Wheel and foot switching device suitable for robot

Abstract

The invention provides a wheel and foot switching device suitable for a robot. The wheel and foot switching device comprises an instep bearing structure, a front wheel driving assembly, a rear wheel driven assembly and a sole movement assembly. The front-wheel driving assembly comprises a front-wheel motor and a front wheel; a front wheel motor and a foot wheel switching motor are mounted in the instep bearing structure; the sole movement assembly is mounted at the bottom of the instep bearing structure through a connecting rod mechanism; the front wheel is located outside the instep bearing structure and rotationally connected with an output shaft of the front wheel motor. A rear wheel in the rear wheel driven assembly is rotationally mounted on the instep bearing structure; in the wheel type movement mode, the front wheel motor drives the front wheel to rotate and drives the rear wheel to be driven, and the foot wheel switching motor drives the connecting rod mechanism to drive the sole movement assembly to be retracted into the instep bearing structure; in the foot type movement mode, the foot wheel switching motor drives the connecting rod mechanism to drive the sole movement assembly to extend out of the bottom of the instep bearing structure. The adaptive capacity and motion performance of the robot in diversified terrain environments are improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of legged robots, and particularly relates to a leg-wheel switching device suitable for a legged robot. BACKGROUND

[0002] Mobile robots are divided into wheel type and foot type structures. Wheel type robots have the advantages of high motion efficiency and fast marching speed, but their passing performance is obviously limited when facing obstacles such as steps, trenches or soft ground. Foot type robots have good adaptability to complex terrain and strong obstacle crossing performance, but they have problems such as low motion efficiency, high energy consumption and complex control.

[0003] When mobile robots perform tasks in an increasingly complex real-world environment, they face severe challenges from diversified terrains. Flat ground requires efficient and fast moving ability, while rugged and unstructured terrain requires excellent obstacle crossing and adaptability. Traditional single mobile mode robots often cannot meet both requirements.

[0004] At present, most leg-wheel switching devices have the disadvantages of complex structure and slow switching speed, and cannot meet the demand for fast and reliable switching of different motion modes in actual applications. Therefore, a leg-wheel switching device with compact structure and convenient and efficient motion mode switching is designed. SUMMARY

[0005] The technical problem to be solved by the application is to provide a leg-wheel switching device suitable for a robot, which is applied to the lower part of the robot below the calf, and can realize fast and stable switching between the wheel type motion mode and the foot type motion mode, thereby significantly improving the adaptability and motion performance of the robot in diversified terrain environments.

[0006] The technical solution adopted by the application is a leg-wheel switching device suitable for a robot, which comprises a dorsal bearing structure, a front wheel driving assembly, a rear wheel driven assembly and a sole motion assembly.

[0007] The front wheel driving assembly comprises a front wheel motor and a front wheel, the dorsal bearing structure is internally provided with the front wheel motor and a foot-wheel switching motor, the sole motion assembly is installed at the bottom of the dorsal bearing structure through a connecting rod mechanism, and the front wheel is externally connected with the output shaft of the front wheel motor. The rear wheel in the rear wheel driven assembly is rotatably installed on the dorsal bearing structure. In the wheel type motion mode, the front wheel motor drives the front wheel to rotate, the rear wheel is driven, and the foot-wheel switching motor drives the connecting rod mechanism to drive the sole motion assembly to be retracted into the dorsal bearing structure. In the foot type motion mode, the foot-wheel switching motor drives the connecting rod mechanism to drive the sole motion assembly to extend from the bottom of the dorsal bearing structure.

[0008] Further, the front wheel driving assembly further comprises a motor support and a shaft sleeve.

[0009] The motor support is a U-shaped structure, connected with the mounting plane at the top of the inner cavity of the instep bearing structure; the front wheel motor is fixed on the motor support; the two output shafts of the front wheel motor are connected with an axle sleeve respectively; the axle sleeve is internally processed with a key groove structure matched with the output shaft of the front wheel motor; one end of each axle sleeve is fixedly connected with the output shaft of the front wheel motor in the circumferential direction through a flat key, and is axially positioned by a screw; the other end of the axle sleeve is connected with the front wheel.

[0010] Further, the rear wheel driven assembly comprises a rear wheel shaft, an elastic retainer ring and rear wheels, the rear wheel shaft extends out of the rear wheel assembly mounting hole on the instep bearing structure at both ends, and the two rear wheels are mounted at both ends of the rear wheel shaft, with a bearing mounted in the hub center hole to realize rotational fitting connection with the rear wheel shaft; the rear wheel shaft is axially limited by shaft shoulder positioning and the elastic retainer ring.

[0011] Further, the foot sole movement assembly comprises a left front rod, a right front rod, a left rear rod, a right rear rod, a foot sole and a foot wheel switching motor; one end of the left front rod and the right front rod is hingedly connected with the foot sole through a pin shaft respectively; the other end of the left front rod and the right front rod is hingedly connected with the foot sole movement assembly front end rod mounting hole on the instep bearing structure through a pin shaft; one end of the left rear rod and the right rear rod is torque transmission connected with the two output shafts of the foot wheel switching motor through a key respectively; the other end of the left rear rod and the right rear rod is hingedly connected with the foot sole through a pin shaft; the left front rod, the right front rod, the left rear rod and the right rear rod form a four-bar linkage mechanism.

[0012] Further, an axle sleeve is mounted on the pin shaft and axially limited by an elastic retainer ring.

[0013] Further, the front end and the rear end of the foot sole are respectively provided with a connecting seat connected with the left front rod, the right front rod, the left rear rod and the right rear rod, and a bushing is embedded in the mounting hole of the connecting seat to reduce friction.

[0014] Further, the foot wheel switching motor drives the left rear rod and the right connecting rod to rotate, and synchronously drives the left front rod and the right front rod to rotate in the same direction; a front stopper and a rear stopper are respectively mounted on the movement trajectory path of the foot sole movement assembly; when the four-bar linkage mechanism rotates in the counterclockwise direction and contacts the front stopper, the foot sole is retracted and switched to the wheel type movement mode; when the four-bar linkage mechanism rotates in the clockwise direction to contact the rear stopper, and the left front rod, the right front rod, the left rear rod and the right rear rod are respectively perpendicular to the foot sole, the foot sole lands and is switched to the foot type movement mode.

[0015] Further, a buffer rubber pad is arranged at the contact part of the left front rod, the right front rod, the left rear rod, the right rear rod, the front stopper or the rear stopper.

[0016] Further, the wheel-foot switching device is fixedly installed at the end of the small leg of the robot through the mounting hole of the instep bearing structure.

[0017] In the foot mode, the robot can realize obstacle crossing and walking by controlling the rotation angle and speed parameters of the leg driving motor, cooperating with the contact action of the foot sole with the ground and the coordinated movement of the leg.

[0018] Compared with the prior art, the present application has the following advantages:

[0019] (1) The present application realizes rapid and stable conversion between the wheel mode and the foot mode, significantly improves the adaptability and versatility of the mobile mechanism in diversified terrain environments, and effectively expands the application scenarios.

[0020] (2) The front wheel driving assembly of the present application adopts a motor driving mode, and the motor support, shaft sleeve and front rubber wheel and other key components are optimized in design, ensuring stable and reliable power output of the wheel mode; the rear wheel driven device adopts a rubber wheel structure equipped with bearings, which is simple and reasonable in design, significantly reduces power loss and improves motion efficiency.

[0021] (3) Based on the motion characteristics of the parallelogram mechanism, the present application adds a limiting block to the foot sole movement assembly to ensure the accuracy and stability of the motion mode switching process. The various components of the whole wheel-foot switching device are connected by standardized connection methods and material selection, which not only facilitates assembly, disassembly and maintenance operations, but also significantly enhances the overall maintainability and service life of the mechanism, showing its outstanding technical advantages and market application potential. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a schematic diagram of the overall structure of the wheel-foot switching device;

[0023] Figure 2 is a schematic diagram of the motion mode switching process;

[0024] Figure 3 is a schematic diagram of the foot sole movement assembly structure;

[0025] Figure 4 is a schematic diagram of the instep bearing structure. DETAILED DESCRIPTION

[0026] The present application will be described in conjunction with the accompanying drawings.

[0027] As Figure 1 shown, the present application provides a wheel-foot switching device suitable for a robot, which includes an instep bearing structure 1, a front wheel driving assembly 2, a rear wheel driven assembly 3 and a foot sole movement assembly 4.

[0028] (1) Instep bearing structure

[0029] As shown in Figure 4 , the instep bearing structure 1 is connected with the robot calf end as the support component of the wheel-foot switching device, and the installation space of the driving motor is arranged inside. On the side of the structure, the front wheel assembly mounting hole 13, the rear wheel assembly mounting hole 14, and the instep movement assembly front end rod mounting hole 11 and the instep movement assembly rear end rod mounting hole 12 are arranged to ensure the stable connection with the front wheel driving assembly 2, the rear wheel driven assembly 3, and the instep movement assembly 4.

[0030] (2) Front wheel driving assembly

[0031] As shown in Figure 2 , the front wheel driving assembly 2 is composed of a front wheel motor 21, a motor support 22, a shaft sleeve, and a front wheel.

[0032] The motor support 22 is designed as a U-shaped structure, which is firmly connected with the mounting plane 17 of the instep bearing structure 1 through bolts, and the front wheel motor 21 is fixed on the motor support 22 through bolts.

[0033] The shaft sleeve is internally machined with a key groove structure matched with the output shaft of the front wheel motor 21. The two output shafts of the front wheel motor 21 are respectively connected with a shaft sleeve; one end of the shaft sleeve is fixedly connected with the output shaft of the front wheel motor 21 in the circumferential direction through a key, and is axially positioned by a screw to prevent the shaft sleeve from axially moving and circumferentially rotating on the output shaft of the motor, thereby ensuring the accuracy and reliability of power transmission; the other end is provided with an internally threaded hole structure, which is detachably connected with the front wheel through bolts, thereby facilitating subsequent maintenance and component replacement.

[0034] (3) Rear wheel driven assembly

[0035] The rear axle 34 is respectively extended from the rear wheel assembly mounting hole 14 at both ends, and the two rear wheels of the rear wheel driven assembly 3 are symmetrically installed at both ends of the rear axle 34, with bearings arranged in the hub center holes to realize rotational fitting connection with the rear axle 34. The rear axle 34 is axially limited by shaft shoulder positioning and elastic retainer 35, which effectively prevents the rear wheel from axially moving during operation. In the wheeled movement mode, the rotational driving force of the front wheel is transmitted through the ground friction force to drive the rear wheel to realize synchronous rotational movement, thereby realizing the wheeled movement function of the mechanism.

[0036] (4) Instep movement assembly

[0037] As shown in Figure 3 , the instep movement assembly 4 is composed of a rod structure, an instep 46, and a foot wheel switching motor 41.

[0038] Rod structure: the left front rod 42, the right front rod 43, the left rear rod 44, the right rear rod 45 are provided with connecting holes at both ends, which are used to realize the hinged connection with the sole movement assembly and the instep bearing structure 1. One end of the left front rod 42 and the right front rod 43 is hingedly connected with the front end connecting seat of the sole through a pin shaft 47; the other end of the left front rod 42 and the right front rod 43 is hingedly connected with the front end rod piece mounting hole 11 of the sole movement assembly through a pin shaft 47; a shaft sleeve 49 is installed on the pin shaft 47, and is axially limited by an elastic check ring 35. One end of the left rear rod 44 and the right rear rod 45 is connected with the two output shafts of the foot wheel switching motor 41 through a key to realize torque transmission connection; the other end of the left rear rod 44 and the right rear rod 45 is hingedly connected with the rear end connecting seat of the sole. The four rods form a parallelogram mechanism, and based on the geometric motion characteristics of the parallelogram, the stability and synchronization in the movement process are ensured.

[0039] The front end and the rear end of the sole 46 are respectively provided with connecting seats connected with the left front rod, the right front rod, the left rear rod and the right rear rod. Wear-resistant bushings 48 are embedded in the mounting holes of the connecting seats. Through the antifriction effect of the bushings 48, the wear degree between the pin shaft 47 and the mounting hole is significantly reduced, and the reliability and service life of the connecting part are effectively improved.

[0040] The foot wheel switching motor 41 drives the left rear rod 44 and the right connecting rod 45 to rotate through the key connection, and based on the motion transmission characteristics of the parallelogram mechanism, the left front rod 42 and the right front rod 43 are synchronously driven to rotate in the same direction. On the movement trajectory path of the sole movement assembly, a front stop block 15 and a rear stop block 16 are respectively installed. When the four connecting rods rotate in the counterclockwise direction and contact the front stop block 15, the sole 46 is retracted, and the device is switched to the wheel type movement mode; when the four connecting rods rotate in the clockwise direction to contact the rear stop block 16, and the connecting rod is perpendicular to the sole 46, the sole 46 falls to the ground, and the device is switched to the foot type movement mode. In addition, a buffer rubber pad is arranged at the contact part of the connecting rod and the stop block, which can effectively absorb the impact force generated in the movement mode switching process, and has a good protection effect on the mechanism parts.

[0041] In the specific application stage, first, the connecting bolt is used to fix and install the wheel-foot switching device of the application on the end of the robot's lower leg through the mounting hole of the instep bearing structure 1.

[0042] When the mobile device is in the flat road working condition, the foot wheel switching motor 41 drives the left rear rod 44 and the right rear rod 45 to synchronously rotate counterclockwise, and then drives the sole part to move forward until the sole movement assembly contacts the front stop block 15, at which time the sole is retracted, and the device is switched to the wheel type movement mode. Subsequently, the controller starts the front wheel motor 21, and accurately adjusts the motor speed according to the actual movement demand, drives the front wheel to rotate, and drives the rear wheel to synchronously rotate through the ground friction force, realizes the fast and efficient wheel type movement of the device.

[0043] When the mobile device encounters complex terrain (such as steps, obstacles, etc.), the foot wheel switching motor 41 drives the left rear rod 44 and the right rear rod 45 to rotate synchronously clockwise, drives the foot sole 46 to rotate clockwise, until the connecting rod contacts the rear stop block 16 and the connecting rod is perpendicular to the foot sole 46, at this time the foot sole 46 falls to the ground, and the device switches to the foot mode. In the foot mode, by accurately controlling the rotation angle and speed parameters of the leg driving motor, cooperating with the contact action of the foot sole 46 with the ground and the coordinated movement of the leg, the obstacle crossing and complex terrain passing functions of the device are realized.

[0044] In the whole movement process, the movement mode can be flexibly and accurately switched by the controller according to real-time terrain detection data, so as to achieve the best movement effect.

[0045] The part not described in detail in the present application belongs to the known technology of those skilled in the art.

Claims

1. A wheel-foot switching device suitable for a robot, characterized in that: It comprises an instep bearing structure (1), a front wheel driving assembly (2), a rear wheel driven assembly (3) and a sole movement assembly (4); The front wheel drive assembly (2) comprises a front wheel motor (21) and a front wheel; the front wheel motor (21) and the foot wheel switching motor (41) are installed inside the instep bearing structure (1); the sole movement assembly (4) is installed at the bottom of the instep bearing structure (1) through a connecting rod mechanism; the front wheel is located outside the instep bearing structure (1) and is rotatably connected to the output shaft of the front wheel motor (21); the rear wheel in the rear wheel driven assembly (3) is rotatably installed on the instep bearing structure (1); in the wheeled motion mode, the front wheel motor (21) drives the front wheel to rotate, driving the rear wheel to follow, and the foot wheel switching motor (41) drives the connecting rod mechanism to drive the sole movement assembly (4) back into the instep bearing structure (1); in the footed motion mode, the foot wheel switching motor (41) drives the connecting rod mechanism to drive the sole movement assembly (4) to extend from the bottom of the instep bearing structure (1).

2. A wheel-foot switching device suitable for a robot according to claim 1, characterized in that: The front wheel drive assembly (2) further comprises a motor bracket (22) and a shaft sleeve; the motor bracket (22) is a U-shaped structure, connected to the mounting plane (17) at the top of the inner cavity of the instep bearing structure (1); the front wheel motor (21) is fixed on the motor bracket (22); the two output shafts of the front wheel motor (21) are respectively connected to a shaft sleeve; a keyway structure matching the output shaft of the front wheel motor (21) is machined inside the shaft sleeve; one end of each shaft sleeve is circumferentially fixedly connected to the output shaft of the front wheel motor (21) through a flat key, and is axially positioned by a screw, and the other end of the shaft sleeve is connected to the front wheel.

3. A wheel-foot switching device suitable for a robot according to claim 1, characterized in that: The rear wheel driven assembly (3) comprises a rear wheel axle (34), an elastic retaining ring (35) and a rear wheel. The two ends of the rear axle (34) extend from the rear wheel assembly mounting holes (14) on the instep bearing structure (1). The two rear wheels are mounted on the two ends of the rear axle (34). The center holes of the wheel hubs are provided with bearings to realize rotational connection with the rear axle (34). The rear axle (34) is axially limited by the shaft shoulder positioning and the elastic retaining ring (35).

4. A wheel-foot switching device suitable for a robot according to claim 1, characterized in that: The foot sole motion assembly (4) comprises a left front rod (42), a right front rod (43), a left rear rod (44), a right rear rod (45), a foot sole (46), and a wheel-switching motor (41); one end of the left front rod (42) and the right front rod (43) are respectively hinged to the foot sole (46) through a pin shaft (47); the other end of the left front rod (42) and the right front rod (43) are hinged to the foot sole motion assembly front rod mounting hole (11) on the instep bearing structure (1) through a pin shaft (47); one end of the left rear rod (44) and the right rear rod (45) are respectively connected to the two output shafts of the wheel-switching motor (41) through a key for torque transmission; the other end of the left rear rod (44) and the right rear rod (45) are hinged to the foot sole (46) through a pin shaft (47); the left front rod (42), the right front rod (43), the left rear rod (44), and the right rear rod (45) form a four-bar linkage.

5. A wheel-foot switching device suitable for a robot according to claim 4, characterized in that: A shaft sleeve (49) is installed on the pin shaft (47) and is axially limited by an elastic retaining ring (35).

6. The wheel-foot switching device for a robot according to claim 5, characterized in that: The front and rear ends of the sole (46) are respectively provided with connecting seats connected to the left front rod, the right front rod, the left rear rod and the right rear rod, and the mounting holes of the connecting seats are embedded with bushings (48) to reduce friction.

7. A wheel-foot switching device suitable for a robot according to claim 6, characterized in that: The invention also includes a front block (15) and a rear block (16); the wheel switching motor (41) drives the left rear rod (44) and the right connecting rod (45) to rotate, and synchronously drives the left front rod (42) and the right front rod (43) to rotate in the same direction; the front block (15) and the rear block (16) are respectively installed on the motion track path of the sole motion component (4); when the four-bar linkage rotates in the counterclockwise direction and contacts the front block (15), the sole (46) is retracted and switched to the wheel motion mode; when the four-bar linkage rotates in the clockwise direction until it contacts the rear block (16), and the left front rod (42), the right front rod (43), the left rear rod (44) and the right rear rod (45) are respectively in a vertical state with the sole (46), the sole (46) lands and switches to the foot motion mode.

8. The wheel-foot switching device for a robot according to claim 7, characterized in that: Buffer rubber pads are provided at contact locations of the left front rod (42), the right front rod (43), the left rear rod (44), the right rear rod (45) and the front stopper (15) or the rear stopper (16).

9. A wheel-foot switching device for a robot according to any one of claims 1 to 8, characterized in that: The wheel-foot switching device is fixedly mounted on the end of the robot's calf through the mounting hole of the instep bearing structure (1).

10. The wheel-foot switching device for a robot according to claim 9, characterized in that: In the foot-type motion mode, by controlling the rotation angle and speed parameters of the robot's leg drive motor, coordinating the contact between the sole (46) and the ground and the coordinated movement of the legs, obstacle crossing and walking are achieved.

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