A universal wheel and companion robot

Abstract

The utility model provides a universal wheel and companion robot relates to robot field, wherein, universal wheel includes wheel frame and gyro wheel, the bottom of wheel frame is recessed with installation groove, and the part of gyro wheel is accommodated in installation groove and is rotatably connected wheel frame, and the other part of gyro wheel protrudes to installation groove outside, the outer surface of wheel frame includes two first surfaces, in the direction of the rotation axis of gyro wheel, two first surfaces are located the two sides of installation groove opposite, and the part of first surface near the slot of installation groove is configured as first arc surface, can guide the smooth crossing of obstacle through the position of the outer surface of wheel frame near the connecting place of wheel frame and gyro wheel by first arc surface, thereby, can effectively promote the steering and obstacle crossing performance of universal wheel, thereby providing support for the more flexible movement walking of robot.

Description

Technical Field

[0001] This application relates to the field of robotics, specifically to a universal wheel and a companion robot. Background Technology

[0002] With the development of technology, intelligent mobile robots have been widely used in home, commercial and industrial scenarios; for example, companion robots can perform corresponding behaviors according to user instructions, and because they can accompany users, they are increasingly used in home environments.

[0003] Among them, the omnidirectional wheel, as an important support and steering component in the robot, usually consists of a wheel frame and rollers. The wheel frame is connected to the robot's chassis through a positioning shaft, and the rollers are mounted on the wheel frame and can rotate freely to support the robot's multi-directional movement. However, in practical applications, when the omnidirectional wheel encounters an obstacle, the obstacle is easily stuck on the outer surface of the wheel frame near the connection between the wheel frame and the roller, causing the roller to stall or get stuck. This leads to problems such as difficulty in steering and overcoming obstacles, or even the inability to move and walk normally. Utility Model Content

[0004] The main technical problem addressed by this application is to provide a omnidirectional wheel and a companion robot that uses the omnidirectional wheel, which can improve the robot's turning and obstacle-crossing capabilities.

[0005] According to a first aspect, one embodiment provides a caster wheel, including a wheel frame, a positioning shaft, and rollers;

[0006] The bottom of the wheel frame is recessed with a mounting groove, and the positioning shaft is located at the top of the wheel frame. The wheel frame is rotatably mounted in a preset position via the positioning shaft.

[0007] A portion of the roller is housed within the mounting groove and rotatably connected to the wheel frame, while another portion of the roller protrudes outside the mounting groove, and the rotation axis of the roller is perpendicular to or at an angle to the rotation axis of the wheel frame.

[0008] The outer surface of the wheel frame includes two first surfaces; in the direction of the rotation axis of the roller, the two first surfaces are located on opposite sides of the mounting groove; the portion of the first surface near the opening of the mounting groove is constructed as a first arc-shaped surface.

[0009] In one embodiment, the outer surface of the wheel frame further includes a second surface and a third surface; in the rolling direction of the roller, the second surface and the third surface are located on opposite sides of the mounting groove; the first surface is in contact between the second surface and the third surface; wherein the first surface and / or the second surface and / or the third surface are smooth arc surface structures.

[0010] In one embodiment, the first surface, the second surface, and the third surface are all smooth arcuate structures, and adjacent first surfaces, second surfaces, and third surfaces are smoothly connected.

[0011] In one embodiment, the portions of the second surface and the third surface near the opening of the mounting groove each have a second arcuate surface.

[0012] In one embodiment, the virtual extension surface of the second arcuate surface smoothly transitions to the rolling surface of the roller.

[0013] In one embodiment, the first surface and the second surface are smooth arcuate structures; in the direction of the rotation axis of the wheel frame, the curvature of the first surface is greater than the curvature of the second surface.

[0014] In one embodiment, in the direction of the rotation axis of the wheel frame, the lowest point of the second surface is located between the lowest point of the first surface and the rotation axis of the roller; the lowest point of the third surface and the lowest point of the second surface are located on opposite sides of the rotation axis of the roller.

[0015] In one embodiment, the virtual extension surface of the first arcuate surface smoothly transitions to the rolling surface of the roller.

[0016] In one embodiment, the first surface is a smooth arcuate structure having the first arcuate surface; on a reference plane parallel to the rotation axis of the wheel frame and the rotation axis of the roller, the orthographic projection of the wheel frame and the orthographic projection of the roller together form a bowl shape.

[0017] In one embodiment, on a reference plane parallel to the rotation axis of the wheel frame and the rotation axis of the roller, the outer boundary line of the orthographic projection of the first surface and the outer boundary line of the orthographic projection of the rolling surface of the roller are circularly concentric.

[0018] In one embodiment, in the direction of the rotation axis of the wheel frame, the lowest point of the wheel frame is located between the lowest point of the roller and the rotation axis of the roller;

[0019] The height difference between the lowest point of the wheel frame and the rotation axis of the roller is the first height difference, and the height difference between the lowest point of the wheel frame and the lowest point of the roller is the second height difference. The first height difference is greater than the second height difference.

[0020] In one embodiment, the ratio of the first height difference to the second height difference is greater than 1.2.

[0021] In one embodiment, the rolling surface of the roller is an outwardly convex arc-shaped surface; on a reference plane parallel to the rotation axis of the roller and the rotation axis of the wheel frame, the outer boundary line of the orthographic projection of the rolling surface has a central lowest point and endpoints at both ends; in the direction of the rotation axis of the wheel frame, the lowest point of the wheel frame is located between the endpoints and the rotation axis of the roller, or the lowest point of the wheel frame is level with the endpoints.

[0022] In one embodiment, the lowest point of the first surface is the lowest point of the wheel frame in the direction of the rotation axis of the wheel frame.

[0023] In one embodiment, the mounting groove has a first groove, a second groove, and a third groove that are connected to each other; in the direction of the rotation axis of the roller, the second groove is located on two opposite sides of the first groove, and the third groove is located on the side of the second groove away from the first groove.

[0024] The roller includes an axle, a wheel body fitted on the axle, and two bushings, with the wheel body positioned between the two bushings; wherein a portion of the wheel body is accommodated in the first groove and another portion protrudes out of the mounting groove, the bushings are accommodated in the corresponding second groove, and the end of the axle is accommodated in the corresponding third groove.

[0025] According to a second aspect, one embodiment provides a companion robot including the omnidirectional wheels described in the first aspect.

[0026] In one embodiment, the companion robot further includes a head and a body, the head is disposed at the top of the body, drive wheels are provided on the left and right sides of the bottom end of the body, the bottom end of the body extends backward to form a tail structure, and the omnidirectional wheel is disposed at the bottom of the tail structure.

[0027] In one embodiment, the companion robot further includes a cliff sensor and / or a recharge sensor; the cliff sensor is disposed at the bottom of the tail structure and behind the omnidirectional wheel; the recharge sensor is disposed at the top of the tail structure and behind the body.

[0028] The omnidirectional wheel according to the above embodiment includes a wheel frame, a positioning shaft, and a roller. The positioning shaft is disposed at the top of the wheel frame, and a mounting groove is recessed at the bottom of the wheel frame. A portion of the roller is accommodated in the mounting groove and rotatably connected to the wheel frame, while another portion of the roller protrudes outside the mounting groove. The outer surface of the wheel frame includes two first surfaces. In the direction of the roller's rotation axis, the two first surfaces are located on opposite sides of the mounting groove. The portion of the first surface near the opening of the mounting groove is constructed as a first arc-shaped surface. The first arc-shaped surface can guide obstacles smoothly across the outer surface of the wheel frame near the connection point between the wheel frame and the roller. Therefore, the steering and obstacle-crossing performance of the omnidirectional wheel can be effectively improved, thereby providing support for the robot to move and walk more flexibly. Attached Figure Description

[0029] Figure 1 This is a schematic cross-sectional view of the omnidirectional wheel according to one embodiment (I).

[0030] Figure 2 A three-dimensional structural schematic diagram (a) of a universal wheel according to one embodiment.

[0031] Figure 3 A three-dimensional structural schematic diagram (II) of a universal wheel according to one embodiment.

[0032] Figure 4 This is an exploded view of the structure of a universal wheel according to one embodiment.

[0033] Figure 5 This is a schematic cross-sectional view of the omnidirectional wheel in one embodiment (II).

[0034] Figure 6 This is a side view of a swivel wheel with the positioning axis omitted, according to one embodiment.

[0035] Figure 7 This is a front view schematic diagram of a universal wheel with the positioning axis omitted, according to one embodiment.

[0036] Figure 8 This is a three-dimensional structural diagram of a companion robot according to one embodiment.

[0037] Figure 9 for Figure 8 A partial structural diagram of the companion robot.

[0038] In the picture:

[0039] 10. Wheel frame; 11. Mounting slot; 111. First slot; 112. Second slot; 113. Third slot; 114. Protruding structure; P1a and P1b. Virtual extension surfaces; P11. First surface; P12. Second surface; P13. Third surface; L1. First axis; 20. Roller; 21. Wheel body; 22. Wheel axle; 23. Bushing; P21. Rolling surface; L2. Second axis; L2. Second axis; 30. Positioning shaft; 40. Positioning sleeve;

[0040] 100. Caster wheel; 200. Head; 300. Body; 400. Drive wheel; 500. Tail structure; 600. Cliff sensor; 700. Recharge sensor. Detailed Implementation

[0041] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments. Similar elements in different embodiments are referred to by related similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of the present application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to the present application are not shown or described in the specification. This is to avoid obscuring the core parts of the present application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0042] In the description herein, 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,” “counterclockwise,” “axial,” “radial,” and “circumferential” 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 application 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 limitations on this application.

[0043] 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 technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0044] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection, an abutment, or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0045] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0046] The embodiments described in the detailed implementation can be combined in any suitable manner without contradiction. For example, different implementation methods can be formed by combining different embodiments. In order to avoid unnecessary repetition, the various possible combinations of the embodiments will not be described separately.

[0047] Please see Figures 1 to 7 This application provides a universal wheel that can be installed on mobile walking devices (such as service robots, cleaning robots, companion robots, etc.) to support the devices in achieving functions such as walking, turning, and obstacle crossing. The universal wheel includes a wheel frame 10, a roller 20, a positioning shaft 30, and other components as needed, which are described in detail below.

[0048] Please see Figures 1 to 5 The positioning shaft 30 is disposed on the top of the wheel frame 10, and the wheel frame 10 is rotatably mounted in a preset position (e.g., the bottom of the mobile walking device) via the positioning shaft 30. Exemplarily, one end of the positioning shaft 30 is fixedly connected to the wheel frame 10, and the mobile walking device is fixedly connected to a positioning sleeve 40. The positioning shaft 30 is rotatably inserted into the positioning sleeve 40, thereby establishing a relative rotational connection between the wheel frame 10 and the mobile walking device using the positioning shaft 30 and the positioning sleeve 40.

[0049] Please see Figures 1 to 5The bottom of the wheel frame 10 is recessed with a mounting groove 11. A portion of the roller 20 is housed in the mounting groove 11 and rotatably connected to the wheel frame 10, while the other portion of the roller 20 protrudes out through the opening of the mounting groove 11. Exemplarily, the roller 20 includes a wheel body 21, a wheel axle 22, and two bushings 23. The wheel body 21 and bushings 23 are both fitted onto the wheel axle 22, with the wheel body 21 positioned between the two bushings 23. The outer diameter of the wheel body 21 is set to be larger than the depth of the mounting groove 11. Both ends of the wheel axle 22 are rotatably connected to the wheel frame 10 within the mounting groove 11, such that a portion of the wheel body 21 is within the mounting groove 11, and the other portion protrudes out of the mounting groove 11. A relative rotational connection is established between the wheel body 21 and the wheel frame 10 using the wheel axle 22.

[0050] The rotation axis of the wheel frame 10 is perpendicular to or at an angle to the rotation axis of the roller 20, so that when the omnidirectional wheel is installed and applied to a mobile walking device, the omnidirectional wheel as a whole can rotate in multiple directions based on the different rotation axes (or different rotation dimensions) of the wheel frame 10 and the roller 20.

[0051] Specifically, please refer to Figure 2 , Figure 3 , Figure 6 and Figure 7 For ease of distinction and description, the rotation axis of the wheel frame 10 is defined as the first axis L1, and the rotation axis of the roller 20 is defined as the second axis L2. The first axis L1 and the second axis L2 can be perpendicular to each other; for example, they can be perpendicular despite being in opposite planes or perpendicular despite being coplanar. It should be understood that while the first axis L1 and the second axis L2 can be ideally absolutely perpendicular, there may be some deviation due to processing or installation errors. Therefore, the first axis L1 and the second axis L2 can also be approximately perpendicular, close to 90 degrees. The first axis L1 and the second axis L2 can form an angle. For example, when the caster wheel is installed on a mobile walking device, the direction of the first axis L1 is approximately vertical, and the direction of the second axis L2 is approximately horizontal.

[0052] For a clearer and more detailed explanation of the omnidirectional wheels provided in the embodiments of this application, please refer to [link / reference needed]. Figure 2 , Figure 3 , Figure 6 and Figure 7In this paper, a first surface P11, a second surface P12, and a third surface P13 are defined for the wheel frame 10. The first surface P11 is the outer surface of the wheel frame 10 located on opposite sides of the mounting groove 11 in the direction of the second axis L2. The second surface P12 and the third surface P13 are the outer surface of the wheel frame 10 located on opposite sides of the mounting groove 11 in the rolling direction of the roller 20. The first surface P11 is connected between the second surface P12 and the third surface P13 to jointly form the outer surface of the wheel frame 10 or the outer surface of the wheel frame 10 distributed around the mounting groove 11 and its groove opening. Meanwhile, a rolling surface P21 is defined for the roller 20. The rolling surface P21 refers to the surface of the roller 20 that protrudes out of the mounting groove 11 from the circumferential surface (e.g., the circumferential surface of the wheel body 21) enclosed by the second axis L2. That is, when the roller 20 is assembled with the wheel frame 10, a part of the circumferential surface of the roller 20 will be inside the mounting groove 11, while the other part of the circumferential surface that protrudes out of the mounting groove 11 is the rolling surface P12.

[0053] It should be noted that there is not necessarily a visible dividing line between the first surface P11, the second surface P12, and the third surface P13; that is, the first surface P11, the second surface P12, and the third surface P13 may simply represent the surfaces of the wheel frame 10 in different orientations, and the difference between the surfaces may simply be the difference in spatial orientation.

[0054] In some embodiments, please refer to Figures 2 to 5 and Figure 7 The portion of the first surface P11 near the opening of the mounting groove 11 is constructed as an arc-shaped surface. For ease of distinction and description, this arc-shaped surface is defined as the first arc-shaped surface. Since the first surface P11 is located on opposite sides of the mounting groove 11 in the direction of the second axis L2, the first arc-shaped surface is closer to the connection between the wheel frame 10 and the roller 20 compared to other parts of the first surface P11.

[0055] Compared to related technologies, the outer surface of the wheel frame 10 near the rotating connection adopts a planar structure. Based on the first arc surface, a smooth transition arc surface structure can be formed on the outer surface of the wheel frame 10 near the rotating connection. When the omnidirectional wheel encounters an obstacle, the first arc surface can guide the omnidirectional wheel's travel path or the obstacle, making it less likely for the obstacle to stay on the outer surface of the wheel frame 10 near the connection. This reduces or even avoids the risk of the obstacle getting stuck on the outer surface of the wheel frame 10 near the connection between the wheel frame 10 and the roller 20, giving the omnidirectional wheel more flexible rotation and obstacle-crossing ability.

[0056] In some embodiments, please refer to Figure 7The first arc-shaped surface and the rolling surface P21 of the roller 20 are set to transition smoothly; specifically, the virtual extension surface P1a of the first arc-shaped surface can smoothly transition to the rolling surface P21 of the roller 20; where "smooth transition" can be understood as the virtual extension surface P1a and the rolling surface P21 at least partially overlapping.

[0057] Thus, based on the smooth transition relationship between the first arc-shaped surface and the rolling surface P21, the part of the first surface P11 near the roller 20 and the rolling surface P21 of the roller 20 can jointly form a relatively smooth and outwardly convex curved surface shape.

[0058] On the one hand, when the swivel wheel encounters an obstacle, such as when the first arc surface contacts the obstacle before the roller, the first arc surface can be used to guide the obstacle smoothly across the connection between the wheel frame 10 and the roller 20, so as to guide the obstacle to the rolling surface P21, thereby effectively preventing the obstacle from getting stuck in the connection between the wheel frame 10 and the roller 20.

[0059] On the other hand, it helps to reduce or narrow the height difference or height gap between the first surface P11 and the rolling surface P21, thereby providing support for further preventing obstacles from getting stuck on the outer surface of the wheel frame 10 near the connection between the wheel frame 10 and the roller 20.

[0060] In other embodiments, the virtual extension surface P1a of the first arc-shaped surface can also smoothly transition to the axial end face of the roller 20 in the direction of the second axis L2. Based on the smooth transition structure formed by the first arc-shaped surface near the slot of the mounting groove 11 or near the connection, the risk of obstacles getting stuck on the outer surface of the wheel frame 10 near the connection between the wheel frame 10 and the roller 20 can also be reduced or even avoided.

[0061] In some embodiments, please refer to Figure 5 and Figure 7 The first surface P11 adopts a smooth arc surface structure with a first arc surface; on a reference plane parallel to the first axis L1 and the second axis L2, the orthographic projection of the wheel frame 10 and the orthographic projection of the roller 20 together form a bowl shape.

[0062] For example, please refer to Figure 7 On a reference plane parallel to the first axis L1 and the second axis L2, the outer boundary line of the orthographic projection of the first surface P11 and the outer boundary line of the orthographic projection of the rolling surface P21 can be circular or approximately circular.

[0063] Therefore, the bowl-shaped or smooth arc-shaped surface formed by the first surface P11 of the wheel frame 10 and the rolling surface P21 of the roller 20 ensures that there are no large structural gaps or protruding edges between the first surface P11, the rolling surface P21, and the two, thus effectively preventing the wheel frame 10 from getting stuck with obstacles. At the same time, when the smooth arc-shaped first surface P11 contacts the obstacle before the roller 20, it can guide the obstacle well, thereby effectively reducing the probability of the obstacle getting stuck on the outer surface of the wheel frame 10 near the connection between the wheel frame 10 and the roller 20, providing support for improving the flexible steering and obstacle-crossing performance of the omnidirectional wheel.

[0064] In some embodiments, please refer to Figures 2 to 4 and Figure 6 The portions of the second surface P12 and the second surface P13 near the opening of the mounting groove 11 can also be constructed as arc-shaped surfaces. For ease of distinction and description, this arc-shaped surface is defined as the second arc-shaped surface. The first arc-shaped surface and the second arc-shaped surface can be smoothly connected.

[0065] By using arc-shaped surfaces for the portions of the first surface P11, the second surface P12, and the third surface P13 near the opening of the mounting groove 11, it is equivalent to constructing the outer surface of the wheel frame 10 around the opening of the mounting groove 11 into a relatively smooth arc-shaped curved surface structure. This helps to further reduce or avoid the risk of obstacles getting stuck on the outer surface of the wheel frame 10 near the connection between the wheel frame 10 and the roller 20.

[0066] In some embodiments, please refer to Figure 6 and Figure 7 The virtual transition surface P1a of the first arc-shaped surface and the virtual extension surface P1b of the second arc-shaped surface both smoothly transition to the rolling surface P21 of the roller 20. That is, the first arc-shaped surface is equivalent to smoothly transitioning from the axial side of the roller 20 to the rolling surface P21 of the roller 20 through the virtual extension surface P1a (see [link]). Figure 7 The second arcuate surface is equivalent to a smooth transition from the outer periphery of the roller 20 to the rolling surface P21 of the roller 20 via a virtual extension surface P1b (see [link]). Figure 6 )

[0067] This design ensures that the surface morphology of the wheel frame 10 around the groove of the mounting slot 11 matches the morphology of the rolling surface P21, resulting in a relatively smooth and outwardly convex curved surface on the bottom surface of the omnidirectional wheel. On one hand, by smoothly transitioning the outer surface of the wheel frame 10 near the roller 20, the overall bottom surface of the omnidirectional wheel is constructed into a relatively smooth curved surface. This helps reduce the structural gap between the wheel frame 10 and the roller 20 (e.g., the height difference between them along the first axis L1 or in the vertical direction), effectively reducing the risk of obstacles getting stuck on the outer surface of the wheel frame 10 near the connection between the wheel frame 10 and the roller 20, thus ensuring the flexibility of the omnidirectional wheel's rotation and steering.

[0068] On the other hand, when the omnidirectional wheel encounters an obstacle during its movement, the smooth transition between the arc surface of the wheel frame 10 and the rolling surface P21 of the roller 20 can guide the obstacle in all directions, enabling the obstacle to pass over the wheel frame 10 more smoothly and come into contact with the rolling surface P21 of the roller 20, thereby enhancing the obstacle-crossing ability of the omnidirectional wheel.

[0069] In other embodiments, the virtual extension surface P1a of the first arc-shaped surface smoothly transitions to the axial end face of the roller 20 in the direction of the second axis L2, and the virtual extension surface P1b of the second arc-shaped surface can smoothly transition to the rolling surface P21 of the roller 20; thus, based on the arc-shaped surface of the outer surface of the wheel frame 10 near the groove of the mounting groove 11, the probability of obstacles getting stuck on the outer surface of the wheel frame 10 near the connection between the wheel frame 10 and the roller 20 can also be reduced, thereby meeting different needs.

[0070] In other embodiments, the arcuate surface of the third surface P13 may be omitted; specifically, please refer to... Figure 6 In the direction of the first axis L1, the lowest point of each of the first surface P11, the second surface P12 and the third surface P13 is located near the opening of the mounting groove 11; wherein, in the direction of the first axis L1, the lowest point a of the first surface P11 is the lowest point of the outer surface of the wheel frame 10, and the lowest point b of the second surface P12 is located between the lowest point c of the third surface P13 and the lowest point a of the first surface P11.

[0071] When installing omnidirectional wheels, since the lowest point c of the third surface P13 is at a relatively high height, the probability of the third surface P13 contacting obstacles is low. In this case, omitting the curved surface of the third surface P13 and using a non-curved surface or other suitable geometry may not affect the steering and obstacle crossing of the omnidirectional wheel.

[0072] It should be noted that the "virtual extended surface" mentioned in this article refers to a surface formed by extending the curved surface along its extension direction (for example, the virtual extended surface has the same curvature as the corresponding curved surface or the curvature remains continuous). This virtual extended surface is not a real surface. Figure 6 and Figure 7 The virtual extension surfaces P1b and P1a are roughly indicated by bold dashed lines.

[0073] It is understandable that the introduction of the "virtual extension surface" description is only to more clearly describe the structural or morphological relationship between the outer surface of the wheel frame 10 and the outer surface of the roller 20. Since the virtual extension surface is not a real surface, the outer surface of the wheel frame 10 and the outer surface of the roller 20 are not in contact, and there is a certain structural gap between them.

[0074] In some embodiments, please refer to Figure 2 , Figure 3 , Figure 6 and Figure 7 The first surface P11 is a smooth arc surface structure with a first arc surface, the second surface P12 and the second surface P13 are smooth arc surface structures with a second arc surface, and the adjacent first surface P11, second surface P12 and third surface P13 are smoothly connected.

[0075] Therefore, based on the fact that each surface of the wheel frame 10 adopts a smooth arc surface structure and the surfaces are smoothly connected, the bottom outer surface of the wheel frame 10 (i.e. the outer surface distributed around the mounting groove 11) can be constructed into a relatively continuous, complete and smooth natural curved surface shape, so that the bottom outer surface of the wheel frame 10 will not have protruding edges. This not only prevents obstacles from getting stuck with the wheel frame 10, but also helps to improve the overall aesthetic appearance of the wheel frame 10 and the omnidirectional wheel.

[0076] Of course, the first surface P11, the second surface P12, and the third surface P13 can also adopt other suitable surface structures, such as a smooth arc surface structure in which the second surface P12 or the third surface P13 smoothly connects with the first surface P11. However, the part of the second surface P12 or the third surface P13 near the groove opening of the mounting groove 11 can be constructed as a planar structure perpendicular to the direction of the first axis L1. All of these are possible as long as the first surface P11 has a first arc surface.

[0077] In some embodiments, please refer to Figure 6 and Figure 7 The first surface P11 and the second surface P12 are both smooth arc surface structures with arc-shaped surfaces; wherein, in the direction of the first axis L1, the curvature of the first surface P11 is set to be greater than the curvature of the second surface P12.

[0078] For example, please refer to Figure 6 The positioning shaft 30 is located at the top center of the wheel frame 10, and the roller 20 (or mounting groove 11) is eccentrically positioned relative to the top center of the wheel frame 10, so that the first axis L1 and the second axis L2 are perpendicular to each other. On the reference plane perpendicular to the second axis L2, the first axis L1 is located between the second axis L2 and the outer boundary line of the orthographic projection of the second surface P12, and the outer boundary line of the orthographic projection of the second surface P12 extends from the top of the wheel frame 10 to a position close to the rolling surface P21 of the roller 20.

[0079] Thus, based on the curvature difference between the first surface P11 and the second surface P12, the second surface P12 can be constructed as a smooth arc surface structure that extends from the top of the wheel frame 10 towards the bottom. The second surface P12 can be used as a guide surface for the omnidirectional wheel. When the omnidirectional wheel encounters an obstacle in front of it, the second surface P12 can be used to gently guide the obstacle to the roller 20, thereby improving the obstacle-crossing ability of the omnidirectional wheel.

[0080] In some embodiments, please refer to Figure 6 and Figure 7 In the direction of the first axis L1, the lowest point b of the second surface P12 (e.g., the lowest point of the second arc surface) is located between the lowest point a of the first surface P11 (e.g., the lowest point of the first arc surface) and the second axis L2. The lowest point b of the second surface P12 and the lowest point c of the third surface P13 are located on both sides of the second axis L2. The lowest point of the outer surface of the wheel frame 10 near the opening of the mounting groove 11 is located on the first surface P11, and the highest point is located on the third surface P13.

[0081] Please see Figure 6 and Figure 7 The lowest point of the roller 20 is located on the rolling surface P21; in the direction of the first axis L1, the lowest point of the outer surface of the wheel frame 10 is located between the lowest point of the roller 20 and the second axis L2; ​​wherein, the height difference between the lowest point of the wheel frame 10 and the second axis L2 is the first height difference H1, and the height difference between the lowest point of the wheel frame 10 and the lowest point of the roller 20 is the second height difference H2, and the first height difference H1 is greater than the second height difference H2; for example, the ratio of the first height difference H1 to the second height difference H2 can be greater than 1.2.

[0082] Firstly, by setting the height of the lowest point of the wheel frame 10 to be close to the height of the lowest point of the roller 20, the omnidirectional wheel can smoothly cross obstacles, effectively improving the obstacle-crossing performance of the omnidirectional wheel.

[0083] Secondly, since the connection between the wheel frame 10 and the roller 20 is located inside the first surface P11, taking the lowest point of the part of the first surface P11 near the opening of the mounting groove 11 as the lowest point of the overall outer surface of the wheel frame 10 can effectively reduce the height difference between the outer surface of the wheel frame 10 and the roller 20, thereby effectively preventing obstacles from getting stuck on the outer surface of the wheel frame 10 near the connection between the wheel frame 10 and the roller 20.

[0084] Third, setting the lowest point b of the second surface P12 between the second axis L2 and the lowest point of the wheel frame 10 is beneficial to constructing the second surface P12 as the guide surface of the omnidirectional wheel.

[0085] In some embodiments, please refer to Figures 2 to 7 The rolling surface P21 is an outwardly convex arc-shaped surface. Please refer to [link / reference]. Figure 7 On a reference plane parallel to the first axis L1 and the second axis L2, the outer boundary line of the orthographic projection of the rolling surface P21 has a central lowest point d and two endpoints e at both ends; wherein, the lowest point d is the lowest point of the roller 20, and in the direction of the first axis L1, the lowest point of the wheel frame 10 is located between the endpoint e and the second axis L2, or the lowest point of the wheel frame 10 is level with or approximately level with the endpoint e.

[0086] On the one hand, by constructing the rolling surface P21 as an outwardly convex arc-shaped rotating surface, it is beneficial to reduce the contact area between the roller 20 and the ground or obstacles, and avoid unnecessary friction or resistance between the roller 20 and the ground during rotation, so that the caster can move flexibly and smoothly.

[0087] On the other hand, by limiting the lowest point of the wheel frame 10 to the position near the end point e of the rolling surface P21, the rotation of the roller 20 will not be affected by the position of the wheel frame 10 being too low, nor will the wheel frame 10 be too high, which would easily cause obstacles to get stuck on the outer surface of the wheel frame 10 near the connection between the wheel frame 10 and the roller 20.

[0088] It should be noted that, Figure 6 and Figure 7 The solid dots represent the approximate positions of the lowest points corresponding to each surface of the wheel frame 10 on the wheel frame 10, as well as the lowest point and endpoint of the outer boundary line of the orthographic projection of the rolling surface P21.

[0089] Please see Figure 4 and Figure 5 As mentioned above, in some embodiments, the roller 20 includes a wheel body 21, a wheel axle 22, and two bushings 23. Accordingly, please refer to Figure 4The mounting groove 11 has a first groove 111, a second groove 112, and a third groove 113 that are connected to each other. In the direction of the second axis L2, the second groove 112 is located on both sides opposite to the first groove 111, and the third groove 113 is located on the side of the second groove 112 away from the first groove 111. Part of the wheel body 21 is accommodated in the first groove 111, and another part protrudes out of the mounting groove 11. The bushing 23 is accommodated in the corresponding second groove 112, and the end of the wheel axle 22 is accommodated in the corresponding third groove 113.

[0090] By setting the groove shape of the mounting groove 11 to match the contour shape of the roller 20, it not only facilitates the convenient and quick assembly and disassembly of the roller 20 and the wheel frame 10, but also allows most of the structure of the roller 20 to be housed inside the mounting groove 11 or the wheel frame 10, reducing the structural gap between the roller 20 and the wheel frame 10 and providing support to prevent obstacles from getting stuck at the connection between the roller 20 and the wheel frame 10.

[0091] In some embodiments, please refer to Figure 4 The mounting groove 11 is also provided with a limiting structure, which is located between the adjacent second groove 112 and the third groove 113. This limiting structure is used to restrict the end of the wheel axle 22 into the third groove 113, thereby ensuring the stability of the connection between the roller 20 and the wheel frame 10, and that the roller 20 can rotate smoothly relative to the wheel frame 10.

[0092] For example, the limiting structure may include two protruding structures 114 that are spaced apart from each other and protrude from the groove wall of the mounting groove 11. When assembling the roller 20 and the wheel frame 10, the roller 20 can be pressed into the mounting groove 11 from the opening of the mounting groove 11, so that the end of the wheel axle 22 passes between the two protruding structures 114 and enters the third groove 113 by pressing the protruding structures 114. Thus, by using the limiting of the wheel axle 22 formed by the protruding structures 114, the roller 20 is limited in the mounting groove 11, and the roller 20 can rotate relative to the wheel frame 10.

[0093] Of course, the roller 20 can also be confined within the mounting groove 11 using other suitable structural forms, which will not be elaborated here.

[0094] Please see Figure 8 and Figure 9 This application also provides a companion robot, wherein, Figure 8 An animal-shaped companion robot is shown. This companion robot can establish an interactive relationship with users through functions such as voice interaction, visual feedback, and walking, thereby providing users with services such as safety monitoring, daily care, and emotional companionship.

[0095] Specifically, please refer to Figure 8The companion robot includes a head 200, a body 300, and omnidirectional wheels as described in any of the aforementioned embodiments. For ease of distinction and description, the omnidirectional wheels are defined as omnidirectional wheels 100. The head 200 is located at the top of the body 300 and may include components such as a camera for capturing images and a display screen for displaying images to the user. Drive wheels 400 are located on the left and right sides of the bottom of the body 300, and the bottom of the body 300 extends backward to form a tail structure 500. The omnidirectional wheels 100 are located at the bottom of the tail structure 500, thus forming a roughly triangular arrangement with the two drive wheels 400 at the bottom of the companion robot. The two drive wheels 400 provide power for the robot's movement, while the omnidirectional wheels 100 provide support for the robot's turning and obstacle crossing. In other words, based on the omnidirectional wheels 100, the robot can have more flexible turning and obstacle crossing capabilities.

[0096] In some embodiments, please refer to Figure 8 and Figure 9 The robot also includes a cliff sensor 600 and / or a recharge sensor 700. The cliff sensor 600 may include an infrared rangefinder, a laser rangefinder, etc., and is located at the bottom of the tail structure 500 and behind the omnidirectional wheel 100. By detecting obstacles (such as cliffs, pits, steps, etc.) using the cliff sensor 600, the robot can provide signal support for adjusting its movement path in real time, triggering stops or turns, etc. The recharge sensor 700 may include an infrared sensor, which may be located at the top of the tail structure 500 and behind the body 300. The recharge sensor can provide signal support for the robot to accurately identify the location of the power source, so as to guide the robot towards the power source when the battery is low, thereby completing the charging.

[0097] Of course, companion robots can also include other functional sensors to enable them to move and walk autonomously; for example, an obstacle avoidance sensor can be installed on the front side of the body 300 to detect obstacles in front of the companion robot's path; and so on, which will not be elaborated here.

[0098] The above-described specific examples are for illustrative purposes only and are not intended to limit the scope of this invention. Those skilled in the art to which this invention pertains can make various simple deductions, modifications, or substitutions based on the concept of this invention.

Claims

1. A universal wheel, characterized in that, Includes wheel frame, positioning shaft and rollers; The bottom of the wheel frame is recessed with a mounting groove, and the positioning shaft is located at the top of the wheel frame. The wheel frame is rotatably mounted in a preset position via the positioning shaft. A portion of the roller is housed within the mounting groove and rotatably connected to the wheel frame, while another portion of the roller protrudes outside the mounting groove, and the rotation axis of the roller is perpendicular to or at an angle to the rotation axis of the wheel frame. The outer surface of the wheel frame includes two first surfaces; in the direction of the rotation axis of the roller, the two first surfaces are located on opposite sides of the mounting groove; the portion of the first surface near the opening of the mounting groove is constructed as a first arc-shaped surface.

2. The universal wheel as described in claim 1, characterized in that, The outer surface of the wheel frame also includes a second surface and a third surface; in the rolling direction of the roller, the second surface and the third surface are located on opposite sides of the mounting groove; the first surface is in contact between the second surface and the third surface; wherein the first surface and / or the second surface and / or the third surface are smooth arc surface structures.

3. The universal wheel as described in claim 2, characterized in that, The first surface, the second surface, and the third surface are all smooth arc surface structures, and adjacent first surfaces, second surfaces, and third surfaces are smoothly connected.

4. The universal wheel as described in claim 2, characterized in that, The portions of the second surface and the third surface near the opening of the mounting groove each have a second arc-shaped surface.

5. The universal wheel as described in claim 4, characterized in that, The virtual extension surface of the second arc-shaped surface smoothly transitions to the rolling surface of the roller.

6. The universal wheel as described in claim 2, characterized in that, The first surface and the second surface are smooth arc surface structures; in the direction of the rotation axis of the wheel frame, the curvature of the first surface is greater than the curvature of the second surface.

7. The universal wheel as described in claim 2, characterized in that, In the direction of the rotation axis of the wheel frame, the lowest point of the second surface is located between the lowest point of the first surface and the rotation axis of the roller; the lowest point of the third surface and the lowest point of the second surface are located on opposite sides of the rotation axis of the roller.

8. The universal wheel as described in claim 1, characterized in that, The virtual extension surface of the first arc-shaped surface smoothly transitions to the rolling surface of the roller.

9. The universal wheel as described in claim 1, characterized in that, The first surface is a smooth arc surface structure with the first arc surface; on a reference plane parallel to the rotation axis of the wheel frame and the rotation axis of the roller, the orthographic projection of the wheel frame and the orthographic projection of the roller together form a bowl shape.

10. The universal wheel as described in claim 1, characterized in that, On a reference plane parallel to the rotation axis of the wheel frame and the rotation axis of the roller, the outer boundary line of the orthographic projection of the first surface and the outer boundary line of the orthographic projection of the rolling surface of the roller are circular arcs.

11. The caster wheel as described in any one of claims 1-10, characterized in that, In the direction of the rotation axis of the wheel frame, the lowest point of the wheel frame is located between the lowest point of the roller and the rotation axis of the roller; The height difference between the lowest point of the wheel frame and the rotation axis of the roller is the first height difference, and the height difference between the lowest point of the wheel frame and the lowest point of the roller is the second height difference. The first height difference is greater than the second height difference.

12. The caster wheel as described in claim 11, characterized in that, The ratio of the first height difference to the second height difference is greater than 1.

2.

13. The caster wheel as described in claim 11, characterized in that, The rolling surface of the roller is an outwardly convex arc-shaped surface; on a reference plane parallel to the rotation axis of the roller and the rotation axis of the wheel frame, the outer boundary line of the orthographic projection of the rolling surface has a central lowest point and endpoints at both ends; in the direction of the rotation axis of the wheel frame, the lowest point of the wheel frame is located between the endpoints and the rotation axis of the roller, or the lowest point of the wheel frame is level with the endpoints.

14. The caster wheel as described in any one of claims 1-10, characterized in that, In the direction of the rotation axis of the wheel frame, the lowest point of the first surface is the lowest point of the wheel frame.

15. The caster wheel as described in any one of claims 1-10, characterized in that, The mounting groove has a first groove, a second groove, and a third groove that are connected to each other; in the direction of the rotation axis of the roller, the second groove is located on both sides opposite to the first groove, and the third groove is located on the side of the second groove away from the first groove. The roller includes an axle, a wheel body fitted on the axle, and two bushings, with the wheel body positioned between the two bushings; wherein a portion of the wheel body is accommodated in the first groove and another portion protrudes out of the mounting groove, the bushings are accommodated in the corresponding second groove, and the end of the axle is accommodated in the corresponding third groove.

16. A companion robot, characterized in that, Includes the caster wheel as described in any one of claims 1-15.

17. The companion robot as described in claim 16, characterized in that, The companion robot also includes a head and a body. The head is located at the top of the body. Drive wheels are provided on the left and right sides of the bottom of the body. The bottom of the body extends backward to form a tail structure. The universal wheels are located at the bottom of the tail structure.

18. The companion robot as described in claim 17, characterized in that, The companion robot also includes a cliff sensor and / or a recharge sensor; the cliff sensor is located at the bottom of the tail structure and behind the omnidirectional wheel; the recharge sensor is located at the top of the tail structure and behind the body.

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