeve. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0019] like Figure 1 As shown, a humanoid robot leg structure based on a planetary roller screw is characterized in that: the structure includes a hip joint motor frame 1, a thigh connecting rod 2, a screw sleeve 3, a joint bearing 4, a sleeve fixing component 5, a fisheye bearing 6, a sleeve bearing connecting frame 7, a push rod bearing frame 8, a longitudinal bearing frame for the ankle joint 9, a transverse bearing frame for the ankle joint 10, and a lower leg connecting rod 11.

[0020] like Figure 2 As shown, the radiation-resistant outer shell 19 enables humanoid robots to conduct inspections in nuclear power plants with high radiation levels without damaging internal components.

[0021] To provide a clearer and more vivid understanding of this invention, a six-legged robot is used as an example to illustrate the application of two modes to the robot, as described below. Figure 3 :

[0022] Reference Figure 3 The power transmission device rotates, driving the lead screw roller nuts 13 and 18 to rotate, which in turn causes the lead screw 12 to perform push-pull motion. By changing the working mode of the motor, the transmission direction of the lead screw can be changed, enabling the humanoid leg to achieve different movement purposes to adapt to complex terrain and task requirements. This fully utilizes the control advantages of the planetary roller lead screw.

[0023] Example

[0024] Reference Figure 1 , 2A humanoid robot leg structure based on a planetary roller screw is characterized by the following: the structure includes a hip joint motor frame 1, a thigh link 2, a screw sleeve 3, a joint bearing 4, a sleeve fixing component 5, a fisheye bearing 6, a sleeve bearing connecting frame 7, a push rod bearing frame 8, an ankle joint longitudinal bearing frame 9, an ankle joint transverse bearing frame 10, a lower leg link 11, a screw 12, screw roller nuts 13 and 18, a nut fixing sleeve 17, a motor housing 14, a thrust roller bearing 16, a motor base 15, and a radiation-resistant material housing 19; the thigh link 2 is powered by bearings. The device output shaft is connected; the power transmission device and the motor frame 1 are fixed to each other; the lead screw sleeve 3 is connected to the thigh connecting rod 2 through the sleeve bearing connecting frame 7 and the bearing; the thigh connecting rod 2 is connected to the calf connecting rod 11 through the bearing; the calf part of the lead screw structure is the same as the lead screw sleeve 3, and is fixed to the calf connecting rod 11 through the sleeve fixing piece 5 and the fish eye bearing, and the bottom of the lead screw is connected to the foot plate through the fish eye bearing; the lower end of the calf connecting rod 11 is fixed to the ankle joint longitudinal bearing frame 9 and the bearing; the ankle joint longitudinal bearing frame 9 is fixed to the ankle joint transverse bearing frame 10, and the lower end of the ankle joint transverse bearing frame is connected to the foot plate.

[0025] The inner sides of the lead screw roller nuts 13 and 18 are threaded to the outer side of the lead screw 12; the nut fixing sleeve 17 is fixed to the motor housing 14; a thrust roller bearing 16 is embedded between the motor base 15 and the motor housing 14; the motor base 15 and the lead screw roller nut 18 are coaxially fixed.

[0026] The power output device consists of a motor, a gearbox, and an encoder, which are connected in sequence to output power.

[0027] Finally, it should be noted that the above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. Therefore, although this specification has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the present invention, and all technical solutions and improvements that do not depart from the spirit and scope of the invention should be covered within the scope of the claims of the present invention.

Claims

1. A humanoid robot leg structure based on a planetary roller screw, characterized by: The structure comprises a hip joint motor frame (1), a thigh connecting rod (2), a screw sleeve (3), a joint bearing (4), a sleeve fixing piece (5), a fisheye bearing (6), a sleeve bearing connecting frame (7), a push rod bearing frame (8), an ankle joint longitudinal bearing frame (9), an ankle joint transverse bearing frame (10), a calf connecting rod (11), a planetary roller screw (12), screw roller nuts (13, 18), a nut fixing sleeve (17), a motor housing (14), a thrust needle bearing (16), a motor base (15) and an anti-radiation material shell (19); The thigh connecting rod (2) is connected with the power output shaft through a bearing; the power transmission device is fixed with the motor frame (1); the screw sleeve (3) is connected with the thigh connecting rod (2) through the sleeve bearing connecting frame (7) and a bearing; the thigh connecting rod (2) is connected with the calf connecting rod (11) through the joint bearing (4); the screw structure of the calf part is the same as the screw sleeve (3), and the screw sleeve (3) and the fisheye bearing (6) are fixed on the calf connecting rod (11) through the sleeve fixing piece (5); the bottom of the planetary roller screw (12) is connected with the foot plate through the fisheye bearing (6); the ankle joint longitudinal bearing frame (9) and a bearing are fixed on the lower end of the calf connecting rod (11); the ankle joint longitudinal bearing frame (9) is fixed with the ankle joint transverse bearing frame (10), and the lower end of the ankle joint transverse bearing frame (10) is connected with the foot plate; The rollers of the planetary roller screw (12) roll in the thread grooves on the inside of the screw roller nuts (13, 18), and the push-pull movement of the screw is realized through the meshing of the threads; the planetary roller screw (12) is located in the screw sleeve (3) and cooperates with the screw roller nuts (13, 18), and is fixedly connected with the motor housing (14) through the nut fixing sleeve (17); the thrust needle bearing (16) is embedded between the motor base (15) and the motor housing (14); the motor base (15) is coaxially fixed with the screw roller nut (18), the main body assembly of the humanoid robot leg structure based on the planetary roller screw is completed, and the outside of the main body of the humanoid robot leg structure based on the planetary roller screw is covered by the anti-radiation material shell (19); The power output device is composed of a motor, a gear box and an encoder, and the motor, the gear box and the encoder are sequentially connected for power output; by changing the working mode of the motor, the transmission direction of the planetary roller screw (12) is changed, so that the humanoid leg achieves different movement purposes, so as to adapt to complex terrains and task requirements. When the humanoid robot is walking, the hip joint power supply device rotates, driving the thigh link (2) to rotate; inside the sleeve (3), the power transmission device rotates, driving the screw roller nut (13, 18) to rotate, and then making the planetary roller screw (12) do a push-pull motion; in the screw push-pull motion, the sleeve bearing connecting frame (7) and the push rod bearing frame (8) fixed bearings will rotate relative to the support; the planetary roller screw (12) push-pull motion drives the calf link (11) to rotate; in the small leg screw structure, when the two screw structures move at the same speed, the footboard pitch motion is driven, and the ankle joint longitudinal bearing frame (9) fixed bearing rotates relative to the support; when the two screw structures move in opposite directions, the footboard roll motion is driven, and the ankle joint transverse bearing frame (10) fixed bearing rotates relative to the support; when the power output device is working, the power is transmitted to the screw roller nut (13, 18) through the gear box and encoder, and the rotation of the screw roller nut (13, 18) drives the planetary roller screw (12) to do a push-pull motion; the push-pull motion of the planetary roller screw (12) is transmitted to the calf link (11) through the sleeve bearing connecting frame (7) and the push rod bearing frame (8), thereby realizing the movement of the calf; when the two screw structures move at the same speed, the footboard pitch motion is generated; when the two screw structures move in opposite directions, the footboard roll motion is generated; by changing the working mode of the power output device, the transmission direction of the screw is changed, and the leg of the humanoid robot achieves different motion purposes to adapt to complex terrain and task needs; through the control of the power output device, the planetary roller screw (12) can realize different transmission directions and speed changes, so that the leg of the humanoid robot has high flexibility and adaptability in walking, climbing, crossing obstacles and complex terrain; in the walking process, the leg adjusts the push-pull motion of the screw to realize different gaits and postures to adapt to different ground conditions; in the patrol task of the nuclear plant, it is necessary to walk in narrow passages, stairs and uneven ground; through the control of the power output device, the planetary roller screw (12) realizes the push-pull motion of the screw, so that the leg can flexibly adjust the gait in the walking process; when the humanoid robot needs to cross a pipeline or an obstacle, the leg adjusts the push-pull motion of the screw to realize the pitch and roll motion of the footboard, so as to cross the obstacle and ensure the smooth progress of the patrol task; in the complex environment of the nuclear plant, the humanoid robot needs to have the ability to avoid obstacles; through the efficient transmission of the planetary roller screw (12), the leg of the humanoid robot quickly adjusts the posture when encountering obstacles; when the humanoid robot detects an obstacle in front, the leg adjusts the push-pull motion of the screw to make the footboard roll, thereby changing the walking direction and avoiding the obstacle.

2. The humanoid robot leg structure based on planetary roller screw according to claim 1, characterized in that: The anti-radiation material shell (19) enables the humanoid robot to patrol in the high-radiation nuclear plant without damaging the internal elements.

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