Robot control method and device, chip product, equipment and storage medium

Abstract

A control method and device of a robot, a chip product, an equipment and a storage medium, relate to the technical field of artificial intelligence. The method comprises: for a robot having an inner mechanical leg and an outer mechanical leg connected to a body through a hip joint, the hip joint corresponding to the inner mechanical leg is located between the hip joints corresponding to the two outer mechanical legs, and at least one mechanical leg of the robot has a pair of coaxial mechanical wheels and a mechanical foot arranged away from the foot of the hip joint; in the case that the robot stands on a support surface through the mechanical foot assisting the mechanical wheel, the mechanical foot coaxial with the mechanical wheel is moved to be separated from the support surface, so that the robot can stand on the support surface only through the mechanical wheel. For the wheel-legged robot with the mechanical foot, the application adjusts the mechanical foot to realize the switching of the robot from the foot support state to the wheel support state, so that the robot can perform different tasks by switching the state, and the flexibility of the robot is improved.

Description

Technical Field

[0001] This application relates to the field of artificial intelligence technology, and in particular to a robot control method, device, chip product, equipment, and storage medium. Background Technology

[0002] With the development of robot control technology, some organizations and research institutions have successively launched wheel-legged robots with mechanical feet (hereinafter referred to as wheel-leg hybrid robots). Wheel-leg hybrid robots can not only rely on mechanical wheels to perform wheeled movements such as gliding and gait walking, but also rely on mechanical wheels and mechanical feet to stably perform legged movements such as gait walking and climbing stairs.

[0003] However, for some complex scenarios involving both wheeled and legged motion, how to enable hybrid legged and wheeled robots to switch from legged to wheeled motion is a problem that urgently needs to be solved. Summary of the Invention

[0004] This application provides a robot control method, apparatus, chip product, device, and storage medium. The technical solutions provided in this application may include the following.

[0005] According to one aspect of the embodiments of this application, a robot control method is provided. The robot includes a body, two outer mechanical legs connected to the body via hip joints, and at least one inner mechanical leg. The hip joint corresponding to the at least one inner mechanical leg is located between the hip joints corresponding to the two outer mechanical legs. The rotation centers of the hip joints corresponding to the outer mechanical legs and the rotation centers of the hip joints corresponding to the inner mechanical legs are located in the same vertical plane. At least one of the robot's mechanical legs has a pair of coaxial mechanical wheels and a mechanical foot disposed at its foot portion away from the hip joint. The method includes:

[0006] The robot stands on a support surface in a foot-supported state, wherein, in the foot-supported state, the robot stands upright with the assistance of the mechanical wheels via the mechanical feet;

[0007] The mechanical foot is moved away from the support surface, so that the robot stands on the support surface from the foot-supported state to the wheel-supported state, wherein in the wheel-supported state, the robot stands only on the mechanical wheels.

[0008] According to one aspect of the embodiments of this application, a control device for a robot is provided. The robot includes a body, two outer mechanical legs connected to the body via hip joints, and at least one inner mechanical leg. The hip joint corresponding to the at least one inner mechanical leg is located between the hip joints corresponding to the two outer mechanical legs. The rotation centers of the hip joints corresponding to the outer mechanical legs and the rotation centers of the hip joints corresponding to the inner mechanical legs are located in the same vertical plane. At least one of the robot's mechanical legs has a pair of coaxial mechanical wheels and a mechanical foot disposed at its foot portion away from the hip joint. The device includes:

[0009] A robot standing module is used to stand on a support surface in a foot-supported state, wherein, in the foot-supported state, the robot stands by means of mechanical feet assisted by mechanical wheels;

[0010] A state transition module is used to move the mechanical foot away from the support surface, so that the robot transitions from the foot-supported state to the wheel-supported state and stands on the support surface. In the wheel-supported state, the robot stands only on the mechanical wheels.

[0011] According to one aspect of the embodiments of this application, a chip product is provided, wherein a computer program is stored in the chip product, the computer program being loaded and executed by a processor to implement the above-described robot control method.

[0012] According to one aspect of the embodiments of this application, a computer device is provided, the computer device including a processor and a memory, the memory storing a computer program, the computer program being loaded and executed by the processor to implement the above-described robot control method.

[0013] According to one aspect of the embodiments of this application, a computer-readable storage medium is provided, wherein a computer program is stored in the storage medium, the computer program being loaded and executed by a processor to implement the above-described robot control method.

[0014] According to one aspect of the embodiments of this application, a computer program product is provided, comprising a computer program stored in a computer-readable storage medium. A processor of a computer device reads the computer program from the computer-readable storage medium and executes the computer program, causing the computer device to perform the robot control method described above.

[0015] The technical solutions provided in this application embodiment may have the following beneficial effects:

[0016] For a robot with an inner and outer mechanical leg connected to the body via a hip joint, since the hip joint corresponding to the inner mechanical leg is located between the hip joints corresponding to the two outer mechanical legs, and at least one mechanical leg has a pair of coaxial mechanical wheels and mechanical feet on its foot away from the hip joint, when the robot stands on the support surface with the assistance of the mechanical feet and mechanical wheels, the inner and outer mechanical legs can work together to move the mechanical feet coaxial with the mechanical wheels away from the support surface. This allows the robot to stand on the support surface solely by the mechanical wheels, thus entering the wheel-supported state. This gives wheel-legged robots with mechanical feet the ability to switch from a foot-supported state to a wheel-supported state, allowing the robot to perform different tasks by switching states, thereby improving the robot's flexibility. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of a robot control system provided in one embodiment of this application;

[0019] Figure 2 This is a schematic diagram of a quadrupedal wheeled hybrid robot provided in one embodiment of this application;

[0020] Figure 3 This is a schematic diagram of a four-wheel support state and a four-legged support state provided in one embodiment of this application;

[0021] Figure 4 This is a flowchart of a robot control method provided in one embodiment of this application;

[0022] Figure 5 This is a flowchart of a robot control method provided in another embodiment of this application;

[0023] Figure 6 This is a schematic diagram illustrating the switching of the wheel support state to the ready state according to an embodiment of this application;

[0024] Figure 7 This is a schematic diagram illustrating the switching from a preparation state to a first state according to an embodiment of this application;

[0025] Figure 8 This is a schematic diagram illustrating the transition from a first state to a second state according to an embodiment of this application;

[0026] Figure 9This is a schematic diagram illustrating the switching from a second state to a wheel support state according to an embodiment of this application;

[0027] Figure 10 This is a schematic diagram illustrating the switching from a wheel-supported state to a wheel-movement state according to an embodiment of this application;

[0028] Figure 11 This is a schematic diagram illustrating the switching from a four-legged support state to a four-wheel support state according to an embodiment of this application;

[0029] Figure 12 This is a block diagram of a robot control device provided in one embodiment of this application;

[0030] Figure 13 This is a block diagram of a robot control device provided in another embodiment of this application;

[0031] Figure 14 This is a simplified structural block diagram of a computer device provided in one embodiment of this application. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0033] The technical solutions provided in this application mainly relate to robotics within artificial intelligence technology, particularly intelligent robot control. A robot is a mechanical and electronic device that combines mechanical transmission and modern microelectronics technology to mimic certain human skills. Robots have evolved based on electronic, mechanical, and information technologies. A robot doesn't necessarily have to resemble a human; as long as it can autonomously complete tasks and commands given to it by humans, it belongs to the robot family. A robot is an automated machine possessing some intelligent abilities similar to humans or other living beings, such as perception, planning, movement, and coordination. It is a highly flexible automated machine. With the development of computer technology and artificial intelligence technology, robots have greatly improved in terms of function and technology. Mobile robots and technologies such as robot vision and touch are typical examples.

[0034] The technical solutions provided in this application embodiment can be executed by computer equipment, which can refer to electronic devices with data computing, processing and storage capabilities.

[0035] Optionally, the computer device can be a PC (Personal Computer) device such as a desktop computer or laptop computer used to control the robot; it can also be a server used to control the robot. The server can be a standalone physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing cloud computing services. The computer device and the robot can be connected via physical lines, networks, etc. For example, refer to... Figure 1 In the robot control system 100, the computer device 101 can determine the desired task of the robot 103 (e.g., the desired task may include the desired acceleration / desired joint angle of each part of the robot 103 in the robot 103's operating space) based on the robot 103's reference movement trajectory set (e.g., including the reference movement trajectory of each part of the robot 103, including the reference position at each control moment). Then, based on the desired task, the computer device 101 calculates the desired joint torque set corresponding to the robot 103, and controls the robot 103 (e.g., each joint motor) to move via the network 102 according to the desired joint torque set. For example, the computer device 101 can control the robot 103 to switch from a foot-supported state to a wheel-supported state on the support surface based on the robot 103's desired joint torque set, so that the robot 103 can switch from being able to perform foot-based movements to being able to perform wheel-based movements. In the wheel-supported state, the robot 103 stands only on mechanical wheels; in the foot-supported state, the robot 103 stands on mechanical feet assisted by mechanical wheels.

[0036] Optionally, the computer device can also be the robot itself, that is, the execution entity of each step in the technical solution provided in this application embodiment is a robot. For example, refer to... Figure 1 The computer device 101 can send the desired task (or reference movement trajectory set) of the robot 103 to the robot 103 via the network 102. The robot 103 calculates the corresponding desired joint torque set based on the desired task (or reference movement trajectory set) and then moves according to the desired joint torque set. Optionally, the robot 103 can also automatically plan the reference movement trajectory set according to the real environment and calculate the desired task corresponding to the reference movement trajectory set, so as to switch the support state in the real environment (such as switching from foot support state to wheel support state) to perform different tasks. This embodiment of the application does not limit this.

[0037] In some embodiments, the robot in this application may include a foot-wheel hybrid robot. A foot-wheel hybrid robot refers to a wheel-legged robot with mechanical feet; a wheel-legged robot refers to a legged robot with wheels as its feet (i.e., a robot that moves based on mechanical legs). Optionally, a foot-wheel hybrid robot refers to a legged robot with a pair of mechanical wheels and mechanical feet at its feet; this application does not limit this. For example, refer to... Figure 1 Robot 103 is a quadrupedal wheel-machine hybrid robot. Robot 103 has four mechanical legs, and each mechanical leg has a pair of coaxial mechanical wheels and a mechanical foot. The wheel-machine hybrid robot can perform wheeled movements such as gliding, walking, climbing stairs, overcoming obstacles, waving, picking up objects, and carrying using only the mechanical wheels. It can also perform legged movements such as walking, climbing stairs, overcoming obstacles, stepping in place, waving, picking up objects, and carrying using the mechanical feet in conjunction with the mechanical wheels. This embodiment of the application does not limit this specific capability.

[0038] In one example, reference Figure 1 The foot-wheel hybrid robot (i.e., robot 103) in this embodiment may include a body 106, two outer mechanical legs connected to the body 106 via hip joints, and at least one inner mechanical leg. The two outer mechanical legs of robot 103 form a first mechanical leg group 104, and the at least one inner mechanical leg of robot 103 may form a second mechanical leg group 105. The two outer mechanical legs are located on both sides of the central axis (i.e., sagittal plane) of robot 103. Optionally, the two outer mechanical legs may be the two outermost mechanical legs of robot 103.

[0039] The robotic legs of robot 103 are arranged side by side, meaning that the rotation centers of the hip joints corresponding to the outer robotic legs and the inner robotic legs are located in the same vertical plane. For example, the rotation axes of the hip joints corresponding to the first robotic leg group 104 and the second robotic leg group 105 are located in the same vertical plane. Here, the rotation center refers to a point on the rotation axis of the hip joint.

[0040] Optionally, at least one inner mechanical leg's hip joint is located between the two outer mechanical legs' hip joints, meaning at least one inner mechanical leg is entirely located between the two outer mechanical legs. For example, in the case where the two mechanical leg groups 105 include two inner mechanical legs, the two outer mechanical legs in the first mechanical leg group 104 can be respectively positioned on both sides of the second mechanical leg group 105, meaning the two inner mechanical legs in the second mechanical leg group 105 can be positioned between the two outer mechanical legs in the first mechanical leg group 104.

[0041] For example, robot 103 can be a quadrupedal wheeled hybrid robot, such as robot 103 including two outer mechanical legs and two inner mechanical legs; robot 103 can also be a tripedal wheeled hybrid robot, such as robot 103 including two outer mechanical legs and one inner mechanical leg, and this application embodiment does not limit this. Robot 103 can stand on the support surface by means of mechanical wheels on the outer or inner mechanical legs, or slide on the support surface by means of mechanical wheels on the outer or inner mechanical legs, or move on the support surface by controlling the alternating swing of the first mechanical leg group 104 and the second mechanical leg group 105 (i.e., gait walking), and can switch between legged and wheeled movement by rotating the mechanical feet, and this application embodiment does not limit this. Among them, the mechanical feet of robot 103 can assist the mechanical wheels to make robot 103 perform legged movement more stably.

[0042] Optionally, the waist of the body 106 is provided with pitch and yaw joints, which can control the rotation of the body 106 (such as forward and backward pitch, left and right yaw). The rotation of the mechanical legs can be controlled by the hip joints, and each mechanical leg can extend and retract independently. In one example, the mechanical legs corresponding to the first mechanical leg group 104 move synchronously, and the mechanical legs corresponding to the second mechanical leg group 105 move synchronously; the mechanical wheels corresponding to the first mechanical leg group 104 move synchronously, and the mechanical wheels corresponding to the second mechanical leg group 105 move synchronously.

[0043] Optionally, in the foot-wheel hybrid robot, at least one of the mechanical legs has a pair of coaxial mechanical wheels and mechanical feet on the foot portion away from the hip joint. That is, there is at least one foot whose corresponding mechanical wheel's rotation axis and its corresponding mechanical foot's rotation axis are on the same straight line. For example, all the mechanical legs of robot 103 are provided with a pair of coaxial mechanical wheels and mechanical feet; or, some of the mechanical legs of robot 103 are provided with a pair of coaxial mechanical wheels and mechanical feet.

[0044] For example, taking a quadrupedal wheel-driven hybrid robot as an example, each of the corresponding mechanical legs of the quadrupedal wheel-driven hybrid robot can be equipped with a pair of coaxial mechanical wheels and mechanical feet; or, for the two mechanical leg groups corresponding to the quadrupedal wheel-driven hybrid robot, only one of the mechanical leg groups has a pair of coaxial mechanical wheels and mechanical feet on each mechanical leg; or, for the two mechanical leg groups corresponding to the quadrupedal wheel-driven hybrid robot, each mechanical leg group has one mechanical leg corresponding to a pair of coaxial mechanical wheels and mechanical feet; or, for each mechanical leg corresponding to the quadrupedal wheel-driven hybrid robot, only one mechanical leg has a pair of coaxial mechanical wheels and mechanical feet. The embodiments of this application do not limit this.

[0045] Each mechanical wheel can be driven independently, and each mechanical foot can rotate independently. The mechanical feet can be located on the left or right side of the mechanical wheels, or the mechanical wheels can be located in the hollowed-out area at the base of the mechanical feet in a hollowed-out style. This application embodiment does not limit this.

[0046] This application does not limit the dimensions of the mechanical wheels and mechanical feet. For example, all mechanical wheels may have the same diameter, and all mechanical feet may have the same length. The length of the mechanical feet may be 1.5 times, 2 times, or the diameter of the mechanical wheels. This application also does not limit the style of the mechanical feet. For example, the style of the mechanical feet may include at least one of the following: foot-like style, rectangular style, and triangular style.

[0047] Mechanical feet can be used to assist mechanical wheels, enabling the robot to stand more stably on the support surface. Optionally, when mechanical feet are not needed, they can rotate to coincide with the mechanical legs, or rotate to be perpendicular to the mechanical legs, or rotate to any angle that does not affect the contact between the mechanical feet and the support surface; this embodiment does not limit this. When mechanical feet are needed, they can rotate to contact the support surface, so that together with the mechanical wheels, they can support the robot standing on the support surface.

[0048] For example, refer to Figure 1 Taking a quadrupedal wheel-driven hybrid robot as an example, if each of the mechanical legs of robot 103 is equipped with a pair of coaxial mechanical wheels and mechanical feet, and any mechanical wheel is in contact with the support surface, the mechanical foot coaxial with the mechanical wheel can be used to assist the mechanical wheel in supporting robot 103 to stand. Alternatively, if only one set of mechanical legs is equipped with a pair of coaxial mechanical wheels and mechanical feet, and there is no mechanical leg set without mechanical feet for support, then robot 103 stands solely on the mechanical wheels corresponding to the mechanical leg set. If the robotic legs are used for support, the robot 103 can stand upright by relying on the corresponding mechanical wheels and mechanical feet of the robotic leg assembly. Alternatively, if only one robotic leg is equipped with a pair of coaxial mechanical wheels and a mechanical foot, and there is no robotic leg assembly with mechanical feet for support, the robot 103 can stand upright solely by relying on the corresponding mechanical wheels of the robotic leg assembly. If there is a robotic leg assembly with mechanical feet for support, the robot 103 can stand upright by relying on the corresponding mechanical wheels and a mechanical foot of the robotic leg assembly. This application embodiment does not limit this. For ease of explanation, the following will use the example of each foot of the robot being equipped with a pair of coaxial mechanical wheels and a mechanical foot to illustrate the technical solution provided in this application embodiment.

[0049] In some embodiments, reference Figure 2This is a schematic diagram of the structure of a quadrupedal wheeled hybrid robot provided in one embodiment of this application. The quadrupedal wheeled hybrid robot 200 may include: a body (including a waist 207, a torso 208, a head 209, and an upper limb 210), a hip joint 211, and mechanical legs (such as an outer mechanical leg 201 and an inner mechanical leg 202).

[0050] The quadrupedal wheeled hybrid robot 200 has four mechanical legs: two outer mechanical legs 201 (referred to as the first mechanical leg group) and two inner mechanical legs 202 (referred to as the second mechanical leg group). The two inner mechanical legs 202 are located between the two outer mechanical legs 201. All four mechanical legs can move along... Figure 2 The indicated directions (double-headed arrows) allow for independent extension and retraction (achieved by corresponding telescopic joints). The four mechanical legs can be symmetrically distributed on both sides of the sagittal plane 206.

[0051] Each of the four mechanical legs is equipped with a pair of coaxial mechanical wheels 203 and mechanical feet 204. That is, the rotation axis corresponding to the mechanical wheel 203 and the rotation axis corresponding to the mechanical foot 204 are located on the same straight line. The mechanical foot 204 is installed on the outside of the mechanical wheel 203. Each mechanical wheel 203 can be driven independently (by the corresponding wheel joint), and each mechanical foot 204 can also be driven independently (by the corresponding ankle joint).

[0052] The quadrupedal wheeled hybrid robot 200 can stand on the mechanical wheels on the two inner mechanical legs 202 or the two outer mechanical legs 201 to be in a two-wheel support state; the quadrupedal wheeled hybrid robot 200 can also stand on the mechanical wheels on the two inner mechanical legs 202 and the two outer mechanical legs 201 at the same time to be in a four-wheel support state. The two-wheel support state and the four-wheel support state can be collectively referred to as the wheel support state, and the embodiments of this application do not limit this.

[0053] The quadrupedal wheel-driven hybrid robot 200 can stand on two inner mechanical legs 202 with mechanical wheels and mechanical feet or on two outer mechanical legs 201 with mechanical wheels and mechanical feet, thus being in a bipedal support state. The quadrupedal wheel-driven hybrid robot 200 can also stand on two inner mechanical legs 202 with mechanical wheels and mechanical feet, as well as on two outer mechanical legs 201 with mechanical wheels and mechanical feet, thus being in a quadrupedal support state. The bipedal support state and the quadrupedal support state can be collectively referred to as the foot support state, and this application embodiment does not limit this.

[0054] In the embodiments of this application, when at least one mechanical foot assists the mechanical wheel in supporting the robot to stand, it can be determined that the robot is in a foot-supported state; when the robot is supported to stand only by the mechanical wheel, it can be determined that the robot is in a wheel-supported state.

[0055] Alternatively, the two inner mechanical legs 202 can be implemented as a single unit, that is, the quadrupedal wheel hybrid robot 200 can be implemented as a tripedal wheel hybrid robot with only one inner mechanical leg.

[0056] Each robotic leg, at its other end away from the foot, is connected to a hip joint 211. Each robotic leg can rotate around its respective hip joint 211 and maintain linkage. In this embodiment, the rotation axes of the hip joints 211 corresponding to the quadrupedal wheeled hybrid robot 200 are located in the same vertical plane 205, and the rotation planes of the robotic legs corresponding to the quadrupedal wheeled hybrid robot 200 are parallel. The hip joints 211 corresponding to the two inner robotic legs 202 are located between the hip joints 211 corresponding to the two outer robotic legs 201, and the four hip joints 211 are symmetrically distributed on both sides of the sagittal plane 206.

[0057] Optionally, the hip joints 211 of the quadrupedal wheeled hybrid robot 200 can be coaxial, meaning that the rotation axes of the hip joints 211 are located on the same straight line. Alternatively, the hip joints 211 of the quadrupedal wheeled hybrid robot 200 can be non-coaxial. For example, the hip joints 211 corresponding to the two inner mechanical legs 202 can be coaxial, and the hip joints 211 corresponding to the two outer mechanical legs 201 can be coaxial, but the hip joints 211 corresponding to the two inner mechanical legs 202 are not coaxial with the hip joints 211 corresponding to the two outer mechanical legs 201.

[0058] In one example, the hip joints 211 corresponding to the two outer robotic legs 201 share the same drive motor, so that the two outer robotic legs 201 move synchronously; the hip joints 211 corresponding to the two inner robotic legs 202 share the same drive motor, so that the two inner robotic legs 202 move synchronously. In a feasible example, each hip joint 211 corresponding to the quadrupedal wheeled hybrid robot 200 can also be driven independently by its respective drive motor, and this application embodiment does not limit this.

[0059] The quadrupedal wheeled hybrid robot 200 may include a waist 207, a torso 208, a head 209, and upper limbs 210. Each hip joint 211 of the quadrupedal wheeled hybrid robot 200 is connected to the same end of the waist 207, and the other end of the waist 207 is connected to one end of the torso 208. The waist 207 has two rotation axes: a pitch rotation axis (which may have a corresponding pitch joint) that allows the torso 208 to pitch, and a lateral rotation axis (which may have a corresponding lateral joint) that allows the torso 208 to sway. The lateral joint is connected in series with the pitch joint and is located above the pitch joint, connected to the torso 208. In this embodiment, rotating the robot body refers to rotating the pitch joint around the pitch rotation axis, causing the torso 208 to rotate.

[0060] The other end of the torso 208 is connected to the head 209 and the upper limb 210, which can be a multi-degree-of-freedom upper limb. In some embodiments, an end effector, such as a robotic gripper or a suction cup, is deployed on the upper limb 210. Data acquisition devices, such as image acquisition devices, video recording devices, and IMUs (Inertial Measurement Units), can be deployed in the head 209 to perceive the real environment. The IMU can be placed at the geometric center of the torso 208, the center point of the hip joint, etc., and can be used to measure the actual acceleration, actual angular velocity, actual Euler angles, actual position, actual angle, and actual angular velocity of the torso 208.

[0061] In some feasible examples, a workstation can also be deployed in the quadrupedal wheeled hybrid robot 200. This workstation can be used to control the movement of various parts of the robot, such as controlling the joints to make the parts move. This workstation can be implemented as a NUC (Next Unit of Computing) minicomputer.

[0062] Optionally, the hip joint, ankle joint, wheel joint, telescopic joint, pitch joint, and lateral joint of the quadrupedal wheel hybrid robot 200 can be driven independently by their respective drive motors.

[0063] In the technical solution provided in the embodiments of this application, the mechanical wheels, mechanical feet, mechanical legs, body (including IMU), and various joints (including 2 hip joints, 4 ankle joints, 4 wheel joints, 4 telescopic joints, 1 pitch joint and 1 lateral joint) of the quadrupedal wheel hybrid robot 200 are necessary hardware for the control algorithm, and the rest are non-essential hardware.

[0064] Compared to bipedal-wheeled hybrid robots, quadrupedal-wheeled hybrid robots have a more stable structure and stronger resistance to external impacts and disturbances. Compared to hexapedal-wheeled hybrid robots, they have fewer redundant joints, lower design complexity, and can bear heavy loads, move through narrow spaces, and perform tasks on objects of different heights. Quadrupedal-wheeled robots have a strong adaptability to the environment.

[0065] The robot control method provided in this application can be applied to any scenario that requires switching from foot support state to wheel support state, such as switching from gait walking task to gliding task, switching from four-wheel support state to four-legged support state or two-legged support state, or switching from two-wheel support state to four-legged support state or two-legged support state.

[0066] For example, refer to Figure 3In the quadrupedal support state, all four mechanical legs of the quadrupedal-wheel hybrid robot 300 are in contact with the support surface, allowing the robot to maintain its position on the support surface through the assistance of its four mechanical wheels 301. The angle between the first mechanical leg group 303 (composed of two outer mechanical legs) and the second mechanical leg group 304 (composed of two inner mechanical legs) is zero. When the quadrupedal-wheel hybrid robot 300 needs to perform wheeled tasks such as gliding, gait walking, straddling, or standing, it can switch from the quadrupedal support state to the four-wheel support state by coordinating the inner and outer mechanical legs and adjusting the ankle joints corresponding to the four mechanical legs 302. In the four-wheel support state, the quadrupedal-wheel hybrid robot 300 stands on the support surface only through its four mechanical wheels 301, while the four mechanical legs 302 are retracted and not in contact with the support surface. The 300 quadrupedal hybrid robot with four wheels is more suitable for performing wheeled tasks, which can refer to tasks that the robot completes in a wheeled support state.

[0067] This allows the robot to perform different tasks by switching states, improving its flexibility, adaptability to the environment, and versatility. Furthermore, in wheel-supported mode, the robot can glide quickly using its mechanical wheels, thereby increasing its motion efficiency.

[0068] The following will use method embodiments to describe the robot control method provided in the embodiments of this application. For content not described in the method embodiments, please refer to the above embodiments.

[0069] Please refer to Figure 4 This document illustrates a flowchart of a robot control method according to an embodiment of this application. In this embodiment, the robot control method is described using a robot as the executing entity for each step. The method may include the following steps (401-402):

[0070] Step 401: Stand on the support surface in a foot-supported state, wherein the robot stands by mechanical feet assisted by mechanical wheels in the foot-supported state.

[0071] In this embodiment, the robot's initial state is a foot-supported state, which refers to a state in which the robot maintains its upright position by using mechanical feet to assist the mechanical wheels. In the foot-supported state, the mechanical wheels and mechanical feet together provide support for the robot. The foot-supported state can be used to constrain the position and posture of various parts of the robot, so that the robot can maintain its upright position simultaneously through the mechanical wheels and mechanical feet, especially for the robot's mechanical wheels and mechanical feet.

[0072] For example, the foot-supported state can be used to constrain the robot's mechanical wheels and mechanical feet to contact the support surface, thereby providing support for the robot and enabling it to remain upright. Optionally, the foot-supported state can also be used to constrain at least one of the following: the robot's body remains vertical, and the included angle between the inner and outer mechanical legs is not zero or is zero; this application embodiment does not limit this.

[0073] Optionally, the robot can be determined to be in a foot-supported state if at least one mechanical foot assists the mechanical wheel to support the robot's standing. In one example, the foot-supported state includes at least one of the following: a quadrupedal support state and a bipedal support state. A quadrupedal support state refers to a state in which the robot is maintained standing by four mechanical feet assisting the mechanical wheel, while a bipedal support state refers to a state in which the robot is maintained standing by two mechanical feet assisting the mechanical wheel.

[0074] Taking a quadrupedal wheeled hybrid robot as an example, in quadrupedal support mode, the robot can stand on the support surface with the assistance of its four mechanical legs. The angle between the first and second mechanical leg groups can be zero, which is called the quadrupedal overlapping support mode. Alternatively, the angle between the first and second mechanical leg groups can be non-zero, which is called the quadrupedal non-overlapping support mode. Compared to the quadrupedal overlapping support mode, the robot can stand more stably in the quadrupedal non-overlapping support mode. In bipedal support mode, the robot can maintain its position by relying on the two mechanical legs corresponding to the first mechanical leg group or the two mechanical legs corresponding to the second mechanical leg group and their auxiliary wheels.

[0075] For example, refer to Figure 3 The quadrupedal wheel hybrid robot 300 stands on the support surface in a quadrupedal support state. In the quadrupedal support state, the quadrupedal wheel hybrid robot 300 uses four mechanical legs 302 to assist the four mechanical wheels 301 in maintaining its upright position. The body of the quadrupedal wheel hybrid robot 300 remains vertical, that is, the waist remains vertical. The two arms of the quadrupedal wheel hybrid robot 300 are bent and placed on both sides of the body. The angle between the first mechanical leg group 303 and the second mechanical leg group 304 of the quadrupedal wheel hybrid robot 300 is zero, and they are brought together to form a stable support for the quadrupedal wheel hybrid robot 300.

[0076] The robot in this embodiment is the same as that described in the above embodiments. Contents not described in this embodiment can be referred to in the above embodiments, and will not be repeated here. For ease of understanding, this embodiment uses a quadrupedal wheeled hybrid robot as an example.

[0077] The aforementioned support surface refers to the surface for robot movement, such as a surface used to support the robot's standing position. In the embodiments of this application, the support surface may consist of only one plane, such as a flat ground or road, or it may consist of multiple planes of different heights, such as stairs, a road surface with shoulders, or a ground with depressions. The embodiments of this application do not limit this.

[0078] In the embodiments of this application, the body can refer to the robot's waist (base) and the parts above the waist (such as the torso, head and upper limbs) forming a whole. For example, during the robot's movement, the robot's torso, head and upper limbs can be controlled to remain stationary so as to move as a whole with the robot's waist. That is, the rotation of the body can be controlled by controlling the pitch joint and yaw joint of the waist.

[0079] The robot's waist can serve as the base for its body, allowing the body to move based on the waist. With a stable waist, the body can also move stably. The body can be implemented as a fixed base or a mobile platform, achieving stability by keeping the robot's waist upright.

[0080] Alternatively, a vertical waist can mean that the central axis of the waist is parallel to the direction of gravity, that is, the upper surface of the waist (the surface closest to the torso) is horizontal, thus providing a stable platform for the robot and making it less likely to tip over during movement. For example, see reference. Figure 3 The quadrupedal wheeled hybrid robot 300 keeps its body upright (i.e., its waist is upright) so that it is not easy to tip over during movement.

[0081] Step 402: Move the mechanical foot away from the support surface, so that the robot changes from the foot-supported state to the wheel-supported state and stands on the support surface. In the wheel-supported state, the robot stands only on the mechanical wheels.

[0082] In this embodiment, the state the robot needs to transition to is a wheel-supported state, which refers to a state where the robot stands upright solely by relying on its mechanical wheels. The wheel-supported state can be used to constrain the position and posture of various parts of the robot, ensuring that the robot stands upright solely by its mechanical wheels, particularly its mechanical wheels and legs.

[0083] For example, the wheel-supported state can be used to constrain the robot's mechanical wheels to contact the support surface, thereby providing support for the robot to maintain its upright position, and to constrain the robot's mechanical feet from contacting the support surface. Optionally, the wheel-supported state can also be used to constrain at least one of the following: the robot's body remains vertical, and the angle between the inner and outer mechanical legs is not zero or is zero; this application embodiment does not limit this. Keeping the body vertical can mean keeping the central axis of the body parallel to the direction of gravity (i.e., the vertical direction).

[0084] In one example, the wheel support state includes at least one of the following: a four-wheel support state and a two-wheel support state. A four-wheel support state refers to a state in which the vehicle is supported by only four mechanical wheels, while a two-wheel support state refers to a state in which the vehicle is supported by only two mechanical wheels.

[0085] Taking a quadrupedal hybrid robot as an example, in a four-wheeled support state, the robot can stand on a support surface using its four mechanical legs. The angle between the first and second mechanical leg groups can be zero, referred to as the four-wheel overlapping support state. Alternatively, the angle between the first and second mechanical leg groups can be non-zero, referred to as the four-wheel non-overlapping support state. Compared to the four-wheel overlapping support state, the robot can stand more stably in the four-wheel non-overlapping support state. In a two-wheeled support state, the robot can maintain its position using only the two mechanical wheels corresponding to either the first or second mechanical leg group.

[0086] For example, refer to Figure 3 The quadrupedal wheel hybrid robot 300 stands on the support surface 303 in a four-wheel support state. In the four-wheel support state, the quadrupedal wheel hybrid robot 300 is supported only by the four mechanical wheels 301. The body of the quadrupedal wheel hybrid robot 300 remains vertical, that is, the waist remains vertical. The two arms of the quadrupedal wheel hybrid robot 300 are bent and placed on both sides of the body. The angle between the first mechanical leg group 303 and the second mechanical leg group 304 of the quadrupedal wheel hybrid robot 300 is not zero, and they are naturally spread apart to form a stable support for the quadrupedal wheel hybrid robot 300.

[0087] In one example, the process of enabling a robot to transition from a foot-supported state to a wheel-supported state while standing on a support surface can be simply referred to as a state transition task. A state transition task includes a preparation state, where the robot can first transition from a foot-supported state to a preparation state, and then from the preparation state to the wheel-supported state. The purpose of setting the preparation state is to adjust the robot to a suitable state for the state transition, so that the robot can stably transition from a foot-supported state to a wheel-supported state. For example, refer to... Figure 5 Step 402 can also include the following sub-steps.

[0088] Step 402a: By adjusting at least one of the joint angle of the hip joint and the extension / retraction amount of the robot's telescopic joint, the robot transitions from a foot-supported state to a ready state standing on the support surface. The hip joint is used to control the rotation of the robot's mechanical legs, and the telescopic joint is used to adjust the length of the robot's mechanical legs. In the ready state, the robot satisfies at least one of the following: the included angle between the first and second mechanical leg groups is zero, the extension / retraction amount of the telescopic joint is greater than the lower limit of the extension / retraction amount and less than the preset extension / retraction amount threshold, and the robot body is vertical.

[0089] The rotation of the hip joint can be controlled by adjusting its angle. This hip joint rotation drives the rotation of the robotic leg, thus allowing adjustment of the angle between the first and second robotic leg groups. The extension and retraction of the telescopic joint can be controlled by adjusting its range of motion, which affects the length of the robotic leg. The rotation of the robot body can be controlled via the pitch and yaw joints.

[0090] For example, by adjusting the joint angle of the hip joint, the angle between the first and second robotic leg groups is made zero. Adjusting the angle between the first and second robotic leg groups to zero allows one robotic leg group's corresponding robotic foot to provide auxiliary support during the process of controlling the robotic feet of the two robotic leg groups to lift off the ground one after the other, thereby maintaining the robot's stability.

[0091] By adjusting the extension and retraction of the telescopic joint, the extension and retraction amount is made greater than the lower limit of the extension and retraction amount but less than the preset threshold. The extension and retraction amount indicates the degree of extension of the telescopic joint. The lower limit indicates the minimum extension of the telescopic joint, at which point the mechanical leg is at its minimum length (i.e., the lower limit of length). The upper limit indicates the maximum extension of the telescopic joint, at which point the mechanical leg is at its maximum length (i.e., the upper limit of length).

[0092] This application embodiment does not limit the preset extension / retraction threshold, which can be set and adjusted according to actual usage needs. For example, the preset extension / retraction threshold can be set to a small value, that is, the joint angle of the telescopic joint can be adjusted to a small value, so that the robot's center of gravity is located at a lower height, which helps improve the robot's stability when performing state switching tasks. In addition, this application embodiment limits the extension / retraction amount of the robot's telescopic joint in the ready state to a lower limit value, so that the mechanical leg is at a suitable length, avoiding the problem that the mechanical leg cannot shorten further due to being at the lower length limit, thereby avoiding affecting the length adjustment of the mechanical leg. For example, the target extension / retraction amount that the telescopic joint in the ready state can be adjusted to includes at least one of the following: 4 cm, 5 cm, and 6 cm.

[0093] With the angle between the first and second robotic leg assemblies and the extension / retraction amount of the telescopic joints determined, the height of the fuselage is also determined. Optionally, the fuselage can be made vertical by adjusting the pitch and yaw joints.

[0094] In one example, based on the position and posture of each part of the robot in the foot-supported state, at least one of the following can be adaptively adjusted: the joint angle of the hip joint corresponding to the first mechanical leg group, the joint angle of the hip joint corresponding to the second mechanical leg group, the extension and retraction of the telescopic joint corresponding to the first mechanical leg group, the extension and retraction of the telescopic joint corresponding to the second mechanical leg group, the joint angle of the pitch joint, and the joint angle of the lateral joint, so that the robot transitions from the foot-supported state to the ready state standing on the support surface. Exemplarily, the process of transitioning from the foot-supported state to the ready state includes at least one of the following:

[0095] 1. Adjust at least one of the joint angles of the hip joints corresponding to the first mechanical leg group and the second mechanical leg group, so that the robot can transition from a foot-supported state to a ready state and stand on the support surface.

[0096] Optionally, the hip joint angle on the robotic leg is the target joint angle when the two robotic leg sets are together. In a quadrupedal support state, if the hip joint angle corresponding to one and only one robotic leg set is the target joint angle, then only the hip joint angle corresponding to the other robotic leg set needs to be adjusted to the target joint angle. If the hip joint angles corresponding to both robotic leg sets are not the target joint angles, then the hip joint angles corresponding to both robotic leg sets need to be adjusted to the target joint angles. If the hip joint angles corresponding to both robotic leg sets are the target joint angles, then the hip joint angles corresponding to both robotic leg sets do not need to be adjusted.

[0097] For example, refer to Figure 6 In the quadrupedal support state, if the extension and retraction of the telescopic joints on each mechanical leg of the quadrupedal wheel hybrid robot 300 is between the lower limit of the extension and retraction and the preset extension and retraction threshold, and the robot body is vertical, then it is only necessary to simultaneously adjust the joint angle of the hip joint corresponding to the first mechanical leg group 303 and the joint angle of the hip joint corresponding to the second mechanical leg group 304 to the target joint angle, so as to adjust the included angle between the first mechanical leg group 303 and the second mechanical leg group 304 to zero, so that the quadrupedal wheel hybrid robot 300 can switch from the foot support state to the ready state.

[0098] 2. Adjust at least one of the extension and retraction amounts of the telescopic joints corresponding to the first mechanical leg group and the second mechanical leg group, so that the robot can transition from a foot-supported state to a ready state and stand on the support surface.

[0099] Optionally, in a quadrupedal support state, if the extension / retraction amount of the telescopic joint corresponding to one and only one mechanical leg group is between the lower limit of the extension / retraction amount and the preset extension / retraction amount threshold, then only the extension / retraction amount of the telescopic joint corresponding to the other mechanical leg group needs to be adjusted to be between the lower limit of the extension / retraction amount and the preset extension / retraction amount threshold. If the extension / retraction amount of the telescopic joint corresponding to both mechanical leg groups is not between the lower limit of the extension / retraction amount and the preset extension / retraction amount threshold, then the extension / retraction amount of the telescopic joint corresponding to both mechanical leg groups needs to be adjusted to be between the lower limit of the extension / retraction amount and the preset extension / retraction amount threshold. If the extension / retraction amount of the telescopic joint corresponding to both mechanical leg groups is between the lower limit of the extension / retraction amount and the preset extension / retraction amount threshold, then the extension / retraction amount of the telescopic joint corresponding to both mechanical leg groups does not need to be adjusted.

[0100] For example, refer to Figure 6 In the quadrupedal support state, if the joint angle of the hip joint on each mechanical leg of the quadrupedal wheeled hybrid robot 300 is the target joint angle and the body is vertical, then it is only necessary to simultaneously adjust the extension and retraction of the telescopic joint corresponding to the first mechanical leg group 303 and the extension and retraction of the telescopic joint corresponding to the second mechanical leg group 304 to the target extension and retraction (e.g., 5 cm) to adjust the height of the body to the preset height, so that the quadrupedal wheeled hybrid robot 300 can switch from the foot support state to the ready state.

[0101] 3. By simultaneously adjusting the joint angle of the hip joint corresponding to the first mechanical leg group, the joint angle of the hip joint corresponding to the second mechanical leg group, the extension and retraction of the telescopic joint corresponding to the first mechanical leg group and the extension and retraction of the telescopic joint corresponding to the second mechanical leg group, the robot can transition from a foot-supported state to a ready state standing on the support surface.

[0102] For example, refer to Figure 6 In the quadrupedal support state, if the joint angles of the hip joints on each mechanical leg of the quadrupedal wheeled hybrid robot 300 are not the target joint angles, the extension and retraction of the telescopic joints on each mechanical leg are not the target extension and retraction, and the robot body is vertical, then the joint angles of the hip joints corresponding to the first mechanical leg group 303 and the second mechanical leg group 304 need to be adjusted to the target joint angles, and the extension and retraction of the telescopic joints corresponding to the first mechanical leg group 303 and the second mechanical leg group 304 need to be adjusted to the target extension and retraction, so that the quadrupedal wheeled hybrid robot 300 can switch from the foot support state to the ready state.

[0103] In the embodiments of this application, the robot's body remains vertical during the robot's movement, that is, the pitch joint and yaw joint are controlled not to rotate.

[0104] In one example, in the ready state, the robot can satisfy the following: the included angle between the first and second mechanical leg groups is zero; in the ready state, the robot can also satisfy the following: the extension and retraction of the telescopic joint is greater than the lower limit of the extension and retraction and less than the preset extension and retraction threshold; in the ready state, the robot can also satisfy the following: the included angle between the first and second mechanical leg groups is zero, and the extension and retraction of the robot's telescopic joint is greater than the lower limit of the extension and retraction and less than the preset extension and retraction threshold; in the ready state, the robot can also satisfy the following: the included angle between the first and second mechanical leg groups is zero, the extension and retraction of the robot's telescopic joint is greater than the lower limit of the extension and retraction and less than the preset extension and retraction threshold, and the robot body is vertical. This application embodiment does not limit these aspects.

[0105] In some embodiments, reference Figure 6 In the ready state, the angle between the first mechanical leg group 303 and the second mechanical leg group 304 is zero, and they are in a parallel position. The extension and retraction of the telescopic joint of the quadrupedal wheel hybrid robot 300 is greater than the lower limit of the extension and retraction and less than the preset extension and retraction threshold (e.g., the extension and retraction of the telescopic joint is 5 cm). The body of the quadrupedal wheel hybrid robot 300 is vertical.

[0106] Optionally, the length of each mechanical leg can be reduced by decreasing the extension and retraction of each telescopic joint of the quadrupedal wheel-driven hybrid robot 300. This allows the quadrupedal wheel-driven hybrid robot 300 to transition from a foot-supported state to a ready state standing on the support surface. Lowering the height of the quadrupedal wheel-driven hybrid robot 300's center of gravity improves its motion stability. The body of the quadrupedal wheel-driven hybrid robot 300 remains vertical. At this time, the center of gravity of the quadrupedal wheel-driven hybrid robot 300 falls within its support area, allowing it to stand stably. The aforementioned support area can be the area enclosed by the contact points between the quadrupedal wheel-driven hybrid robot 300 and the support surface (such as the contact points between each mechanical wheel 301 and each mechanical leg 302 and the support surface).

[0107] Step 402b: By adjusting the joint angle of the robot's ankle joint, the mechanical foot is moved away from the support surface, so that the robot changes from the ready state to the wheel-supported state and stands on the support surface. The ankle joint is used to control the rotation of the mechanical foot.

[0108] By adjusting the joint angle of the robot's ankle joint, the rotation of the ankle joint can be controlled. The rotation of the ankle joint can then drive the rotation of the mechanical foot, thus achieving the goal of controlling the rotation of the mechanical foot by adjusting the joint angle of the robot's ankle joint.

[0109] Optionally, if the robot has only one mechanical foot, the mechanical foot can be moved away from the support surface by adjusting the joint angle of the ankle joint on the mechanical foot, so that the robot can switch from the ready state to the wheel-supported state and stand on the support surface.

[0110] When a robot has multiple mechanical legs, by adjusting the joint angle of the ankle joint on some of the mechanical legs, that part of the mechanical leg is moved away from the support surface, so that the robot can switch from the ready state to the wheel-supported state and stand on the support surface.

[0111] In one example, the robot's body remains vertical while performing a state switching task; and the robot's height remains unchanged while performing a task from a ready state to a wheel-supported state.

[0112] In summary, the technical solution provided in this application provides a solution for a robot with an inner mechanical leg and an outer mechanical leg connected to the body via a hip joint. Since the hip joint corresponding to the inner mechanical leg is located between the hip joints corresponding to the two outer mechanical legs, and at least one mechanical leg has a pair of coaxial mechanical wheels and mechanical feet on its foot away from the hip joint, when the robot stands on the support surface with the assistance of the mechanical feet and mechanical wheels, the inner and outer mechanical legs can work together to move the mechanical feet coaxial with the mechanical wheels away from the support surface. This allows the robot to stand on the support surface solely by the mechanical wheels, thus entering a wheel-supported state. This enables the wheel-legged robot with mechanical feet to switch from a foot-supported state to a wheel-supported state, allowing the robot to perform different tasks by switching states, thereby improving the robot's flexibility.

[0113] In some embodiments, during the process of the robot performing a task to transition from a ready state to a wheel-supported state, multiple intermediate states can be set for the robot to guide the robot to transition stably from the ready state to the wheel-supported state.

[0114] Optionally, different intermediate states can be set for the robot depending on the distribution of the mechanical feet. For example, the distribution states of the mechanical feet include at least one of the following: mechanical feet are provided on at least one inner mechanical leg and at least one outer mechanical leg (i.e., mechanical feet are provided on both the first mechanical leg group and the second mechanical leg group); or only one mechanical leg group in the first mechanical leg group and the second mechanical leg group is provided with mechanical feet.

[0115] For example, when the robot has only one mechanical leg, the mechanical leg can be located on the inner mechanical leg or the outer mechanical leg. When the robot has multiple mechanical legs, some mechanical legs can be located on the inner mechanical leg and others can be located on the outer mechanical leg. The maximum number of mechanical legs corresponding to the first mechanical leg group is 2, but this application embodiment does not limit this.

[0116] For example, refer to Figure 3 The first mechanical leg group 303 and the second mechanical leg group 304 of the quadrupedal wheeled hybrid robot 300 are both provided with mechanical feet. Optionally, mechanical feet may be provided only for the first mechanical leg group 303 of the quadrupedal wheeled hybrid robot 300, or only for the second mechanical leg group 304 of the quadrupedal wheeled hybrid robot 300. This application embodiment does not limit this.

[0117] Optionally, in the foot-supported state, all of the robot's mechanical feet are in contact with the support surface.

[0118] In one example, if mechanical feet are provided on at least one inner mechanical leg and at least one outer mechanical leg, step 402b above may also include the following.

[0119] 1. Control the robot to transition from the ready state to the first state of standing on the support surface. In the first state, the projection point of the robot's center of mass on the support surface along the vertical direction falls within the projection area of ​​the mechanical foot corresponding to the auxiliary mechanical leg group on the support surface. The joint angle of the ankle joint of the main mechanical leg group is rotated to the first joint angle. The first joint angle is used to ensure that the mechanical foot does not contact the support surface during the robot's movement.

[0120] The purpose of setting the first state is to adjust the joint angle of the ankle joint of the main mechanical leg assembly to a suitable joint angle so that the mechanical foot of the main mechanical leg assembly can be removed from the support surface, thus enabling the main mechanical leg assembly to switch from the foot support state to the wheel support state.

[0121] Optionally, when mechanical feet are provided on at least one inner mechanical leg and at least one outer mechanical leg, that is, when both the first and second mechanical leg groups are provided with mechanical feet, one mechanical leg group is the main mechanical leg group and the other is the auxiliary mechanical leg group. When the first mechanical leg group is the main mechanical leg group, the second mechanical leg group is the auxiliary mechanical leg group; when the second mechanical leg group is the main mechanical leg group, the first mechanical leg group is the auxiliary mechanical leg group.

[0122] For example, refer to Figure 7In the ready state, the first mechanical leg group 303 can be used as the main mechanical leg group and the second mechanical leg group 304 can be used as the auxiliary mechanical leg group, or the first mechanical leg group 303 can be used as the auxiliary mechanical leg group and the second mechanical leg group 304 can be used as the main mechanical leg group.

[0123] In the first state, the ankle joint angle of the main robotic leg assembly is rotated to a first joint angle, ensuring that the robotic foot of the main robotic leg assembly does not contact the support surface. This first joint angle can be set empirically; it can be any joint angle that prevents the robotic foot of the main robotic leg assembly from contacting the support surface during the robot's movement. For example, a joint angle close to the lower limit of the ankle joint angle can be set as the first joint angle. The lower limit of the ankle joint angle can refer to the joint angle at which the robotic foot can be raised to its highest height, and the upper limit of the ankle joint angle can refer to the joint angle at which the robotic foot can move to its lowest height.

[0124] In one example, when the mechanical wheel corresponding to the main mechanical leg assembly has an active state and a locked state, the joint angle that puts the mechanical wheel in the active state can be defined as the first joint angle, so that the mechanical wheel corresponding to the main mechanical leg assembly can roll. Specifically, in the active state, the mechanical wheel can rotate; in the locked state, the mechanical wheel cannot rotate. When the ankle joint of the mechanical wheel rotates to less than a certain angle, the mechanical wheel switches from the locked state to the active state. For example, for a quadrupedal wheel-and-machine hybrid robot, the mechanical wheel on its inner mechanical leg can be set to an active state and a locked state, while the mechanical wheel on its outer mechanical leg does not have an active state and a locked state (e.g., it can always rotate). This active state and locked state can be implemented through a special structure, which is not limited in this embodiment.

[0125] Optionally, when the mechanical wheel corresponding to the main mechanical leg assembly is set to an active state and a locked state, rotating the joint angle of the ankle joint of the main mechanical leg assembly to the first joint angle can make the mechanical wheel of the main mechanical leg assembly active, thereby allowing the mechanical wheel of the main mechanical leg assembly to move in a rolling manner.

[0126] Optionally, after the main robotic leg assembly's mechanical feet detach from the support surface, the robot's center of mass, projected vertically onto the support surface, automatically falls within the projection area of ​​the corresponding mechanical foot of the auxiliary robotic leg assembly on the support surface. The robot's center of gravity is the point where its weight is concentrated; the robot's center of mass is the weighted average of the mass's position. If gravity is uniform, the center of mass and center of gravity can coincide. In this embodiment, the robot's center of mass is located on its waist, such as at the center point of the waist. This can be achieved by controlling the projection of the center point of the waist vertically onto the support surface, ensuring it falls within the projection area of ​​the corresponding mechanical foot of the main robotic leg assembly on the support surface.

[0127] For example, after the main robotic leg assembly's mechanical foot detaches from the support surface, the robot tilts slightly toward the direction of the corresponding mechanical foot of the auxiliary robotic leg assembly, so that the robot's center of mass, projected vertically onto the support surface, falls within the projection area of ​​the corresponding mechanical foot of the auxiliary robotic leg assembly onto the support surface.

[0128] In one feasible example, the projection of the center point of the waist onto the support surface in the vertical direction can be controlled to fall at a target distance in front of the mechanical wheels corresponding to the auxiliary mechanical leg assembly, so that the projection of the robot's center of mass onto the support surface in the vertical direction falls at the center of the projection area of ​​the mechanical foot corresponding to the main mechanical leg assembly on the support surface. This target position can be determined based on the size of the mechanical foot, such as using half the length of the mechanical foot to determine the target distance, such as 4 cm, 5 cm, 6 cm, etc., which is not limited in this embodiment. The position of the waist can be adjusted based on both the hip joint and the telescopic joint.

[0129] The robot's center of mass is projected vertically onto the support surface and then positioned within the projection area of ​​the corresponding mechanical foot of the auxiliary mechanical leg assembly on the support surface. This allows the main mechanical leg assembly to switch to wheel-supported mode while the auxiliary mechanical leg assembly enables the robot to maintain stable standing and allows the robot to maintain stability during subsequent movements.

[0130] In one example, the ankle joints of the main robotic leg assembly can be rotated only in the direction close to the body to control the robot to transition from a ready state to a first state of standing on the support surface.

[0131] For example, rotating the ankle joint of the main mechanical leg assembly in a direction close to the body can rotate the joint angle of the ankle joint of the main mechanical leg assembly to a first joint angle, so that the mechanical foot of the main mechanical leg assembly is disengaged from the support surface and raised to a designated position.

[0132] Optionally, during the process of controlling the robot to transition from the ready state to the first state, the robot's body height can remain unchanged, and the body can remain vertical.

[0133] For example, refer to Figure 7 Taking the quadrupedal wheeled hybrid robot 300 in the ready state as an example, the ankle joint (i.e. the main mechanical leg group) of the first mechanical leg group 303 is rotated counterclockwise to adjust the joint angle of the ankle joint of the first mechanical leg group 303 to the first joint angle, thereby controlling the height of the quadrupedal wheeled hybrid robot 300 to remain unchanged and controlling the body of the quadrupedal wheeled hybrid robot 300 to remain vertical, so that the quadrupedal wheeled hybrid robot 300 transitions from the ready state to the first state.

[0134] In the first state, the projection point of the center of mass of the quadrupedal wheeled hybrid robot 300 onto the support surface in the vertical direction falls within the projection area of ​​the mechanical feet of the second mechanical leg assembly 304 onto the support surface. The friction between the mechanical feet 302 and mechanical wheels 301 of the second mechanical leg assembly 304 and the support surface allows the quadrupedal wheeled hybrid robot 300 to remain stable in the forward direction.

[0135] In one feasible example, the ready state can be merged into the first state. That is, while controlling the robot to transition from the foot support state to the ready state, the ankle joints of the main mechanical leg assembly are rotated only in the direction close to the body, so as to control the robot to directly transition from the ready state to the first state of standing on the support surface.

[0136] 2. Control the robot to transition from the first state to the second state and stand on the support surface. In the second state, the angle between the main mechanical leg group and the auxiliary mechanical leg group is greater than zero and less than a preset angle threshold. The projection point of the robot's center of mass on the support surface along the vertical direction falls within the robot's support area. The support area refers to the area enclosed by the contact points between the robot and the support surface.

[0137] The purpose of setting the second state is to adjust the projection point of the robot's center of mass onto the support surface in the vertical direction so that it falls within the robot's support area. This releases the mechanical feet of the auxiliary mechanical leg assembly, allowing the robot to rotate the mechanical feet of the auxiliary mechanical leg assembly away from the support surface while maintaining a stable standing position, which helps improve the robot's motion stability.

[0138] The aforementioned preset angle threshold can be set and adjusted according to actual usage requirements, and this application embodiment does not limit this. Adjusting the included angle between the first and second mechanical leg groups to be greater than zero and less than the preset angle threshold allows the first and second mechanical leg groups to naturally spread out, thus forming a triangular support for the robot body, which helps improve the robot's motion stability and makes it less prone to tipping over.

[0139] In this embodiment, the robot's center of mass is located on the robot's waist, such as at the center point of the waist. The projection point of the center point of the waist onto the support surface in the vertical direction can be controlled to fall within the robot's support area, thereby controlling the projection point of the robot's center of mass onto the support surface in the vertical direction to fall within the robot's support area.

[0140] For example, the projection point of the center point of the waist on the support surface in the vertical direction can be controlled to fall between the mechanical wheel corresponding to the main mechanical leg group and the mechanical wheel corresponding to the auxiliary mechanical leg group, such as the middle position between the mechanical wheel corresponding to the main mechanical leg group and the mechanical wheel corresponding to the auxiliary mechanical leg group, so that the projection point of the robot's center of mass on the support surface in the vertical direction falls on the center of the robot's support area, and so that the robot's center of mass is located between the two mechanical leg groups, thereby ensuring the stability of the robot.

[0141] In one example, while keeping the contact point between the mechanical wheel of the auxiliary mechanical leg group and the support surface unchanged, the hip joint of the main mechanical leg group can be rotated in the direction of the robot's movement, and the hip joint of the auxiliary mechanical leg group can be rotated in the opposite direction of the direction of movement, so as to control the robot to transition from the first state to the second state of standing on the support surface.

[0142] Optionally, the hip joints of the main robotic leg assembly can be rotated in the robot's forward direction, and the hip joints of the auxiliary robotic leg assembly can be rotated in the opposite direction. The ankle and wheel joints of the auxiliary robotic leg assembly can be adjusted accordingly to keep the contact points between the robotic feet and wheels of the auxiliary robotic leg assembly and the support surface unchanged. Rotating the hip joints of the main robotic leg assembly in the robot's forward direction and the hip joints of the auxiliary robotic leg assembly in the opposite direction adjusts the angle between the main and auxiliary robotic leg assemblies to between zero and a preset angle threshold. Furthermore, the adjustment of each hip joint allows the robot body to move in the forward direction, thereby adjusting the projection point of the robot's center of mass onto the support surface in the vertical direction to fall within the robot's support area.

[0143] Rotating the hip joint of the main robotic leg assembly in the robot's forward direction moves the main robotic leg assembly's mechanical wheels to a position a preset value away from the auxiliary robotic leg assembly's mechanical wheels. This preset value can include at least one of the following: 50 cm, 55 cm, 60 cm, or 70 cm. This embodiment does not limit the preset value. The robot body can be moved to a position half the preset value away from the auxiliary robotic leg assembly's mechanical wheels, so that the robot's center of mass, projected vertically onto the support surface, falls at the center of the robot's support area.

[0144] In one example, when the mechanical wheel corresponding to the auxiliary mechanical leg assembly is set to an active state and a locked state, since the mechanical foot corresponding to the auxiliary mechanical leg assembly is always parallel to the support surface, and the joint angle of its corresponding ankle joint can lock the mechanical wheel corresponding to the auxiliary mechanical leg assembly (i.e., the mechanical wheel is controlled in the locked state), the auxiliary mechanical leg assembly can still maintain the contact point between the mechanical wheel and the support surface through the friction between the mechanical foot and the mechanical wheel and the support surface respectively.

[0145] Optionally, during the transition from the first state to the second state, the robot's height and vertical position can be maintained. While keeping the robot's height constant, the lengths of the auxiliary and main robotic legs can be adaptively adjusted via telescopic joints.

[0146] For example, refer to Figure 8 Taking the quadrupedal wheeled hybrid robot 300 in its first state as an example, while keeping the contact point between the mechanical wheel corresponding to the second mechanical leg group 304 (i.e., the auxiliary mechanical leg group) and the supporting surface unchanged, the hip joint corresponding to the first mechanical leg group 303 (i.e., the main mechanical leg group) is rotated in the forward direction (while keeping the first joint angle unchanged) to adjust the distance between the contact point between the first mechanical leg group 303 and the supporting surface, and between the contact point between the second mechanical leg group 303 and the supporting surface, to a preset value (e.g., 60 cm), so that the included angle between the first mechanical leg group 303 and the second mechanical leg group 304 is adjusted to be greater than zero and less than a preset angle threshold. At the same time, the hip joint corresponding to the second mechanical leg group 304 is rotated in the opposite direction of the forward direction, so that the projection point of the center of mass of the quadrupedal wheeled hybrid robot 300 on the supporting surface in the vertical direction falls within the supporting area of ​​the quadrupedal wheeled hybrid robot 300.

[0147] The length of each mechanical leg is adaptively adjusted to keep the body height of the quadrupedal wheeled hybrid robot 300 constant and the body vertical, so that the quadrupedal wheeled hybrid robot 300 can transition from the first state to the second state.

[0148] 3. Control the robot to switch from the second state to the wheel-supported state and stand on the support surface. In the wheel-supported state, the mechanical feet corresponding to the auxiliary mechanical leg group are rotated to detach from the support surface, so that the mechanical wheels corresponding to the auxiliary mechanical leg group and the mechanical wheels corresponding to the main mechanical leg group form a support for the robot.

[0149] In the second state, the mechanical foot corresponding to the auxiliary robotic leg assembly is not yet off the ground. The mechanical foot can be moved off the ground by adjusting the ankle joint of the auxiliary robotic leg assembly. For example, the ankle joint of the auxiliary robotic leg assembly can be rotated only in the direction closer to the robot body to control the robot to switch from the second state to the wheel-supported state and stand on the support surface.

[0150] Specifically, by rotating the ankle joint of the auxiliary robotic leg assembly in a direction close to the robot body, the corresponding robotic foot of the auxiliary robotic leg assembly can be moved off the ground. Optionally, by rotating the ankle joint of the auxiliary robotic leg assembly in a direction away from the robot body, the joint angle of the ankle joint of the auxiliary robotic leg assembly can be rotated to the first joint angle, so that the corresponding robotic foot of the auxiliary robotic leg assembly does not come into contact with the supporting surface during the robot's subsequent movements.

[0151] Optionally, when the mechanical wheels corresponding to the auxiliary mechanical leg assembly are set to an active state and a locked state, if the joint angle of the ankle joint of the auxiliary mechanical leg assembly is rotated to the first joint angle, the mechanical wheels corresponding to the auxiliary mechanical leg assembly can switch to the active state, thereby enabling the mechanical wheels corresponding to the auxiliary mechanical leg assembly to support wheel-like motion.

[0152] For example, refer to Figure 9 Taking the quadrupedal wheel-supported hybrid robot 300 in the second state as an example, only the ankle joint of the second mechanical leg group 304 (i.e., the auxiliary mechanical leg group) is rotated counterclockwise to adjust the joint angle of the ankle joint of the second mechanical leg group 304 to the first joint angle, so that the mechanical foot of the second mechanical leg group 304 is removed from the support surface, thereby allowing the quadrupedal wheel-supported hybrid robot 300 to switch from the second state to the wheel-supported state.

[0153] Alternatively, the rest of the quadrupedal wheeled hybrid robot 300 remains unchanged.

[0154] In this embodiment, where mechanical feet are provided on both the inner and outer mechanical legs, the main mechanical leg assembly is first switched to a wheel-supported state, and then the auxiliary mechanical leg assembly is switched to a wheel-supported state. Since the auxiliary mechanical leg assembly can provide stable support for the robot after the main mechanical leg assembly is switched to the wheel-supported state, and the robot's center of mass falls within the robot's support area during the process of switching the auxiliary mechanical leg assembly to the wheel-supported state, and the included angle between the main and auxiliary mechanical leg assemblies is not zero, stability can be provided for the auxiliary mechanical leg assembly to switch to the wheel-supported state. This enables the robot to stably switch from the ready state to the wheel-supported state, which is beneficial to improving the stability of the robot in performing state switching tasks.

[0155] In one example, if only one of the first and second mechanical leg groups is equipped with a mechanical foot, step 402b above may also include the following.

[0156] 1. Control the robot to transition from the ready state to the first state and stand on the support surface. In the first state, the angle between the target mechanical leg group and the non-target mechanical leg group is greater than zero and less than a preset angle threshold. The projection point of the robot's center of mass on the support surface along the vertical direction falls within the robot's support area. The support area refers to the area enclosed by the contact points between the robot and the support surface.

[0157] In this embodiment, the purpose of setting the first state is to adjust the projection point of the robot's center of mass on the support surface in the vertical direction so that it falls within the robot's support area, thereby releasing the mechanical feet of the non-mechanical leg group. This allows the robot to rotate the mechanical feet of the non-mechanical leg group away from the support surface while maintaining a stable standing position, which is beneficial to improving the robot's motion stability.

[0158] Optionally, if only one of the first and second mechanical leg groups has a mechanical foot, the mechanical leg group with a mechanical foot is the target mechanical leg group, and the mechanical leg group without a mechanical foot is the non-target mechanical leg group.

[0159] For example, if the first robotic leg group has robotic feet while the second robotic leg group does not, the first robotic leg group can be designated as the target robotic leg group, and the second robotic leg group as a non-target robotic leg group. Similarly, if the second robotic leg group has robotic feet while the first robotic leg group does not, the second robotic leg group can be designated as the target robotic leg group, and the first robotic leg group as a non-target robotic leg group.

[0160] The aforementioned preset angle threshold can be set and adjusted according to actual usage requirements, and this application embodiment does not limit this. Adjusting the included angle between the first and second mechanical leg groups to be greater than zero and less than the preset angle threshold allows the first and second mechanical leg groups to naturally spread out, thus forming a triangular support for the robot body, which helps improve the robot's motion stability and makes it less prone to tipping over.

[0161] Optionally, the projection of the robot's center of mass onto the support surface in the vertical direction can be controlled to fall within the robot's support area. For example, the projection of the center of the waist onto the support surface can be controlled to fall between the mechanical wheel corresponding to the target mechanical leg group and the mechanical wheel corresponding to the non-target mechanical leg group, such as the midpoint between them. This ensures that the projection of the robot's center of mass onto the support surface in the vertical direction falls at the center of the robot's support area, and that the robot's center of mass is located between the two mechanical leg groups, thereby ensuring the robot's stability.

[0162] In one example, while keeping the contact point between the mechanical wheel corresponding to the target mechanical leg group and the support surface unchanged, the hip joint of the non-target mechanical leg group can be rotated in the direction of the robot's movement, and the hip joint of the target mechanical leg group can be rotated in the opposite direction of the direction of movement, so as to control the robot to transition from the ready state to the first state of standing on the support surface.

[0163] Optionally, the hip joints of the non-target mechanical leg group can be rotated in the robot's forward direction, and the hip joints of the target mechanical leg group can be rotated in the opposite direction, with corresponding adjustments to the ankle and wheel joints of the target mechanical leg group, so that the contact points between the mechanical feet and wheels of the target mechanical leg group and the support surface remain unchanged. Rotating the hip joints of the non-target mechanical leg group in the robot's forward direction and the hip joints of the target mechanical leg group in the opposite direction adjusts the angle between the target and non-target mechanical leg groups to between zero and a preset angle threshold. Furthermore, the adjustment of each hip joint allows the robot body to move in the forward direction, thereby adjusting the projection point of the robot's center of mass onto the support surface in the vertical direction to fall within the robot's support area.

[0164] Rotating the hip joint of the non-target robotic leg assembly in the robot's forward direction moves the mechanical wheels of the non-target robotic leg assembly to a position a preset value away from the mechanical wheels of the target robotic leg assembly. This preset value may include at least one of the following: 50 cm, 55 cm, 60 cm, or 70 cm. This embodiment of the application does not limit the preset value. The robot body can be moved to a position half the preset value away from the mechanical wheels of the target robotic leg assembly, so that the projection of the robot's center of mass onto the support surface in the vertical direction falls on the center of the robot's support area.

[0165] In one example, when the mechanical wheel corresponding to the target mechanical leg assembly is set to an active state and a locked state, since the mechanical foot corresponding to the target mechanical leg assembly is always parallel to the support surface, and the joint angle of its corresponding ankle joint can lock the mechanical wheel corresponding to the target mechanical leg assembly (i.e., the mechanical wheel is controlled in the locked state), the target mechanical leg assembly can still control the contact point between the mechanical wheel and the support surface to remain unchanged through the friction between the mechanical foot and the mechanical wheel and the support surface respectively.

[0166] Optionally, during the transition from the first state to the second state, the robot's height and vertical position can be maintained. While keeping the robot's height constant, the lengths of the target and non-target mechanical leg groups can be adaptively adjusted via telescopic joints.

[0167] For example, refer to Figure 8When the second mechanical leg group 304 is the target mechanical leg group (i.e., has mechanical feet) and the first mechanical leg group 303 is a non-target mechanical leg group (i.e., does not have mechanical feet), while keeping the contact point between the mechanical wheel corresponding to the second mechanical leg group 304 and the support surface unchanged, the hip joint corresponding to the first mechanical leg group 303 is rotated in the forward direction to adjust the distance between the contact point between the first mechanical leg group 303 and the support surface and the contact point between the second mechanical leg group 304 and the support surface to a preset value (e.g., 60 cm), so that the included angle between the first mechanical leg group 303 and the second mechanical leg group 304 is adjusted to be greater than zero and less than a preset angle threshold. At the same time, the hip joint corresponding to the second mechanical leg group 304 is rotated in the opposite direction of the forward direction, so that the projection point of the center of mass of the quadrupedal wheeled hybrid robot 300 on the support surface in the vertical direction falls within the support area of ​​the quadrupedal wheeled hybrid robot 300.

[0168] The length of each mechanical leg is adaptively adjusted to keep the body height of the quadrupedal wheeled hybrid robot 300 constant and the body vertical, so that the quadrupedal wheeled hybrid robot 300 can transition from the ready state to the first state of standing on the support surface.

[0169] For details not described in the embodiments of this application, please refer to the above embodiments, and they will not be repeated here.

[0170] 2. Control the robot to switch from the first state to the wheel-supported state and stand on the support surface. In the wheel-supported state, the mechanical feet corresponding to the target mechanical leg group are rotated to detach from the support surface, so that the mechanical wheels corresponding to the target mechanical leg group and the mechanical wheels corresponding to the non-target mechanical leg group form support for the robot.

[0171] In the first state, the mechanical foot corresponding to the target mechanical leg assembly has not yet left the ground. The mechanical foot can be moved to leave the ground by adjusting the ankle joint of the target mechanical leg assembly. For example, the ankle joint of the target mechanical leg assembly can be rotated only in the direction closer to the robot body to control the robot to switch from the first state to the wheel-supported state and stand on the support surface.

[0172] Specifically, by rotating the ankle joint of the target mechanical leg assembly in a direction close to the robot body, the corresponding mechanical foot of the target mechanical leg assembly can be moved off the ground. Optionally, by rotating the ankle joint of the target mechanical leg assembly in a direction away from the robot body, the joint angle of the ankle joint of the target mechanical leg assembly can be rotated to a first joint angle, so that the corresponding mechanical foot of the target mechanical leg assembly does not come into contact with the supporting surface during the robot's subsequent movements.

[0173] Optionally, if the mechanical wheel corresponding to the target mechanical leg assembly is configured with an active state and a locked state, and the joint angle of the ankle joint of the target mechanical leg assembly is rotated to the first joint angle, the mechanical wheel corresponding to the target mechanical leg assembly can be switched to the active state, thereby enabling the mechanical wheel corresponding to the target mechanical leg assembly to support wheel-like motion.

[0174] For example, refer to Figure 9 When the second mechanical leg group 304 is the target mechanical leg group (i.e., has mechanical feet) and the first mechanical leg group 303 is the non-target mechanical leg group (i.e., does not have mechanical feet), it is only necessary to rotate the ankle joint of the second mechanical leg group 304 counterclockwise to adjust the joint angle of the ankle joint of the second mechanical leg group 304 to the first joint angle, so that the mechanical feet of the second mechanical leg group 304 are removed from the support surface. After the mechanical feet of the second mechanical leg group 304 are moved to the point of being removed from the support surface, the mechanical wheels corresponding to the second mechanical leg group 304 and the mechanical wheels corresponding to the first mechanical leg group 303 form a support for the quadrupedal wheel-wheel hybrid robot 300, so that the quadrupedal wheel-wheel hybrid robot 300 changes from the first state to the wheel support state.

[0175] Alternatively, the rest of the quadrupedal wheeled hybrid robot 300 remains unchanged.

[0176] In this embodiment of the application, when only one of the first and second mechanical leg groups is equipped with a mechanical foot, after adjusting the robot's center of mass to fall within the robot's support area, adjusting the angle between the target mechanical leg group and the non-target mechanical leg group to be non-zero, and keeping the non-target mechanical leg group in a foot-supported state, the mechanical foot of the target mechanical leg group is then adjusted to leave the ground. This provides stability for the target mechanical leg group to switch to a wheel-supported state, thereby enabling the robot to stably transition from a ready state to a wheel-supported state, which is beneficial to improving the stability of the robot in performing state switching tasks.

[0177] In a feasible example, when only some of the mechanical legs are in contact with the support surface in the foot-supported state, the technical solution provided in the above embodiments can be adopted according to the distribution of the partial mechanical legs to enable the robot to switch from the ready state to the wheel-supported state. When the robot has only one mechanical leg, a scheme can be used to first adjust the robot to a stable state using the non-target mechanical leg group, and then adjust the mechanical leg of the target mechanical leg group, thereby ensuring the stability of the robot when performing state switching tasks.

[0178] In one example, after the robot transitions from a foot-supported state to a wheel-supported state and stands on the support surface, the length of the mechanical leg can be adjusted by the telescopic joints on the mechanical leg, and the angle between the inner and outer mechanical legs can be adjusted by the hip joints on the mechanical leg to lower the height of the robot's center of gravity. This allows the robot to transition from a wheel-supported state to a wheeled motion state and stand on the support surface. In the wheeled motion state, the robot performs tasks by standing on the support surface solely through the mechanical wheels.

[0179] Wheeled motion state can refer to the state used to perform wheeled motion. For example, refer to... Figure 10 The length of the first mechanical leg assembly 303 is adjusted by the telescopic joints corresponding to the first mechanical leg assembly 303, the length of the second mechanical leg assembly 304 is adjusted by the telescopic joints corresponding to the second mechanical leg assembly 304, and the angle between the first and second mechanical leg assemblies 303 and 304 is adjusted by the hip joints corresponding to the first and second mechanical leg assemblies 303 and 304, respectively. This lowers the height of the center of gravity of the quadrupedal wheeled hybrid robot 300, allowing it to transition from a wheeled support state to a wheeled movement state while standing on the support surface. In the wheeled movement state, the quadrupedal wheeled hybrid robot 300 is more suitable for performing wheeled tasks such as gliding, gait walking, and object carrying.

[0180] The embodiments of this application make the robot more suitable for wheeled motion by lowering the height of the robot's center of gravity.

[0181] In some embodiments, reference Figure 11 Taking the quadrupedal wheeled hybrid robot 1100 as an example, the technical solutions provided in the embodiments of this application will be described. The embodiments of this application may also include the following contents.

[0182] Phase 1: Controlling the robot to transition from a quadrupedal support state to the first state.

[0183] First mechanical leg assembly 1101 (outer mechanical leg): Keep the contact point between the first mechanical leg assembly 1101 and the support surface unchanged; adjust the extension and retraction of the corresponding telescopic joint of the first mechanical leg assembly 1101 to 5 cm to reduce the length of the outer mechanical leg; rotate the ankle joint of the first mechanical leg assembly 1101 counterclockwise to adjust the joint angle of the ankle joint of the first mechanical leg assembly 1101 to the first joint angle, so that the mechanical foot of the first mechanical leg assembly 1101 is adjusted to detach from the support surface (the projection point of the center of mass of the quadrupedal wheel hybrid robot 1100 along the vertical direction on the support surface automatically falls within the projection area of ​​the mechanical foot of the second mechanical leg assembly 1102 on the support surface).

[0184] Second mechanical leg assembly 1102 (inner mechanical leg): Keep the contact point between the second mechanical leg assembly 1102 and the support surface unchanged; adjust the extension and retraction of the corresponding telescopic joint of the second mechanical leg assembly 1102 to 5 cm to reduce the length of the inner mechanical leg.

[0185] Body 1103: Remains vertical; under the influence of each telescopic joint, the height of body 1103 is reduced (i.e., the height of the center of mass of the quadrupedal wheeled hybrid robot 1100 is reduced).

[0186] Phase Two: Controlling the robot to transition from the first state to the second state.

[0187] First mechanical leg assembly 1101 (outer mechanical leg): Rotate the first mechanical leg assembly 1101 counterclockwise so that the contact point between the first mechanical leg assembly 1101 and the support surface moves to a position 60 cm in front of the contact point between the second mechanical leg assembly 1102 and the support surface; adjust the length of the first mechanical leg assembly 1101 accordingly.

[0188] Second mechanical leg assembly 1102 (inner mechanical leg): Keep the contact point between the mechanical wheel corresponding to the second mechanical leg assembly 1102 and the support surface unchanged; rotate the second mechanical leg assembly 1102 clockwise so that the angle between the second mechanical leg assembly 1102 and the first mechanical leg assembly 1101 is adjusted to between zero and a preset angle threshold; adjust the length of the second mechanical leg assembly 1102 accordingly.

[0189] Body 1103: remains vertical; under the action of each hip joint and each telescopic joint, body 1103 (such as the waist center) moves to a position 30 cm in front of the contact point between the second mechanical leg group 1102 and the support surface, so that the center of mass of the quadrupedal wheel hybrid robot 1100 falls on the center of the support area of ​​the quadrupedal wheel hybrid robot 1100; under the action of each hip joint and each telescopic joint, the height of body 1103 remains unchanged.

[0190] Phase 3: Controlling the robot to transition from the second state to the four-wheel support state.

[0191] First mechanical leg group 1101 (outer mechanical leg): Keep stationary.

[0192] Second mechanical leg assembly 1102 (inner mechanical leg): Only the ankle joint of the second mechanical leg assembly 1102 is rotated counterclockwise to adjust the joint angle of the ankle joint of the second mechanical leg assembly 1102 to the first joint angle, so that the mechanical foot of the second mechanical leg assembly 1102 is adjusted to be detached from the support surface.

[0193] Fuselage 1103: Remain stationary.

[0194] In summary, the technical solution provided in this application provides a solution for a robot with an inner mechanical leg and an outer mechanical leg connected to the body via a hip joint. Since the hip joint corresponding to the inner mechanical leg is located between the hip joints corresponding to the two outer mechanical legs, and at least one mechanical leg has a pair of coaxial mechanical wheels and mechanical feet on its foot away from the hip joint, when the robot stands on the support surface with the assistance of the mechanical feet and mechanical wheels, the inner and outer mechanical legs can work together to move the mechanical feet coaxial with the mechanical wheels away from the support surface. This allows the robot to stand on the support surface solely by the mechanical wheels, thus entering a wheel-supported state. This enables the wheel-legged robot with mechanical feet to switch from a foot-supported state to a wheel-supported state, allowing the robot to perform different tasks by switching states, thereby improving the robot's flexibility.

[0195] In some embodiments, after determining the various states (such as the preparation state, the first state, and the second state) involved in controlling the robot to switch from a foot-supported state to a wheel-supported state (i.e., the state switching task described above), reference movement trajectories for each part of the robot can be planned according to each state to obtain a set of reference movement trajectories for the robot, and then the robot can be controlled to switch from a foot-supported state to a wheel-supported state based on the set of reference movement trajectories.

[0196] For example, the robot's reference movement trajectory set includes at least one of the following: a reference movement trajectory of the body, a reference movement trajectory of the mechanical legs, a reference movement trajectory of the mechanical wheels, and a posture reference change trajectory of the body. The reference movement trajectory of the mechanical legs may include the reference movement trajectories of the mechanical legs in the first mechanical leg group and the reference movement trajectories of the mechanical legs in the second mechanical leg group. The reference movement trajectory of the mechanical wheels may include the reference movement trajectories of the mechanical wheels in the first mechanical leg group and the reference movement trajectories of the mechanical wheels in the second mechanical leg group.

[0197] The reference movement trajectory includes reference positions at multiple control moments required for the robot to transition from a foot-supported state to a wheel-supported state. These reference positions refer to the planned positions. Control moments refer to the times when the robot is controlled via control signals. These control moments are arranged at specified time intervals, which can be set and adjusted according to actual usage requirements. For example, a specified time interval of 0.002 seconds means that a control signal is sent to the robot every 0.002 seconds to control its movement. This application does not limit the number of these multiple control moments; they can be set and adjusted according to actual usage requirements.

[0198] This application embodiment allows for the selection of one or more reference movement trajectories to control the robot's transition from a foot-supported state to a wheel-supported state, based on task requirements. For example, the robot's transition from a foot-supported state to a wheel-supported state can be controlled based on the reference movement trajectory of the robot body, the reference movement trajectory of the mechanical feet, the reference movement trajectory of the mechanical wheels, and the posture change trajectory of the robot body.

[0199] The process of obtaining each reference movement trajectory will be explained below.

[0200] Reference movement trajectory of the mechanical wheel:

[0201] The reference trajectory of the mechanical wheels is used to guide the movement of the entire robotic leg assembly (including the mechanical wheels, mechanical legs, and mechanical feet). For example, the reference trajectory of the mechanical wheels includes the reference position of the mechanical wheels at various control moments to guide the robotic leg assembly to move according to the reference trajectory of the mechanical wheels.

[0202] The reference trajectory of the mechanical wheel is planned based on the trajectory of the mechanical wheel's movement on the support surface. Optionally, the reference trajectory in this embodiment can be obtained using a spline curve interpolation method. For example, the reference trajectory of the mechanical wheel can be obtained by interpolating the position of the mechanical wheel in each of the above states using a spline curve interpolation method. The position of the mechanical wheel in each state can be planned based on the dimensions of the support surface, the dimensions of the robot, and the position required for the task.

[0203] Optionally, each mechanical wheel corresponds to a reference movement trajectory. When the mechanical legs in the same mechanical leg group move synchronously, each mechanical leg group can correspond to a reference movement trajectory of one mechanical wheel.

[0204] For example, refer to Figure 11 Taking a quadrupedal wheel-driven hybrid robot 1100 as an example, for each mechanical wheel of the quadrupedal wheel-driven hybrid robot 1100, for the first stage, spline curve interpolation can be used to interpolate the position of the mechanical wheel in the quadrupedal support state with the position of the mechanical wheel in the first state to obtain the reference movement trajectory of the mechanical wheel in the first stage. For the second stage, spline curve interpolation can be used to interpolate the position of the mechanical wheel in the first state with the position of the mechanical wheel in the second state to obtain the reference movement trajectory of the mechanical wheel in the second stage. For the third stage, spline curve interpolation can be used to interpolate the position of the mechanical wheel in the second state with the position of the mechanical wheel in the quadrupedal support state to obtain the reference movement trajectory of the mechanical wheel in the third stage. By combining the reference movement trajectories of the mechanical wheel in the first stage to the reference movement trajectories of the mechanical wheel in the third stage, the reference movement trajectory of the mechanical wheel can be obtained.

[0205] Optionally, the position of the mechanical wheel can be characterized by the position of the center point of the mechanical wheel, or by the position of the contact point between the mechanical wheel and the support surface. This application does not limit this.

[0206] For example, the first mechanical leg assembly 1101 can be controlled to move by the reference movement trajectory of the mechanical wheels in the first mechanical leg assembly 1101. For example, the reference movement trajectory of the mechanical wheels in the first mechanical leg assembly 1101 can guide the contact point between the first mechanical leg assembly 1101 and the support surface to first remain stationary, then move to the right, and then remain stationary again.

[0207] The second mechanical leg assembly 1102 can be controlled to move by the reference movement trajectory of the mechanical wheels in the second mechanical leg assembly 1102. For example, the reference movement trajectory of the mechanical wheels in the second mechanical leg assembly 1102 can guide the contact point between the second mechanical leg assembly 1102 and the support surface to remain stationary.

[0208] Reference movement trajectory of the mechanical foot:

[0209] The reference movement trajectory of the mechanical foot is used to guide its movement. For example, the reference movement trajectory of the mechanical foot includes the reference position of the mechanical foot at each control moment to guide the mechanical foot to move according to the reference movement trajectory. Optionally, each mechanical foot corresponds to a separate reference movement trajectory; or, each mechanical leg group corresponds to a separate reference movement trajectory of a mechanical foot, which is not limited in this embodiment.

[0210] The reference movement trajectory of the mechanical foot can be obtained by planning the movement trajectory of the mechanical foot based on the support surface. For example, a spline curve interpolation method can be used to interpolate the position of the mechanical foot in each of the above states to obtain the reference movement trajectory of the mechanical foot. The position of the mechanical foot can be represented by the position of the center point of the mechanical foot, or it can be represented by the position of the toe of the mechanical foot. This application embodiment does not limit this.

[0211] For example, refer to Figure 11Taking a quadrupedal wheeled hybrid robot 1100 as an example, for each mechanical leg of the quadrupedal wheeled hybrid robot 1100, for the first stage, spline curve interpolation can be used to interpolate the position of the mechanical leg in the quadrupedal support state with the position of the mechanical leg in the first state to obtain the reference movement trajectory of the mechanical leg in the first stage. For the second stage, spline curve interpolation can be used to interpolate the position of the mechanical leg in the first state with the position of the mechanical leg in the second state to obtain the reference movement trajectory of the mechanical leg in the second stage. For the third stage, spline curve interpolation can be used to interpolate the position of the mechanical leg in the second state with the position of the mechanical leg in the quadrupedal support state to obtain the reference movement trajectory of the mechanical leg in the third stage. By combining the reference movement trajectories of the mechanical leg in the first stage to the reference movement trajectories of the mechanical leg in the third stage, the reference movement trajectory of the mechanical leg can be obtained.

[0212] For example, the mechanical foot corresponding to the first mechanical leg group 1101 can be controlled to move by the reference movement trajectory of the mechanical foot in the first mechanical leg group 1101. For example, the reference movement trajectory of the mechanical foot in the first mechanical leg group 1101 can guide the mechanical foot in the first mechanical leg group 1101 to rotate counterclockwise first, and then keep it from rotating.

[0213] The mechanical foot corresponding to the second mechanical leg assembly 1102 can be controlled to move by the reference movement trajectory of the mechanical foot in the second mechanical leg assembly 1102. For example, the reference movement trajectory of the mechanical foot in the second mechanical leg assembly 1102 can guide the mechanical foot in the second mechanical leg assembly 1102 to first remain stationary and then rotate counterclockwise.

[0214] Reference movement trajectory of the fuselage:

[0215] A reference movement trajectory for the robot body is used to guide its movement. For example, the reference movement trajectory includes the reference position of the robot body at various control moments to guide its movement along the trajectory. In this embodiment, the position of the robot body can be represented by the position of the waist, such as the center point of the waist. In this embodiment, the position of the waist can refer to the position of the robot's center of mass.

[0216] The reference movement trajectory of the fuselage is planned based on the movement trajectory of the fuselage from the support surface. For example, the reference movement trajectory of the fuselage can be obtained by interpolating the position of the fuselage in each of the above states using spline curve interpolation.

[0217] For example, refer to Figure 11Taking the quadrupedal wheeled hybrid robot 1100 as an example, for the first stage, spline curve interpolation can be used to interpolate the position of the robot body in the quadrupedal support state with its position in the first state to obtain the reference movement trajectory of the robot body in the first stage. For the second stage, spline curve interpolation can be used to interpolate the position of the robot body in the first state with its position in the second state to obtain the reference movement trajectory of the robot body in the second stage. For the third stage, spline curve interpolation can be used to interpolate the position of the robot body in the second state with its position in the quadrupedal support state to obtain the reference movement trajectory of the robot body in the third stage. By sequentially combining the reference movement trajectories of the robot body from the first stage to the third stage, the final reference movement trajectory of the robot body can be obtained.

[0218] For example, the fuselage 1103 can be controlled to move by a reference movement trajectory of the fuselage 1103. For example, the reference movement trajectory of the fuselage 1103 can be used to guide the fuselage 1103 to move downward first, and then maintain the same height.

[0219] In one example, the reference movement trajectory of the chassis is used to control the robot's center of mass to be located within the robot's support area, which is the area enclosed by the contact points between the robot and the support surface. For example, the reference movement trajectory of chassis 1103 can be used to control the center of mass of the quadrupedal-wheeled hybrid robot 1100 to fall within its support area, so that the quadrupedal-wheeled hybrid robot 1100 can stably transition from a quadrupedal support state to a four-wheeled support state.

[0220] Aircraft attitude reference change trajectory:

[0221] The robot's attitude reference trajectory refers to the reference trajectory of the robot's waist attitude, which can be used to describe the attitude changes of the robot's waist. The attitude reference trajectory includes the reference attitude of the waist at each control moment. Optionally, the robot's attitude can be represented by the attitude of the waist.

[0222] The aforementioned waist posture can be represented using Euler angles, such as Euler angles composed of roll, pitch, and yaw of the waist. The aforementioned posture reference change trajectory can refer to the Euler angle reference movement trajectory corresponding to the waist of the robot. This Euler angle reference movement trajectory includes the reference Euler angles (i.e., reference posture) at each control moment.

[0223] Optionally, when the reference posture is represented by the Euler angles of the waist, the Euler angles of the waist are always zero. That is, during the process of the robot changing from a foot-supported state to a wheel-supported state, the waist always remains vertical (i.e., the body always remains vertical), which helps to reduce the control complexity of the robot.

[0224] For example, refer to Figure 11 For example, the attitude reference change trajectory of the waist of the quadrupedal wheeled hybrid robot 1100 can be determined as the attitude reference change trajectory of the body 1103. The attitude reference change trajectory of the body 1103 can be used to guide the body 1103 to always remain vertical.

[0225] In some embodiments, after obtaining the robot's reference movement trajectory set, the robot's dynamics can be used to control the robot to transition from a foot-supported state to a wheel-supported state while standing on a support surface. For example, based on the reference movement trajectories of various parts of the robot, the desired acceleration of each part is determined, and the robot's joints are controlled based on this desired acceleration to enable the robot to transition from a foot-supported state to a wheel-supported state while standing on a support surface. Therefore, embodiments of this application may further include the following:

[0226] 1. For any control moment corresponding to the robot, based on the robot's reference movement trajectory set, obtain the robot's first expected task at the control moment. The first expected task includes the expected acceleration of each part of the robot in the robot's operating space. The first expected task is used to control the robot to switch from a foot-supported state to a wheel-supported state and stand on the support surface.

[0227] In this embodiment, the expected task refers to the task that the robot is expected to perform in the operating space, such as the task set for each part of the robot according to the aforementioned state switching task. This expected task can be a task concerning the position, velocity, and acceleration of each part of the robot. For example, the aforementioned first expected task can refer to a task set for the acceleration of each part of the robot. This first expected task can be planned based on the robot and its actual environment. For example, based on the dimensions of the support surface, the dimensions of each part of the robot, and the structure of the robot, the expected acceleration of each part of the robot can be planned to obtain the first expected task corresponding to the scenario. Wherein, the expected acceleration of each part is the expected acceleration of that part, and the expected acceleration of a certain part can be used to indicate the acceleration that part is expected to achieve. This expected acceleration refers to the acceleration used to actually control the robot, rather than a reference value.

[0228] Optionally, the first desired task corresponds to the complete process of the robot transitioning from a foot-supported state to a wheel-supported state, i.e., including the aforementioned multiple stages (such as multiple state transition processes). If the complete process corresponds to multiple control moments, the first desired task may include the desired acceleration of each part of the robot under the multiple controls. For example, under the constraints of the robot's dynamics, the first desired task of the robot at the control moment can be obtained based on a reference motion trajectory set.

[0229] The robot can control the movement of various parts of the robot through the expected accelerations in the first expected task, so that the robot can switch from a foot-supported state to a wheel-supported state. For example, the robot can control the robot's mechanical leg assembly (such as mechanical legs, mechanical feet, and mechanical wheels) and body (such as waist, torso, head, and mechanical arm) through the expected accelerations in the first expected task, so that the robot can switch from a foot-supported state to a wheel-supported state.

[0230] The robot can control its movement by following reference movement trajectories of various parts to transition from a foot-supported state to a wheel-supported state, based on the desired acceleration of each part. For example, the first desired task may include at least one of the following: desired foot acceleration of the mechanical foot, desired wheel acceleration of the mechanical wheel, desired leg acceleration of the mechanical leg, desired body acceleration of the robot body, and desired angular acceleration of the robot body.

[0231] For example, the expected acceleration of the foot can be used to control the mechanical foot to rotate, the expected acceleration of the wheel can be used to control the mechanical wheel to roll, and the expected acceleration of the leg can be used to control the mechanical leg to rotate, the expected acceleration of the body can be used to control the body to move, and the expected angular acceleration of the body can be used to control the body to rotate.

[0232] This application embodiment allows for the selection of one or more desired accelerations to control the robot's transition from a foot-supported state to a wheel-supported state, based on task requirements. For example, the robot's transition from a foot-supported state to a wheel-supported state can be controlled based on desired foot acceleration, desired wheel acceleration, desired fuselage acceleration, and desired fuselage angular acceleration.

[0233] The aforementioned robot's operating space can refer to the Cartesian space corresponding to the robot. In task-oriented whole-body control, the Cartesian space corresponding to the robot can be called the robot's operating space. In the embodiments of this application, each position in the robot's operating space can be represented based on the robot's world coordinate system.

[0234] For example, a world coordinate system for the robot can be constructed with the contact point between the robot's foot (e.g., the mechanical wheel) and the supporting surface in its initial state (such as the foot-supported state described above) as the origin, the horizontal direction as the x-axis, the vertical direction as the z-axis, and the direction perpendicular to both the horizontal and vertical directions as the y-axis. The robot's position in the operating space can be characterized based on its three-dimensional coordinates in the world coordinate system. Optionally, the calculation processes in the embodiments of this application all occur in the robot's world coordinate system.

[0235] Optionally, the desired acceleration included in the first desired task can be calculated by a feedback controller based on the reference movement trajectory of each part of the robot and the actual state of the robot, such as a PD (Proportion-Differentiation) feedback controller, or other feedback controllers.

[0236] In one example, the first expected task mentioned above includes the expected acceleration of the fuselage, and the process of obtaining the expected acceleration of the fuselage may include the following:

[0237] (1) Based on the reference movement trajectory of the fuselage, obtain the reference position, reference speed and reference acceleration of the fuselage at the control moment.

[0238] Based on the control timing, the corresponding reference position can be determined from the robot's reference trajectory. Then, the reference velocity and reference acceleration can be obtained based on the reference position. For example, the first derivative of the reference position with respect to time can be determined as the reference velocity, and the second derivative of the reference position with respect to time can be determined as the reference acceleration. Note that the reference acceleration differs from the desired acceleration; it is a planned value and is not directly used to control the robot.

[0239] Optionally, the reference velocity and reference acceleration of the fuselage can both be set to zero.

[0240] (2) Using a PD feedback controller, the desired acceleration of the fuselage at the control moment is calculated based on the reference position, reference speed and reference acceleration of the fuselage at the control moment, as well as the actual position and actual speed of the fuselage at the control moment.

[0241] Optionally, based on the IMU on the robot body, the acceleration, angular velocity, and attitude (i.e., actual Euler angles) of the robot body can be measured. Combined with the actual angles and accelerations of all the robot's joints, as well as the contact points between the robot and the support surface, a state estimation algorithm can be used to obtain the actual position, actual velocity, actual attitude, and actual angular velocity of the robot body in the world coordinate system. Furthermore, given the relative position, relative velocity, and relative angular velocity between the hip joint's center point and the IMU, the state of the hip joint's center point can be calculated based on the robot body's state (i.e., the actual position, actual velocity, actual attitude, and actual angular velocity of the robot body in the world coordinate system).

[0242] In this embodiment, the center point of the hip joint is the origin of the robot's floating base coordinate system. Based on the state of the hip joint center point, the state of the floating base coordinate system can be obtained. Combined with the actual angles and angular velocities of all robot joints, and using the forward kinematics model of the robot's full model, the actual positions, velocities, attitudes, and angular velocities of all corresponding links in the world coordinate system can be calculated. These links include the waist, thus allowing the calculation of the actual position and velocity of the waist in the operating space. Here, the actual position refers to the true position of the robot body, and the actual velocity refers to the true velocity of the robot body, also a true value. Variations of the forward kinematics model can be used to indicate the relationship between the robot's acceleration in the operating space and its velocity and acceleration in the robot's joint space.

[0243] For example, the desired acceleration of the fuselage can be expressed as follows:

[0244]

[0245] in, Let be the desired fuselage acceleration at control time t. and These represent the reference acceleration, reference velocity, and reference position of the fuselage in the operating space at control time t. and These represent the actual position and actual velocity of the fuselage in the operating space at control time t, respectively, and k. p，base and k d，base These correspond to the proportional and differential coefficients for the robot's body position, respectively. By calculating the desired acceleration of the robot body using the PD feedback controller, the robustness of the robot's controller can be improved.

[0246] In one example, the first desired task mentioned above includes the desired angular acceleration of the fuselage, and the process of obtaining the desired angular acceleration of the fuselage may include the following:

[0247] (1) Based on the attitude reference change trajectory of the fuselage, obtain the reference attitude, reference attitude velocity and reference attitude acceleration of the fuselage at the control moment.

[0248] The corresponding reference attitude can be determined from the attitude reference change trajectory of the fuselage according to the control time. Then, the reference attitude velocity and reference attitude acceleration can be obtained based on the reference attitude. For example, the first derivative of the reference attitude with respect to time can be determined as the reference attitude velocity, and the second derivative of the reference attitude with respect to time can be determined as the reference attitude acceleration.

[0249] For example, if the reference attitude is represented by the Euler angles at the waist when the fuselage is always vertical, then the Euler angles at the waist are always zero, that is, the reference attitude, the reference attitude velocity, and the reference attitude acceleration are all always zero.

[0250] For example, the reference attitude, reference attitude velocity, and reference attitude acceleration of the fuselage at the moment of control can be expressed as follows:

[0251] and

[0252] (2) Using a PD feedback controller, the desired angular acceleration of the fuselage at the control moment is calculated based on the reference attitude acceleration, reference attitude velocity and reference attitude of the fuselage at the control moment, as well as the actual attitude and actual attitude velocity of the fuselage at the control moment.

[0253] Optionally, based on the IMU information on the waist, the actual attitude (i.e., actual Euler angles) and actual attitude velocity (i.e., actual Euler angular velocity) of the fuselage can be calculated.

[0254] For example, the desired angular acceleration of the fuselage can be expressed as follows:

[0255]

[0256] in, Let be the desired angular acceleration of the fuselage at control time t. and These represent the reference attitude, reference attitude velocity, and reference attitude acceleration of the fuselage in the operating space at control time t, respectively. and These represent the actual attitude and actual attitude velocity of the fuselage in the operating space at control time t, respectively, and k. p，euler and k d，euler These correspond to the proportional coefficient and differential coefficient for the fuselage attitude, respectively.

[0257] In one example, the first desired task described above may further include the desired acceleration of each mechanical wheel. For each mechanical wheel, the process of obtaining the desired wheel acceleration may include the following:

[0258] (1) Based on the reference movement trajectory of the mechanical wheel, obtain the reference position, reference velocity and reference acceleration of the mechanical wheel at the control moment.

[0259] Based on the control time, the corresponding reference position can be determined from the reference movement trajectory of the mechanical wheel, and then the reference velocity and reference acceleration can be obtained based on the reference position. For example, the first derivative of the reference position with respect to time can be determined as the reference velocity, and the second derivative of the reference position with respect to time can be determined as the reference acceleration.

[0260] Optionally, the reference speed and reference acceleration of the mechanical wheel at each control moment can both be set to zero.

[0261] Optionally, in this embodiment of the application, it is desired that the mechanical wheel and the supporting surface undergo pure rolling motion without relative sliding motion. Therefore, the desired acceleration of the mechanical wheel relative to the supporting surface is always zero, denoted as... Where, N C This represents the number of contact forces corresponding to the robot, which is the product of the number of contact points and the dimension of a single contact force. A contact point refers to the point where the robot comes into contact with the support surface, such as the mechanical wheel and the support surface having one contact point.

[0262] (2) Using a PD feedback controller, the desired acceleration of the mechanical wheel at the control moment is calculated based on the reference position, reference speed and reference acceleration of the mechanical wheel at the control moment, as well as the actual position and actual speed of the mechanical wheel at the control moment.

[0263] Optionally, based on the IMU on the robot, the actual joint angles and actual joint angular accelerations of all joints of the robot can be measured. Then, by combining the contact points between the robot and the support surface and using a state estimation algorithm (or forward kinematics), the actual position and actual velocity of the mechanical wheel in the world coordinate system can be obtained.

[0264] For example, the desired acceleration of a wheel can be expressed as follows:

[0265]

[0266] in, Let be the desired acceleration of the wheel at control time t. and These represent the reference acceleration, reference velocity, and reference position of the mechanical wheel in the operating space at control time t. and These represent the actual position and actual speed of the mechanical wheel in the operating space at control time t, respectively, and k. p，wheel and k d，wheel These correspond to the proportional coefficient and differential coefficient for the position of the mechanical wheel, respectively.

[0267] In one example, the first expected task mentioned above may also include the expected foot acceleration of each mechanical foot. Then, for each mechanical foot, the process of obtaining the expected foot acceleration may include the following:

[0268] (1) Based on the reference movement trajectory of the mechanical foot, obtain the reference position, reference velocity and reference acceleration of the mechanical foot at the control moment.

[0269] Based on the control time, the corresponding reference position can be determined from the reference movement trajectory of the mechanical foot, and then the reference velocity and reference acceleration can be obtained based on the reference position. For example, the first derivative of the reference position with respect to time can be determined as the reference velocity, and the second derivative of the reference position with respect to time can be determined as the reference acceleration.

[0270] Optionally, the reference velocity and reference acceleration of the mechanical foot at each control moment can both be set to zero.

[0271] (2) Using a PD feedback controller, the expected acceleration of the mechanical foot at the control time is calculated based on the reference position, reference velocity and reference acceleration of the mechanical foot at the control time, as well as the actual position and actual velocity of the mechanical foot at the control time.

[0272] Optionally, based on the IMU on the robot body, the joint acceleration, joint angular velocity, and actual posture (i.e., actual Euler angles) of the robot body can be measured. Then, combined with the actual joint angles, actual joint angular accelerations of all joints of the robot, and the contact points between the robot and the support surface, the actual position and actual posture of the robot body and the robotic leg in the world coordinate system can be obtained using a state estimation algorithm. Then, based on the rotation angle and joint angular velocity of the ankle joint, the actual position and actual velocity of the robotic foot at the control moment can be determined. Among them, the actual position and actual velocity of the toe of the robotic foot at the control moment can be determined as the actual position and actual velocity of the robotic foot at the control moment.

[0273] For example, the desired acceleration can be expressed as follows:

[0274]

[0275] in, To achieve the desired acceleration at control time t, and These represent the reference acceleration, reference velocity, and reference position of the mechanical foot in the operating space at control time t. and These represent the actual position and actual velocity of the mechanical foot in the operating space at control time t, respectively, and k. p，foot and k d，foot These correspond to the proportional coefficient and differential coefficient for the position of the mechanical foot, respectively.

[0276] For example, the robot's first desired task at control time t can be represented as follows:

[0277]

[0278] in, This includes the expected acceleration of each mechanical wheel of the robot. This includes the expected acceleration of each mechanical wheel of the robot. This includes the desired acceleration of each of the robot's mechanical wheels relative to the support surface.

[0279] 2. Obtain the first expected torque set corresponding to the first expected task. The first expected torque set includes the first expected torques used to control each joint of the robot.

[0280] Optionally, each desired acceleration in the first desired task can be converted into a corresponding desired torque, which can then be used to control the movement of each joint, enabling the robot to transition from a foot-supported state to a wheel-supported state while standing on the support surface. For example, the aforementioned first desired torque set includes at least one of the following: first desired torques corresponding to the hip joint, ankle joint, wheel joint, telescoping joint, pitch joint, and lateral joint, respectively. These first desired torques can be used to control the joints to rotate or telescop.

[0281] In one example, the aforementioned first desired task can be used for the robot's task-oriented whole body control, that is, taking into account the dynamic information such as the mass and inertia of all the robot's links, mobilizing all the robot's degrees of freedom, and controlling the robot to complete one or more set tasks.

[0282] For example, based on the rigid body dynamics of a robot, the whole-body dynamics model of a robot in the joint space frame can be represented as follows:

[0283]

[0284] in, This represents the joint space inertia matrix of the robot. This represents the joint space offset force vector of the robot, which is the sum of the Coriolis force, centrifugal force, and gravity force corresponding to the robot. Represents the robot's selection matrix. The Jacobian matrix represents the contact points between the robot and the support surface. This represents the torque vector of the robot's joints. This represents the contact force vector of the robot. N represents the generalized position vector, generalized velocity vector, and generalized acceleration vector at each degree of freedom of the robot. G The total degrees of freedom of the robot, i.e., the floating basis degrees of freedom N. F With joint degrees of freedom N J sum, N C n represents the number of contact forces corresponding to the robot, i.e., the number of contact points. C Dimension N of a single contact force D The product of ∈{0,1,2,3}.

[0285] by Figure 3 Taking a quadrupedal wheeled hybrid robot as an example, the linkage of the quadrupedal wheeled hybrid robot 300 may include four mechanical legs, four mechanical wheels, four mechanical feet, and a body (waist, torso, upper limbs, and head as a whole). The joints of the quadrupedal wheeled hybrid robot 300 may include two hip joints (the two inner mechanical legs share one hip joint, and the two outer mechanical legs share one iliac canal joint), extension joints corresponding to the four mechanical legs, wheel joints of the four mechanical wheels, ankle joints of the four mechanical feet, and one pitch joint and one lateral joint corresponding to the body. Optionally, the robot's joint degrees of freedom are the degrees of freedom corresponding to the aforementioned 16 joints.

[0286] The floating base degrees of freedom refer to the six degrees of freedom of the robot's floating base coordinate system in the world coordinate system: position (px-py-pz) and posture (yaw-roll-pitch). The floating base coordinate system is constructed with the rotation center of the hip joint as the origin, and the coordinate axes of the floating base coordinate system are initially aligned with the world coordinate system. The number of contact points can refer to the number of contact points between the robotic legs (including robotic wheels and robotic feet) and the supporting surface. For example, when the robot stands on the supporting surface using two sets of robotic legs, the number of contact points is at least four (each robotic leg corresponds to at least two contact points).

[0287] The aforementioned whole-body kinematics model can refer to a variation of the robot's positive kinematics model, which is used to indicate the relationship between the robot's acceleration in the operating space and the robot's velocity and acceleration in the robot's joint space.

[0288] Alternatively, as can be seen from rigid body dynamics, a variation of this forward kinematic model can be expressed as follows:

[0289]

[0290] in, This represents the robot's acceleration in the operand space at control time t. and Let J represent the robot's velocity and acceleration in joint space, i.e., the generalized position vector and generalized velocity vector at each degree of freedom of the robot. t and Let represent the Jacobian matrix and the first derivative of the Jacobian matrix corresponding to the state switching task t (i.e., the task space).

[0291] For example, the process of obtaining the first desired torque set of the robot at each control moment may include the following:

[0292] (1) Based on the whole-body dynamics model and the whole-body kinematics model, the dynamic equation to be solved is constructed, with the acceleration of the robot in the joint space as the unknown variable.

[0293] For example, by simultaneously solving the whole-body dynamics model and the whole-body kinematics model, the simplified dynamic equation to be solved can be expressed as follows:

[0294]

[0295] in, One is an unknown variable, and the rest are known variables.

[0296] The above describes the process of constructing the dynamic equation to be solved. These are preset steps and only need to be constructed once before the calculation of the first desired torque set. The first desired torque set at each subsequent control time can be obtained by applying the dynamic equation to be solved.

[0297] (2) Substitute the first expected task into the dynamic equation to be solved, and calculate the first expected torque set.

[0298] Optionally, during the robot's movement, it is also subject to physical constraints imposed by the robot's body structure and drive motors. To improve the rationality and accuracy of the first desired torque set, this application further sets constraints during the solution process of the first desired torque set. For example, the solution process of the dynamic equation to be solved can be as follows:

[0299] By replacing the robot's acceleration in the operating space in the dynamic equations to be solved with the first desired task, we obtain the intermediate dynamic equations.

[0300] Optionally, the above The acceleration of the robot in the operating space in the dynamic equations to be solved By making substitutions, the intermediate dynamic equations can be obtained.

[0301] Construct the joint physical constraint expression and friction constraint expression of the robot. The joint physical constraint expression is used to constrain each joint of the robot. The contact force between the robot and the support surface under the constraint of the friction constraint expression satisfies the friction cone constraint.

[0302] Optionally, based on the actual physical characteristics of the robot's drive motor, the joint torque τ in the unknown variables is limited, i.e., the joint physical constraint expression can be: τ lb ≤τ≤τ ub ; where τ lb and τ ub These represent the minimum and maximum torque values ​​of the joint motor, respectively.

[0303] Optionally, the contact force between the foot of the robotic leg and the supporting surface should satisfy the friction cone constraint. To reduce nonlinearity, the friction cone can be approximated as a friction angle cone, and the friction constraint expression can be:

[0304]

[0305] Where, n x n y and n z Let μ represent the unit orthogonal basis of the contact surface at the lower edge of the world coordinate system. i f represents the coefficient of friction corresponding to the i-th contact force. i Let f represent the i-th contact force. z，lb and f z，ub These represent the minimum and maximum values ​​of the non-negative positive pressure perpendicular to the contact surface, respectively. Each foot corresponds to a contact force, which can be the combined force of the mechanical wheel and the mechanical foot (e.g., the mechanical foot assisting the mechanical wheel in standing), or it can be the contact force corresponding to the mechanical wheel alone (e.g., wheel-like motion). This application does not limit this specific force.

[0306] Under the constraints of the robot's joint physical constraints and friction constraints, the first desired torque set is calculated based on the intermediate dynamic equations.

[0307] Alternatively, the intermediate dynamic equations can be rewritten in the form AX = B;

[0308] in,

[0309] The process of solving AX = B is essentially about finding the solution to a system of linear equations. Therefore, a quadratic programming optimization method can be used here to construct the objective function of the intermediate dynamic equations.

[0310] Alternatively, the objective function of the intermediate dynamic equation can be expressed as follows:

[0311] J = min(AX - B) T Q(AX-B)+X T RX;

[0312] Where Q and R represent weight matrices.

[0313] Under the constraints of the robot's joint physical constraints and friction constraints, the first desired torque set is obtained by minimizing the objective function. For example, using a quadratic programming optimizer, under the constraints of the robot's joint physical constraints and friction constraints, the unknown variable X can be obtained by minimizing the objective function. The joint torque τ in the unknown variable X can be directly determined as the first desired torque set, denoted as...

[0314] by Figure 3 Taking the quadrupedal wheel-driven hybrid robot 300 as an example, the first desired torque set may include two hip joints (each hip joint corresponds to a mechanical leg group), four telescopic joints of mechanical legs, four wheel joints of mechanical wheels, four ankle joints of mechanical feet, and one pitch joint and one lateral joint corresponding to the first desired torque.

[0315] Alternatively, if the robot's model structure is relatively simple, then the robot's whole-body dynamics model and whole-body kinematics model are also relatively simple. In this case, the intermediate dynamic equations can be solved directly using the method of finding the pseudo-inverse of the matrix, i.e., X = A. -1 B, to obtain the first desired torque set.

[0316] 3. Based on the first expected torque set, move the mechanical foot away from the support surface, so that the robot changes from a foot-supported state to a wheel-supported state and stands on the support surface.

[0317] For any given control moment, the first desired torque set includes the first desired torque of each joint of the robot, which is used to control the rotation of the joints. At any given control moment, by simply driving the joint motors corresponding to each joint according to the first desired torque of each joint at that control moment, the first desired task can be achieved, that is, moving the mechanical foot away from the support surface, so that the robot can switch from a foot-supported state to a wheel-supported state and stand on the support surface.

[0318] In summary, the technical solution provided in this application, by employing the robot's whole-body dynamics model and whole-body kinematics model, can accurately obtain the first expected moment set corresponding to the robot's reference movement trajectory set based on the robot's reference movement trajectory set. Furthermore, based on the first expected moment set, the robot can be accurately controlled to transition from a foot-supported state to a wheel-supported state while standing on the support surface, thereby improving the robot's control accuracy.

[0319] Furthermore, by solving the intermediate dynamic equations under the constraints of the robot's joint physical constraints and friction constraints, a reasonable and accurate first expected moment set can be obtained, which can further improve the robot's control accuracy.

[0320] In some embodiments, after obtaining the robot's reference movement trajectory set, the robot's kinematics can also be used to control the robot to perform tasks. For example, based on the reference movement trajectories of various parts of the robot, the desired joint angles of each part of the robot are determined, and the robot's joints are controlled based on the desired joint angles to enable the robot to perform tasks. Therefore, embodiments of this application may further include the following:

[0321] 1. For any control moment corresponding to the robot, based on the robot's reference movement trajectory set, obtain the robot's second expected task at the control moment. The second expected task includes the reference positions of various parts of the robot in the robot's operating space. The second expected task is used to control the robot to switch from a foot-supported state to a wheel-supported state and stand on the support surface.

[0322] The aforementioned second expected task can refer to a task set for the position of various parts of the robot. This second expected task can be planned based on the robot and its actual environment. For example, based on the dimensions of the supporting surface, the dimensions of each part of the robot, and the structure of the robot, the expected positions of each part of the robot can be planned to obtain the second expected task corresponding to the scenario. The planned position of each part is its reference position. The reference position of a part can be used to indicate the planned position of that part; this reference position is the planned value.

[0323] Optionally, the second desired task also corresponds to the complete process of the robot transitioning from a foot-supported state to a wheel-supported state, i.e., including the aforementioned multiple stages (such as multiple state transition processes). If the complete process corresponds to multiple control moments, the second desired task may include the reference positions of various parts of the robot under the multiple controls respectively.

[0324] The robot can control the movement of various parts of the robot through the reference positions in the second expected task mentioned above, so that the robot can switch from a foot-supported state to a wheel-supported state and stand on the support surface. For example, the robot can control the robot's mechanical leg assembly (such as mechanical legs, mechanical feet, and mechanical wheels) and body (such as waist, torso, head, and mechanical arm) through the reference positions in the second expected task mentioned above, so that the robot can switch from a foot-supported state to a wheel-supported state and stand on the support surface.

[0325] The robot can be controlled to move by following the reference movement trajectory of each part through the reference position of each part. For example, the second desired task may include at least one of the following: the reference position of the mechanical foot, the reference position of the mechanical wheel, the reference position of the mechanical leg, the reference position of the body, and the reference posture of the body.

[0326] For example, the reference position of the mechanical foot can be used to guide the mechanical foot to rotate, the reference position of the mechanical wheel can be used to guide the mechanical wheel to roll, and the mechanical leg can be used to guide the mechanical leg to extend and retract. The reference position of the mechanical leg can be used to guide the mechanical leg to rotate, the reference position of the body can be used to guide the body to move, and the reference attitude of the body can be used to guide the body to rotate.

[0327] This application embodiment allows for the selection of reference positions for one or more parts to control the robot's movement according to task requirements. For example, the robot can control itself to transition from a foot-supported state to a wheel-supported state and stand on a support surface based on the reference positions of each mechanical foot, each mechanical wheel, and the reference position and posture of the robot body.

[0328] In one example, the second desired task may include the reference position of the fuselage, the reference attitude of the fuselage, the reference position of the mechanical wheels, and the reference position of the mechanical feet.

[0329] Reference position of the fuselage: Based on the control time, the reference position of the fuselage at the control time can be determined from the reference movement trajectory of the fuselage, and denoted as .

[0330] Airframe reference attitude: Based on the control moment, the airframe reference attitude at the control moment can be determined from the airframe attitude reference change trajectory, denoted as Optionally, during the robot's movement, the body remains vertical at all times. If the reference posture is represented by the Euler angles of the waist, then the Euler angles of the waist are always zero.

[0331] Reference position of the mechanical wheel: For each mechanical wheel, its reference position at the control moment can be determined from its reference movement trajectory, and denoted as [reference position].

[0332] Reference position of the mechanical foot: For each mechanical foot, the reference position of the mechanical foot at the control time can be determined from the reference movement trajectory of the mechanical foot, and denoted as .

[0333] For example, the robot's second desired task at control time t can be represented as follows:

[0334]

[0335] in, Including the reference positions of the robot's various mechanical wheels, This includes the reference positions of the robot's various mechanical feet.

[0336] 2. Obtain the expected joint angle set corresponding to the second expected task. The expected joint angle set includes the expected joint angles of each joint used to control the robot.

[0337] In this embodiment of the application, the set of expected joint angles corresponding to the second expected task includes at least one of the following: the expected joint angles corresponding to the hip joint, ankle joint, wheel joint, extension joint, pitch joint, and lateral joint, respectively.

[0338] The desired joint angle refers to the angle to which a joint is expected to rotate. Among them, the desired joint angles for the hip joint, wheel joint, and telescopic joint are related to the reference position of the mechanical wheel; the desired joint angle for the ankle joint is related to the reference position of the mechanical foot; and the desired joint angles for the pitch joint and yaw joint are related to the reference position of the fuselage.

[0339] In one example, the desired set of joint angles corresponding to the second desired task can be calculated using the robot's whole-body kinematics model. Exemplarily, embodiments of this application may also include the following:

[0340] (1) Based on the whole-body kinematic model of the robot, a first kinematic model and a second kinematic model are obtained. The first kinematic model is used to indicate the relationship between the position of each part of the robot in the operating space and the angle of each joint of the robot in the joint space. The second kinematic model is used to indicate the relationship between the velocity of each part of the robot in the operating space and the angular velocity of each joint of the robot in the joint space.

[0341] A robot's whole-body kinematic model is a mathematical expression describing the robot's motion state and positional relationship. The robot's motion state can be represented by the angles of its joints. The whole-body kinematic model includes a forward kinematic model and a kinematic model. The forward kinematic model determines the robot's position by using the robot's joint angles. In this application's embodiments, the first kinematic model and the second kinematic model are determined based on the forward kinematic model.

[0342] For example, the forward kinematics model can be directly determined as the first kinematics model, denoted as x = f(q), where x is the position of each part of the robot in the operating space, and q is the angle of each joint of the robot in the joint space of the robot.

[0343] A variation of the forward kinematic model can be defined as the second kinematic model, denoted as . in, The speed of each part of the robot within the operating space. The angular velocities of each joint of the robot in the robot's joint space.

[0344] (2) Based on the first kinematic model and the second kinematic model, the kinematic equation to be solved is constructed, with the joint angles of each joint of the robot in the joint space as unknown variables.

[0345] For example, by simultaneously solving the first and second kinematic models and simplifying the equations, the kinematic equations to be solved can be expressed as follows:

[0346]

[0347] Where, q cmd J is the set of expected joint angles corresponding to each joint. t Let q be the Jacobian matrix corresponding to the second expected task t. act The actual set of joint angles corresponding to each joint can be obtained from the encoder of the joint motor corresponding to the joint, x des For the second expected task t (i.e., the reference position of the corresponding part of each joint), x act This refers to the actual location of the corresponding parts of each joint.

[0348] The second line of the kinematic equations to be solved gives (The first derivative of the reference position of each joint with respect to time (i.e., the reference velocity)), and The mapping relationship between (i.e., the first derivative of the expected joint angle set with respect to time) should be noted. It should be observed that the positions in the embodiments of this application are all characterized based on the world coordinate system.

[0349] Where, q act x des x act and Given the known variables, we can solve the kinematic equations to obtain the unknown variable q. cmd For example, the q cmd This can include the desired joint angles of each hip joint, ankle joint, wheel joint, telescopic joint, pitch joint, and lateral joint of the robot at the control moment.

[0350] (3) Substitute the robot’s second desired task at the control moment into the kinematic equation to be solved, and calculate the robot’s desired joint angle set at the control moment.

[0351] Optionally, the movement of the joint is also physically limited by the joint motor corresponding to the joint. To improve the rationality and accuracy of obtaining the desired joint angle set, this embodiment of the application also sets constraints in the process of solving the desired joint angle set. For example, the calculation process of the kinematic equations to be solved can be as follows:

[0352] By replacing the positions of the robot's various parts in the operational space in the kinematic equations to be solved with the robot's second desired task at the control moment, intermediate kinematic equations are obtained. Optionally, the x in the kinematic equations to be solved... des Replace with the second expected task The intermediate kinematic equations can then be obtained.

[0353] Construct the joint physical constraint expressions for the robot, which are used to constrain each joint of the robot. Optionally, based on the actual physical characteristics of the robot's joint motors, the desired joint angle set q in the unknown variables is... cmd Line limit, i.e., the joint physical constraint expression, can be: q 1B ≤q cmd ≤q ub ; where q lB and q ub These represent the minimum and maximum joint angles of the joint motor, respectively.

[0354] Under the constraints of the joint physical constraint expression, the desired set of joint angles of the robot at the control moment is calculated based on the intermediate kinematic equations. Optionally, a quadratic programming optimization method is used to construct the objective function of the intermediate kinematic equations; under the constraints of the joint physical constraint expression, the desired set of joint angles of the robot at the control moment is calculated with minimizing the objective function as the optimization objective.

[0355] For example, a linear quadratic regulator (LQR) is used to construct the objective function of the intermediate kinematic equations. Under the constraints of the joint physical constraint expressions, the desired set of joint angles at each control moment is calculated with minimizing the objective function as the optimization objective. This linear quadratic regulator is built based on the quadratic programming optimization method. Its essence is to find a multidimensional vector under linear constraints such that the quadratic objective function of the multidimensional vector is minimized (or maximized).

[0356] For example, first rewrite the intermediate kinematic equations in the form AX = B;

[0357] in,

[0358] The process of solving AX = B is essentially solving a system of linear equations. A and B are known variables, and X is an unknown variable. Here, a linear quadratic programming regulator can be used to construct the objective function of the intermediate kinematic equations.

[0359] Alternatively, the objective function of the intermediate kinematic equations can be expressed as follows:

[0360] Z = (AX - B) T W1(AX-B)+X T W2X;

[0361] Where W1 and W2 represent weight matrices.

[0362] By using a linear quadratic programming optimizer, under the constraints of the robot's joint physical constraints, and with the objective function minimized as the optimization goal, the unknown variable X can be obtained. The q values ​​in X can then be directly applied... cmd The desired set of joint angles is determined.

[0363] Alternatively, if the robot's model structure is relatively simple, then the robot's whole-body dynamics model (such as the forward kinematics model) is also relatively simple. In this case, the intermediate kinematic equations can be solved directly using the matrix inverse method, i.e., X = A. -1 B, to obtain the desired set of joint angles.

[0364] The first term in the objective function above represents the kinematic relationship, and the second term is to make the desired joint angle smaller in order to save energy. By using a linear quadratic programming optimizer to calculate the desired joint angle, we can ensure that the robot's motion conforms to the kinematic relationship while making the desired joint angle relatively small, thereby saving energy.

[0365] 3. Based on the desired joint angle set, move the mechanical foot to detach from the support surface, so that the robot can switch from a foot-supported state to a wheel-supported state and stand on the support surface.

[0366] Optionally, the desired joint angles of the desired joint angle set can be converted into corresponding desired torques, which are then used to control the movement of each joint, enabling the robot to transition from a foot-supported state to a wheel-supported state while standing on the support surface. Exemplarily, embodiments of this application may further include the following:

[0367] (1) Using a PD feedback controller, the second expected torque set corresponding to the expected joint angle set is calculated based on the expected joint angle set, the actual joint angle set corresponding to each joint, and the actual joint angular velocity set corresponding to each joint. The second expected torque set includes the second expected torque for each joint of the robot.

[0368] For example, the second desired torque set can be represented as follows:

[0369]

[0370] in, For the desired set of joint angles, For the actual joint angle set, For the actual set of joint angular velocities, k p，q and These correspond to the proportional coefficient for position feedback and the differential coefficient for velocity feedback, respectively.

[0371] k p，q and This ensures the accuracy of following the desired joint angle, thereby improving the robot's motion stability and accuracy. Following the desired joint angle effectively avoids the problem of poor force control transparency caused by following the desired acceleration; that is, when a small torque is applied, the joint remains stationary, but when the torque exceeds a certain value, the joint moves violently under the drive of a large force.

[0372] (2) According to the second expected torque set, the mechanical foot is moved to the point of being detached from the support surface, so that the robot changes from the foot support state to the wheel support state and stands on the support surface.

[0373] The second desired torque set includes the second desired torque of each joint of the robot at the control moment. The second desired torque is used to control the rotation of the joints. At any control moment, by simply driving the joint motors corresponding to each joint according to the second desired torque of each joint at that control moment, the second desired task can be achieved, that is, the mechanical foot is moved to leave the support surface, so that the robot changes from a foot-supported state to a wheel-supported state and stands on the support surface.

[0374] In summary, the technical solution provided in this application, by employing the robot's whole-body kinematics model and based on the robot's reference movement trajectory set, can accurately obtain the desired joint angle set corresponding to the execution of the second desired task. Furthermore, based on the desired joint angle set, it can accurately control the robot to switch from a foot-supported state to a wheel-supported state and stand on the support surface, thereby improving the robot's control accuracy.

[0375] Furthermore, by solving the intermediate kinematic equations under the constraints of the robot's joint physical constraint expressions, a reasonable and accurate set of expected joint angles can be obtained, thereby further improving the robot's control accuracy.

[0376] In some embodiments, after obtaining the first expected torque set corresponding to the first expected task and the second expected torque set corresponding to the second expected task, the embodiments of this application may also adopt a force-position hybrid approach to control the robot's movement based on the first expected torque set and the second expected torque set. The embodiments of this application may further include the following:

[0377] 1. Obtain the robot's reference movement trajectory set, which includes at least one of the following: reference movement trajectory of the robot body, reference movement trajectory of the mechanical legs, reference movement trajectory of the mechanical wheels, and reference posture change trajectory of the robot body.

[0378] 2. For any control moment corresponding to the robot, under the constraints of the robot's dynamics, based on the reference motion trajectory set, the first expected torque set of the robot at the control moment is obtained. The first expected torque set includes the first expected torque used to control each joint of the robot.

[0379] 3. Under the constraints of the robot's kinematics, based on the reference motion trajectory set, the second desired torque set of the robot at the controlled moment is obtained. The second desired torque set includes the second desired torque used to control each joint of the robot.

[0380] Optionally, the methods for obtaining the reference movement trajectory set, the first desired torque set, and the second desired torque set are the same as those described in the above embodiments. For content not described in the embodiments of this application, please refer to the above embodiments, and they will not be repeated here.

[0381] 4. Based on the first expected torque set and the second expected torque set, a weighted summation is obtained to obtain a mixed expected torque set. The mixed expected torque set is used to control the robot to switch from a wheel-supported state to a foot-supported state and stand on the support surface.

[0382] Optionally, in embodiments of this application, the first desired torque set and the second desired torque set are applied together to the robot to control the robot to switch from a foot-supported state to a wheel-supported state and stand on the support surface, such as determining the mixed desired torque set for the final control of the robot in a complementary manner.

[0383] For example, the mixed desired torque set can be represented as follows:

[0384]

[0385] Where α is the first desired torque set The weighting coefficients, (1-α) are the second expected torque set. The weighting coefficient. For example, α can be 80%, that is... The weighting factor is 80%. The weighting factor is 20%.

[0386] After obtaining the mixed expected torque set, the mechanical foot can be moved away from the support surface according to the mixed expected torque set, so that the robot can switch from the foot-supported state to the wheel-supported state and stand on the support surface.

[0387] The hybrid desired torque set includes the hybrid desired torques of each joint of the robot, which are used to control the rotation of the joints. At any control moment, by simply driving the joint motors corresponding to each joint according to the hybrid desired torque of each joint at that control moment, the simultaneous following of the first desired task and the second desired task can be achieved. That is, the robot can move under the guidance of the first desired task and the second desired task, such as following the desired accelerations corresponding to the first desired task and following the reference positions corresponding to the second desired task, thus realizing the control of the robot.

[0388] In summary, the technical solution provided in this application, by applying a first desired task (i.e., desired acceleration) and a second desired task (i.e., reference position) together to the robot, not only can the robot's joints have better dynamic performance under the combined effect of the desired acceleration and the reference position, but the following accuracy of the joint angles can also be taken into account, thereby effectively improving the robot's control stability and control accuracy. Furthermore, controlling the robot based on a hybrid desired torque set not only enables the robot to maintain its posture but also allows for smooth movements, thus enabling a smooth transition from a foot-supported state to a wheel-supported state.

[0389] In some embodiments, reference Figure 11 Taking the quadrupedal wheeled hybrid robot 1100 as an example, the technical solution provided in the embodiments of this application will be described.

[0390] In the embodiments of this application, the first desired torque set, the second desired torque set, or the mixed desired torque set can all be used to control the quadrupedal wheel hybrid robot 1100 to move in each stage, so that the quadrupedal wheel hybrid robot 1100 switches from wheel-supported state to foot-supported state and stands on the support surface.

[0391] Phase 1: Controlling the robot to transition from a quadrupedal support state to the first state.

[0392] First mechanical leg group 1101 (outer mechanical leg):

[0393] By controlling the desired torque (such as the first desired torque, the second desired torque, or a combination of desired torques) of the wheel joints of the first mechanical leg assembly 1101, the mechanical wheels of the first mechanical leg assembly 1101 are prevented from rolling, so as to keep the contact point between the first mechanical leg assembly 1101 and the support surface unchanged.

[0394] By controlling the extension and retraction of the extension and retraction joint of the first mechanical leg assembly 1101 with the desired torque of the joint, the extension and retraction amount of the corresponding extension and retraction joint of the first mechanical leg assembly 1101 is adjusted to 5 centimeters.

[0395] By controlling the desired torque of the ankle joint of the first mechanical leg assembly 1101, the ankle joint of the first mechanical leg assembly 1101 is rotated counterclockwise, and the joint angle of the ankle joint of the first mechanical leg assembly 1101 is adjusted to the first joint angle, so that the mechanical foot of the first mechanical leg assembly 1101 is adjusted to be detached from the support surface.

[0396] Second robotic leg assembly 1102 (inner robotic leg):

[0397] By controlling the desired torque of the wheel joint of the second mechanical leg assembly 1102, the mechanical wheels of the second mechanical leg assembly 1102 are prevented from rolling, so as to keep the contact point between the second mechanical leg assembly 1102 and the support surface unchanged.

[0398] By controlling the desired torque of the telescopic joint of the second mechanical leg assembly 1102, the telescopic joint of the second mechanical leg assembly 1102 is extended and retracted, so as to adjust the extension and retraction amount of the corresponding telescopic joint of the second mechanical leg assembly 1102 to 5 cm.

[0399] Body 1103: By controlling the pitch and lateral joints of body 1103 to prevent them from rotating through the desired torques corresponding to them, body 1103 remains vertical; under the influence of each telescopic joint, the height of body 1103 is reduced (i.e., the height of the center of mass of the quadrupedal wheel hybrid robot 1100 is reduced).

[0400] Phase Two: Controlling the robot to transition from the first state to the second state.

[0401] First mechanical leg group 1101 (outer mechanical leg):

[0402] By controlling the hip joint of the first mechanical leg assembly 1101 to rotate counterclockwise using the desired torque of the hip joint, the contact point between the first mechanical leg assembly 1101 and the support surface is moved to a position 60 centimeters in front of the contact point between the second mechanical leg assembly 1102 and the support surface.

[0403] By controlling the desired torque of the telescopic joint of the first mechanical leg assembly 1101, the telescopic joint of the first mechanical leg assembly 1101 is extended and retracted, thereby adapting and adjusting the length of the first mechanical leg assembly 1101.

[0404] Second robotic leg assembly 1102 (inner robotic leg):

[0405] By controlling the desired torque of the wheel joint of the second mechanical leg assembly 1102, the mechanical wheel of the second mechanical leg assembly 1102 is prevented from rolling, so as to keep the contact point between the corresponding mechanical wheel of the second mechanical leg assembly 1102 and the support surface unchanged.

[0406] By controlling the desired torque of the hip joint of the second mechanical leg assembly 1102, the hip joint of the second mechanical leg assembly 1102 is rotated clockwise so that the angle between the second mechanical leg assembly 1102 and the first mechanical leg assembly 1101 is adjusted to between zero and a preset angle threshold.

[0407] By controlling the desired torque of the telescopic joint of the second mechanical leg assembly 1102, the telescopic joint of the second mechanical leg assembly 1102 is extended and retracted, thereby adapting and adjusting the length of the second mechanical leg assembly 1102.

[0408] Body 1103: By controlling the desired torques corresponding to the pitch and yaw joints of body 1103, the pitch and yaw joints of body 1103 are kept from rotating, so that body 1103 remains vertical; under the action of each hip joint and each telescopic joint, body 1103 (such as the waist center) is moved to a position 30 cm in front of the contact point between the second mechanical leg group 1102 and the support surface, so that the center of mass of the quadrupedal wheeled hybrid robot 1100 falls on the center of the support area of ​​the quadrupedal wheeled hybrid robot 1100; under the action of each hip joint and each telescopic joint, the height of body 1103 remains unchanged.

[0409] Phase 3: Controlling the robot to transition from the second state to the four-wheel support state.

[0410] First mechanical leg assembly 1101 (outer mechanical leg): The first mechanical leg assembly 1101 is kept stationary by controlling the desired torques corresponding to the hip joint, extension joint, ankle joint and wheel joint of the first mechanical leg assembly 1101.

[0411] Second mechanical leg assembly 1102 (inner mechanical leg): The ankle joint of the second mechanical leg assembly 1102 is rotated counterclockwise by only the desired torque corresponding to the ankle joint of the second mechanical leg assembly 1102, so as to adjust the joint angle of the ankle joint of the second mechanical leg assembly 1102 to the first joint angle, so that the mechanical foot of the second mechanical leg assembly 1102 is adjusted to be detached from the support surface.

[0412] Fuselage 1103: By using the expected torques corresponding to each hip joint, each telescopic joint, each wheel joint, as well as the expected torques of the pitch joint and the yaw joint, the fuselage 1103 is kept stationary.

[0413] In summary, the technical solution provided in this application provides a solution for a robot with an inner mechanical leg and an outer mechanical leg connected to the body via a hip joint. Since the hip joint corresponding to the inner mechanical leg is located between the hip joints corresponding to the two outer mechanical legs, and at least one mechanical leg has a pair of coaxial mechanical wheels and mechanical feet on its foot away from the hip joint, when the robot stands on the support surface with the assistance of the mechanical feet and mechanical wheels, the inner and outer mechanical legs can work together to move the mechanical feet coaxial with the mechanical wheels away from the support surface. This allows the robot to stand on the support surface solely by the mechanical wheels, thus entering a wheel-supported state. This enables the wheel-legged robot with mechanical feet to switch from a foot-supported state to a wheel-supported state, allowing the robot to perform different tasks by switching states, thereby improving the robot's flexibility.

[0414] The following are embodiments of the apparatus described in this application, which can be used to execute the embodiments of the method described in this application. For details not disclosed in the apparatus embodiments of this application, please refer to the embodiments of the method described in this application.

[0415] refer to Figure 12 This diagram illustrates a block diagram of a robot control device according to an embodiment of this application. The device has the function of implementing the robot control method described above; this function can be implemented in hardware or by hardware executing corresponding software. The device can be a computer device as described above (such as a wheeled hybrid robot), or it can be housed within a computer device. Figure 12 As shown, the device 1200 includes a robot standing module 1201 and a state transition module 1202.

[0416] The robot standing module 1201 is used to stand on a support surface in a wheel-supported state, wherein, in the wheel-supported state, the robot stands only by means of the mechanical wheels.

[0417] The state transition module 1202 is used to move the mechanical foot to contact the support surface, so that the robot changes from the wheel support state to the foot support state and stands on the support surface. In the foot support state, the robot stands on the mechanical wheel with the assistance of the mechanical foot.

[0418] In some embodiments, the at least one inner mechanical leg forms a second mechanical leg assembly; such as Figure 13 As shown, the state transition module 1202 includes: a preparation state transition submodule 1202a and a wheel support state transition submodule 1202b.

[0419] The ready state transition submodule 1202a is used to transition the robot from the foot support state to a ready state standing on the support surface by adjusting at least one of the joint angle of the hip joint and the extension amount of the telescopic joint of the robot. The hip joint is used to control the rotation of the robot's mechanical legs, and the telescopic joint is used to adjust the length of the robot's mechanical legs. In the ready state, the robot satisfies at least one of the following: the included angle between the first mechanical leg group and the second mechanical leg group is zero, the extension amount of the telescopic joint is greater than the lower limit of the extension amount and less than the preset extension amount threshold, and the robot body is vertical.

[0420] The wheel support state transition submodule 1202b is used to move the mechanical foot away from the support surface by adjusting the joint angle of the robot's ankle joint, so that the robot transitions from the ready state to the wheel support state and stands on the support surface, wherein the ankle joint is used to control the rotation of the mechanical foot.

[0421] In some embodiments, when the mechanical feet are provided on at least one inner mechanical leg and at least one outer mechanical leg, in the first mechanical leg group and the second mechanical leg group, one mechanical leg group is a main mechanical leg group and the other mechanical leg group is an auxiliary mechanical leg group; the wheel support state conversion submodule 1202b is further used for:

[0422] The robot is controlled to transition from the ready state to the first state of standing on the support surface. In the first state, the projection point of the robot's center of mass on the support surface along the vertical direction falls within the projection area of ​​the mechanical foot corresponding to the auxiliary mechanical leg group on the support surface. The joint angle of the ankle joint of the main mechanical leg group is rotated to the first joint angle, which is used to ensure that the mechanical foot does not contact the support surface during the movement of the robot.

[0423] The robot is controlled to transition from the first state to the second state and stand on the support surface. In the second state, the angle between the main mechanical leg group and the auxiliary mechanical leg group is greater than zero and less than a preset angle threshold. The projection point of the robot's center of mass on the support surface along the vertical direction falls within the support area of ​​the robot. The support area refers to the area enclosed by the contact point between the robot and the support surface.

[0424] The robot is controlled to transition from the second state to the wheel-supported state and stand on the support surface. In the wheel-supported state, the mechanical feet corresponding to the auxiliary mechanical leg group are rotated to detach from the support surface, so that the mechanical wheels corresponding to the auxiliary mechanical leg group and the mechanical wheels corresponding to the main mechanical leg group form a support for the robot.

[0425] In some embodiments, the wheel support state transition submodule 1202b is further configured to rotate the ankle joint of the main mechanical leg assembly only in a direction close to the body, so as to control the robot to transition from the ready state to the first state of standing on the support surface.

[0426] In some embodiments, the wheel support state transition submodule 1202b is further configured to rotate the hip joint of the main mechanical leg group in the forward direction of the robot and the hip joint of the auxiliary mechanical leg group in the opposite direction of the forward direction while keeping the contact point between the mechanical wheel corresponding to the auxiliary mechanical leg group and the support surface unchanged, so as to control the robot to transition from the first state to the second state standing on the support surface.

[0427] In some embodiments, the wheel support state transition submodule 1202b is further configured to rotate the ankle joint of the auxiliary mechanical leg assembly only in a direction close to the body, so as to control the robot to transition from the second state to the wheel support state and stand on the support surface.

[0428] In some embodiments, when only one of the first and second mechanical leg groups is provided with the mechanical foot, the mechanical leg group with the mechanical foot is the target mechanical leg group, and the mechanical leg group without the mechanical foot is the non-target mechanical leg group; the wheel support state transition submodule 1202b is further used for:

[0429] The robot is controlled to transition from the ready state to the first state and stand on the support surface. In the first state, the angle between the target mechanical leg group and the non-target mechanical leg group is greater than zero and less than a preset angle threshold. The projection point of the robot's center of mass on the support surface in the vertical direction falls within the support area of ​​the robot. The support area refers to the area enclosed by the contact point between the robot and the support surface.

[0430] The robot is controlled to transition from the first state to the wheel-supported state and stand on the support surface. In the wheel-supported state, the mechanical foot corresponding to the target mechanical leg group is rotated to detach from the support surface, so that the mechanical wheel corresponding to the target mechanical leg group and the mechanical wheel corresponding to the non-target mechanical leg group form a support for the robot.

[0431] In some embodiments, the wheel support state transition submodule 1202b is further configured to rotate the hip joint of the non-target mechanical leg group in the forward direction of the robot and rotate the hip joint of the target mechanical leg group in the opposite direction of the forward direction while keeping the contact point between the mechanical wheel corresponding to the target mechanical leg group and the support surface unchanged, so as to control the robot to transition from the ready state to the first state standing on the support surface.

[0432] In some embodiments, the wheel support state transition submodule 1202b is further configured to rotate the ankle joint of the target mechanical leg assembly only in a direction close to the body, so as to control the robot to transition from the first state to the wheel support state and stand on the support surface.

[0433] In some embodiments, such as Figure 13As shown, the device 1200 further includes a center of gravity height adjustment module 1203. The center of gravity height adjustment module 1203 is used to adjust the length of the mechanical leg via a telescopic joint on the mechanical leg, and to adjust the angle between the inner and outer mechanical legs via a hip joint on the mechanical leg, thereby lowering the height of the robot's center of gravity. This allows the robot to transition from a wheel-supported state to a wheeled motion state, standing on the support surface. In the wheeled motion state, the robot performs tasks solely by standing on the support surface using only the mechanical wheels.

[0434] In some embodiments, such as Figure 13 As shown, the device 1200 further includes: a movement trajectory acquisition module 1204 and a desired torque acquisition module 1205.

[0435] The movement trajectory acquisition module 1204 is used to acquire a reference movement trajectory set of the robot, the reference movement trajectory set including at least one of the following: the reference movement trajectory of the robot body, the reference movement trajectory of the mechanical foot, the reference movement trajectory of the mechanical wheel, and the attitude reference change trajectory of the robot body.

[0436] The desired torque acquisition module 1205 is used to obtain, for any control moment corresponding to the robot, a first desired torque set of the robot at the control moment under the constraints of the robot's dynamics, based on the reference movement trajectory set. The first desired torque set includes the first desired torque for controlling each joint of the robot.

[0437] The desired torque acquisition module 1205 is further configured to obtain a second desired torque set of the robot at the control moment based on the reference movement trajectory set under the kinematic constraints of the robot. The second desired torque set includes second desired torques for controlling each joint of the robot.

[0438] The expected torque acquisition module 1205 is further configured to obtain a mixed expected torque set by weighted summation based on the first expected torque set and the second expected torque set, and the mixed expected torque set is used to control the robot to switch from the foot support state to the wheel support state and stand on the support surface.

[0439] In some embodiments, the reference movement trajectory of the body is used to control the center of mass of the robot to be located within the support area of ​​the robot, the support area being the area enclosed by the contact points between the robot and the support surface.

[0440] In summary, the technical solution provided in this application provides a solution for a robot with an inner mechanical leg and an outer mechanical leg connected to the body via a hip joint. Since the hip joint corresponding to the inner mechanical leg is located between the hip joints corresponding to the two outer mechanical legs, and at least one mechanical leg has a pair of coaxial mechanical wheels and mechanical feet on its foot away from the hip joint, when the robot stands on the support surface with the assistance of the mechanical feet and mechanical wheels, the inner and outer mechanical legs can work together to move the mechanical feet coaxial with the mechanical wheels away from the support surface. This allows the robot to stand on the support surface solely by the mechanical wheels, thus entering a wheel-supported state. This enables the wheel-legged robot with mechanical feet to switch from a foot-supported state to a wheel-supported state, allowing the robot to perform different tasks by switching states, thereby improving the robot's flexibility.

[0441] It should be noted that the apparatus provided in the above embodiments is only illustrated by the division of the above functional modules when implementing its functions. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the apparatus and method embodiments provided in the above embodiments belong to the same concept, and the specific implementation process can be found in the method embodiments, which will not be repeated here.

[0442] Please refer to Figure 14 This diagram illustrates a simplified structural block diagram of a computer device 1400 provided in one embodiment of this application. The computer device 1400 can be any electronic device capable of data calculation, processing, and storage. The computer device 1400 can be used to implement the robot control method provided in the above embodiments.

[0443] Typically, computer device 1400 includes a processor 1401 and a memory 1402.

[0444] Processor 1401 may include one or more processing cores, such as a quad-core processor, an octa-core processor, etc. Processor 1401 may be implemented using at least one hardware form selected from DSP (Digital Signal Processing), FPGA (Field Programmable Gate Array), and PLA (Programmable Logic Array). Processor 1401 may also include a main processor and a coprocessor. The main processor, also known as a CPU (Central Processing Unit), is used to process data in the wake-up state; the coprocessor is a low-power processor used to process data in the standby state. In some embodiments, processor 1401 may integrate a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the screen. In some embodiments, processor 1401 may also include an AI processor for handling computational operations related to machine learning.

[0445] The memory 1402 may include one or more computer-readable storage media, which may be non-transitory. The memory 1402 may also include high-speed random access memory and non-volatile memory, such as one or more disk storage devices or flash memory devices. In some embodiments, the non-transitory computer-readable storage media in the memory 1402 is used to store a computer program configured to be executed by one or more processors to implement the robot control method described above.

[0446] Those skilled in the art will understand that Figure 14 The structure shown does not constitute a limitation on the computer device 1400, and may include more or fewer components than shown, or combine certain components, or use different component arrangements.

[0447] In some embodiments, a chip is also provided, wherein a computer program is stored in the chip, the computer program being loaded and executed by a processor to implement the robot control method described above.

[0448] In some embodiments, a computer-readable storage medium is also provided, wherein a computer program is stored therein, which, when executed by a processor of a computer device, implements the above-described robot control method.

[0449] Optionally, the computer-readable storage medium may include: ROM (Read-Only Memory), RAM (Random-Access Memory), SSD (Solid State Drives), or optical disc, etc. The random access memory may include ReRAM (Resistance Random Access Memory) and DRAM (Dynamic Random Access Memory).

[0450] In some embodiments, a computer program product is also provided, the computer program product including a computer program stored in a computer-readable storage medium. A processor of a computer device reads the computer program from the computer-readable storage medium, and the processor executes the computer program, causing the computer device to perform the robot control method described above.

[0451] It should be noted that, in this application embodiment, before and during the collection of user-related data, a prompt interface, pop-up window, or voice prompt message can be displayed. This prompt interface, pop-up window, or voice prompt message is used to inform the user that their relevant data is being collected. This ensures that the application only begins executing the steps related to collecting user-related data after receiving confirmation from the user regarding the prompt interface or pop-up window; otherwise (i.e., without receiving confirmation from the user), the steps to collect user-related data end, meaning no user-related data is collected. In other words, all user data collected in this application is processed strictly in accordance with the requirements of relevant national laws and regulations. The informed consent or separate consent of the personal information subject is obtained only with the user's consent and authorization. Subsequent data use and processing are conducted within the scope of laws and regulations and the authorization of the personal information subject. Furthermore, the collection, use, and processing of relevant user data must comply with the relevant laws, regulations, and standards of the relevant countries and regions. For example, the actual location, real environment, and robots involved in this application are all obtained with full authorization.

[0452] It should be understood that "multiple" as used herein refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. Furthermore, the step numbers described herein are merely illustrative of one possible execution order. In some other embodiments, the steps may not be executed in numerical order, such as two steps with different numbers being executed simultaneously, or two steps with different numbers being executed in the reverse order of the illustration. This application does not limit this.

[0453] The above description is merely an exemplary embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for controlling a robot, characterized in that, The robot includes a body, two outer mechanical legs connected to the body via hip joints, and at least one inner mechanical leg. The hip joint corresponding to the at least one inner mechanical leg is located between the hip joints corresponding to the two outer mechanical legs. The rotation centers of the hip joints corresponding to the outer and inner mechanical legs are located in the same vertical plane. At least one of the robot's mechanical legs has a pair of coaxial mechanical wheels and a mechanical foot at its foot portion away from the hip joint. The two outer mechanical legs form a first mechanical leg group, and the at least one inner mechanical leg forms a second mechanical leg group. The method includes: The robot stands on a support surface in a foot-supported state, wherein, in the foot-supported state, the robot stands upright with the assistance of the mechanical wheels via the mechanical feet; By adjusting at least one of the joint angle of the hip joint and the extension / retraction amount of the robot's telescopic joint, the robot transitions from the foot-supported state to a ready state standing on the support surface. The hip joint is used to control the rotation of the robot's mechanical legs, and the telescopic joint is used to adjust the length of the robot's mechanical legs. In the ready state, the robot satisfies at least one of the following: the included angle between the first mechanical leg group and the second mechanical leg group is zero, the extension / retraction amount of the telescopic joint is greater than the lower limit of the extension / retraction amount and less than the preset extension / retraction amount threshold, and the robot body is vertical. By adjusting the joint angle of the robot's ankle joint, the mechanical foot is moved away from the support surface, so that the robot transitions from the ready state to the wheel-supported state and stands on the support surface. In the wheel-supported state, the robot stands only on the mechanical wheels, and the ankle joint is used to control the rotation of the mechanical foot.

2. The method according to claim 1, characterized in that, When the mechanical feet are provided on at least one inner mechanical leg and at least one outer mechanical leg, in the first mechanical leg group and the second mechanical leg group, one mechanical leg group is the main mechanical leg group and the other mechanical leg group is the auxiliary mechanical leg group. The step of moving the mechanical foot away from the support surface by adjusting the joint angle of the robot's ankle joint, thereby transitioning the robot from the ready state to the wheel-supported state and standing on the support surface, includes: The robot is controlled to transition from the ready state to the first state of standing on the support surface. In the first state, the projection point of the robot's center of mass on the support surface along the vertical direction falls within the projection area of ​​the mechanical foot corresponding to the auxiliary mechanical leg group on the support surface. The joint angle of the ankle joint of the main mechanical leg group is rotated to the first joint angle, which is used to ensure that the mechanical foot does not contact the support surface during the movement of the robot. The robot is controlled to transition from the first state to the second state and stand on the support surface. In the second state, the angle between the main mechanical leg group and the auxiliary mechanical leg group is greater than zero and less than a preset angle threshold. The projection point of the robot's center of mass on the support surface along the vertical direction falls within the support area of ​​the robot. The support area refers to the area enclosed by the contact point between the robot and the support surface. The robot is controlled to transition from the second state to the wheel-supported state and stand on the support surface. In the wheel-supported state, the mechanical feet corresponding to the auxiliary mechanical leg group are rotated to detach from the support surface, so that the mechanical wheels corresponding to the auxiliary mechanical leg group and the mechanical wheels corresponding to the main mechanical leg group form a support for the robot.

3. The method according to claim 2, characterized in that, The control of the robot to transition from the ready state to the first state of standing on the support surface includes: The main mechanical leg assembly's ankle joints are rotated only in a direction close to the body to control the robot to transition from the ready state to the first state of standing on the support surface.

4. The method according to claim 2 or 3, characterized in that, The control of the robot to transition from the first state to the second state of standing on the support surface includes: While keeping the contact point between the mechanical wheel corresponding to the auxiliary mechanical leg group and the support surface unchanged, the hip joint of the main mechanical leg group is rotated in the forward direction of the robot, and the hip joint of the auxiliary mechanical leg group is rotated in the opposite direction of the forward direction, so as to control the robot to switch from the first state to the second state of standing on the support surface.

5. The method according to any one of claims 2 to 4, characterized in that, The control of the robot to transition from the second state to the wheel-supported state and stand on the support surface includes: The ankle joint of the auxiliary mechanical leg assembly is rotated only in the direction close to the body to control the robot to switch from the second state to the wheel-supported state and stand on the support surface.

6. The method according to claim 1, characterized in that, When only one of the first and second mechanical leg groups is equipped with the mechanical foot, the mechanical leg group equipped with the mechanical foot is the target mechanical leg group, and the mechanical leg group without the mechanical foot is the non-target mechanical leg group. The step of moving the mechanical foot away from the support surface by adjusting the joint angle of the robot's ankle joint, thereby transitioning the robot from the ready state to the wheel-supported state and standing on the support surface, includes: The robot is controlled to transition from the ready state to the first state and stand on the support surface. In the first state, the angle between the target mechanical leg group and the non-target mechanical leg group is greater than zero and less than a preset angle threshold. The projection point of the robot's center of mass on the support surface in the vertical direction falls within the support area of ​​the robot. The support area refers to the area enclosed by the contact point between the robot and the support surface. The robot is controlled to transition from the first state to the wheel-supported state and stand on the support surface. In the wheel-supported state, the mechanical foot corresponding to the target mechanical leg group is rotated to detach from the support surface, so that the mechanical wheel corresponding to the target mechanical leg group and the mechanical wheel corresponding to the non-target mechanical leg group form a support for the robot.

7. The method according to claim 6, characterized in that, The control of the robot to transition from the ready state to the first state of standing on the support surface includes: While keeping the contact point between the mechanical wheel corresponding to the target mechanical leg group and the support surface unchanged, rotate the hip joint of the non-target mechanical leg group in the forward direction of the robot, and rotate the hip joint of the target mechanical leg group in the opposite direction of the forward direction, so as to control the robot to switch from the ready state to the first state standing on the support surface.

8. The method according to claim 6 or 7, characterized in that, The control of the robot to transition from the first state to the wheel-supported state and stand on the support surface includes: The target mechanical leg assembly's ankle joint is rotated only in a direction close to the body to control the robot to transition from the first state to the wheel-supported state and stand on the support surface.

9. The method according to any one of claims 1 to 8, characterized in that, After adjusting the joint angle of the robot's ankle joint to move the mechanical foot away from the support surface, so that the robot transitions from the ready state to the wheel-supported state and stands on the support surface, the method further includes: The robot's center of gravity height is lowered by adjusting the length of the mechanical leg through the telescopic joint on the mechanical leg and adjusting the angle between the inner and outer mechanical legs through the hip joint on the mechanical leg, so that the robot can switch from the wheel-supported state to the wheeled motion state and stand on the support surface. In the wheeled motion state, the robot performs tasks by standing on the support surface only through the mechanical wheels.

10. The method according to any one of claims 1 to 9, characterized in that, The method further includes: Obtain a reference movement trajectory set for the robot, the reference movement trajectory set including at least one of the following: reference movement trajectory of the robot body, reference movement trajectory of the mechanical legs, reference movement trajectory of the mechanical wheels, and attitude change trajectory of the robot body; For any control moment corresponding to the robot, under the constraints of the robot's dynamics, based on the reference movement trajectory set, a first expected torque set of the robot at the control moment is obtained. The first expected torque set includes the first expected torque for controlling each joint of the robot. Under the constraints of the robot's kinematics, based on the reference motion trajectory set, a second desired torque set of the robot at the control moment is obtained. The second desired torque set includes the second desired torque for controlling each joint of the robot. Based on the first expected torque set and the second expected torque set, a weighted summation is obtained to obtain a mixed expected torque set, which is used to control the robot to switch from the foot-supported state to the wheel-supported state and stand on the support surface.

11. The method according to claim 10, characterized in that, The reference movement trajectory of the robot body is used to control the center of mass of the robot to be located within the support area of ​​the robot, where the support area refers to the area enclosed by the contact point between the robot and the support surface.

12. A control device for a robot, characterized in that, The robot includes a body, two outer mechanical legs connected to the body via hip joints, and at least one inner mechanical leg. The hip joint corresponding to the at least one inner mechanical leg is located between the hip joints corresponding to the two outer mechanical legs. The rotation centers of the hip joints corresponding to the outer and inner mechanical legs are located in the same vertical plane. At least one of the robot's mechanical legs has a pair of coaxial mechanical wheels and a mechanical foot at its foot portion away from the hip joint. The two outer mechanical legs form a first mechanical leg group, and the at least one inner mechanical leg forms a second mechanical leg group. The device includes: A robot standing module is used to stand on a support surface in a foot-supported state, wherein, in the foot-supported state, the robot stands by means of mechanical feet assisted by mechanical wheels; A state transition module is used to transition the robot from a foot-supported state to a ready state standing on the support surface by adjusting at least one of the joint angle of the hip joint and the extension / retraction amount of the robot's telescopic joint. The hip joint is used to control the rotation of the robot's mechanical legs, and the telescopic joint is used to adjust the length of the robot's mechanical legs. In the ready state, the robot satisfies at least one of the following: the included angle between the first mechanical leg group and the second mechanical leg group is zero, the extension / retraction amount of the telescopic joint is greater than a lower limit of the extension / retraction amount and less than a preset extension / retraction amount threshold, and the robot body is vertical. By adjusting the joint angle of the robot's ankle joint, the mechanical foot is moved to detach from the support surface, so that the robot transitions from the ready state to a wheel-supported state standing on the support surface. In the wheel-supported state, the robot stands only on the mechanical wheels, and the ankle joint is used to control the rotation of the mechanical foot.

13. A chip product, characterized in that, The chip product stores a computer program, which is loaded and executed by a processor to implement the robot control method as described in any one of claims 1 to 11.

14. A computer device, characterized in that, The computer device includes a processor and a memory, the memory storing a computer program that is loaded and executed by the processor to implement the robot control method as described in any one of claims 1 to 11.

15. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which is loaded and executed by a processor to implement the robot control method as described in any one of claims 1 to 11.

16. A computer program product, characterized in that, The computer program product includes a computer program stored in a computer-readable storage medium, and a processor reads from and executes the computer program to implement the robot control method as described in any one of claims 1 to 11.

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