Mobile robot chassis, control method thereof and mobile robot

Abstract

The embodiment of the invention provides a mobile robot chassis, a control method of the mobile robot chassis and a mobile robot, the control method of the mobile robot chassis is applied to a control unit in the mobile robot chassis, the mobile robot chassis further comprises a frame and four driving assemblies, and the four driving assemblies are symmetrically arranged on the two sides of the frame; the driving assembly comprises a connecting structure, two motors and two driving wheels with the same diameter, and each motor is connected with one driving wheel; the connecting structure is rotationally connected with the frame; the method comprises the steps that a target movement vector is received, the target movement vector comprises a first to-be-moved speed of a chassis of the mobile robot in the first direction, a second to-be-moved speed of the chassis of the mobile robot in the second direction and an in-situ spin angular speed, and the first direction is horizontally perpendicular to the second direction; determining the rotating speed of each driving wheel according to the target movement vector; and when the two motors in the same driving assembly are controlled to respectively drive the connected driving wheels to rotate in opposite directions, the driving assembly rotates in situ.

Description

Technical Field

[0001] This invention relates to the field of robotics, and in particular to a mobile robot chassis and its control method, and a mobile robot. Background Technology

[0002] Mobile robots are gradually moving from structured, predictable industrial environments to unstructured, dynamic, and complex everyday and commercial scenarios, such as warehousing and logistics, hotel services, hospital delivery, and even home environments. This trend places unprecedentedly high demands on the mobility of robots, namely, extremely high space utilization, flexible and maneuverable obstacle avoidance capabilities, stable and precise motion performance, and low total cost of ownership.

[0003] A mobile robot chassis is the fundamental platform for realizing spatial movement and task execution. Traditional differential drive chassis use two independently driven ordinary wheels as active wheels, one on each side, in conjunction with one or more passive omnidirectional wheels. Steering is achieved by controlling the speed difference between the left and right wheels. This relies on the passive omnidirectional wheels, which are non-driven components. Their guidance and support depend passively on ground friction. During startup, braking, or on uneven ground, they are prone to directional instability, slippage, or jamming, making it difficult to guarantee motion accuracy. Furthermore, due to the limitations of their kinematic model, lateral translation is not possible, meaning lateral movement cannot be performed without changing the robot's orientation. Therefore, how to provide a high-precision omnidirectional mobile robot chassis and its control method is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide a mobile robot chassis and its control method, as well as a mobile robot, to achieve high motion accuracy and omnidirectional motion of the mobile robot chassis. The specific technical solution is as follows:

[0005] This application provides a mobile robot chassis control method, applied to a control unit in the mobile robot chassis. The mobile robot chassis further includes a frame and four drive components, the four drive components being symmetrically arranged on both sides of the frame. Each drive component includes a connecting structure, two motors, and two drive wheels of the same diameter, each motor being connected to one drive wheel. The connecting structure is rotatably connected to the frame. The method includes:

[0006] Receive a target movement vector, the target movement vector including: a first speed to be moved along a first direction, a second speed to be moved along a second direction, and a spin angular velocity in place, wherein the first direction and the second direction are horizontally perpendicular;

[0007] Based on the target movement vector, determine the rotational speed of each drive wheel;

[0008] When two motors in the same drive assembly drive the connected drive wheels to rotate in opposite directions, the drive assembly rotates in place.

[0009] This application proposes a mobile robot chassis. Using the method of any of the above embodiments, the mobile robot chassis includes a frame, four drive components, and a control unit. The four drive components are symmetrically arranged on both sides of the frame. Each drive component includes a connecting structure, two motors, and two drive wheels of the same diameter. The two motors are mounted on the connecting structure and disposed between the two drive wheels, with each motor connected to one drive wheel. The connecting structure has a vertical rotating shaft at its upper end, and the connecting structure is rotatably connected to the frame via the rotating shaft. The control unit is capable of controlling two motors in the same drive component to drive their connected drive wheels to rotate in opposite directions, so that each drive component rotates in place.

[0010] This application provides a mobile robot, which includes the aforementioned mobile robot chassis. The mobile robot also includes: a memory for storing executable instructions; and a processor for executing the executable instructions stored in the memory to implement the steps included in the aforementioned mobile robot chassis control method.

[0011] This application provides a mobile robot chassis control device, applied to a control unit in the mobile robot chassis. The mobile robot chassis further includes a frame and four drive components, the four drive components being symmetrically arranged on both sides of the frame. Each drive component includes a connecting structure, two motors, and two drive wheels of the same diameter, each motor being connected to one drive wheel. The connecting structure is rotatably connected to the frame. The device includes:

[0012] A vector receiving module is used to receive a target movement vector, the target movement vector including: a first speed to be moved along a first direction, a second speed to be moved along a second direction, and a spin angular velocity in place of the mobile robot chassis, wherein the first direction and the second direction are horizontally perpendicular;

[0013] The rotational speed calculation module is used to calculate the rotational speed of each drive wheel based on the target movement vector.

[0014] The first control module is used to control the drive assembly to rotate in place when the two motors in the same drive assembly drive the connected drive wheels to rotate in opposite directions.

[0015] This application provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the method steps of any of the above embodiments.

[0016] This application provides a computer program product containing instructions that, when run on a computer, cause the computer to perform any of the method steps of any of the above embodiments.

[0017] Beneficial effects of the embodiments of the present invention:

[0018] The technical solution of this application embodiment can control each motor to drive the connected drive wheel to rotate at its corresponding speed. When two drive wheels in the same drive assembly rotate in opposite directions, the drive assembly rotates in place, thereby adjusting the orientation of the drive wheels to adjust the movement direction of the mobile robot chassis and controlling the mobile robot chassis to perform omnidirectional movement. Furthermore, each drive wheel can be controlled independently, resulting in higher movement precision. The mobile robot chassis includes a frame, four drive assemblies, and a control unit. Each drive assembly includes a connecting structure, two motors, and two drive wheels. The connecting structure has a vertical rotating shaft at its upper end, and the connecting structure is rotatably connected to the frame via the rotating shaft, allowing the drive assembly to rotate relative to the frame. Each motor is connected to one drive wheel, allowing each drive wheel to rotate independently. The control unit can control the two motors in the same drive assembly to drive their connected drive wheels to rotate in opposite directions, causing each drive assembly to rotate in place, thereby adjusting the orientation of the drive wheels to adjust the movement direction of the mobile robot chassis and achieving omnidirectional movement of the mobile robot chassis. Moreover, in this application embodiment, each drive wheel of the mobile robot chassis is an active wheel, with each motor controlling one drive wheel, resulting in higher movement precision.

[0019] Of course, implementing any product or method of the present invention does not necessarily require achieving all of the advantages described above at the same time. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained based on these drawings.

[0021] Figure 1 A flowchart illustrating the mobile robot chassis control method provided in this application embodiment. Figure 1 ;

[0022] Figure 2 This is a schematic diagram of the movement of the mobile robot chassis along the X direction according to an embodiment of this application;

[0023] Figure 3 This is a schematic diagram of the movement of the mobile robot chassis along the Y direction according to an embodiment of this application;

[0024] Figure 4A flowchart illustrating the mobile robot chassis control method provided in this application embodiment. Figure 2 ;

[0025] Figure 5 A flowchart illustrating the mobile robot chassis control method provided in this application embodiment. Figure 3 ;

[0026] Figure 6 This is a schematic diagram of the motion of the mobile robot chassis spinning in place according to an embodiment of this application;

[0027] Figure 7 A flowchart illustrating the mobile robot chassis control method provided in this application embodiment. Figure 4 ;

[0028] Figure 8 This is a schematic diagram of the structure of the mobile robot chassis according to an embodiment of this application;

[0029] Figure 9 This is a schematic diagram showing the position of the target circle in an embodiment of this application;

[0030] Figure 10 This is an isometric view of the driving component in the embodiments of this application;

[0031] Figure 11 This is a side view of the driving component in an embodiment of this application;

[0032] Figure 12 This is a schematic diagram of the exploded structure of the driving component in the embodiments of this application. Figure 1 ;

[0033] Figure 13 This is a schematic diagram showing the location of the motor mounting part in an embodiment of this application;

[0034] Figure 14 This is a schematic diagram of the exploded structure of the driving component in the embodiments of this application. Figure 2 ;

[0035] Figure 15 This is a schematic diagram of the drive component in the embodiments of this application, omitting one drive wheel;

[0036] Figure 16 This is a cross-sectional view of the driving component in an embodiment of this application;

[0037] Figure 17 This is a schematic diagram of the structure of a mobile robot provided in an embodiment of this application;

[0038] Figure 18 This is a schematic diagram of the structure of a mobile robot chassis control device provided in an embodiment of this application.

[0039] Explanation of reference numerals in the attached figures:

[0040] Frame 100; Frame body 110; Clearance space 120; Connecting part 130; Horizontal support 131; Vertical support 132;

[0041] Drive assembly 200; connecting structure 210; rotating shaft 211; connecting column 2111; connecting block 2112; rigid bridge 212; groove 2121; mounting flange 2122; output shaft 213; bearing washer 214; crossed roller bearing 215; bearing cover plate 216; bearing bracket 217; motor 220; drive wheel 230;

[0042] Target circle C; Wheelset center point A;

[0043] Vector receiving module 301; Rotation speed calculation module 302; First control module 303;

[0044] Processor 401; Memory 402; Communication bus 403; Communication interface 404. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art based on this application are within the scope of protection of the present invention.

[0046] To achieve high motion accuracy and omnidirectional motion of the mobile robot chassis, embodiments of this application propose a mobile robot chassis and its control method, as well as a mobile robot.

[0047] like Figure 1 As shown, Figure 1 A flowchart illustrating the mobile robot chassis control method provided in this application embodiment. Figure 1 This application proposes a mobile robot chassis control method, applied to a control unit in a mobile robot chassis. The mobile robot chassis also includes a frame and four drive components, which are symmetrically arranged on both sides of the frame. Each drive component includes a connecting structure, two motors, and two drive wheels of the same diameter, with each motor connected to one drive wheel. The connecting structure is rotatably connected to the frame. The method includes:

[0048] S101: Receive target movement vector.

[0049] The target movement vector includes: the first velocity V to be moved by the mobile robot chassis along the first direction. X The second speed V to be moved along the second direction y The stationary spin angular velocity ω is perpendicular to the first direction and the second direction.

[0050] Optionally, the control unit can receive target movement vectors from the upper-level navigation system or input by the user. The user can input the target movement vector by pressing buttons on the remote control. The control unit and the upper-level navigation system can be connected via wired or wireless connection.

[0051] S102: Determine the rotational speed of each drive wheel based on the target movement vector;

[0052] When the drive wheels are directly connected to the motors, the rotational speed of each drive wheel is equal to the rotational speed of each motor.

[0053] The rotational speed of each drive wheel can be calculated. The control unit can be pre-set with a kinematic inverse solution model of the structure of the mobile robot chassis based on the embodiment of this application. This model calculates the target rotational speed required for the two drive wheels in each drive component based on the target movement vector.

[0054] S103: When two motors in the same drive assembly drive the connected drive wheels to rotate in opposite directions, the drive assembly rotates in place.

[0055] The control unit sends the target rotation speed to the corresponding motor driver, which then drives the motor to reach the target speed. By controlling the two drive wheels in the same drive assembly to rotate in opposite directions, the connecting shaft of the drive assembly can be rotated relative to the frame, thereby controlling the orientation of the drive wheels and switching the motion state of the mobile robot chassis.

[0056] The mobile robot chassis control method of this application embodiment controls each motor to drive the connected drive wheel to rotate at its corresponding speed. When two drive wheels in the same drive assembly rotate in opposite directions, the drive assembly rotates in place, thereby adjusting the orientation of the drive wheels to adjust the movement direction of the mobile robot chassis and controlling the mobile robot chassis to perform omnidirectional movement. Moreover, each drive wheel can be controlled independently, resulting in higher movement accuracy.

[0057] Based on the above step S103, the forward direction of the drive wheel in the drive assembly can be rotated from the first direction to the second direction.

[0058] like Figure 2 and Figure 3 As shown, Figure 2 This is a schematic diagram of the movement of the mobile robot chassis along the X direction according to an embodiment of this application. Figure 3 This is a schematic diagram of the movement of the mobile robot chassis along the Y direction according to an embodiment of this application. Taking the first direction as the X direction and the second direction as the Y direction as an example, when the mobile robot chassis needs to move from... Figure 2 The motion state along the X direction is switched as shown. Figure 3The motion state shown along the Y direction requires adjusting the posture of each drive wheel first. The control unit controls the two drive wheels of the same drive component to rotate in opposite directions, so that the drive component can rotate relative to the frame, thereby adjusting the drive wheel's axis of rotation from extending along the Y direction to extending along the X direction. After the posture of the drive wheel is adjusted, the subsequent step S104 can be executed to make the mobile robot chassis move linearly along the Y direction, completing the switch of motion state.

[0059] like Figure 4 As shown, Figure 4 A flowchart illustrating the mobile robot chassis control method provided in this application embodiment. Figure 2 , and the aforementioned Figure 1 Compared to the illustrated embodiment, when the forward direction of the drive wheels is the same, the above method further includes the step S104.

[0060] S104: Controls each motor to drive the connected drive wheel to rotate at the same speed, so that the mobile robot chassis moves in a straight line.

[0061] Linear motion includes the forward, backward, translational, and diagonal movements of the mobile robot chassis.

[0062] like Figure 2 As shown, the shafts of all drive wheels and the output shaft of the motor extend along the Y direction, and the input target movement vector V X =V、V y =0, ω=0, V is not 0. Calculate that the target rotation speed of all drive wheels is equal, all motors rotate in the same direction at the same speed, driving all drive wheels to rotate in the same direction at the same speed, so that the mobile robot chassis moves forward or backward in the X direction.

[0063] like Figure 3 As shown, the shafts of all drive wheels and the output shaft of the motor extend along the X direction, and the input target movement vector V X =0、V y =V, ω=0, V is not 0, calculate that the target speed of all drive wheels is equal, all motors rotate in the same direction at the same speed, driving all drive wheels to rotate in the same direction at the same speed, so that the chassis of the mobile robot moves laterally in the Y direction.

[0064] All drive wheel shafts and motor output shafts extend along a third direction, which forms a certain angle with the X and Y directions. The input target movement vector V X =V、V y =V', ω=0, V and V' are not 0, the target speed of all drive wheels is calculated to be equal, all motors rotate in the same direction at the same speed, driving all drive wheels to rotate in the same direction at the same speed, so that the chassis of the mobile robot moves obliquely.

[0065] Mobile robot chassis from Figure 2 The motion state shown has been switched to Figure 3 The motion state shown can be achieved by first adjusting the attitude of the drive wheels based on step S103, and then by making the mobile robot chassis move linearly along the Y direction based on step S104.

[0066] During the switching of the mobile robot chassis motion state, the first target rotation speed can be calculated by inputting the target movement vector first, and the drive wheel attitude can be adjusted by executing step S103 based on the first target rotation speed; then the second target rotation speed can be calculated by inputting the target movement vector, and the second target rotation speed can be calculated by executing step S104 to move straight or executing the subsequent step S105 to spin in place.

[0067] Sensors can be mounted on the chassis of the mobile robot to assist the control unit in speed calculations. For example, a camera can be used as a sensor to determine whether to calculate the first or second target rotational speed based on the posture of the drive wheels captured by the camera.

[0068] For example, when the chassis of a mobile robot needs to be removed from... Figure 2 The motion state shown has been switched to Figure 3 The motion state is shown, and the target movement vector V is input. X =0、V y =V, ω=0, V is not 0. The camera captures an image to determine the orientation of the drive wheels. If all drive wheels are facing the Y direction, the control unit directly calculates the second target speed and controls each motor to drive its connected drive wheels to rotate at the same speed, causing the mobile robot chassis to move linearly along the Y direction. If not all drive wheels are facing the Y direction, the control unit calculates the first target speed and controls the two drive wheels in the drive assembly whose orientation needs to be adjusted to rotate in opposite directions, causing the drive assembly to rotate in place until the drive wheels are facing the Y direction. The same target movement vector V is then input again. X =0、V y =V, ω=0, the camera captures an image to determine that all drive wheels are facing the Y direction at this time, the control unit calculates the second target speed, and controls the drive wheels to rotate at the same speed, so that the chassis of the mobile robot moves in a straight line along the Y direction.

[0069] Regarding stopping the rotation of the drive components, it can be done manually by inputting the stop signal, or it can be controlled in the same way as the differential steering wheel AGV. For example, a camera can be used to capture the orientation of the drive wheels in each drive component. When the orientation of the drive wheels rotates to be consistent with the target direction, the control unit receives the signal sent by the camera and controls the drive wheels to stop rotating.

[0070] Regarding stopping the movement of the mobile robot chassis, it can be done manually by inputting the stop signal, or it can autonomously determine the path based on an algorithm. Autonomous path determination requires cooperation with components such as the positioning system and radar. When the mobile robot chassis moves to the target position, the control unit receives the signal sent by the radar or positioning system and controls the drive wheels to stop rotating.

[0071] like Figure 5 As shown, Figure 5 A flowchart illustrating the mobile robot chassis control method provided in this application embodiment. Figure 3 , and the aforementioned Figure 1 Compared to the embodiment shown, the forward direction of the drive wheel in each drive assembly is tangent to the target circle, which is the circumcircle of a rectangle with the positions of the four drive assemblies as corner points. The method also includes the following step S105.

[0072] S105: Controls each motor to drive the connected drive wheel to rotate at the same speed, so that the mobile robot chassis spins in place.

[0073] like Figure 6 As shown, Figure 6 This is a schematic diagram of the motion of the mobile robot chassis spinning in place according to an embodiment of this application. The four drive components are arranged rotationally symmetrically, and the extension lines of the shafts of all drive wheels intersect at the rotation center O of the mobile robot chassis. The input target movement vector V X =0、V y =0, ω=ω, ω is not 0, calculate that the target speed of all drive wheels is equal, all motors rotate in the same direction at the same speed, drive all drive wheels to rotate in the same direction at the same speed, so that the chassis of the mobile robot spins in place around its own rotation center O.

[0074] like Figure 7 As shown, Figure 7 A flowchart illustrating the mobile robot chassis control method provided in this application embodiment. Figure 4 , and the aforementioned Figure 1 Compared to the illustrated embodiment, step S102 can be implemented by step S102A.

[0075] S102A: Input the target movement vector into the pre-trained rotational speed calculation model to obtain the rotational speed of each drive wheel output by the rotational speed calculation model.

[0076] The rotational speed calculation model can be a large-scale data model, trained by inputting a large number of moving vectors as samples to achieve the above functions. Since the rotational speed calculation model is trained based on a large number of moving vectors as samples, the results obtained using this model are more accurate.

[0077] like Figure 8 As shown, Figure 8 This is a schematic diagram of the structure of a mobile robot chassis according to an embodiment of this application. This application proposes a mobile robot chassis. Applying the method of any of the above embodiments, the mobile robot chassis includes a frame 100, four drive components 200, and a control unit (not shown in the figure). The four drive components 200 are symmetrically arranged on both sides of the frame 100. Each drive component 200 includes a connecting structure 210, two motors 220, and two drive wheels 230 of the same diameter. The two motors 220 are mounted on the connecting structure 210 and positioned between the two drive wheels 230, with each motor 220 connected to one drive wheel 230. The connecting structure 210 has a vertical rotating shaft 211 at its upper end, and the connecting structure 210 is rotatably connected to the frame 100 via the rotating shaft 211. The control unit can control the two motors 220 in the same drive component 200 to drive their connected drive wheels 230 to rotate in opposite directions, so that each drive component 200 rotates in place.

[0078] It should be noted that the two drive wheels 230 rotating in opposite directions means that one drive wheel 230 rotates clockwise and the other rotates counterclockwise; the rotation of each drive component 200 in place means that the drive component 200 rotates around the rotation axis 211 of the connecting structure 210.

[0079] The mobile robot chassis of this embodiment includes a frame 100, four drive components 200, and a control unit. Each drive component 200 includes a connecting structure 210, two motors 220, and two drive wheels 230. The connecting structure 210 has a vertical rotating shaft 211 at its upper end, and is rotatably connected to the frame 100 via the rotating shaft 211, allowing the drive components 200 to rotate relative to the frame 100. Each motor 220 is connected to one drive wheel 230, allowing each drive wheel 230 to rotate independently. The control unit can control two motors 220 in the same drive component 200 to drive their connected drive wheels 230 to rotate in opposite directions, causing each drive component 200 to rotate in place, thereby adjusting the orientation of the drive wheels 230 and thus adjusting the direction of movement of the mobile robot chassis, achieving omnidirectional movement of the mobile robot chassis. Furthermore, each drive wheel 230 of the mobile robot chassis in this embodiment is an active wheel, with each motor 220 controlling one drive wheel 230, resulting in higher motion precision.

[0080] Compared to the omnidirectional chassis with Mecanum wheel structure in related technologies, the mobile robot chassis of this application embodiment uses a combination of motor 220 and ordinary drive wheels, which is simpler in structure, lower in cost, quieter, less wear on the ground, and has a stronger load-bearing capacity. In addition, the mobile robot chassis of this application embodiment does not need to use omnidirectional wheels, and the diameter of ordinary drive wheels can be made larger, resulting in a more robust structure. It can easily overcome small obstacles and gaps, and its adaptability to uneven ground is far superior to that of omnidirectional wheels. It has better obstacle-crossing performance, and its rolling friction is dominant, avoiding the sliding friction of omnidirectional wheels, reducing ineffective energy consumption and mechanical wear. It has lower energy consumption and component wear, and higher stability and mobility.

[0081] Optionally, the control unit can be mounted on the frame 100; the control unit can be connected to the motor driver (not shown in the figure) via a cable, and the motor driver can be directly connected to the motor 220 or integrated into the motor 220; the drive wheel 230 can be a rubber-coated wheel.

[0082] In some embodiments of this application, such as Figure 8 As shown, the chassis 100 includes a chassis body 110 and four connecting parts 130. The chassis body 110 has four clearance spaces 120, each clearance space 120 accommodating a drive assembly 200. Each connecting part 130 is suspended above a clearance space 120 and rotatably connected to the top of a connection structure 210 of a drive assembly 200. This arrangement helps to lower the center of gravity of the mobile robot chassis, reducing the risk of the mobile robot chassis tipping over.

[0083] like Figure 8 As shown, the connecting part 130 can be a bracket, including an L-shaped horizontal bracket 131 and two vertical brackets 132 arranged in a straight line; the horizontal bracket 131 is rotatably connected to the rotating shaft 211 of the connecting structure 210, and the vertical brackets 132 support the horizontal bracket 131 and are fixedly connected to the frame body 110.

[0084] In some embodiments of this application, the control unit can control the drive wheels 230 to rotate at the same speed and all drive wheels 230 to move in the same direction, so that the mobile robot chassis moves in a straight line. This straight-line movement includes along... Figure 8 The diagram shows forward and backward movement in the X direction, lateral movement in the Y direction, and oblique movement at a certain angle to the X and Y directions. During linear movement, the axis of the drive wheel 230 is perpendicular to the direction of movement of the mobile robot chassis.

[0085] In some embodiments of this application, the control unit can control two drive wheels 230 in the same drive assembly 200 to rotate in opposite directions, so that the forward direction of the drive wheels 230 in the drive assembly 200 changes from a first direction to a second direction. By controlling the two drive wheels 230 in the same drive assembly 200 to rotate in opposite directions, the orientation of the two drive wheels 230 in each drive assembly 200 can be adjusted, thereby adjusting the travel direction of the mobile robot chassis. When the forward direction of all the drive wheels 230 is the first direction, the control unit can control the two drive wheels 230 in the same drive assembly 200 to rotate at the same speed, and the mobile robot chassis can move linearly along the first direction. When the forward direction of all the drive wheels 230 is the second direction, the control unit can control the two drive wheels 230 in the same drive assembly 200 to rotate at the same speed, and the mobile robot chassis can move linearly along the second direction. This achieves lateral translation of the mobile robot chassis, that is, it can move laterally without changing the orientation of the frame 100, resulting in better maneuverability.

[0086] In some embodiments of this application, such as Figure 9 As shown, Figure 9 This is a schematic diagram showing the position of the target circle C in this embodiment. The control unit can control the forward direction of the drive wheel 230 in the drive assembly 200 to be tangent to the target circle C, and control the drive wheel 230 to rotate at the same speed and direction, so that the chassis of the mobile robot can spin in place. The target circle C is a rectangle with the positions of the four drive assemblies 200 as corner points (e.g., ...). Figure 9 The circumcircle of the target circle C (shown as a dashed rectangle). When the forward direction of the drive wheel 230 is tangent to the target circle C and both rotate clockwise or counterclockwise, the mobile robot chassis can spin in place around its own rotation axis, with the center of the target circle C located on that rotation axis.

[0087] The mobile robot chassis of this application embodiment receives speed commands and controls the motor 220 to run at precise speed and torque. By precisely controlling the differential speed of the two drive wheels 230 of the same drive component 200, the desired movement vector is actively synthesized to achieve forward, backward, spin and translation in any direction. Translation in any direction includes lateral movement and diagonal movement, thus achieving omnidirectional motion.

[0088] In some embodiments of this application, such as Figure 10 and Figure 11 As shown, Figure 10 This is an isometric view of the drive component 200 in the embodiments of this application. Figure 11This is a side view of the drive assembly 200 in this embodiment. Two drive wheels 230 in the drive assembly 200 are coaxially arranged to ensure high motion accuracy. Motors 220 can be directly connected to the drive wheels 230, and the output terminals of the two motors 220 in the drive assembly 200 are coaxially arranged with the two drive wheels 230.

[0089] The mobile robot chassis of this application controls the rotational speed of the two drive wheels 230 of the same drive component 200 to synthesize a velocity vector in a two-dimensional plane at the wheel set center point A (Instantaneous Center of Rotation, ICR). The wheel set center point A is the intersection of the axis of the rotation axis 211 of the drive component 200 and the axis of the motor 220.

[0090] The two drive wheels 230 in the same drive assembly 200 have the same speed. The drive wheel 230 will generate a velocity vector on the ground, the direction of which is along the plane of the drive wheel 230. The planes of the two drive wheels 230 in the same drive assembly 200 are always parallel.

[0091] The two drive wheels 230 in the same drive assembly 200 have different speeds, and the drive wheels 230 will generate an angular velocity about their wheel set center point A. This rotational motion is superimposed on the overall translational motion of the drive assembly 200.

[0092] The actual speed of the wheel center point A is the vector sum of the two drive wheels 230 in the same drive component 200. By precisely controlling the speed of the two drive wheels 230, the magnitude and direction of the desired speed vector of the wheel center point A can be actively synthesized, enabling the mobile robot chassis to achieve omnidirectional movement.

[0093] The formula for calculating the center point A of the wheelset is as follows: ; ;

[0094] Where V is the velocity of the wheel center point A, ω is the rotational angular velocity of the wheel center point A, d is the distance between the outer surfaces of the two drive wheels 230, the outer surface of the drive wheel 230 refers to the surface of the drive wheel 230 away from the connecting structure 210 in the axial direction of the drive shaft 230, and V1 and V2 are the vector movement velocities of the two drive wheels 230 in the same drive assembly 200 on the horizontal plane.

[0095] In some embodiments of this application, such as Figure 12 As shown, Figure 12 This is an exploded view of the driving component 200 in the embodiments of this application. Figure 1Each connection structure 210 also includes a rigid bridge 212, the top of which is connected to the bottom of the rotating shaft 211, and the two sides of which are fixedly connected to two motors 220 respectively. The rigid bridge 212 is the core skeleton of the drive assembly 200, ensuring a rigid connection between the two motors 220, which is beneficial to improving motion accuracy. It can be a high-strength casting or a CNC (Computer Numerical Control) machined part.

[0096] like Figure 12 As shown, the rotating shaft 211 may include a connecting post 2111 and a connecting block 2112 connected together, the connecting post 2111 being connected to the frame ( Figure 12 (Not shown in the figure) can be rotatably connected by a bearing (not shown in the figure), and the connecting block 2112 is fixedly connected to the rigid bridge 212.

[0097] In some embodiments of this application, such as Figure 13 and Figure 14 As shown, Figure 13 This is a schematic diagram showing the location of the motor mounting part in an embodiment of this application. Figure 14 This is an exploded view of the driving component 200 in the embodiments of this application. Figure 2 The rigid bridge 212 has two motor mounting portions on both sides; each motor mounting portion has a groove 2121, the inner wall of which is adapted to the body of the motor 220. The body of each motor 220 is embedded in the groove 2121 of one motor mounting portion, and the center of the groove 2121 is located in the extension direction of the shaft of the output end of the motor 220 embedded therein. The motor mounting portions facilitate the quick installation and positioning of the motor 220, ensuring that the output ends of the two motors 220 in the same drive assembly 200 are coaxially arranged and located in the same horizontal plane, providing a precise motor 220 mounting position. While ensuring high motion accuracy, this reduces the occurrence of drive assembly 200 twisting and damage to the motor 220 output end due to additional radial force.

[0098] like Figure 14 As shown, the two motor mounting parts can be symmetrically arranged, with no gap between them and fixed connection. During the movement, the positions of the two motor mounting parts are relatively fixed to ensure that the distance between the two drive wheels 230 in the same drive assembly 200 is always equal during the movement, so as to achieve stable differential movement and ensure movement accuracy.

[0099] like Figure 14 As shown, the rigid cable tray 212 also includes a mounting flange 2122. The lower end of the mounting flange 2122 is fixedly connected to the motor mounting part, and the upper end of the mounting flange 2122 is connected to the rotating shaft 211.

[0100] In some embodiments of this application, such as Figure 14 As shown, an output shaft 213, a bearing washer 214, a crossed roller bearing 215, a bearing cover plate 216, and a bearing bracket 217 may be provided between the motor 220 and the drive wheel 230.

[0101] like Figure 15 and Figure 16 As shown, Figure 15 This is a schematic diagram of the drive assembly 200 in this embodiment of the application, omitting one drive wheel 230. Figure 16 This is a cross-sectional view of the drive assembly 200 in this embodiment. The bearing bracket 217 is annular and is fitted around the output end of the motor 220, and is fixedly connected to the motor 220 body. The crossed roller bearing 215 is fitted around the output end of the motor 220, located between the output end of the motor 220 and the bearing bracket 217. The inner ring of the crossed roller bearing 215 is connected to the output end of the motor 220, and the outer ring is connected to the bearing bracket 217 to reduce friction. The bearing cover plate 216 is annular and is disposed on the outer end face of the bearing bracket 217. The two are fixedly connected, and the bearing cover plate 216 abuts against the outer end face of the crossed roller bearing 215 to resist friction. The roller bearing 215 is used for positioning; the output end of the motor 220 is fixedly connected to the output shaft 213, and the output shaft 213 is fixedly connected to the drive wheel 230; the bearing washer 214 is sleeved on the outside of the output shaft 213 and located between the drive wheel 230 and the crossed roller bearing 215. The inner side of the bearing washer 214 abuts against the outer end face of the crossed roller bearing 215, and the outer side abuts against the inner side of the drive wheel 230 to fix the crossed roller bearing 215. By controlling the thickness of the bearing washer 214, the axial clearance at the end of the crossed roller bearing 215 can be precisely adjusted to ensure the stability of the equipment during operation; the above-mentioned fixed connection method can be a fastener fixed connection.

[0102] In some embodiments of this application, each connection structure 210 further includes a shock absorber (not shown in the figure); the shock absorber is sleeved on the outside of the rotating shaft 211 and located between the rotating shaft 211 and the frame 100. The shock absorber can provide damping force to absorb the kinetic energy generated when the drive wheel 230 swings up and down, avoid the impact being directly transmitted to the frame 100, and prevent the rotating shaft 211 from oscillating excessively.

[0103] like Figure 16 As shown, the connecting column 2111 of the rotating shaft 211 can have a stepped structure. The damping element is sleeved on the connecting column 2111, with the lower end of the damping element abutting against the stepped surface of the stepped structure and the upper end against... Figure 8 The lower ends of the horizontal bracket 131 of the connecting part 130 shown abut against each other.

[0104] Alternatively, the shock absorber can be a polyurethane cushioning pad or an air spring.

[0105] In some embodiments of this application, the mobile robot chassis also includes sensors (not shown in the figures); the sensors are mounted on the frame 100 and are capable of obstacle detection, in order to cooperate with the control unit to control the movement of the mobile robot chassis.

[0106] Optionally, the sensor may include a camera and / or radar, etc.

[0107] like Figure 17 As shown, Figure 17 This is a schematic diagram of the structure of a mobile robot provided in an embodiment of this application. This application proposes a mobile robot including a mobile robot chassis, a processor 401, and a memory 402, as described in any of the above embodiments. The memory 402 is used to store executable instructions; the processor 401 is used to execute the executable instructions stored in the memory to implement the steps included in the mobile robot chassis control method described above.

[0108] The mobile robot also includes a communication bus 403, through which the processor 401 and the memory 402 communicate with each other.

[0109] In one possible implementation, the mobile robot may further include a communication interface 404, and the communication interface 404 communicates with the processor 401 and the memory 402 via a communication bus 403. The mobile robot can transmit data with external devices through the communication interface 404.

[0110] In practical applications, the omnidirectional motion of the mobile robot chassis enables the mobile robot to move in all directions. Furthermore, each drive wheel 230 of the mobile robot chassis is an active wheel, and each motor 220 controls one drive wheel 230, resulting in higher motion precision.

[0111] The mobile robot chassis of this application embodiment can be applied to outdoor inspection robots, heavy-duty AGVs (Automated Guided Vehicles), service robots, agricultural robots, and intelligent home mobile platforms.

[0112] Among them, the outdoor inspection robot can be used for power plant and factory area inspections. The robot needs to move stably on cement roads, grass, and gravel roads. The mobile robot chassis of this application embodiment can effectively cope with complex outdoor road conditions, maintain the stability of the body, and ensure that the collected images and data are clear and stable.

[0113] Heavy-duty AGVs refer to AGVs capable of carrying hundreds of kilograms to several tons of weight, which can cause bumps when traveling on warehouse floor joints or tracks. The shock-absorbing components of the mobile robot chassis in this application are designed to protect the carried goods from vibration damage, while significantly improving the fatigue life of the AGV's mechanical structure.

[0114] Service robots can be used for restaurant food delivery, hotel guidance, and hospital supply transportation, requiring flexible obstacle avoidance and smooth movement in densely populated environments. The mobile robot chassis in this embodiment exhibits smooth translational movement, avoiding sharp turns, and its omnidirectional mobility allows it to maneuver easily in crowded spaces, enhancing the user experience.

[0115] Agricultural robots can perform tasks such as sowing, fertilizing, and harvesting. The mobile robot chassis of this application has excellent terrain adaptability, which ensures the stability of the working platform, enabling the robotic arm and other actuators to work accurately, while reducing damage to the agricultural robot caused by vibration.

[0116] A smart home mobile platform can serve as a multi-functional, universal mobile chassis within the home, requiring quiet and stable movement across thresholds and carpet edges between rooms. The mobile robot chassis of this application embodiment exhibits stable movement and excellent shock absorption performance, making it suitable for this application scenario.

[0117] As an example, processor 401 may be a processor in the form of a hardware-decoded processor, which is programmed to execute the mobile robot chassis control method provided in the embodiments of this application. For example, the processor in the form of a hardware-decoded processor may employ one or more application-specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), complex programmable logic devices (CPLDs), field-programmable gate arrays (FPGAs), or other electronic components.

[0118] like Figure 18 As shown, Figure 18This is a schematic diagram of a mobile robot chassis control device provided in an embodiment of this application. The embodiment proposes a mobile robot chassis control device applied to a control unit in a mobile robot chassis. The mobile robot chassis also includes a frame and four drive components, which are symmetrically arranged on both sides of the frame. Each drive component includes a connecting structure, two motors, and two drive wheels of the same diameter, with each motor connected to one drive wheel. The connecting structure is rotatably connected to the frame. The device includes a vector receiving module 301, a rotational speed calculation module 302, and a first control module 303. The vector receiving module 301 receives a target movement vector, which includes a first speed to be moved along a first direction, a second speed to be moved along a second direction, and a stationary spin angular velocity. The first direction and the second direction are horizontally perpendicular. The rotational speed calculation module 302 calculates the rotational speed of each drive wheel based on the target movement vector. The first control module 303 controls the drive component to rotate in place when two motors in the same drive component drive their connected drive wheels to rotate in opposite directions.

[0119] The mobile robot chassis control device of this application embodiment controls each motor to drive the connected drive wheel to rotate at its corresponding speed. When two drive wheels in the same drive assembly rotate in opposite directions, the drive assembly rotates in place, thereby adjusting the orientation of the drive wheels to adjust the movement direction of the mobile robot chassis and controlling the mobile robot chassis to perform omnidirectional movement. Moreover, each drive wheel can be controlled independently, resulting in higher movement accuracy.

[0120] In some embodiments of this application, the device further includes a second control module, which controls each motor to drive the connected drive wheel to rotate at the same speed when the drive wheels are moving in the same direction, so that the mobile robot chassis moves in a straight line.

[0121] Linear motion includes the forward, backward, translational, and diagonal movements of the mobile robot chassis.

[0122] All drive wheels and motor output shafts extend along the Y direction. The second control module controls all motors to rotate in the same direction at the same speed, driving all drive wheels to rotate in the same direction at the same speed, so that the mobile robot chassis moves forward or backward in the X direction.

[0123] The shafts of all drive wheels and the output shafts of the motors extend along the X direction. The second control module controls all motors to rotate in the same direction at the same speed, which drives all drive wheels to rotate in the same direction at the same speed, causing the mobile robot chassis to move laterally in the Y direction.

[0124] All drive wheels and motor output shafts extend along a third direction, which forms a certain angle with the X and Y directions. The second control module controls all motors to rotate in the same direction at the same speed, driving all drive wheels to rotate in the same direction at the same speed, thus causing the mobile robot chassis to move obliquely.

[0125] In some embodiments of this application, the device further includes a third control module, which is used to control each motor to drive the connected drive wheel to rotate at the same speed when the forward direction of the drive wheel in each drive component is tangent to the target circle, and the target circle is the circumcircle of a rectangle with the positions of the four drive components as corner points, so that the chassis of the mobile robot spins in place.

[0126] The four drive components are arranged in a rotational symmetry, and the extension lines of the shafts of all the drive wheels intersect at the rotation center of the mobile robot chassis. The third control module controls all the motors to rotate in the same direction at the same speed, which drives all the drive wheels to rotate in the same direction at the same speed, so that the mobile robot chassis spins in place around its own rotation center.

[0127] In some embodiments of this application, the rotational speed calculation module 302 is specifically used to input the target movement vector into a pre-trained rotational speed calculation model to obtain the rotational speed of each drive wheel output by the rotational speed calculation model.

[0128] The rotational speed calculation model can be a large-scale data model, trained by inputting a large number of moving vectors as samples to achieve the above functions. Since the rotational speed calculation model is trained based on a large number of moving vectors as samples, the results obtained using this model are more accurate.

[0129] It should be noted that the description of the device embodiments in this application is similar to the description of the method embodiments described above, and has similar beneficial effects as the method embodiments; therefore, it will not be repeated. For technical details not disclosed in the device embodiments, please refer to the description of the method embodiments in this application for understanding.

[0130] This application provides a computer-readable storage medium storing a computer program, which, when executed by processor 401, implements the method steps of any of the above embodiments.

[0131] The computer-readable storage medium of this application embodiment stores a computer program. When the computer program is executed by the processor 401, it implements the method steps of any of the above embodiments. The method steps control each motor to drive the connected drive wheel to rotate at its corresponding speed. When two drive wheels in the same drive assembly rotate in opposite directions, the drive assembly rotates in place, thereby adjusting the orientation of the drive wheels to adjust the movement direction of the mobile robot chassis and controlling the mobile robot chassis to perform omnidirectional movement. Moreover, each drive wheel can be controlled independently, resulting in higher movement accuracy.

[0132] This application provides a computer program product containing instructions that, when run on a computer, cause the computer to perform the method steps of any of the above embodiments.

[0133] The computer program product containing instructions in this application embodiment, when run on a computer, causes the computer to execute the method steps of any of the above embodiments. Through the above method steps, each motor drives the connected drive wheel to rotate at its corresponding speed. When two drive wheels in the same drive assembly rotate in opposite directions, the drive assembly rotates in place, thereby adjusting the orientation of the drive wheels to adjust the movement direction of the mobile robot chassis and controlling the mobile robot chassis to perform omnidirectional movement. Moreover, each drive wheel can be controlled independently, resulting in higher movement precision.

[0134] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially as a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid state disk (SSD)).

[0135] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0136] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the embodiments for mobile robots, devices, computer-readable storage media, and computer program products are basically similar to the method embodiments, so the descriptions are relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0137] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A method for controlling the chassis of a mobile robot, characterized in that, The control unit is applied in the mobile robot chassis, which also includes a frame and four drive components. The four drive components are symmetrically arranged on both sides of the frame. Each drive component includes a connection structure, two motors, and two drive wheels of the same diameter, with each motor connected to one drive wheel. The connecting structure is rotatably connected to the vehicle frame; The method includes: Receive a target movement vector, the target movement vector including: a first speed to be moved along a first direction, a second speed to be moved along a second direction, and a spin angular velocity in place, wherein the first direction and the second direction are horizontally perpendicular; Based on the target movement vector, determine the rotational speed of each drive wheel; When two motors in the same drive assembly drive the connected drive wheels to rotate in opposite directions, the drive assembly rotates in place.

2. The method according to claim 1, characterized in that, When the driving wheels are moving in the same direction, the method further includes: controlling each motor to drive the connected driving wheels to rotate at the same speed, so that the mobile robot chassis moves in a straight line; And / or, The forward direction of the drive wheel in each drive assembly is tangent to the target circle, which is the circumcircle of a rectangle with the positions of the four drive assemblies as corner points. The method further includes controlling each motor to drive the connected drive wheel to rotate at the same speed, so that the mobile robot chassis spins in place.

3. The method according to claim 1 or 2, characterized in that, The step of calculating the rotational speed of each drive wheel based on the target movement vector includes: The target movement vector is input into a pre-trained rotational speed calculation model to obtain the rotational speed of each drive wheel output by the rotational speed calculation model.

4. A mobile robot chassis, characterized in that, The mobile robot chassis, using the method of any one of claims 1 to 3, comprises: Frame (100); Four drive assemblies (200) are symmetrically arranged on both sides of the frame (100). Each drive assembly (200) includes a connecting structure (210), two motors (220), and two drive wheels (230) of the same diameter. The two motors (220) are mounted on the connecting structure (210) and positioned between the two drive wheels (230). Each motor (220) is connected to one drive wheel (230). The connecting structure (210) has a vertical rotating shaft (211) at its upper end, and the connecting structure (210) is rotatably connected to the frame (100) through the rotating shaft (211). The control unit is capable of controlling two motors (220) in the same drive assembly (200) to drive their connected drive wheels (230) to rotate in opposite directions, so that each of the drive assemblies (200) rotates in place.

5. The mobile robot chassis according to claim 4, characterized in that, The control unit can control the drive wheels (230) to rotate at the same speed and all the drive wheels (230) to move in the same direction, so that the chassis of the mobile robot moves in a straight line; And / or, The control unit can control two drive wheels (230) in the same drive assembly (200) to rotate in opposite directions, so that the forward direction of the drive wheels (230) in the drive assembly (200) is changed from the first direction to the second direction; And / or, The control unit can control the forward direction of the drive wheel (230) in the drive assembly (200) to be tangent to the target circle (C), and control the drive wheel (230) to rotate at the same speed and direction so that the chassis of the mobile robot can spin in place. The target circle (C) is the circumcircle of the rectangle with the positions of the four drive assemblies (200) as corner points.

6. The mobile robot chassis according to claim 4 or 5, characterized in that, The two drive wheels (230) in the drive assembly (200) are coaxially arranged.

7. A mobile robot, characterized in that, The mobile robot includes a mobile robot chassis as described in any one of claims 4 to 6, and the mobile robot further includes: Memory, used to store executable instructions; A processor, when executing executable instructions stored in the memory, implements the method steps as described in any one of claims 1 to 3.

8. A mobile robot chassis control device, characterized in that, The control unit is applied in the mobile robot chassis, which also includes a frame and four drive components. The four drive components are symmetrically arranged on both sides of the frame. Each drive component includes a connection structure, two motors, and two drive wheels of the same diameter, with each motor connected to one drive wheel. The connecting structure is rotatably connected to the vehicle frame; The device includes: A vector receiving module is used to receive a target movement vector, the target movement vector including: a first speed to be moved along a first direction, a second speed to be moved along a second direction, and a spin angular velocity in place of the mobile robot chassis, wherein the first direction and the second direction are horizontally perpendicular; The rotational speed calculation module is used to calculate the rotational speed of each drive wheel based on the target movement vector. The first control module is used to control the drive assembly to rotate in place when the two motors in the same drive assembly drive the connected drive wheels to rotate in opposite directions.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the method described in any one of claims 1 to 3.

10. A computer program product containing instructions, characterized in that, When it is run on a computer, it causes the computer to perform the steps of the method described in any one of claims 1 to 3.

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