An underactuated, flexible bipedal hopping robot

Abstract

The application provides an underactuated flexible biped jumping robot, which comprises a robot body and a flexible leg structure arranged on the robot body, the flexible leg structure comprising a hip, a thigh, a shank and a foot, one end of the hip being connected with the robot body, the other end of the hip being connected with the thigh, one end of the shank being connected with the thigh, the other end of the shank being connected with the foot. The application adopts a stepping motor as a driving source of the robot, and the driving force is large and the response speed is fast; the spring and the cable in the leg structure simulate the muscle effect, the spring can not only play a role of buffering and shock absorption when the robot lands, but also can realize the energy storage function, and the energy utilization efficiency of the robot is improved; the biped robot drives the counterweight mounted thereon through the linear motor in the body, adjusts the gravity center position of the biped robot, and makes the robot obtain a stable posture in the movement process.

Description

Technical Field

[0001] This invention relates to the field of robotics, and in particular to an underactuated flexible bipedal jumping robot. Background Technology

[0002] In missions such as wilderness exploration, disaster relief, and interstellar exploration, the complexity and unknown nature of the external environment place high demands on the unstructured environment adaptability and obstacle-crossing capabilities of reconnaissance robots. While traditional wheeled robots boast high mobility, their operation is highly dependent on the surrounding environment, and their obstacle-crossing ability is insufficient. Traditional rigid quadruped robots, compared to wheeled robots, possess stronger obstacle-crossing capabilities, but their mobility is far inferior, and due to their structural characteristics, their self-buffering capacity is weak. Furthermore, since traditional robots are mostly fully actuated, their control systems are relatively complex to ensure normal operation. Summary of the Invention

[0003] To address the problems of complex structure and control system and poor obstacle-crossing ability of reconnaissance robots, this invention proposes an underactuated flexible bipedal jumping robot.

[0004] An underactuated flexible bipedal jumping robot includes a robot body and a flexible leg structure. The flexible leg structure is disposed on the robot body and includes a hip, a thigh, a lower leg, and a foot. The hip is connected to the robot body and the thigh, the thigh is connected to the hip and the lower leg, and the lower leg is connected to the hip, the thigh, and the foot.

[0005] Furthermore, the robot body includes a chassis, a stepper motor, a winding wheel, a linear motor, and a counterweight; the stepper motors are symmetrically arranged on both sides of the chassis, the winding wheel is connected to the output shaft of the stepper motor, the counterweight is mounted on the linear motor, and the linear motor is located inside the chassis.

[0006] Furthermore, the hip includes a hip bone, a spring rod, a hip spring, and a spring bracket; the bottom of the spring rod has a small hole, the hip bone is rigidly connected to the robot body, the spring bracket is vertically fixed on the hip bone, the hip spring is installed in the slot of the spring bracket, the spring rod is installed in the hip spring, and the top of the spring rod abuts against the top of the hip spring.

[0007] Furthermore, the thigh includes a drive cable, a large pulley cable for the thigh joint, a large pulley for the thigh joint, a thigh connecting shaft, the femur, and a small pulley for the thigh joint. One end of the drive cable is wound around the winding reel, and the other end is wound around the small pulley for the thigh joint. The large pulley for the thigh joint has a hollow fan-shaped structure with small holes on its side wall. One end of the large pulley cable for the thigh joint is bound to the small hole on the side wall of the large pulley for the thigh joint, and the other end is bound to the small hole at the bottom of the spring pressure rod. The large pulley for the thigh joint, the small pulley for the thigh joint, and the femur are fixedly connected to the thigh connecting shaft. The femur and the hip bone are rotatably connected through the thigh connecting shaft.

[0008] Furthermore, the lower leg includes a lower leg pulley cable, a lower leg joint pulley, a lower leg tibia, a lower leg fibula, a tibia connecting shaft, and a lower leg joint connecting shaft; the two ends of the lower leg pulley cable are respectively wound and connected to the thigh joint pulley and the lower leg joint pulley; the lower leg joint pulley and the lower leg tibia are fixedly connected through the tibia connecting shaft; the lower leg fibula is rotatably connected to the lower leg tibia through the lower leg joint connecting shaft; and the lower leg tibia and the thigh femur are rotatably connected through the tibia connecting shaft.

[0009] Furthermore, the fibula of the lower leg includes a first connecting bracket, a second connecting bracket, a fibular joint connecting shaft, a fibular spring, a fibular connecting shaft, and a connecting shaft nut; the first connecting bracket and the second connecting bracket have small holes at their top centers, the fibular connecting shaft passes through the two small holes, the lower part of the fibular connecting shaft is provided with a thread adapted to the connecting shaft nut, the connecting shaft nut is threadedly connected to the lower part of the fibular connecting shaft, and the fibular spring is sleeved on the fibular connecting shaft between the second connecting bracket and the connecting shaft nut; the first connecting bracket is rotatably connected to the hip bone through the fibular joint connecting shaft, and the second connecting bracket is rotatably connected to the tibia of the lower leg through the lower leg joint connecting shaft.

[0010] Furthermore, the foot includes a foot joint pulley, a foot joint axis, a foot body, a foot torsion spring, and a foot pulley cable; the foot joint pulley and the foot body are fixedly connected via the foot joint axis; one end of the foot pulley cable is wound around the foot joint pulley, and the other end is wound around the lower leg joint pulley; the central groove of the foot torsion spring is installed in the groove of the foot joint axis, and its outer ring is installed in the mounting hole of the lower leg tibia by its own expansion and compression; the foot body and the lower leg tibia are rotatably connected via the foot joint axis.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: the leg structure is simple, the failure rate is low, and the weight is light. The spring in the leg structure can not only play a role in buffering and shock absorption when the robot lands, but also realize the energy storage and release function, which greatly improves the energy utilization efficiency of the robot. The bipedal robot uses a linear motor in the main body to drive the counterweight installed on it to adjust the center of gravity of the bipedal robot, so that the robot can obtain a stable posture during movement. Attached Figure Description

[0012] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0013] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention;

[0014] Figure 2 This is a schematic diagram of the components in an embodiment of the present invention;

[0015] Figure 3 This is a schematic diagram of the flexible leg structure according to an embodiment of the present invention;

[0016] Figure 4 This is a schematic diagram of the main structure of an embodiment of the present invention;

[0017] Figure 5 This is a schematic diagram of the hip structure according to an embodiment of the present invention;

[0018] Figure 6 This is an exploded view of the spring bracket assembly according to an embodiment of the present invention;

[0019] Figure 7 This is a front view of the thigh structure according to an embodiment of the present invention;

[0020] Figure 8 This is a side view of the thigh structure according to an embodiment of the present invention;

[0021] Figure 9 This is a front view of the lower leg structure according to an embodiment of the present invention;

[0022] Figure 10 This is a side view of the lower leg structure according to an embodiment of the present invention;

[0023] Figure 11 This is a schematic diagram of the fibular structure of the lower leg according to an embodiment of the present invention;

[0024] Figure 12 This is an exploded view of the foot assembly according to an embodiment of the present invention;

[0025] Figure 13 This is a schematic diagram of the foot structure according to an embodiment of the present invention;

[0026] Figure 14 This is a schematic diagram of the structure of the large pulley at the thigh joint in an embodiment of the present invention;

[0027] Figure 15 This is a schematic diagram of the thigh joint pulley structure according to an embodiment of the present invention;

[0028] Figure 16 This is a schematic diagram of the lower leg joint pulley structure according to an embodiment of the present invention;

[0029] Figure 17 This is a schematic diagram of the foot joint pulley structure according to an embodiment of the present invention;

[0030] Figure 18 This is a schematic diagram of the foot joint axis structure according to an embodiment of the present invention;

[0031] Figure 19 This is a schematic diagram of the foot torsion spring structure according to an embodiment of the present invention;

[0032] Figure 20 This is a schematic diagram of the driving principle of the flexible leg in an embodiment of the present invention;

[0033] Figure 21 This is a schematic diagram of the retracted state of the flexible leg in an embodiment of the present invention;

[0034] Figure 22 This is a schematic diagram of the extended state of the flexible leg in an embodiment of the present invention.

[0035] Explanation of reference numerals in the attached figures:

[0036] 1: Main body; 2: Hip; 3: Thigh; 4: Lower leg; 5: Foot; 6: Chassis; 7: Stepper motor; 8: Winding reel; 9: Drive cable; 10: Linear motor; 11: Counterweight; 12: Hip bone; 13: Spring rod; 14: Hip spring; 15: Spring support; 16: Large pulley cable of thigh joint; 17: Large pulley of thigh joint; 18: Thigh connecting shaft; 19: Femur; 20: Small pulley of thigh joint; 21: Lower leg 22: Lower leg joint pulley; 23: Lower leg tibia; 24: Lower leg fibula; 25: Tibia connecting shaft; 26: Lower leg joint connecting shaft; 27: First connecting bracket; 28: Second connecting bracket; 29: Fibular joint connecting shaft; 30: Fibular spring; 31: Fibular connecting shaft; 32: Connecting shaft nut; 33: Foot joint pulley; 34: Foot joint shaft; 35: Foot body; 36: Foot torsion spring; 37: Foot pulley cable. Detailed Implementation

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

[0038] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," 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 this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0039] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0040] like Figure 1 , Figure 2 and Figure 3 As shown, the present invention provides an underactuated flexible bipedal jumping robot, including a robot body and a flexible leg structure. The flexible leg structure is disposed on the robot body 1 and includes a hip 2, a thigh 3, a calf 4, and a foot 5. The hip 2 is connected to the body 1 and the thigh 3 respectively, the thigh 3 is connected to the hip 2 and the calf 4 respectively, and the calf 4 is connected to the hip 2, the thigh 3, and the foot 5 respectively.

[0041] like Figure 4 As shown, the main body of the robot includes a chassis 6, a stepper motor 7, a winding wheel 8, a linear motor 10, and a counterweight 11. The stepper motor 7 is symmetrically arranged on both sides of the chassis 6. The winding wheel 8 is connected to the output shaft of the stepper motor 7. The counterweight 11 is mounted on the linear motor 10, and the linear motor 10 is located inside the chassis 6.

[0042] like Figure 5 and Figure 6 As shown, the hip includes a hip bone 12, a spring rod 13, a hip spring 14, and a spring bracket 15; the spring bracket 15 is vertically fixed on the hip bone 12, the hip spring 14 is installed in the slot of the spring bracket 15, the spring rod 13 is installed in the hip spring 14, and the top of the spring rod 13 abuts against the top of the hip spring 14, and the hip 12 is rigidly connected to the robot body 1.

[0043] like Figure 7 and Figure 8 As shown, the robot thigh 3 includes a drive cable 9, a large thigh joint pulley cable 16, a large thigh joint pulley 17, a thigh connecting shaft 18, a femur 19, and a small thigh joint pulley 20. One end of the drive cable 9 is wound and connected to a winding wheel 8, and the other end is wound and connected to the small thigh joint pulley 20. The large thigh joint pulley 17 has a hollow fan-shaped structure with small holes on its side wall. One end of the large thigh joint pulley cable 16 is bound and connected to the small hole on the side wall of the large thigh joint pulley 17, and the other end is bound and connected to the small hole at the bottom of the spring pressure rod 13. The large thigh joint pulley 17, the small thigh joint pulley 20, and the femur 19 are fixedly connected to the thigh connecting shaft 18. The femur 19 and the hip bone 12 are rotatably connected through the thigh connecting shaft 18.

[0044] like Figure 9 and Figure 10 As shown, the robot's lower leg 4 includes a lower leg pulley cable 21, a lower leg joint pulley 22, a lower leg tibia 23, a lower leg fibula 24, a tibia connecting shaft 25, and a lower leg joint connecting shaft 26. The two ends of the lower leg pulley cable 21 are respectively wound and connected to the thigh joint pulley 20 and the lower leg joint pulley 22. The lower leg joint pulley 22 and the lower leg tibia 23 are fixedly connected through the tibia connecting shaft 25. The lower leg fibula 24 is rotatably connected to the lower leg tibia 23 through the lower leg joint connecting shaft 26. The lower leg tibia 23 is rotatably connected to the thigh femur 19 through the tibia connecting shaft 25.

[0045] like Figure 11 As shown, the fibula of the lower leg includes a first connecting bracket 27, a second connecting bracket 28, a fibular joint connecting shaft 29, a fibular spring 30, a fibular connecting shaft 31, and a connecting shaft nut 32. The first connecting bracket 27 and the second connecting bracket 28 have small holes at their top centers. The fibular connecting shaft 31 passes through the two small holes. The lower part of the fibular connecting shaft 31 is provided with a thread that matches the connecting shaft nut 32. The connecting shaft nut 32 is threadedly connected to the lower part of the fibular connecting shaft 31. The fibular spring 30 is sleeved on the fibular connecting shaft 31 between the second connecting bracket 28 and the connecting shaft nut 32. The first connecting bracket 27 is rotatably connected to the hip bone 12 through the fibular joint connecting shaft 29, and the second connecting bracket 28 is rotatably connected to the tibia of the lower leg 23 through the lower leg joint connecting shaft 26.

[0046] like Figure 12 As shown, the robot's foot includes a foot joint pulley 33, a foot joint shaft 34, a foot body 35, a foot torsion spring 36, and a foot pulley cable 37. The foot joint pulley 33 and the foot body 35 are fixedly connected by the foot joint shaft 34. One end of the foot pulley cable 37 is wound around the foot joint pulley 33, and the other end is wound around the lower leg joint pulley 22. The central groove of the foot torsion spring 36 is installed in the slot of the foot joint shaft 34, and its outer ring is installed in the mounting hole of the lower leg tibia 23 by its own expansion and compression. The foot body 35 and the lower leg tibia 23 are rotatably connected by the foot joint shaft 34.

[0047] The movement mechanism of the flexible leg in this invention is as follows:

[0048] like Figure 20 As shown, when the flexible leg contracts, the winding wheel 8 rotates in the same direction as illustrated. The winding wheel 8 drives the cable 9 to wind and contract, causing the large thigh joint pulley 17 and the small thigh joint pulley 20 to rotate in the direction shown. The large thigh joint pulley 17 pulls the spring pressure rod 13 through the large thigh joint pulley cable 16, thus compressing the hip spring 14. The small thigh joint pulley 20 pulls the lower leg joint pulley 22 through the lower leg pulley cable 21, rotating it in the direction shown, thus compressing the fibular spring 30. The lower leg joint pulley 22 then pulls the foot joint pulley 33 through the foot pulley cable 37, causing the foot joint pulley 33 to rotate in the direction shown, simultaneously driving the foot torsion spring 36 to rotate and tighten. At this point, the contraction action of the flexible leg structure is completed. Figure 21 As shown; when the flexible leg relaxes, the winding wheel 8 reverses to release the drive cable 9, and the compressed springs are released. This completes the reverse process described above, achieving the relaxation effect. Figure 22 As shown, by repeatedly performing contraction and relaxation movements, the robot can achieve jumping and walking.

[0049] The motion mechanism of an underactuated flexible bipedal jumping robot is as follows:

[0050] While the robot moves based on its flexible leg structure, the linear motor inside the main body operates, adjusting the position of the counterweight to adjust the robot's overall center of gravity, enabling the robot to maintain a relatively stable state when jumping and landing.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An underactuated, flexible bipedal jumping robot, characterized in that, The system includes a robot body (1) and a flexible leg structure. The flexible leg structure is disposed on the robot body (1) and includes a hip (2), a thigh (3), a calf (4), and a foot (5). The hip (2) is connected to the body (1) and the thigh (3) respectively. The thigh (3) is connected to the hip (2) and the calf (4) respectively. The calf (4) is connected to the hip (2), the thigh (3), and the foot (5) respectively. The hip (2) includes a hip bone (12), a spring rod (13), a hip spring (14), and a spring bracket (15); the bottom of the spring rod (13) has a small hole, the hip bone (12) is rigidly connected to the robot body (1), the spring bracket (15) is vertically fixed on the hip bone (12), the hip spring (14) is installed in the slot of the spring bracket (15), the spring rod (13) is installed in the hip spring (14), and the top of the spring rod (13) abuts against the top of the hip spring (14); The thigh (3) includes a drive cable (9), a large pulley cable (16) for the thigh joint, a large pulley (17) for the thigh joint, a connecting shaft (18) for the thigh, a femur (19) for the thigh, and a small pulley (20) for the thigh joint. One end of the drive cable (9) is set on a winding wheel (8) on the robot body (1), and the other end is wound and connected to the small pulley (20) for the thigh joint. The large pulley (17) for the thigh joint has a hollow fan-shaped structure with small holes on its side wall. One end of the large pulley cable (16) for the thigh joint is bound to the small hole on the side wall of the large pulley (17) for the thigh joint, and the other end is bound to the small hole at the bottom of the spring pressure rod (13). The large pulley (17) for the thigh joint, the small pulley (20) for the thigh joint, and the femur (19) for the thigh are fixedly connected to the connecting shaft (18). The femur (19) for the thigh and the hip bone (12) are rotatably connected through the connecting shaft (18). The lower leg (4) includes a lower leg pulley cable (21), a lower leg joint pulley (22), a lower leg tibia (23), a lower leg fibula (24), a tibial connecting shaft (25), and a lower leg joint connecting shaft (26). The two ends of the lower leg pulley cable (21) are respectively wound and connected to the thigh joint pulley (20) and the lower leg joint pulley (22). The lower leg joint pulley (22) and the lower leg tibia (23) are fixedly connected through the tibial connecting shaft (25). The lower leg fibula (24) is rotatably connected to the lower leg tibia (23) through the lower leg joint connecting shaft (26). The lower leg tibia (23) and the thigh femur (19) are rotatably connected through the tibial connecting shaft (25). The fibula (24) of the lower leg includes a first connecting bracket (27), a second connecting bracket (28), a fibular joint connecting shaft (29), a fibular spring (30), a fibular connecting shaft (31), and a connecting shaft nut (32). The first connecting bracket (27) and the second connecting bracket (28) have small holes at their top centers. The fibular connecting shaft (31) passes through the two small holes. The lower part of the fibular connecting shaft (31) is provided with a thread that matches the connecting shaft nut (32). The connecting shaft nut (32) is threadedly connected to the lower part of the fibular connecting shaft (31). The fibular spring (30) is sleeved on the fibular connecting shaft (31) between the second connecting bracket (28) and the connecting shaft nut (32). The first connecting bracket (27) is rotatably connected to the hip bone (12) through the fibular joint connecting shaft (29). The second connecting bracket (28) is rotatably connected to the tibia (23) of the lower leg through the lower leg joint connecting shaft (26).

2. The underactuated flexible bipedal jumping robot according to claim 1, characterized in that, The robot body (1) includes a chassis (6), a stepper motor (7), a winding wheel (8), a linear motor (10), and a counterweight (11). The stepper motor (7) is symmetrically arranged on both sides of the chassis (6). The winding wheel (8) is connected to the output shaft of the stepper motor (7). The counterweight (11) is installed on the linear motor (10). The linear motor (10) is located inside the chassis (6).

3. The underactuated flexible bipedal jumping robot according to claim 1, characterized in that, The foot (5) includes a foot joint pulley (33), a foot joint shaft (34), a foot body (35), a foot torsion spring (36), and a foot pulley cable (37). The foot joint pulley (33) and the foot body (35) are fixedly connected by the foot joint shaft (34). One end of the foot pulley cable (37) is wound around the foot joint pulley (33), and the other end is wound around the lower leg joint pulley (22). The central groove of the foot torsion spring (36) is installed in the slot of the foot joint shaft (34), and its outer ring is installed in the mounting hole of the lower leg tibia (23) by its own expansion and compression. The foot body (35) and the lower leg tibia (23) are rotatably connected by the foot joint shaft (34).

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