Traveling mechanism and robot

Abstract

The invention relates to a walking mechanism which comprises a hip base and a foot support and further comprises four sets of leg assemblies, the leg assemblies are rotationally connected to the hip base, and rotating shafts of the leg assemblies are parallel. One end of each foot assembly is rotationally connected with the corresponding foot support; the two sets of foot assemblies are the first foot assembly and the second foot assembly, the first foot assembly is rotationally connected with the first leg assembly and the second leg assembly, and the second foot assembly is rotationally connected with the fourth leg assembly. The coupling assembly is rotationally connected with the first foot assembly, the second foot assembly and the third foot assembly; and telescopic assemblies are arranged in the three groups of moving assemblies with two connecting points. According to the walking mechanism, the mass is close to the hip base, so that the rotational inertia of the whole walking mechanism is reduced, the system rigidity is improved, the walking mechanism is suitable for occasions with high stability requirements and high precision requirements, the motion precision and the feedback precision can be improved, and the control performance and adaptability of a robot are improved.

Description

Technical Field

[0001] The present invention relates to the field of robot driving technology, in particular to a walking mechanism and a robot. Background Art

[0002] In the field of robotics, particularly humanoid robots, exoskeletons, and rehabilitation robots, the lower limb structure plays a key role in supporting, moving, and executing complex tasks. Currently, mainstream robotic lower limbs mostly utilize serial joint structures (e.g., hip-knee-ankle rotary joints in series). This structure offers a simple design, a large workspace, and a relatively straightforward kinematic model. However, serial structures have significant inherent drawbacks: the positioning accuracy and stiffness of the end effector gradually decrease with distance from the base. Drive errors and joint flexibility are amplified at the end of the kinematic chain, causing deformation and vibration at the foot end when subjected to impact loads or performing delicate manipulations, compromising motion stability and accuracy. Furthermore, the load capacity of serial structures is limited by the weakest joint, making it difficult to achieve high stiffness and dynamic performance while maintaining lightweight design. Therefore, a new structural solution is urgently needed to fundamentally improve the stiffness, precision, and load capacity of lower limb end effectors.

[0003] Humanoid robots are robots that possess typical human characteristics, can adapt to complex environments, and perform multitasking. They represent the epitome of the robotics field. The development of complete robots and their components will drive rapid growth in the upstream and downstream supply chains, providing a strong impetus for the development of humanoid robots. Humanoid robots mimic human walking through the movement of their legs, offering greater terrain adaptability than wheeled or quadrupedal robots. However, they also consume significant energy to maintain balance while walking. Compared to wheeled or quadrupedal structures, they suffer from lower stability when standing and walking, and the two-legged form lacks advantages in load-bearing capacity, locomotion performance, and stability. Therefore, there is significant room for improvement in the leg-based walking mechanism of humanoid robots.

[0004] Currently, the most common leg drive system for humanoid robots is a rotary electric joint system. This system offers advantages such as high torque density and lightweight construction, effectively enhancing the robot's mobility. Its structure generally consists of a set of rotary drive motors located in the thigh and calf, respectively. The thigh and calf, and the calf and foot, are connected via revolute joints such as bearings. Through a connecting rod structure, separate motors drive the thigh, calf, and foot structures to rotate independently. Through specialized motion planning and control, this set of rotary drive motors can enable balanced standing and walking in humanoid robots. Most current commercially available systems require multiple motors located in both the thigh and calf. Each motor rotates at a different angle during robot movement. This design inevitably requires the placement of rotary motors below the knee joint. During walking, the calf swings rapidly, and these motors contribute to the robot's inertial forces, increasing its energy consumption.

[0005] As mentioned above, humanoid robots equipped with rotary drive motor systems have multiple motors deployed in both the thigh and calf, which shifts the center of mass of the legs downward. This increases the robot's energy consumption, reduces its endurance, and limits the legs' high-speed burst capabilities. Summary of the Invention

[0006] The present application aims to provide a new structural solution for a walking mechanism, thereby solving the problems of large moment of inertia and insufficient dynamic performance of existing serial joints.

[0007] The present application provides a walking mechanism, comprising: Hip base, Foot support, Four groups of leg assemblies, the leg assemblies being rotatably connected to the hip base, the rotation axes of the leg assemblies being parallel, the four groups of leg assemblies being leg assembly one, leg assembly two, leg assembly three, and leg assembly four; Two sets of foot assemblies, one end of each set of foot assemblies being rotatably connected to the foot support; the two sets of foot assemblies are foot assembly 1 and foot assembly 2 respectively; The foot component 1 is rotatably connected to the leg component 1 and the leg component 2 respectively, and the foot component 2 is rotatably connected to the leg component 4.

[0008] A coupling assembly, the coupling assembly being rotatably connected to the foot assembly 1, the foot assembly 2, and the leg assembly 3; In the set of motion assemblies formed by all the leg assemblies, all the foot assemblies, and all the coupling assemblies, there are three groups of motion assemblies with two connection points, in which telescopic assemblies are provided to achieve controlled change of the distance between the two connection points of the motion assemblies; The rotation axes of the leg assembly, the foot assembly and the coupling assembly are all parallel.

[0009] Preferably, the telescopic component is arranged on the leg component one, the leg component two, and the leg component four.

[0010] Preferably, the telescopic assembly is a linear motor, and the linear motor can self-lock when there is no power output.

[0011] Preferably, a first rotating device and a second rotating device are provided above the hip base, and the rotation axes of the first rotating device and the second rotating device are orthogonal.

[0012] Preferably, the first rotating device and the second rotating device are both orthogonal to the rotation axis of the motion component.

[0013] The present application also provides a robot equipped with two sets of alternatingly driven walking mechanisms as described above.

[0014] The walking mechanism utilizes various kinematic components that are rotatably connected in a specific manner, forming a series of kinematic chains between the hip base and the foot support. These kinematic chains are coupled through coupling assemblies and other components, resulting in three degrees of freedom for the entire device. Three telescopic actuators are also provided to achieve defined, humanoid lower limb-driven motion within the walking mechanism. The movement of mass closer to the hip base reduces the walking mechanism's moment of inertia and increases system rigidity, making it suitable for applications requiring high stability and precision. This improves motion and feedback accuracy, enhancing the robot's control performance and adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the walking mechanism 1 of the present application; Figure 2 This is a schematic diagram of the structure of the robot of this application.

[0016] In the picture: 1: Walking mechanism; 11: Hip base; 12: Leg assembly; 121: Leg assembly one; 122: Leg assembly two; 123: Leg assembly three; 124: Leg assembly four; 13: Foot assembly; 131: Foot assembly one; 132: Foot assembly two; 14: Foot support; 16: Rotating device two; 17: Rotating device one; 18: Telescopic assembly; 19: Coupling assembly. DETAILED DESCRIPTION

[0017] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. In this specification, the size ratios in the drawings do not represent the actual size ratios, but are only used to reflect the relative positional relationship and connection relationship between the various components. Components with the same name or the same number represent similar or identical structures and are only for illustrative purposes.

[0018] Figure 1 This is a schematic diagram of the structure of the walking mechanism 1 of the present application. It comprises a hip base 11 for mounting walking components, and multiple leg links 12 rotatably connected to the hip base 11, with their rotation axes being parallel, allowing the multiple hip bases 11 to rotate within parallel planes. The multiple hip bases 11 are combined to simulate the forward and backward rotation of the legs relative to the hip base 11 about the lateral rotation axis. There are four groups of hip bases 11, which, for ease of description, may be designated as leg assembly 1 121, leg assembly 2 122, leg assembly 3 123, and leg assembly 4 124.

[0019] Two sets of foot links 13 are provided, each with one end pivotally connected to the foot support 14. For ease of description, they may be designated as foot assembly 1 131 and foot assembly 2 132. Foot assembly 2 131 is pivotally connected to leg assembly 1 121 and leg assembly 2 122, respectively. Another set of foot assembly 2 132 is pivotally connected to leg assembly 4 124. In other words, a chain motion mechanism is formed, running from the hip base 11 through leg assembly 4 124 and foot assembly 2 132 to the foot support 14. This also forms a composite chain motion mechanism, which drives foot assembly 1 131 through the hip base 11, through foot assembly 1 131, and through foot assembly 2 132, to the foot support 14. However, the internal motion states of the aforementioned chain motion mechanisms and composite chain motion mechanisms are uncertain, and there is no kinematic connection between the two chain motion mechanisms at this point.

[0020] The primary purpose of connecting both foot assembly 131 and foot assembly 2 132 to foot support 14 is to drive the corresponding movement of foot support 14 through the coordinated movement of foot assembly 131 and foot assembly 2 132. To achieve this, a coupling assembly 19 is provided. Coupling assembly 19 connects both foot assembly 131 and foot assembly 2 132 to coordinate their movement, thereby driving foot support 14. Specifically, coupling assembly 19 is rotationally connected to foot assembly 131 at one location, to foot assembly 2 132 at another location, and to leg assembly 3 123 at a third location.

[0021] In any component with two connection points among these motion components, a telescopic component 18 is set to realize the controlled change of the distance between the two connection points of the motion component. Such telescopic components 18 should be set in three groups, correspondingly arranged on three different motion components. According to the above-mentioned structural record, the components that meet the requirements of having two connection points are four leg components 12, that is, any one of leg component one 121, leg component two 122, leg component three 123 and leg component four 124. Three linear motors are centrally connected in parallel to the thigh and hip joint, and the three degrees of freedom of the hip joint, leg, thigh and foot are realized through the cooperation of the three motors. At this time, due to the large weight of the telescopic component 18, it is beneficial to realize the low moment of inertia of the walking mechanism 1 after it is moved up to the leg component 12, thereby optimizing the control of the walking mechanism 1 and improving the control accuracy. The three linear motors can realize standing, squatting and walking of the robot, and the rotation of the ankle is more conducive to the analog control of the foot end point. Parallel drive enhances leg stability, and collaborative drive also brings better energy efficiency; the foot is equipped with a built-in plantar force sensor, which separates the instep and the sole of the foot. By detecting the feedback force when the feet touch the ground, the motor output is adjusted in time to form a closed-loop feedback system, thereby enhancing the legs' adaptability to different terrain conditions.

[0022] The telescopic component 18 preferably adopts a linear motor, which has a self-locking characteristic. When the motor is not powered on, the legs remain upright. The motion component with more than two connection points is not necessarily rod-shaped. It can have various different planar structures depending on the spatial plane position of its specific connection points. On this basis, the mechanical mechanism design can be carried out based on the step optimization method to reduce material costs, mass and inertia, and increase rigidity. Moreover, such a parallel mechanism design reduces additional connecting rods, improves the rigidity of the system, and is suitable for tasks with high stability requirements, such as industrial handling robots. By reducing additional connecting rods and connection points, the drive mechanism is simpler and more reliable, the failure rate is reduced, and the maintainability of the system is improved. Therefore, it can be suitable for applications with larger loads. The more rigid structure can withstand larger loads and is suitable for robots that walk or climb with loads.

[0023] Furthermore, in such a walking mechanism, the axes of rotation of the aforementioned revolving joints are parallel, so that the entire running mechanism is confined to move within the same parallel plane. In actual robots, this is generally considered to be the plane of oscillation in the forward and backward directions. The telescopic assembly 18 can be a linear motor, a hydraulic power unit, or other form of power unit.

[0024] Furthermore, two orthogonal rotating motors, namely Rotary Unit 17 and Rotary Unit 2 16, are mounted above the upper mounting base 11. The rotation axes of Rotary Unit 17 and Rotary Unit 2 16 are orthogonal, and the rotation axes of Rotary Unit 17 and Rotary Unit 2 16 are also orthogonal to the rotation axes of any connection points of the walking mechanism 1. This controls the lateral swing and external rotation of the entire walking mechanism 1.

[0025] The walking mechanism has a high center of mass, which reduces lateral swing and improves the robot's stability at higher walking speeds. Furthermore, by shifting the heavier drive components upward, the leg's inertia is reduced, minimizing resistance during movement and improving the robot's walking speed and stability. Furthermore, topological optimization reduces leg mass and energy consumption, improving the robot's energy efficiency and endurance. Furthermore, increased leg rigidity, enhanced motion precision and feedback, and enhanced controllability and adaptability are achieved.

[0026] This application also provides a Figure 2 The humanoid robot shown has two sets of walking mechanisms 1 arranged side by side, and the two sets of walking mechanisms 1 are alternately driven to imitate the walking of the lower limbs of the human body.

[0027] The above content only describes the preferred embodiments of the present invention and does not limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solution of the present invention by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present invention.

Claims

1. A walking mechanism, characterized in that: include: Hip base (11), Foot support (14), Four groups of leg assemblies (12), the leg assemblies (12) are rotatably connected to the hip base (11), the rotation axes of the leg assemblies (12) are parallel, and the four groups of leg assemblies (12) are leg assembly one (121), leg assembly two (122), leg assembly three (123) and leg assembly four (124); Two groups of foot assemblies (13), one end of each of the two groups of foot assemblies (13) is rotatably connected to the foot support (14); the two groups of foot assemblies (13) are foot assembly 1 (131) and foot assembly 2 (132); The foot component 1 (131) is rotatably connected to the leg component 1 (121) and the leg component 2 (122), respectively, and the foot component 2 (132) is rotatably connected to the leg component 4 (124). A coupling assembly (19), wherein the coupling assembly (19) is rotatably connected to the foot assembly 1 (131), the foot assembly 2 (132) and the leg assembly 3 (123); In the set of motion assemblies formed by all the leg assemblies (12), all the foot assemblies (13) and all the coupling assemblies (19), there are three groups of motion assemblies with two connection points, in which telescopic assemblies (18) are provided to achieve controlled change of the distance between the two connection points of the motion assemblies; The rotation axes of the leg assembly (12), the foot assembly (13) and the coupling assembly (19) are all parallel.

2. The walking mechanism according to claim 1, wherein: The telescopic component (18) is arranged on the leg component one (121), the leg component two (122), and the leg component four (124).

3. The walking mechanism according to claim 1, wherein: The telescopic component (18) is a linear motor, and the linear motor can self-lock when there is no power output.

4. The walking mechanism according to claim 1, wherein: A rotating device 1 (17) and a rotating device 2 (16) are provided above the hip base (11), and the rotating axes of the rotating device 1 (17) and the rotating device 2 (16) are orthogonal.

5. The walking mechanism according to claim 4, characterized in that: The first rotating device (17) and the second rotating device (16) are both orthogonal to the rotation axis of the motion component.

6. A robot, characterized in that: The utility model is equipped with two sets of alternately driven walking mechanisms as described in any one of claims 1 to 5.

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