Control method of wheel-foot robot

Abstract

The invention discloses a control method of a wheel-foot robot. The control method comprises the following steps: S1, switching the wheel-foot robot from a first posture to a second posture; s2, acquiring attitude information of the frame body in real time; and S3, according to the frame body posture information, the second rotating part is controlled to rotate around the second rotating shaft, so that the dynamic balance of the wheel-foot robot is kept. According to the wheel-foot robot, when the wheel-foot robot is in the second posture, the second rotating shaft is located at the angle parallel to the Z-axis direction or approximately parallel to the Z-axis direction, so that when the second rotating piece rotates around the second rotating shaft, the first wheel foot can be driven to generate displacement in the X-axis direction, and deflection of the frame body in the X-axis direction is balanced; and the whole wheel-foot robot keeps dynamic balance in the X-axis direction when advancing in the Y-axis direction.

Description

Technical Field

[0001] The present invention relates to the technical field of robots, and in particular to a control method for a wheeled robot. Background Art

[0002] Wheeled-legged robots combine the locomotion capabilities of both wheels and legs. Their design blends the speed advantage of wheeled robots with the obstacle-crossing capabilities of legged robots, representing a significant innovation in the field of mobile robotics. Compared to traditional robots with a single mode of movement, wheeled-legged robots achieve multimodal locomotion through their unique structural design, significantly improving their ability to adapt to complex environments and opening up new possibilities for expanding robotic applications.

[0003] In order to adapt to various working conditions, existing wheeled robots have the function of standing and walking on their front legs or hind legs. However, when the wheeled robots only stand and move on their front legs or hind legs, their posture is not stable due to the loss of partial support. Summary of the Invention

[0004] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is to propose a control method for a wheeled-legged robot, which is used to solve the problems of unstable posture of the wheeled-legged robot when standing and walking in the prior art.

[0005] The technical solution adopted by the present invention to solve its technical problem is a control method for a wheeled robot, wherein the wheeled robot includes a frame, at least two first wheel groups and at least two second wheel groups, wherein the first wheel groups and the second wheel groups are both arranged on the frame; the first wheel group includes a first rotating member rotatable around a first rotating axis relative to the frame, a second rotating member rotatable around a second rotating axis relative to the first rotating member, and a first wheel foot rotatably connected to the second rotating member; the second wheel group includes a third rotating member rotatable around a third rotating axis relative to the frame, and a second wheel foot rotatably connected to the third rotating member; The wheeled robot has a first posture and a second posture. When the wheeled robot is in the first posture, the first wheeled foot and the second wheeled foot jointly support the frame, the first rotation axis is parallel to the Z-axis direction, the second rotation axis is parallel to the Y-axis direction, and the third rotation axis is parallel to the Y-axis direction; when the wheeled robot is in the second posture, the second wheeled foot alone supports the frame and can move along the Y-axis direction; The control method comprises the steps of: S1. Switching the wheeled robot from the first posture to the second posture; wherein, during the process of switching the wheeled robot from the first posture to the second posture, the frame rotates around the third rotation axis, the second rotating member rotates around the second rotation axis, and the first rotating member rotates around the first rotation axis; S2. Acquire the posture information of the frame in real time; S3. Control the second rotating member to rotate around the second rotating axis according to the frame posture information to maintain the dynamic balance of the wheeled robot.

[0006] The present invention has at least the following beneficial effects: When the wheeled robot is in the second posture, the second rotating shaft is at an angle parallel to or approximately parallel to the Z-axis direction, so that when the second rotating member rotates around the second rotating shaft, it can drive the first wheeled foot to produce a displacement along the X-axis direction, so as to balance the deflection of the frame in the X-axis direction, so that the entire wheeled robot maintains dynamic balance in the X-axis direction when moving along the Y-axis direction.

[0007] Furthermore, each of the second wheel feet has a contact position with the working surface, and a plane passing through the centers of at least two of the contact positions and perpendicular to the X-axis direction is defined as a support plane; The posture information of the frame includes the position, movement direction, movement speed and yaw angle of the frame relative to the support plane.

[0008] Further, in step S3, when the frame moves to one side of the support plane, the second wheel foot moves to the other side of the support plane.

[0009] Further, in step S3, the movement direction of the second wheel foot relative to the support plane is opposite to the movement direction of the frame relative to the support plane.

[0010] Furthermore, the movement speed of the second wheel foot relative to the support plane increases as the movement speed of the frame relative to the support plane increases, and the movement speed of the second wheel foot relative to the support plane decreases as the movement speed of the frame relative to the support plane decreases.

[0011] Furthermore, a minimum distance from the center of the second wheel foot to the support plane is defined as an offset distance; In step S3, the offset distance increases as the frame yaw angle increases, and the offset distance decreases as the frame yaw speed decreases.

[0012] Furthermore, the second rotating member includes a first connecting section and a second connecting section that are rotatably connected, the first connecting section having a first connecting end and a second connecting end that are opposite to each other, the second connecting section having a third connecting end and a fourth connecting end that are opposite to each other, the first connecting end being rotatably connected to the first rotating member, the second connecting end being rotatably connected to the third connecting end, and the fourth connecting end being rotatably connected to the first wheel foot; In step S3, the second connection end has a first displacement along the Y-axis relative to the first connection end, and the fourth connection end has a second displacement along the Y-axis relative to the third connection end, and the second displacement is opposite to the first displacement.

[0013] Furthermore, the second rotating member includes a first connecting section and a second connecting section that are rotatably connected, the first connecting section is rotatably connected to the frame, and both ends of the second connecting section are rotatably connected to the first connecting section and the first wheel foot respectively; The motion trajectory of the first connecting segment includes a first trajectory segment and two second trajectory segments connected to both ends of the first trajectory segment. In the first trajectory segment, the rotation direction of the second connecting segment relative to the first connecting segment is opposite to the rotation direction of the first connecting segment relative to the frame; in the second trajectory segment, the rotation direction of the second connecting segment relative to the first connecting segment is the same as the rotation direction of the first connecting segment relative to the frame.

[0014] Furthermore, the second wheel group also includes a fourth rotating member, both ends of the fourth rotating member are rotatably connected to the frame and the third rotating member respectively, the third rotating member can rotate around the third rotation axis relative to the fourth rotating member, and the fourth rotating member can rotate around the fourth rotation axis relative to the frame; in the first posture, the fourth rotation axis is parallel to the X-axis direction.

[0015] Furthermore, the wheeled robot has a third posture, in which the first wheeled robot alone supports the frame and moves along the X-axis and / or along the Y-axis. When the wheeled robot switches from the first posture to the third posture, the first rotating member rotates around the second rotating axis relative to the second rotating member; The first wheel foot rolls to drive the wheel-foot robot to move along the X-axis direction; and / or, the first rotating members in the two first wheel groups rotate alternately around the first rotating axis to make the two first wheel feet alternately step along the Y-axis direction.

[0016] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which: Figure 1 2 is a schematic structural diagram of a wheeled-legged robot in a first posture according to an embodiment of the present invention; Figure 2 2 is a schematic structural diagram of the wheeled-legged robot in the second posture according to an embodiment of the present invention; Figure 3 2 is a schematic structural diagram of the wheeled-legged robot in the third posture according to an embodiment of the present invention; Figure numerals: 100, frame; 200, first wheel group; 210, first rotating member; 220, second rotating member; 221, first connecting section; 222, second connecting section; 230, first wheel foot; 300, second wheel group; 310, third rotating member; 311, third connecting section; 312, fourth connecting section; 320, fourth rotating member; 330, second wheel foot. DETAILED DESCRIPTION

[0018] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0019] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0020] In the description of the present invention, "several" means more than one, "plurality" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0021] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0022] In the description of the present invention, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0023] Please refer to Figure 1-3 This embodiment is proposed based on a wheel-foot robot, which includes a frame 100, at least two first wheel groups 200 and at least two second wheel groups 300, the first wheel group 200 and the second wheel group 300 are both arranged on the frame 100; the first wheel group 200 includes a first rotating member 210 that can rotate around a first rotation axis relative to the frame 100, a second rotating member 220 that can rotate around a second rotation axis relative to the first rotating member 210, and a first wheel foot 230 that can be rotatably connected to the second rotating member 220; the second wheel group 300 includes a first rotating member 210 that can rotate around a first rotation axis relative to the first rotating member 210 Regarding the third rotating member 310 of the frame 100 that rotates about the third rotating axis and the second wheel foot 330 that is rotatably connected to the third rotating member 310; the wheeled robot has a first posture and a second posture. When the wheeled robot is in the first posture, the first wheel foot 230 and the second wheel foot 330 jointly support the frame 100, the first rotating axis is parallel to the Z-axis direction, the second rotating axis is parallel to the Y-axis direction, and the third rotating axis is parallel to the Y-axis direction. When the wheeled robot is in the second posture, the second wheel foot 330 alone supports the frame 100 and can move along the Y-axis direction. Among them, any two of the X-axis direction, the Y-axis direction, and the Z-axis direction are perpendicular to each other, and the three are respectively the three coordinate axis directions in three-dimensional space. For example, the X-axis direction can be understood as the length direction (front-back direction) of the wheeled robot, the Y-axis direction can be understood as the width direction (left-right direction) of the wheeled robot, and the Z-axis direction can be understood as the height direction (up-down direction) of the wheeled robot.

[0024] It should be noted that for the above-mentioned wheeled robot, when it is in the second posture, it is supported on the ground or other working surface only by the second wheel foot 330 and is able to move along the Y-axis direction. When the wheeled robot moves along the Y-axis direction, the following problem occurs: the wheeled robot lacks the support of the first wheel foot 230, resulting in the wheeled robot having a tendency to tilt (yaw tendency) along the X-axis direction with the contact point between the second wheel foot 330 and the working surface as the axis. Such a tilting tendency will seriously affect the stability of the wheeled robot when moving along the Y-axis direction. Of course, since there are at least two second wheel feet 330 supported along the Y-axis direction or roughly along the Y-axis direction, the wheeled robot can also be kept stable in the Y-axis direction by adjusting the speed of the wheeled robot moving along the Y-axis direction. Therefore, the difficulty to be solved by this embodiment is how to maintain the stability of the wheeled robot in the X-axis direction.

[0025] Based on the above-mentioned defects, this embodiment provides a control method for a wheeled robot, which includes the following steps: S1, switching the wheeled robot from a first posture to a second posture; wherein, in the process of switching the wheeled robot from the first posture to the second posture, the frame 100 rotates around the third rotation axis, the second rotating member 220 rotates around the second rotation axis, and the first rotating member 210 rotates around the first rotation axis; S2, acquiring the posture information of the frame 100 in real time; S3, controlling the second rotating member 220 to rotate around the second rotation axis based on the posture information of the frame 100 to maintain the dynamic balance of the wheeled robot.

[0026] Following the above, please refer to Figure 2 In the second posture, the first rotation axis is parallel to or approximately parallel to the X-axis, the second rotation axis is parallel to or approximately parallel to the Z-axis, and the third rotation axis is approximately parallel to the X-axis. It should be noted that during movement, due to the yaw of the frame 100 along the X-axis, the directions of the rotation axes of the wheeled robot are not constant. Therefore, this embodiment does not limit the wheeled robot to moving along the Y-axis in a constant second posture. It should be understood that the wheeled robot can be in the second posture at some point during movement along the Y-axis.

[0027] In this embodiment, when the wheeled robot is in the second posture, the second rotating axis is at an angle parallel to or approximately parallel to the Z-axis direction, so that when the second rotating member 220 rotates around the second rotating axis, it can drive the first wheel foot 230 to generate displacement along the X-axis direction, so as to balance the deflection of the frame 100 in the X-axis direction, so that the entire wheeled robot maintains dynamic balance in the X-axis direction when moving along the Y-axis direction.

[0028] It should also be noted that in the first posture, the first and second wheel legs 230 and 330 roll to drive the wheeled robot along the X-axis. The first rotating member 210 can also rotate about a first rotation axis parallel to the Z-axis, driving the first wheel leg 230 to rotate and achieve steering of the wheeled robot. Simultaneously, the second rotating member 220 rotates about a second rotation axis parallel to the Y-axis, adjusting the height of the first wheel leg 230 to accommodate uneven road surfaces. In other words, the first and second rotating members 210 and 220 of this embodiment are inherent steering components of the wheeled robot and are not additional components. Specifically, this embodiment cleverly utilizes the first and second rotating members 210 and 220 of the wheeled robot to drive the second wheel leg 330 to generate displacement along the X-axis in the second posture, thereby balancing the X-axis yaw of the frame 100 and maintaining dynamic balance along the X-axis while the entire wheeled robot moves along the Y-axis.

[0029] For example, the switching from the first posture to the second posture is described as follows: Figure 1-2First, the second wheel foot 330 is kept on the working surface. The frame 100 rotates relative to the second wheel foot 330 about the third rotation axis, thereby lifting the first wheel foot 230 off the working surface until the frame 100 and the second wheel assembly 300 are approximately above the first wheel assembly 200. Simultaneously, during this process, the first rotating member 210 rotates relative to the frame 100 about the first rotation axis, causing the second rotation axis, originally parallel to the Y-axis, to gradually become parallel to or approximately parallel to the Z-axis, thereby completing the transition from the first posture to the second posture.

[0030] Furthermore, each second wheel foot 330 has a contact position with the working surface, and a plane passing through the centers of at least two contact positions and perpendicular to the X-axis direction is defined as the support plane; the posture information of the frame 100 includes the position, movement direction, movement speed, and yaw angle of the frame 100 relative to the support plane. The posture information of the frame 100 can be obtained through sensor measurement or by combining it with algorithm calculation. For example, a sensor such as a gyroscope is provided on the frame 100, and the above parameters can be directly obtained or indirectly obtained through calculation. The installation position of the sensor such as the gyroscope can be adaptively set at the geometric center and / or center of gravity of the frame 100, or other specific locations. Thus, the position information obtained is the information of the geometric center and / or center of gravity of the frame 100, which has greater reference value for controlling the movement of the first wheel foot 230 based on this information in the next step.

[0031] Regarding the posture information of the frame 100, the position of the frame 100 relative to the support plane refers to whether the frame 100 is located on one side or the other side of the support plane, or exactly on the support plane; the movement direction of the frame 100 refers to the movement direction of the frame 100 relative to the support plane, for example, toward or away from the support plane; the movement speed of the frame 100 refers to the movement speed of the frame 100 relative to the support plane; and the yaw angle of the frame 100 refers to the angle between the plane in which the frame 100 is located and the support plane. The plane in which the frame 100 is located can be understood as a plane parallel to the length and width directions of the frame 100.

[0032] It should also be noted that the contact position between the second wheel foot 330 and the working surface may be a contact surface, a contact line or a contact point, and the support plane should be understood as a vertical plane passing through the center of the above-mentioned contact surface, the midpoint of the contact line or the contact point.

[0033] Furthermore, in step S3, when the frame 100 moves to one side of the support plane, the second wheel leg 330 moves to the other side of the support plane. Specifically, the frame 100 and the second wheel leg 330 are located on opposite sides of the support plane, so that the direction of the moment exerted by the gravity of the first wheel assembly 200 on the support plane is opposite to the direction of the moment exerted by the gravity of the frame 100 (and possibly the second wheel assembly 300) on the support plane. This balances the wheeled robot's yaw along the X-axis and maintains dynamic balance.

[0034] Furthermore, in step S3, the direction of movement of the second wheel foot 330 relative to the support plane is opposite to the direction of movement of the frame 100 relative to the support plane. The speed of movement of the second wheel foot 330 relative to the support plane increases as the speed of movement of the frame 100 relative to the support plane increases, and the speed of movement of the second wheel foot 330 relative to the support plane decreases as the speed of movement of the frame 100 relative to the support plane decreases. The minimum distance from the center of the second wheel foot 330 to the support plane is defined as the offset distance; in step S3, the offset distance increases as the yaw angle of the frame 100 increases, and decreases as the yaw speed of the frame 100 decreases.

[0035] First, it should be noted that the total weight of the frame 100 and the second wheel assembly 300 is constant, but as the frame 100 yaws, the lever arm between its center of gravity and the support plane continuously changes. Similarly, since the weight of the first wheel assembly 200 is constant, but as the first wheel assembly 200 moves, the lever arm between its center of gravity and the support plane continuously changes. Therefore, in order to make the torque of the frame 100 and the second wheel assembly 300 on the support plane and the force of the first wheel assembly 200 on the support plane offset each other, it is necessary to make the first lever arm of the first wheel assembly 200 on the support plane correlate with the second lever arm of the frame 100 and the second wheel foot 330 on the support plane, that is, the first lever arm increases as the second lever arm increases, and the first lever arm decreases as the second lever arm decreases.

[0036] Following the above, in order to achieve the change of the first force arm as the second force arm changes, it is necessary to control the position, movement direction, movement speed and displacement of the second wheel foot 330 to change with the change of the frame 100, and finally achieve the dynamic balance of the wheel-foot robot.

[0037] It should also be noted that because the first wheel foot 230 accounts for the vast majority of the weight of the first wheel assembly 200, and the second wheel assembly 300 has a very small range of motion during the yaw of the frame 100, the influence of this portion of weight can be ignored. Therefore, the speed of the first wheel foot 230 can be directly correlated with the speed of the frame 100. Furthermore, although the weight of the first wheel foot 230 is less than the weight of the entire second wheel assembly 300, because the range of motion of the first wheel foot 230 is greater than that of the second wheel assembly 300, the weight of the portion of the first wheel assembly 200 excluding the first wheel foot 230 and the weight of the second wheel assembly 300 can offset each other in maintaining dynamic balance.

[0038] Furthermore, the second rotating member 220 includes a first connecting segment 221 and a second connecting segment 222 that are rotatably connected, the first connecting segment 221 has a first connecting end and a second connecting end that are opposite to each other, the second connecting segment 222 has a third connecting end and a fourth connecting end that are opposite to each other, the first connecting end is rotatably connected to the first rotating member 210, the second connecting end is rotatably connected to the third connecting end, and the fourth connecting end is rotatably connected to the first wheel foot 230; in step S3, the second connecting end has a first displacement along the Y-axis direction relative to the first connecting end, and the fourth connecting end has a second displacement along the Y-axis direction relative to the third connecting end, and the second displacement is opposite to the direction of the first displacement.

[0039] Specifically, when the first connecting segment 221 rotates relative to the first rotating member 210, the second connecting segment 222 can also rotate relative to the first connecting segment 221. When the first connecting segment 221 rotates, causing the second connecting end to move outward, generating a first displacement in the positive direction of the Y-axis, the second connecting segment 222 can rotate relative to the first connecting segment 221, causing the first wheel foot 230 connected to the fourth connecting end to move inward, generating a second displacement in the negative direction of the Y-axis. This second displacement partially or completely offsets the first displacement, allowing the motion trajectory of the first wheel foot 230 to move closer to the first connecting end. This shortens the distance between the first wheel foot 230 and the first connecting end. This distance constitutes the lever arm that drives the movement of the first wheel foot 230. Shortening this lever arm reduces the load on the actuator that drives the first connecting end to rotate, thereby enabling it to drive the first rotating member 210 with less force, facilitating more precise control of the position of the first wheel foot 230 and enhancing the stability of the wheeled robot.

[0040] It should also be noted that during the movement of the wheeled robot, the motion trajectories of the two first wheel legs 230 are not necessarily completely symmetrical along the Y-axis, and the torques exerted by the two first wheel legs 230 on the frame 100 in the Y-axis direction cannot be completely offset. Although the two second wheel legs 330 provide lateral support to the frame 100 in the Y-axis direction, if the torque difference between the two first wheel legs 230 and the frame 100 in the Y-axis direction is too large, the wheeled robot still faces the risk of tipping over in the Y-axis direction.

[0041] To overcome the above-mentioned drawbacks, this embodiment utilizes the synergistic effect of the first connecting segment 221 and the second connecting segment 222 to bring the motion trajectory of the first wheel foot 230 closer to the frame 100, thereby reducing the moment arm of the first wheel foot 230 on the frame 100 and the moment of force in the Y-axis direction exerted by the first wheel foot 230 on the frame 100. Thus, by reducing the magnitude of the moment of force exerted by each first wheel foot 230 on the frame 100 in the Y-axis direction, the difference between the two first moments is reduced. Ultimately, the lateral moment in the Y-axis direction exerted on the frame 100 can be offset by the lateral support force of the two second wheel feet 330, thereby preventing the wheeled robot from tipping over in the Y-axis direction.

[0042] Furthermore, the second rotating member 220 includes a first connecting section 221 and a second connecting section 222 that are rotatably connected. The first connecting section 221 is rotatably connected to the frame 100, and the two ends of the second connecting section 222 are rotatably connected to the first connecting section 221 and the first wheel foot 230 respectively; the motion trajectory of the first connecting section 221 includes a first trajectory section and two second trajectory sections connected to the two ends of the first trajectory section. In the first trajectory section, the rotation direction of the second connecting section 222 relative to the first connecting section 221 is opposite to the rotation direction of the first connecting section 221 relative to the frame 100; in the second trajectory section, the rotation direction of the second connecting section 222 relative to the first connecting section 221 is the same as the rotation direction of the first connecting section 221 relative to the frame 100.

[0043] Specifically, during the first trajectory segment, the second connecting segment 222 and the first connecting segment 221 rotate in opposite directions, bringing the first wheel foot 230 closer to the frame 100. During the second trajectory segment, the second connecting segment 222 and the first connecting segment 221 rotate in the same direction. When the frame 100 is tilted too far, the first wheel foot 230 needs to extend further. In this case, the first connecting segment 221 and the second connecting segment 222 rotate in the same direction, driving the first wheel foot 230 further away from the frame 100. This increases the moment arm between the first wheel foot 230 and the frame 100, thereby increasing the torque exerted by the first wheel foot 230 on the frame 100.

[0044] Furthermore, the second wheel group 300 also includes a fourth rotating member 320, the two ends of which are rotatably connected to the frame 100 and the third rotating member 310 respectively, the third rotating member 310 can rotate around the third rotation axis relative to the fourth rotating member 320, and the fourth rotating member 320 can rotate around the fourth rotation axis relative to the frame 100; in the first posture, the fourth rotation axis is parallel or approximately parallel to the X-axis direction; in the second posture, the third rotation axis is parallel or approximately parallel to the X-axis direction, and the fourth rotation axis is parallel or approximately parallel to the Z-axis direction.

[0045] Specifically, in the process of the wheeled robot switching from the first posture to the second posture, the fourth rotating member 320 drives the frame 100 to rotate around the third rotation axis compared with the third rotating member 310, until the fourth rotation axis rotates from parallel or approximately parallel to the X-axis direction to parallel or approximately parallel to the Z-axis direction, and then the fourth rotating shaft member rotates around the fourth rotation axis compared to the frame 100, until the third rotation axis rotates from parallel or approximately parallel to the Y-axis direction to parallel or approximately parallel to the X-axis direction, and finally the rolling directions of the two second wheel feet 330 are on the same straight line.

[0046] For further information, please refer to Figure 3 The wheeled robot also has a third posture. In the third posture, the first wheeled foot 230 independently supports the frame 100 and moves along the X-axis and / or along the Y-axis. During the process of switching the wheeled robot from the first posture to the third posture, the first rotating member 210 rotates about the second rotation axis relative to the second rotating member 220. The first wheeled foot 230 rolls to drive the wheeled robot along the X-axis. And / or, the first rotating members 210 in the two first wheel groups 200 rotate alternately about the first rotation axis, causing the two first wheeled feet 230 to alternately step along the Y-axis. In the third posture, the two first wheeled feet 230 are independently supported on the work surface, and the two second wheeled feet 330 are lifted off the work surface. At this time, the rolling of the first wheeled feet 230 can drive the entire wheeled robot to move along its rolling direction (X-axis direction).

[0047] At the same time, the two first wheel legs 230 can also move in a striding manner along the Y-axis. Specifically, one of the first wheel legs 230 maintains contact with the work surface, while the other first wheel leg 230 is lifted off the ground. The first rotating member 210 then rotates about the first rotation axis, causing the lifted first wheel leg 230 to move toward or away from the other first wheel leg 230. The lifted first wheel leg 230 is then lowered and supported on the work surface, and the other first wheel leg 230 is then lifted off the work surface, and the above steps are repeated. This allows the wheeled robot to achieve striding movement along the Y-axis.

[0048] Furthermore, the third rotating member 310 includes a rotatably connected third connecting segment 311 and a fourth connecting segment 312. The end of the third connecting segment 311 away from the fourth connecting segment 312 is rotatably connected to the fourth rotating member 320. The second wheel foot 330 is rotatably connected to the end of the fourth connecting segment 312 away from the third connecting segment 311. Specifically, the relative rotation of the third connecting segment 311 and the fourth connecting segment 312 can adjust the height of the second wheel foot 330, thereby adapting to uneven road surfaces and ensuring stable movement of the wheeled robot.

[0049] While the embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to the embodiments described above. Various modifications may be made within the scope of knowledge possessed by a person skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof may be combined with one another unless there is a conflict.

Claims

1. A control method for a wheeled robot, characterized in that: The wheel-foot robot includes a frame, at least two first wheel groups and at least two second wheel groups, wherein the first wheel group and the second wheel group are both arranged on the frame; the first wheel group includes a first rotating member that can rotate relative to the frame around a first rotating axis, a second rotating member that can rotate relative to the first rotating member around a second rotating axis, and a first wheel foot that can be rotatably connected to the second rotating member; the second wheel group includes a third rotating member that can rotate relative to the frame around a third rotating axis and a second wheel foot that can be rotatably connected to the third rotating member; The wheeled robot has a first posture and a second posture. When the wheeled robot is in the first posture, the first wheeled foot and the second wheeled foot jointly support the frame, the first rotation axis is parallel to the Z-axis direction, the second rotation axis is parallel to the Y-axis direction, and the third rotation axis is parallel to the Y-axis direction; when the wheeled robot is in the second posture, the second wheeled foot alone supports the frame and can move along the Y-axis direction; The control method comprises the steps of: S1. Switching the wheeled robot from the first posture to the second posture; wherein, during the process of switching the wheeled robot from the first posture to the second posture, the frame rotates around the third rotation axis, the second rotating member rotates around the second rotation axis, and the first rotating member rotates around the first rotation axis; S2. Acquire the posture information of the frame in real time; S3. Control the second rotating member to rotate around the second rotating axis according to the frame posture information to maintain the dynamic balance of the wheeled robot.

2. The control method of the wheeled robot according to claim 1, characterized in that: Each of the second wheel feet has a contact position with the working surface, and a plane passing through the centers of at least two of the contact positions and perpendicular to the X-axis direction is defined as a support plane; The posture information of the frame includes the position, movement direction, movement speed and yaw angle of the frame relative to the support plane.

3. The control method of the wheeled robot according to claim 2, characterized in that: In step S3, when the frame moves to one side of the support plane, the second wheel foot moves to the other side of the support plane.

4. The control method of the wheeled robot according to claim 2, characterized in that: In step S3, the movement direction of the second wheel foot relative to the support plane is opposite to the movement direction of the frame relative to the support plane.

5. The control method of the wheeled robot according to claim 2, characterized in that: The movement speed of the second wheel foot relative to the support plane increases as the movement speed of the frame relative to the support plane increases, and the movement speed of the second wheel foot relative to the support plane decreases as the movement speed of the frame relative to the support plane decreases.

6. The control method of the wheeled robot according to claim 2, characterized in that: defining the minimum distance from the center of the second wheel foot to the support plane as the offset distance; In step S3, the offset distance increases as the frame yaw angle increases, and the offset distance decreases as the frame yaw speed decreases.

7. The control method of the wheeled robot according to claim 1, characterized in that: The second rotating member includes a first connecting section and a second connecting section that are rotatably connected, the first connecting section having a first connecting end and a second connecting end that are opposite to each other, the second connecting section having a third connecting end and a fourth connecting end that are opposite to each other, the first connecting end being rotatably connected to the first rotating member, the second connecting end being rotatably connected to the third connecting end, and the fourth connecting end being rotatably connected to the first wheel foot; In step S3, the second connection end has a first displacement along the Y-axis relative to the first connection end, and the fourth connection end has a second displacement along the Y-axis relative to the third connection end, and the second displacement is opposite to the first displacement.

8. The control method of the wheeled robot according to claim 1, characterized in that: The second rotating member includes a first connecting section and a second connecting section that are rotatably connected, the first connecting section is rotatably connected to the frame, and both ends of the second connecting section are rotatably connected to the first connecting section and the first wheel foot respectively; The motion trajectory of the first connecting segment includes a first trajectory segment and two second trajectory segments connected to both ends of the first trajectory segment. In the first trajectory segment, the rotation direction of the second connecting segment relative to the first connecting segment is opposite to the rotation direction of the first connecting segment relative to the frame; in the second trajectory segment, the rotation direction of the second connecting segment relative to the first connecting segment is the same as the rotation direction of the first connecting segment relative to the frame.

9. The control method of the wheeled robot according to claim 1, characterized in that: The second wheel group also includes a fourth rotating member, both ends of which are rotatably connected to the frame and the third rotating member respectively, the third rotating member can rotate around the third rotation axis relative to the fourth rotating member, and the fourth rotating member can rotate around the fourth rotation axis relative to the frame; in the first posture, the fourth rotation axis is parallel to the X-axis direction.

10. The control method of the wheeled robot according to claim 1, characterized in that: The wheeled robot further has a third posture, in which the first wheeled foot alone supports the frame and moves along the X-axis direction and / or along the Y-axis direction; When the wheeled robot switches from the first posture to the third posture, the first rotating member rotates around the second rotating axis relative to the second rotating member; The first wheel foot rolls to drive the wheel-foot robot to move along the X-axis direction; and / or, the first rotating members in the two first wheel groups rotate alternately around the first rotating axis to make the two first wheel feet alternately step along the Y-axis direction.

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