Wheel-legged robot

Abstract

The present invention relates to a wheel-legged robot comprising a body module, a wheel module connected to rotate toward or away from the body module, and a controller configured to control the movement of the robot. The wheel module is detachably connected to the body module, allowing the body module and the wheel module to operate either cooperatively or independently. The wheel module comprises a support platform connected to the body module, a plurality of angle adjustment mechanisms connected to the support platform, and a plurality of wheel assemblies, each individually connected to its respective angle adjustment mechanism, such that each wheel assembly is adjustable in angle relative to the support platform and positioned perpendicular to a surface on which the robot is provided.

Description

[0001] WHEEL-LEGGED ROBOT

[0002] TECHNICAL FIELD

[0003] Engineering related to a wheel-legged robot

[0004] BACKGROUND OF THE INVENTION

[0005] Inspection of the surface condition of various equipment, such as the surfaces of metal pipes or reactors, is necessary for operations in the manufacturing industry in order to detect and prevent surface damage, which could impact operations or the transport of various chemicals, as well as personnel safety. A common method used for inspecting the surface condition of equipment or pipes is to use a magnetic yoke flaw detector, which moves along the surface of the equipment and inspects its surface condition. A robot may be used as a carrier to help such inspection device travel along the surface, enabling a convenient, quick, and safe operation compared to inspection carried out by humans. However, since the equipment surfaces, especially pipes, often have varying shapes or arrangement patterns, such as different curvature radii or pipe arrangements (e.g., linear arrangement, pipe bends, or inclined or vertical arrangement), these shapes and arrangement patterns affect the robot's mobility. If the robot is not sufficiently developed to adapt its movement to the surface conditions, the surface inspection cannot be performed effectively and the performance of the equipment mounted on the robot may also be affected in some cases.

[0006] Exemplary patent documents disclosing movable robots suitable for different applications, such as the inspection of pipes or poles, are as follows.

[0007] CN 105730540 B discloses a moving robot and a driving method with a pole-climbing function. The moving robot includes a monitoring device, a driving control module, and a climbing mechanism. The monitoring device and the driving control module are mounted on the climbing mechanism. The climbing mechanism includes a plurality of body units and a body joint for joining adjacent body units. A body joint motor is mounted between the adjacent body units. The body unit is provided with a pair of robot arms. The end of the robot arm is provided with a walking rotary wheel and a wheel operator.

[0008] However, the robot according to the aforementioned Chinese patent still has some drawbacks, i.e., the operations of the climbing mechanism and the rotary wheel cannot be adjusted, for example, they cannot be detached from one another and the robot cannot move on a flat surface in a vertical direction. US 4,977,971 discloses a hybrid robotic vehicle provided for use in environments which are hazardous to humans, the vehicle being adapted to carry a payload for use in viewing the area or acquiring other types of sensory data. The hybrid robotic vehicle has a main body and four appendages or legs, each of which has a wheel assembly and a track assembly, and is configured to operate having three degrees-of-freedom about one vertical and two horizontal axes. The vehicle may operate in a wheeled, tracked, or legged mode, with actuators controlling each of the three joint angles on each leg, and having separate motors for driving the wheels and the tracks.

[0009] However, the robotic vehicle according to said US patent cannot move transversely relative to its body. Also, the operations of the main body / legs and the wheel assembly / track assembly cannot be separated. Therefore, its applications are limited.

[0010] KR 10-2023-0132135 discloses a transport robot which includes a body with a flat upper surface, support frames arranged on both sides of the body and inclined at a predetermined angle relative to the upper surface of the body and extending downward, legs rotatably mounted on the support frames, and wheels mounted at the ends of the legs. The legs can be folded under the body, make the body stand upright, or extend outward from the body. However, said transport robot has limitations in moving on metal pipe surface, particularly on pipes with a small radius of curvature, which may result in unstable movement. Furthermore, the body, the legs, and the wheel of the robot cannot operate separately.

[0011] Therefore, there remains a need for a robot which is developed or improved to address the limitations of the robots of the prior arts mentioned above.

[0012] SUMMARY OF THE INVENTION

[0013] An objective of the present invention is to provide a movable robot comprising components configured to solve the aforementioned problems and exhibit improved performance in various aspects. Particularly, the invention is aimed at developing a wheel-legged robot which is capable of moving in various manners, i.e., moving stably on flat and curved surfaces and moving in horizontal and vertical directions. The robot’s height can also be adjusted to expand the robot’s operational range.

[0014] In a preferred embodiment, the present invention relates to a wheel-legged robot comprising a body module, at least one wheel module connected to rotate toward or away from the body module, and at least one controller configured to control movement of the robot. The wheel module is detachably connected to the body module, allowing the body module and the wheel module to operate either cooperatively or independently. The wheel module comprises a support platform connected to the body module, a plurality of angle adjustment mechanisms connected to the support platform, and a plurality of wheel assemblies, each individually connected to its respective angle adjustment mechanism, such that each wheel assembly is adjustable in angle relative to the support platform and positioned perpendicular to a surface on which the robot is provided.

[0015] BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Fig. 1 is a perspective view showing an exemplary embodiment of the wheel-legged robot according to the present invention.

[0017] Fig. 2 is a perspective view showing an exemplary embodiment of the wheel-legged robot according to the present invention which reveals the controller and the inertial measurement unit.

[0018] Fig. 3 is a side view showing an exemplary embodiment of the wheel module of the wheel-legged robot according to the present invention which is placed on a curved surface.

[0019] Fig. 4 shows an exemplary embodiment of the wheel assembly having the lifting ring of the wheel-legged robot according to the present invention during a transition from horizontal to vertical movement.

[0020] Fig. 5 is a perspective view showing an exemplary embodiment of the wheel-legged robots according to the present invention in a connected state.

[0021] Fig. 6 is a perspective view showing the magnetic yoke flaw detector equipped with a camera.

[0022] DETAILED DESCRIPTION

[0023] Various aspects and additional advantages of the present invention will become clearer from the details to be given hereinafter, in conjunction with the accompanying drawings.

[0024] Figs. 1 to 6 show various components of the wheel-legged robot according to the present invention according to a preferred exemplary embodiment.

[0025] Technical terms related to scientific or engineering equipment or components herein are to be understood as referring to any equipment or components recognizable by a person of ordinary skill in the art.

[0026] Figs. 1 and 2 show exemplary embodiments of the wheel-legged robot according to the present invention. The robot comprises a body module (1), at least one wheel module (2) connected to rotate toward or away from the body module (1), and at least one controller (3) configured to control movement of the robot.

[0027] According to a preferred embodiment, the wheel module (2) is connected such that it can be detached from the body module (1), allowing the body module (1) and the wheel module (2) to operate either cooperatively or independently.

[0028] The wheel module (2) comprises a support platform (2.1) connected to the body module (1), a plurality of angle adjustment mechanisms (2.2) connected to the support platform (2.1), and a plurality of wheel assemblies (2.3), each individually connected to its respective angle adjustment mechanism (2.2), such that each wheel assembly (2.3) is adjustable in angle relative to the support platform (2.1) and positioned perpendicular to a surface on which the robot is provided.

[0029] According to the above embodiment, the body module (1) and the wheel module (2) which can operate cooperatively or independently allow for adjustment of the robot configuration. For example, in a state where multiple robots are connected, the body module (1) and the wheel module (2) can move together using the wheels while the height of the body module ( 1) can be increased or decreased. On the contrary, in a disconnected state, the body module ( 1) and the wheel module (2) can operate independently with the body module (1) moving in a walking-like manner and the wheel module (2) moving using the wheels.

[0030] As an example, the angle adjustment mechanism (2.2) may comprise a free revolute joint or a motorized joint, preferably a free revolute joint.

[0031] As previously mentioned and clearly seen in Fig. 3, providing the angle adjustment mechanism (2.2), i.e., the free revolute joint or motorized joint, between the support platform

[0032] (2.1) and the wheel assembly (2.3) allows the support platform (2.1) and the wheel assembly (2.3) to be angled. Each wheel assembly (2.3) is thus adjusted to be perpendicular to the surface on which it is traveling at all times. This results in smoother contact between the wheel surface and the traveling surface and effective movement. Moreover, the stability of the robot is also improved.

[0033] Referring to Figs. 2 and 3, the wheel assembly (2.3) preferably comprises a first frame

[0034] (2.3.1) connected to the angle adjustment mechanism (2.2), a first motor (2.3.2) mounted on the first frame (2.3.1), a second frame (2.3.3) connected to the first motor (2.3.2) such that the second frame (2.3.3) is rotatable in a horizontal direction, a second motor (2.3.4) mounted on the second frame (2.3.3), and a wheel (2.3.5) connected to the second motor (2.3.4) or connected to both the second frame (2.3.3) and the second motor (2.3.4).

[0035] According to the above embodiment, the second frame (2.3.3), which is connected such that it can rotate horizontally, allows the wheel (2. 3. 5) to be rotated horizontally, enabling the robot to move in multiple directions without having to turn the robot toward the direction of movement.

[0036] As an example, at least four wheel assemblies (2.3) are provided. However, the number of the wheel assembly (2.3) is not limited to four; a lesser or greater number may be provided.

[0037] According to an exemplary embodiment, the wheel assembly (2.3) is a swerve-type wheel assembly, and the wheel (2.3.5) is a rubber wheel suitable for use on general surfaces, or a magnetic wheel particularly suitable for use on metallic surfaces.

[0038] As shown in Figs. 3 and 4, the wheel assembly (2.3) may optionally comprise a lifting ring (2.3.6) provided between the wheel (2. 3. 5) and the second frame (2.3.3). The lifting ring (2.3.6) may be a circular plate mounted eccentrically with respect to the wheel (2.3.5), such that a portion of its edge extends beyond an edge of the wheel (2.3.5), while another portion remains within the edge of the wheel (2.3.5).

[0039] According to the above embodiment and as shown in Fig. 4, which simulates the scenario where the robot's wheel is transitioning its movement from a horizontal to a vertical direction by moving from the 1stposition to the 2ndposition and then to the 3rdposition, respectively. According to the figure, it can be seen that the lifting ring (2.3.6) of the wheel (2. 3. 5) (in this case, magnetic wheel) contacts the surface in the vertical direction and is pushed to rotate into a position where it extends beyond the edge of the wheel (2. 3. 5) at the position where the wheel (2.3.5) contacts the surface horizontally, and does not extend beyond the edge of the wheel (2. 3. 5) at the position where the wheel (2. 3. 5) contacts the surface vertically. Therefore, the wheel (2.3.5) is lifted such that the magnetic attraction force is reduced at the position where the wheel (2.3.5) contacts the surface vertically. As a result, the wheel (2.3.5) contacts the surface vertically in an effective manner and rotates to vertically move along the surface by reducing the drag force resulting from the attraction force of the wheel (2. 3. 5), which contacts the surface horizontally. For the movement from the vertical direction to the horizontal direction, the movement behavior of the lifting ring (2.3.6) provides a similar effect. In the robot's normal movement, the lifting ring (2.3.6) moves simultaneously with the wheel (2.3.5) such that it does not rotate into a position that would cause the wheel (2.3.5) to be lifted. According to the embodiment shown in Fig. 2, the body module (1) comprises a body (1.1) and at least two legs (1.2) mounted to the body (1.1) opposite to each other.

[0040] Each leg (1.2) comprises a main frame (1.2.1), a third motor (1.2.2) mounted to one end of the main frame (1.2.1) and connected to the body (1.1) to allow the main frame (1.2.1) to rotate toward or away from the body (1.1), a fourth motor (1.2.3) mounted to the other end of the main frame (1.2.1), and a connecting platform (1.2.4) mounted to a joint of the fourth motor (1.2.3). The connecting platform (1.2.4) is configured to connect to the support platform (2.1) of the wheel module (2) to allow the wheel module (2) to rotate toward or away from the main frame (1.2.1).

[0041] The ability of the leg (1.2) to rotate relative to the body ( 1.1) and the ability of the connecting platform ( 1.2.4) (which is connected to the support platform (2.1)) to rotate relative to the leg (1.2) enable the robot to change its direction in various ways.

[0042] The connecting platform ( 1.2.4) may be positioned such that it is movable on a ground when the body module (1) and the wheel module (2) are disconnected from one another to operate independently. That is, the connecting platform ( 1.2.4) acts like a foot which is placed on the ground to support the weight of the robot.

[0043] According to an exemplary embodiment, the body ( 1.1) may be a longitudinal axis. However, the body ( 1.1) can take any shape. The body ( 1.1) may be made of any lightweight and durable materials, such as carbon fiber.

[0044] As shown in Fig. 5, the body module ( 1) may further comprise an additional joint (1.3) mounted to the body ( 1.1) to enable connection to the body module (1) of another robot. The additional joint ( 1.3) is configured to adjust at least one of a pitch angle, a yaw angle, or a roll angle.

[0045] As an example, the additional joint (1.3) is a free revolute joint or a motorized joint.

[0046] According to the above embodiment, the body module (1) of the robot and the body module (1) of another robot which are rotatably connected to each other are advantageous in that it enables smooth overall movement.

[0047] According to a preferred embodiment of the present invention, the controller ( 3) is mounted to the body module ( 1), to at least one wheel module (2), or to both the body module (1) and each of the wheel module (2). Preferably, each controller (3) is configured to communicate with the other controller(s) such that they operate cooperatively to control joint operation of the body module (1) and each wheel module (2) when the body module (1) and the wheel module (2) are connected.

[0048] According to another embodiment of the present invention, each controller (3) is configured to control the operation of the body module (1) and the respective wheel module (2) when the body module (1) and the wheel module (2) are disconnected from one another to operate independently.

[0049] According to the above embodiment, providing the controller (3) on the body module ( 1) and the wheel module (2) allows the body module (1) and the wheel module (2) to operate cooperatively or independently, which corresponds to how the wheel module (2) can be connected such that it can be disconnected from the body module (1).

[0050] According to a further exemplary embodiment as shown in Fig. 2, the robot according to the present invention may comprise at least one inertial measurement unit (IMU) (4), each IMU (4) being mounted to the body module ( 1), to the at least one wheel module (2), or to both the body module (1) and each of the wheel module (2), and configured to monitor movement and transmit movement information to the respective or a predetermined controller ( 3). Such embodiment allows the body module (1) and each wheel module (2) to perceive the movement information either jointly or independently.

[0051] As shown in Fig. 6, the robot according to the invention may further comprise a magnetic yoke flaw detector (5) mounted to the body (1.1) of the body module (1) for detecting cracks on a surface to be inspected. Said device is used for non-destructive surface inspection of surfaces that can be magnetized. When the inspected surface has cracks, it affects the magnetic flux characteristics. The iron particles are delivered to the surface to identify the characteristics of the magnetic flux.

[0052] The magnetic yoke flaw detector (5) is generally large in size and relatively heavy. Therefore, the robot should be designed appropriately for the installation of such device to obtain accurate and safe operation.

[0053] As the robot of the present invention has a plurality of wheel assemblies (2.3) and an angle adjustment mechanism (2.2), its ability to support the weight and its stability in both stationary and moving conditions can be improved. Moreover, the movement of the body module (1) allows for various height or posture adjustments. The robot according to the present invention thus has a configuration suitable for the installation of the magnetic yoke flaw detector (5). Referring to Fig. 6, the robot according to the invention may further comprise a camera (6), which enhances the inspection efficiency. The camera (6) may be mounted to the wheel module (2) for capturing images of the surface to be inspected. In case the robot is equipped with the magnetic yoke flaw detector (5), the camera (6) may be installed on the magnetic yoke flaw detector (5) for capturing images of the surface to be inspected.

[0054] The robot according to the present invention is not limited to the embodiments described above and the drawings. The robot according to the present invention may undergo any modifications or changes. For example, it may be modified by installing additional measuring devices or sensors to suit certain applications. Any modifications or changes shall still be considered within the concept and scope of the present invention.

Claims

WHAT IS CLAIMED IS:

1. A wheel-legged robot comprising: a body module (1); at least one wheel module (2) connected to rotate toward or away from the body module (1); and at least one controller (3) configured to control movement of the robot, wherein the wheel module (2) is detachably connected to the body module (1) to allow the body module (1) and the wheel module ( 2) to operate either cooperatively or independently, and the wheel module (2) comprises: a support platform (2.1) connected to the body module (1); a plurality of angle adjustment mechanisms (2.2) connected to the support platform (2.1); and a plurality of wheel assemblies (2.3), each individually connected to its respective angle adjustment mechanism (2.2), such that each wheel assembly (2.3) is adjustable in angle relative to the support platform (2.1) and positioned perpendicular to a surface on which the robot is provided.

2. The robot according to claim 1, wherein the angle adjustment mechanism (2.2) comprises a free revolute joint or a motorized joint.

3. The robot according to claim 1, wherein the wheel assembly (2.3) comprises: a first frame (2.3.1) connected to the angle adjustment mechanism (2.2); a first motor (2.3.2) mounted on the first frame (2.3.1); a second frame (2.3.3) connected to the first motor (2.3.2) such that the second frame (2.3.3) is rotatable in a horizontal direction; a second motor (2.3.4) mounted on the second frame (2.3.3); and a wheel (2.

3. 5) connected to the second motor (2.3.4) or connected to both the second frame (2.3.3) and the second motor (2.3.4).

4. The robot according to claim 1, wherein at least four wheel assemblies (2.3) are provided.

5. The robot according to claim 1, wherein the wheel assembly (2.3) is a swerve-type wheel assembly.

6. The robot according to claim 3, wherein the wheel (2.3.5) is a rubber wheel or a magnetic wheel.

7. The robot according to claim 3, wherein the wheel assembly (2.3) further comprises a lifting ring (2.3.6) provided between the wheel (2.3.5) and the second frame (2.3.3).

8. The robot according to claim 7, wherein the lifting ring (2.3.6) is a circular plate mounted eccentrically with respect to the wheel (2.3.5), such that a portion of its edge extends beyond an edge of the wheel (2.3.5), while another portion remains within the edge of the wheel (2.3.5).

9. The robot according to claim 1, wherein the body module (1) comprises a body (1.1) and at least two legs (1.2) mounted to the body (1.1) opposite to each other, each leg (1.2) comprising: a main frame (1.2.1); a third motor (1.2.2) mounted to one end of the main frame (1.2.1) and connected to the body (1.1) to allow the main frame (1.2.1) to rotate toward or away from the body (i-i); a fourth motor (1.2.3) mounted to the other end of the main frame (1.2.1); and a connecting platform (1.2.4) mounted to a joint of the fourth motor (1.2.3), the connecting platform (1.2.4) being configured to connect to the support platform (2.1) of the wheel module (2) to allow the wheel module (2) to rotate toward or away from the main frame (1.2.1).

10. The robot according to claim 9, wherein the connecting platform ( 1.2.4) is positioned such that it is movable on a ground when the body module (1) and the wheel module (2) are disconnected from one another to operate independently.

11. The robot according to claim 9, wherein the body (1.1) is a longitudinal axis.

12. The robot according to claim 9, wherein the body (1.1) is made of carbon fiber.

13. The robot according to claim 9, wherein the body module (1) further comprises an additional joint (1.3) mounted to the body (1.1) to enable connection to the body module (1) of another robot.

14. The robot according to claim 13, wherein the additional joint (1.3) is configured to adjust at least one of a pitch angle, a yaw angle, or a roll angle.

15. The robot according to claim 13 or 14, wherein the additional joint (1.3) is a free revolute joint or a motorized joint.

16. The robot according to claim 1 , wherein the controller (3) is mounted to the body module (1), to the at least one wheel module (2), or to both the body module (1) and the wheel module (2).

17. The robot according to claim 1 or 16, wherein each controller ( 3) is configured to communicate with the other controller(s) such that they operate cooperatively to control joint operation of the body module (1) and each wheel module (2) when the body module (1) and the wheel module (2) are connected.

18. The robot according to claim 1 or 16, wherein each controller (3) is configured to control the operation of the body module (1) and the respective wheel module (2) when the body module ( 1) and the wheel module (2) are disconnected from one another to operate independently.

19. The robot according to claim 1, further comprising at least one inertial measurement unit (IMU) (4), each IMU (4) being mounted to the body module (1), to the at least one wheel module (2), or to both the body module (1) and each wheel module (2), and configured to monitor movement and transmit movement information to the respective or a predetermined controller (3).

20. The robot according to claim 9, further comprising a magnetic yoke flaw detector (5) mounted to the body (1.1) of the body module (1) for detecting cracks on a surface to be inspected.

21. The robot according to claim 1, further comprising a camera (6) mounted on the wheel module (2) for capturing images of a surface to be inspected.

22. The robot according to claim 20, further comprising a camera ( 6) mounted on the magnetic yoke flaw detector (5) for capturing images of a surface to be inspected.

Images