A wheeled, retractable obstacle-crossing robot

Abstract

This utility model provides a wheeled, legged, retractable obstacle-crossing robot, including a frame and a lower wheeled leg structure. The frame houses a control system and a motor. The wheeled leg structure includes a telescopic component and wheels. The telescopic component includes a screw structure and an extension leg that can extend and retract vertically under its control. A wheel is located at the lower part of the extension leg. The screw structure includes a screw connected to the motor, with a nut engaged on the screw. Guide rods are located on both sides of the screw, and nut seats that can slide on the guide rods are fixed on both sides of the nut. The extension leg is fixed to the nut. This application features a simple structure, good precision retention, and resistance to deformation and jamming over long-term use. Obstacle avoidance sensors on the retractable legs monitor environmental information in real time. The control system promptly raises the wheel closest to the obstacle. The remaining wheels maintain the robot's balance through closed-loop speed regulation using encoders installed inside the wheels, achieving precise speed and position control and completing asynchronous control of "single-wheel obstacle avoidance with multi-wheel cooperative posture stabilization."

Description

Technical Field

[0001] This utility model relates to the field of mobile robot technology, and in particular to a retractable wheeled obstacle-crossing robot. Background Technology

[0002] Retractable wheeled and legged obstacle-avoiding robots, as a cutting-edge branch of the mobile robotics field, combine the advantages of high-speed wheeled movement and high obstacle-crossing capability of legged robots, and have shown great application potential in industrial, rescue, and exploration scenarios in recent years. Currently, the mainstream technical approaches are divided into three categories: hydraulic / pneumatic drive, gear transmission, and spring return.

[0003] The following problems exist in the existing technology:

[0004] Firstly, some wheeled robots have complex structures and large sizes. Limited by fixed wheel diameters, their outriggers lack deformation stability and flexibility, resulting in insufficient mobility in unstructured terrain. Secondly, there is a contradiction between mechanical efficiency and precision. Traditional hydraulic / gear transmission systems suffer from high energy loss due to multi-stage transmission chains (more than 5 stages), and excessive lead screw pitch and transmission backlash lead to low positioning accuracy, making it difficult to meet the high-precision requirements of industrial scenarios. For example, Chinese invention patent CN114275071A discloses a novel deformable wheeled robot, proposing a planetary gear linkage mechanism that achieves a 300% leg length adjustment range through multi-stage reduction, but the lengthy transmission chain increases energy loss. Thirdly, there is an imbalance between dynamic response and load capacity. Spring reset mechanisms have long response times and long step response times under load, while hydraulic systems experience a sharp drop in effective load during dynamic impacts, making it impossible to balance high-speed movement and heavy-duty operations. For example, Chinese invention patent CN119117134A discloses a frameless wheeled telescopic robot. Its bidirectional obstacle-crossing scheme relies on mechanical spring reset, has a long dynamic response time, and is difficult to adapt to high-frequency obstacle avoidance requirements. Utility Model Content

[0005] To address the problems of complex structure, insufficient stability of deformable legs, low mechanical efficiency and precision, and slow response in existing obstacle avoidance robots, this utility model provides a wheel-leg retractable obstacle-crossing robot, including a frame and a wheel-leg structure at its lower part, wherein there are no fewer than 5 wheel-leg structures, and the frame is equipped with a control system and a motor, with each wheel-leg structure connected to a single motor.

[0006] The wheel-leg structure includes a telescopic component and a wheel. The telescopic component includes a lead screw structure and an extension leg that can extend and retract vertically under its control. The wheel is located at the lower part of the extension leg.

[0007] The lead screw structure includes a screw connected to the motor, a nut engaged on the screw, guide rods on both sides of the screw, and nut seats that can slide on the guide rods fixed on both sides of the nut; the extension leg is fixed to the nut; an obstacle avoidance sensor is provided on the extension leg, and an encoder is installed inside the wheel; both the obstacle avoidance sensor and the encoder are connected to the control system.

[0008] Furthermore, an upper mounting base is fixed to the upper part of the guide rod, and the upper mounting base is fixed to the vehicle frame.

[0009] Furthermore, the lead screw structure is provided with a protective shell, and a lower mounting seat is fixed to the lower part of the guide rod, and the lower mounting seat is fixed to the protective shell.

[0010] Furthermore, the lead screw structure is a ball screw structure.

[0011] Furthermore, disc spring assemblies are sleeved on both the upper and lower parts of the nut along the screw.

[0012] Furthermore, lower supports are fixed to both sides of the lower part of the extended leg, and the two lower supports are respectively fixed to the wheel axles extending from both sides of the wheel.

[0013] Furthermore, a shock-absorbing device is provided between the lower support on one side and the wheel axle.

[0014] Furthermore, the shock absorption device is a hydraulic damping shock absorber, which is connected to the lower support and the wheel axle respectively through ball joints located at its upper and lower parts.

[0015] Furthermore, the wheel includes a rim and a hub motor disposed therein, and a tire is fitted over the rim.

[0016] Compared with the prior art, this utility model has the following beneficial effects:

[0017] The telescopic component, consisting of a lead screw and extension legs, boasts a simple structure, high load-bearing capacity, and excellent precision. It is resistant to deformation and jamming even after long-term use. Combined with obstacle avoidance sensors on the telescopic legs, it monitors the surrounding environment in real time. Based on the sensor feedback, the control system promptly adjusts the leg closest to the obstacle, lifting it while the other legs continue moving forward. The remaining wheels maintain balance through closed-loop speed regulation using encoders installed within them, achieving precise speed and position control and completing asynchronous control of "single-wheel obstacle avoidance with multi-wheel cooperative posture stabilization." This obstacle avoidance method ensures that the robot can quickly coordinate its movements when encountering consecutive obstacles, sequentially lifting its legs to avoid them, achieving accurate and stable autonomous obstacle avoidance without affecting its normal movement. Furthermore, the use of hub motors to directly drive the wheels allows each wheel to be controlled independently, enabling all-wheel drive. This system can also be tightly integrated with the control system for precise power control and timely response. Attached Figure Description

[0018] Figure 1 This is the overall assembly appearance drawing of the structure of this utility model;

[0019] Figure 2 This is a general assembly line diagram of the structure of this utility model;

[0020] Figure 3 This is a schematic diagram of the wheel leg structure of this utility model;

[0021] Figure 4 This is a schematic diagram of the lead screw structure of this utility model;

[0022] Figure 5 This is a schematic diagram of the wheel of this utility model;

[0023] Figure 6 This is a schematic diagram of the shock absorption device of this utility model;

[0024] In the diagram: 1. Wheel; 2. Shock absorber; 3. Motor; 4. Frame; 5. Outer cylinder; 6. Inner cylinder; 7. Disc spring assembly; 8. Nut; 9. Screw; 10. Guide rod; 11. Bearing; 12. Nut seat; 13. Lower support; 14. Ball joint; 15. Shock absorber spring; 16. Rim; 17. Protective shell; 18. Tire; 19. Axle; 20. Upper mounting base; 21. Lower mounting base; 22. Extension leg. Detailed Implementation

[0025] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of 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 should fall within the protection scope of the present invention.

[0026] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. The terms "upper," "lower," "front," "rear," "top," "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or part referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. It should be understood that such data can be interchanged where appropriate for the embodiments of this utility model described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0027] A wheeled, retractable obstacle-crossing robot, such as Figures 1-3 As shown, the vehicle includes a frame 4 and its lower wheel leg structure. The frame 4 is equipped with a control system (not shown in the figure), a motor 3 and its mounting holes and support structure. Each wheel leg structure is connected to a single motor 3.

[0028] Generally, the frame 4 is made of aluminum alloy profile welded together, and the interior also has an electrical component fixing platform and a power supply module for powering the whole vehicle (not shown in the figure). The hollow design inside the frame is used for wiring.

[0029] like Figure 3 As shown, the wheel-leg structure includes a telescopic component and a wheel 1. The telescopic component includes a screw structure and an extension leg 22 that can extend and retract vertically under its control; the extension leg 22 is provided with a wheel 1 at its lower part.

[0030] like Figure 3 and Figure 4 As shown, the lead screw structure includes a screw 9 connected to the motor 3, a nut 8 engaged on the screw 9, guide rods 10 on both sides of the screw 9, and nut seats 12 that can slide on the guide rods 10 fixed on both sides of the nut 8; the extension leg 22 is fixed on the nut 8.

[0031] An obstacle avoidance sensor is installed on the extension leg 22, and an encoder is installed inside the wheel 1. Both the obstacle avoidance sensor and the encoder are connected to the control system. In this embodiment, each extension leg 22 is equipped with at least one obstacle avoidance sensor. The obstacle avoidance sensor includes various forms such as infrared obstacle avoidance sensor, ultrasonic sensor, lidar, and vision sensor (camera and image processing), and different obstacle avoidance sensors with different characteristics can be adapted according to the usage scenario.

[0032] The working principle of the wheeled, retractable obstacle-crossing robot in this application is as follows:

[0033] The obstacle avoidance sensors mounted on the extension leg 22 collect real-time environmental data. If there are no obstacles, all wheel-leg structures move forward on the ground. If an obstacle is detected in the direction of travel, such as when the left wheel-leg needs to be raised to pass over it, the sensor signal is transmitted to the control system via the CAN bus protocol. The industrial computer in the control system issues commands to the wheels along the direction of travel on that side in sequence as follows: pause the movement of the wheel 1 corresponding to the obstacle-crossing wheel-leg structure, and simultaneously start the corresponding motor 3. The screw 9 rotates accordingly, and by moving the nut 8 upward, the extension leg 22 fixed to the nut 8 moves upward to avoid the obstacle. During the upward movement of a single extension leg 22 to avoid the obstacle, the remaining wheels 1 maintain the vehicle's balance through closed-loop speed regulation by the encoder mounted on the wheel axle 19, providing the control system with the status data of each wheel-leg to ensure coordinated action and achieve asynchronous control of "single wheel lifting to avoid the obstacle - multi-wheel coordinated posture stabilization". After avoiding the obstacle, the extension leg 22 is lowered, causing its wheel 1 to land and restarting its movement. The subsequent wheel-leg structures that pass over the obstacle complete this series of operations under the commands of the control system, realizing successive lifting of the leg to overcome the obstacle. After the obstacle-crossing robot has completely cleared the obstacle, all wheels synchronously return to their original position. To ensure the stability of the entire robot when a single wheel is raised, the wheel structure has no fewer than five legs, ensuring that at least four other wheels are on the ground when one wheel is raised. Figure 1 As shown, this embodiment has two rows of wheel leg structures, with three wheel leg structures in each row.

[0034] As a preferred implementation method, such as Figure 3 As shown, an upper mounting base 20 is fixed to the upper part of the guide rod 10, and the upper mounting base 20 is fixed to the frame 4. Figure 3 As shown, in this embodiment, the upper mounting base 20 is L-shaped, with a guide rod 10 fixed on one side and a hole reserved for connecting the motor 26 and the screw 9; the other side is fixed to the frame 4 by bolts.

[0035] like Figure 3As shown, to prevent the obstacle avoidance robot from being affected by external factors (such as flying stones) on the lead screw structure during its movement, a protective shell 17 is provided on the outside of the lead screw structure. A lower mounting seat 21 is fixed to the lower part of the guide rod 10, and the lower mounting seat 21 is fixed to the protective shell 17. In this embodiment, the lower mounting seat 21 is L-shaped, with the guide rod 10 fixed on one side and the other side fixed to the frame 4 by bolts.

[0036] As one implementation method, such as Figure 4 As shown, the upper part of the screw 9 is connected to the motor 3 via bearing 11, and the lower part is connected to the lower mounting base 21 via bearing 11.

[0037] As a preferred implementation method, the screw structure is a ball screw structure, such as the standard part of GB / T17587.3. The ball screw structure has the advantages of low friction loss, high transmission efficiency and high precision.

[0038] As a preferred implementation method, such as Figure 4 As shown, disc spring assemblies 7 are fitted along the screw rod 9 on both the upper and lower parts of the nut 8. The disc springs have good shock absorption and damping performance, and can balance the forces between the components, reduce instability and vibration caused by torque, reduce damage to the equipment, and improve the stability and service life of the equipment.

[0039] As one implementation method, such as Figure 3 As shown, lower supports 13 are fixed on both sides of the lower part of the extension leg 22, and the two lower supports 13 are fixed to the wheel axles 19 on both sides of the extended wheel 1.

[0040] To improve driving stability and reduce impact during travel, a shock-absorbing device 2 is provided between the lower support 13 on one side and the wheel axle 19.

[0041] Specifically, such as Figure 3 and Figure 6 As shown, the shock absorber 2 is a hydraulic damping shock absorber, which is connected to the lower support 13 and the wheel axle 19 via ball joints 14 located at its upper and lower parts, respectively. The hydraulic damping shock absorber model DNM-12R can be selected, which includes an outer cylinder 5 (oil reservoir), an inner cylinder 6 (working cylinder), and a damping spring 15. This is existing technology and will not be described in detail here. The hydraulic damping shock absorber can absorb and buffer the impact force from the road surface, reduce the impact force on the wheels and other vehicle body components, reduce wear and damage to parts, and extend the service life of the vehicle.

[0042] As a preferred implementation method, such as Figure 5As shown, wheel 1 includes a rim 16 and a hub motor housed within it, with a tire 18 encased on the rim 16. By directly driving wheel 1 with the hub motor, each wheel can be independently controlled, enabling all-wheel drive. It can also be tightly integrated with the control system for precise power control and timely response. When the hub motor rotor rotates, it directly drives the rim 16 and tire 18 to rotate synchronously, eliminating the need for traditional complex mechanical transmission methods, thus improving power transmission efficiency and reducing energy loss. The hub motor can be a waterproof digital motor (model DS3218).

[0043] The above description is merely a preferred embodiment of this utility model and is not intended to limit the scope of implementation of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this utility model, and all such improvements and modifications should be covered within the protection scope of this utility model.

Claims

1. A wheel-leg retractable obstacle-crossing robot, characterized in that, The vehicle includes a frame (4) and a wheel leg structure at its lower part, with no less than 5 wheel leg structures. The frame (4) is equipped with a control system and a motor (3), and each wheel leg structure is connected to a single motor (3). The wheel-leg structure includes a telescopic component and a wheel (1). The telescopic component includes a screw structure and an extension leg (22) that can extend and retract vertically under its control. The wheel (1) is provided at the lower part of the extension leg (22). The lead screw structure includes a screw (9) connected to the motor (3), a nut (8) meshing on the screw (9), guide rods (10) on both sides of the screw (9), and nut seats (12) that can slide on the guide rods (10) fixed on both sides of the nut (8); the extension leg (22) is fixed on the nut (8); an obstacle avoidance sensor is provided on the extension leg (22), an encoder is installed in the wheel (1), and the obstacle avoidance sensor and the encoder are both connected to the control system. 2.The wheel-leg retractable obstacle-surmounting robot according to claim 1, wherein, The upper part of the guide rod (10) is fixed with an upper mounting seat (20), which is fixed to the frame (4).

3. The wheel-legs retractable obstacle-surmounting robot according to claim 1, characterized in that, The lead screw structure is provided with a protective shell (17) on the outside, and a lower mounting seat (21) is fixed to the lower part of the guide rod (10). The lower mounting seat (21) is fixed to the protective shell (17).

4. The wheel-legs retractable obstacle-surmounting robot according to claim 1, characterized in that, The lead screw structure is a ball screw structure.

5. The wheel-legs retractable obstacle-surmounting robot according to claim 1, characterized in that, The nut (8) is fitted with disc spring assemblies (7) on both the upper and lower parts along the screw (9).

6. The wheel-legs retractable obstacle-surmounting robot according to claim 1, characterized in that, The lower sides of the extension leg (22) are respectively fixed with lower supports (13), and the two lower supports (13) are respectively fixed with the wheel axles (19) extending from both sides of the wheel (1).

7. The wheel-legs retractable obstacle-surmounting robot according to claim 6, characterized in that, A shock-absorbing device (2) is provided between the lower support (13) on one side and the wheel axle (19).

8. The wheel-legs retractable obstacle-surmounting robot according to claim 7, characterized in that, The shock absorption device (2) is a hydraulic damping shock absorber, which is connected to the lower support (13) and the wheel axle (19) respectively through ball joints (14) located at its upper and lower parts.

9. The wheel-legs retractable obstacle-surmounting robot according to claim 1, characterized in that, The wheel (1) includes a rim (16) and a hub motor disposed therein, the rim (16) being covered by a tire (18).

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