Robot link mechanism and robot

Abstract

The utility model relates to robot technical field, especially a robot connecting rod mechanism and robot, including thigh support pole, shank support pole, drive connecting disc, first movable connecting rod and second movable connecting rod, one end of thigh support pole is connected with shank support pole, drive connecting disc sets up at one end of thigh support pole away from shank support pole, one end of first movable connecting rod is rotatively connected with drive connecting disc, both ends of first movable connecting rod are provided with first connecting element and second connecting element respectively, one end of first movable connecting rod is connected with second movable connecting rod through first connecting element, and the other end is connected with second movable connecting rod through second connecting element to form movable four connecting rod structure. Compared with the problem that single connecting rod structure swing angle is limited, through parallel four connecting rod mechanism that double connecting rod constitutes, the swing range of shank support pole relative to thigh support pole is increased.

Description

Technical Field

[0001] This utility model relates to the field of robot technology, and in particular to a robot linkage mechanism and a robot. Background Technology

[0002] Wheeled-legged robots have become a research hotspot in the field of mobile robotics in recent years. They combine the advantages of wheeled robots, such as high speed and efficiency, with the advantages of legged robots, such as strong obstacle-crossing ability and good terrain adaptability, enabling stable and efficient movement in complex environments. Their leg structure typically consists of thighs, lower legs, and wheels, and the joint design between the thighs and lower legs directly determines the robot's mobility and terrain adaptability.

[0003] In existing technologies, wheeled robots often employ a hinged joint structure between the thigh and lower leg, using a motor to drive relative oscillation to simulate the flexion and extension movements of a biological leg. However, some designs, in order to simplify the structure and reduce weight, use a single-link structure as the transmission method between the thigh and lower leg. This structure typically connects the thigh and lower leg with only a single rigid link, resulting in a simple transmission path, but it has significant disadvantages in practical applications.

[0004] First, the strong geometric constraints of single-link structures limit the swing angle of the lower leg relative to the thigh, preventing the wide range of flexion and extension movements possible with multi-link or flexible joints. This significantly reduces the robot's obstacle-crossing ability and gait flexibility when facing complex terrain (such as steep slopes, high steps, or deep pits). Second, single-link structures are prone to significant stress concentration during movement, which can lead to fatigue damage at the connection points over long-term operation, affecting system reliability and lifespan. Utility Model Content

[0005] To address the aforementioned issues, this invention, compared to the limited swing angle of a single-link structure, utilizes a parallel four-bar linkage composed of two links to increase the swing range of the lower leg support relative to the thigh support. This allows the robot's legs to achieve greater flexibility in flexion and extension angles, significantly enhancing the robot's obstacle-crossing ability and adaptability when facing complex terrains such as steep slopes and high steps.

[0006] The technical solution adopted by this utility model is as follows: a robot linkage mechanism, including a thigh support rod, a lower leg support rod, a drive connecting plate, a first movable link, and a second movable link. One end of the thigh support rod is connected to the lower leg support rod. The drive connecting plate is located at the end of the thigh support rod away from the lower leg support rod. One end of the first movable link is rotatably connected to the drive connecting plate. The two ends of the first movable link are respectively provided with a first connecting element and a second connecting element. One end of the first movable link is connected to the second movable link through the first connecting element, and the other end is connected to the second movable link through the second connecting element, so as to form a movable four-bar structure. During movement, the drive connecting plate drives the first movable link to move under the action of the power source. The first movable link drives the lower leg support rod to move at the connection point of the thigh support rod. At the same time, under the action of the first connecting element and the second connecting element, the second movable link moves parallel to the first movable link.

[0007] A further improvement to the above solution is that a first shaft and a second shaft are respectively provided at both ends of the thigh support rod. The first shaft is used to connect to the drive connecting plate and is concentrically arranged with the drive connecting plate. The second shaft is rotatably connected to one end of the calf support rod.

[0008] A further improvement to the above scheme is that a drive wheel set is provided at the end of the lower leg support rod away from the thigh support rod, which is used to drive the robot linkage mechanism to move.

[0009] A further improvement to the above solution is that the drive connecting disk is provided with a first eccentric connecting shaft, and the drive connecting disk is connected to the first movable connecting rod through the first eccentric connecting shaft.

[0010] A further improvement to the above scheme is that the lower leg support rod is provided with a third shaft core, the third shaft core being concentrically arranged with the second shaft core, the lower leg support rod is provided with a second eccentric connecting shaft, the second eccentric connecting shaft being arranged at one end of the lower leg support rod with the third shaft core as its axis, and one end of the first movable connecting rod being connected to the second eccentric connecting shaft.

[0011] A further improvement to the above solution is that the first connecting element is provided with a first arc surface, and the axis of the first arc surface is coaxial with the axis of the drive connecting disk.

[0012] A further improvement to the above scheme is that the second connecting element is provided with a second arc surface, and the second arc surface is coaxial with the axis of the third shaft.

[0013] A further improvement to the above scheme is that one side of the first connecting element is pivotally connected to the first movable link, and the other side is pivotally connected to the second movable link.

[0014] A further improvement to the above scheme is that one side of the second connecting element is pivotally connected to the first movable link, and the other side is pivotally connected to the second movable link.

[0015] A robot, including the aforementioned robot linkage mechanism.

[0016] The beneficial effects of this utility model are: Compared to existing robot joint linkage structures, this invention introduces a movable parallel four-bar linkage structure by combining a first movable link and a second movable link, effectively overcoming the inherent defects of traditional single-link transmission methods. Compared to the limited swing angle of single-link structures, the parallel four-bar linkage mechanism with two links increases the swing range of the lower leg support relative to the thigh support. This allows the robot's legs to achieve greater flexion and extension angles, significantly improving the robot's obstacle-crossing ability and adaptability when facing complex terrains such as steep slopes and high steps. Addressing the shortcomings of single-link structures, such as stress concentration and susceptibility to fatigue damage, this invention utilizes the motion characteristics of the parallel four-bar linkage mechanism to transform the drive load from being transmitted by a single link to being shared by two links. This effectively disperses local stress at the joint connections, avoids stress concentration, improves the load-bearing capacity and fatigue resistance of the transmission structure, thereby extending the overall service life and operational reliability of the robot mechanism. The parallel four-bar linkage mechanism ensures that the lower leg support maintains a specific parallel relationship with the drive connection plate throughout the movement, thus achieving more precise and stable motion trajectory control. This improved the robot's motion smoothness and attitude control accuracy. Attached Figure Description

[0017] Figure 1 This is a three-dimensional schematic diagram of the robot linkage mechanism of this utility model; Figure 2 for Figure 1 Front view schematic diagram of the linkage mechanism of the robot; Figure 3 for Figure 1 A schematic diagram of the active state of the linkage mechanism of the robot. Figure 4 for Figure 1 A schematic diagram of the active state of the linkage mechanism of the robot. Figure 5 for Figure 1 A schematic diagram of the active state of the linkage mechanism of the robot. Figure 6 for Figure 1 A schematic diagram of the explosion state of the linkage mechanism of the robot.

[0018] Explanation of reference numerals in the attached drawings: thigh support rod 1, first shaft core 11, second shaft core 12, lower leg support rod 2, drive wheel assembly 21, third shaft core 22, second eccentric connecting shaft 23, drive connecting disc 3, first eccentric connecting shaft 31, first movable connecting rod 4, first connecting element 41, first arc surface 411, second connecting element 42, second arc surface 421, second movable connecting rod 5. Detailed Implementation

[0019] To facilitate understanding of this utility model, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of this utility model are shown in the drawings. However, this utility model can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this utility model.

[0020] It should be noted that when a component is said to be "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Figures 1-5 As shown, in one embodiment of this utility model, a robot linkage mechanism is disclosed, including a thigh support rod 1, a lower leg support rod 2, a drive connecting plate 3, a first movable link 4, and a second movable link 5. One end of the thigh support rod 1 is rotatably connected to the lower leg support rod 2. The drive connecting plate 3 is located at the end of the thigh support rod 1 away from the lower leg support rod 2. One end of the first movable link 4 is rotatably connected to the drive connecting plate 3. The two ends of the first movable link 4 are respectively provided with a first connecting element 41 and a second connecting element 42. One end of the first movable link 4 is connected to the second movable link 5 through the first connecting element 41, and the other end is connected to the second movable link 5 through the second connecting element 42, forming a movable four-bar linkage structure. During movement, the drive connecting plate 3 drives the first movable link 4 to move under the action of a power source. The first movable link 4 drives the lower leg support rod 2 to move at the connection point with the thigh support rod 1. At the same time, under the action of the first connecting element 41 and the second connecting element 42, the second movable link 5 moves parallel to the first movable link 4. Furthermore, both the first connecting element 41 and the second connecting element 42 are rotatably connected to the first movable connecting rod 4 and the second movable connecting rod 5.

[0022] Specifically, this embodiment uses a movable parallel four-bar linkage structure formed by the first movable link 4 and the second movable link 5, effectively overcoming the inherent defects of traditional single-link transmission methods. Compared to the limited swing angle of a single-link structure, the parallel four-bar linkage mechanism with two links increases the swing range of the lower leg support 2 relative to the thigh support 1. This allows the robot's legs to achieve more flexible movements with greater flexion and extension angles, greatly improving the robot's obstacle-crossing ability and adaptability when facing complex terrains such as steep slopes and high steps. Addressing the shortcomings of single-link structures, such as stress concentration and susceptibility to fatigue damage, the parallel four-bar linkage mechanism further utilizes its motion characteristics to transform the driving load from being transmitted by a single link to being shared by two links. This effectively disperses local stress at joint connections, avoids stress concentration, improves the load-bearing capacity and fatigue resistance of the transmission structure, and thus extends the overall service life and operational reliability of the robot mechanism. The parallel four-bar linkage mechanism ensures that the lower leg support 2 maintains a specific parallel relationship with the drive connecting plate 3 throughout the movement, thereby achieving more precise and stable motion trajectory control. This improved the robot's motion smoothness and attitude control accuracy.

[0023] In this embodiment, a first shaft core 11 and a second shaft core 12 are respectively provided at both ends of the thigh support rod 1. The first shaft core 11 is used to connect to the drive connecting plate 3 and is concentrically arranged with the drive connecting plate 3. The second shaft core 12 is rotatably connected to one end of the lower leg support rod 2. Specifically, on the one hand, the first shaft core 11 and the drive connecting plate 3 are concentrically arranged, forming a stable rotational pivot. This ensures that the driving force is transmitted directly and accurately from the connecting rod to the connecting plate, minimizing radial runout and assembly accumulation errors during the movement process, keeping the rotation center of the drive connecting plate 3 stable, and providing extremely high positioning repeatability for the end effector. On the other hand, the second shaft core 12, as the rotational connection point between the thigh support rod 1 and the lower leg support rod 2, defines the motion transmission chain: the rotation of the lower leg support rod 2 is converted into the swing of the thigh support rod 1 through the second shaft core 12, and then drives the drive connecting plate 3 through the first shaft core 11. This achieves decoupling of the motion function, allowing the drive source to be arranged in a more optimized position without directly affecting the compactness of the end effector's activity space.

[0024] Furthermore, a drive wheel assembly 21 is provided at the end of the lower leg support 2 away from the thigh support 1 to drive the movement of the robot's linkage mechanism. This allows the application of a double-link mechanism to a wheeled robot. Specifically, when the robot needs to move, the drive wheel assembly 21 acts as the active wheel, providing power and enabling efficient movement on flat ground. When encountering complex terrain such as steps or ditches, the double-link mechanism functions as a flexible mechanical leg. By controlling the relative movement of the thigh support 1 and the lower leg support 2, the entire "wheeled leg" unit can actively lift, cross obstacles, or adjust its posture to maintain vehicle stability.

[0025] In this embodiment, the drive connecting disk 3 is provided with a first eccentric connecting shaft 31, which is located on the periphery of the drive connecting disk 3 and is connected to the first movable link 4 through the first eccentric connecting shaft 31. Specifically, the axis of the first eccentric connecting shaft 31 does not coincide with the rotation center (i.e., the first shaft core 11) of the drive connecting disk 3, meaning that the drive of the first movable link 4 on the drive connecting disk 3 is not a direct concentric rotation, but rather introduces an additional offset. When the double-link mechanism moves, the oscillation of the first movable link 4 is transformed into a composite motion of the drive connecting disk 3 through the eccentric shaft, which includes not only rotation but may also include a small, controlled translation component. By designing the size and direction of the eccentricity, the motion trajectory of the drive connecting disk 3 can be optimized to more accurately fit a specific working path, such as achieving a translation closer to a straight line or a more complex curved motion, without adding an additional drive joint.

[0026] In this embodiment, the lower leg support 2 is provided with a third shaft core 22, which is concentrically arranged with the second shaft core 12. The lower leg support 2 is also provided with a second eccentric connecting shaft 23, which is arranged around the third shaft core 22 at the periphery of the lower leg support 2, and one end of the first movable connecting rod 4 is connected to the second eccentric connecting shaft 23. Specifically, the concentric arrangement of the third shaft core 22 and the second shaft core 12 enhances the rigidity and precision of the rotational connection between the thigh support 1 and the lower leg support 2. The collinear structure of the third shaft core 22 and the second shaft core 12 effectively distributes the load bending moment, enhances the joint's resistance to eccentric loads, and ensures the stability of power transmission. The second eccentric connecting shaft 23 is eccentrically arranged with the third shaft core 22 (i.e., the rotation center of the entire lower leg support 2) as the reference, so that the driving point of the first movable connecting rod 4 has a fixed offset from the rotation center of the lower leg support 2. When the lower leg support 2 moves, it synchronously drives the second eccentric connecting shaft 23 to perform circular motion. Since the driving point is eccentric, the input obtained by the first moving link 4 is no longer angular displacement, but a complex motion with superimposed displacement components.

[0027] In this embodiment, the first connecting element 41 is provided with a first arc surface 411, the axis of which is coaxial with the axis of the drive connecting disk 3. The second connecting element 42 is provided with a second arc surface 421, the axis of which is coaxial with the axis of the third shaft core 22. Specifically, the first arc surface 411 is coaxial with the axis of the drive connecting disk 3, meaning that the arc surface essentially constitutes part of the rotation trajectory of the drive connecting disk 3 or a precision guide surface. When the drive connecting disk 3 rotates relative to the first connecting element 41, the first arc surface 411 can provide a continuous, smooth, and coaxial contact or guide reference, effectively eliminating the radial runout or unexpected wobble that may occur in the drive connecting disk 3, ensuring that its rotation axis is always stable, thereby ensuring the positioning accuracy of the end effector installed on it. The second arc surface 421 is coaxial with the third shaft core 22 (i.e., the rotation center of the lower leg support 2), and its function is to provide auxiliary guidance and constraint for the rotation of the lower leg support 2. It can compensate for movement gaps that may be caused by machining and assembly errors, and also enhance the deformation resistance and movement stability of the entire second joint when bearing load.

[0028] In this embodiment, one side of the first connecting element 41 is pivotally connected to the first movable link 4, and the other side is pivotally connected to the second movable link 5. One side of the second connecting element 42 is pivotally connected to the first movable link 4, and the other side is pivotally connected to the second movable link 5. Specifically, the first connecting element 41 and the second connecting element 42 serve as two "opposite sides" of this parallelogram, while the first movable link 4 and the second movable link 5 serve as the other two "opposite sides." According to the motion principle of the parallelogram mechanism, when the mechanism moves, the first connecting element 41 and the second connecting element 42 will always maintain a parallel relationship. This enhances the attitude stability of the drive connecting plate 3, ensuring that it always maintains a preset orientation during complex movements, such as always being parallel to the base or a certain reference plane, which is crucial for many tasks that require the end effector to maintain a specific angle. Secondly, the symmetrical double-link drive structure achieves effective force diversion and balance. The load or torque applied to the drive connecting plate 3 can be borne jointly by the first movable link 4 and the second movable link 5, avoiding the huge bending moment that may be generated by single link drive, thereby reducing the stress inside the component and improving the overall structural rigidity and load-bearing capacity.

[0029] In another embodiment, a robot employs the aforementioned linkage mechanism. Through the concentric third shaft core 22 on the lower leg support 2 and the eccentric second eccentric connecting shaft 23, complex motion output under a single drive source is achieved, resulting in flexible movement and a large workspace. Simultaneously, the parallelogram closed-loop structure formed by the pivotal connections of the first and second connecting elements 42 to the first and second movable connecting rods 5 on both sides ensures extremely high posture stability and load-bearing capacity of the end effector during movement. Furthermore, the first arc surface 411 on the first connecting element 41 is coaxial with the drive connecting disk 3, and the second arc surface 421 on the second connecting element 42 is coaxial with the third shaft core 22, together forming a precise motion guidance system that effectively eliminates motion gaps and swaying. This allows the robot to maintain excellent dynamic performance and repeatability even in high-speed, high-load, or high-precision operation scenarios.

[0030] The above embodiments only illustrate several implementation methods of this utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A robot linkage mechanism, characterized in that: The device includes a thigh support rod, a calf support rod, a drive connecting plate, a first movable link, and a second movable link. One end of the thigh support rod is connected to the calf support rod, and the drive connecting plate is mounted on the thigh support rod. One end of the first movable link is rotatably connected to the drive connecting plate, and both ends of the first movable link are respectively provided with a first connecting element and a second connecting element. One end of the first movable link is connected to the second movable link through the first connecting element, and the other end is connected to the second movable link through the second connecting element, forming a movable four-bar structure. During movement, the drive connecting plate drives the first movable link to move under the action of a power source. The first movable link drives the calf support rod to move at the connection point with the thigh support rod. At the same time, under the action of the first and second connecting elements, the second movable link moves parallel to the first movable link.

2. The robot linkage mechanism according to claim 1, characterized in that: The thigh support rod has a first shaft and a second shaft at both ends. The first shaft is used to connect to the drive connecting plate and is concentric with the axis of the drive connecting plate. The second shaft is rotatably connected to one end of the calf support rod.

3. The robot linkage mechanism according to claim 1, characterized in that: The lower leg support rod is equipped with a drive wheel set at the end away from the thigh support rod, which is used to drive the robot's linkage mechanism to move.

4. The robot linkage mechanism according to claim 1, characterized in that: The drive connecting plate is provided with a first eccentric connecting shaft, and the drive connecting plate is connected to the first movable connecting rod through the first eccentric connecting shaft.

5. The robot linkage mechanism according to claim 2, characterized in that: The lower leg support rod is provided with a third shaft core, which is concentric with the second shaft core. The lower leg support rod is provided with a second eccentric connecting shaft, which is located at one end of the lower leg support rod with the third shaft core as its axis. One end of the first movable connecting rod is connected to the second eccentric connecting shaft.

6. The robot linkage mechanism according to claim 5, characterized in that: The first connecting element is provided with a first arc surface, and the axis of the first arc surface is coaxial with the axis of the drive connecting disk.

7. The robot linkage mechanism according to claim 6, characterized in that: The second connecting element is provided with a second arc surface, which is coaxial with the axis of the third shaft.

8. A robot, characterized in that: Includes the robot linkage mechanism as described in any one of claims 1 to 7.

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