2WIS omnidirectional wheel device and control algorithm

Abstract

The invention discloses a 2WIS omnidirectional wheel device and a control algorithm, and relates to the technical field of mechanical engineering and automatic control. The two driving wheels are symmetrically distributed on the two sides of the rack in the horizontal direction, and the rotating axes of the driving wheels extend horizontally. The two driving wheels are both provided with support assemblies, each support assembly comprises a steering support, a first driving mechanism and a second driving mechanism, one end of each steering support is rotationally installed on the rack, the rotating axis of each steering support extends vertically, and each steering support is provided with the corresponding first driving mechanism for driving the corresponding steering support to rotate in a matched mode. A second driving mechanism for driving the driving wheel to rotate is mounted at the other end of the steering bracket; the driven wheel is rotatably mounted on the rack and is supported on the ground together with the two driving wheels, so that the manufacturing cost is effectively reduced, continuous and any-angle steering control is ensured to be realized, and the steering device can be applied to the fields of automatic driving vehicles, robots, intelligent carriers and the like, in particular to occasions requiring high-precision control and flexible steering.

Description

Technical Field

[0001] The present invention relates to the technical fields of mechanical engineering and automation control, and particularly relates to a 2WIS omnidirectional wheel device and a control algorithm. Background Art

[0002] Traditional omnidirectional wheel structures are widely used in devices such as robots and autonomous driving platforms to achieve smooth steering control. However, there are certain limitations in the design of omnidirectional wheels. Especially under complex steering conditions, it may lead to low motion accuracy or unstable control.

[0003] For omnidirectional wheels based on Mecanum wheels, the characteristic of Mecanum wheels is that multiple rollers with an installation angle of 45 degrees (usually 4 rollers) are installed on each wheel, and the inclination angle of each roller helps it provide thrust in multiple directions. With four rollers placed at the four corners of the robot respectively, it can achieve translation, rotation, and combined movement in any direction, and the control is relatively intuitive. By differentially controlling the speed and direction of the four rollers, movement in any direction can be achieved. Compared with traditional wheels, it does not require an additional steering mechanism to change the direction, simplifying the design.

[0004] However, due to the installation angle and design of the rollers, the friction and traction are not as good as those of traditional wheels. And it has high requirements for ground flatness and requires regular replacement of worn parts. Once the ground is uneven, the force decomposition strategy fails and omnidirectional movement cannot be achieved. At the same time, each roller has a complex angle design, the manufacturing process is relatively complex and difficult to maintain. And due to the complex structure, the load-bearing capacity is generally not as good as that of traditional wheels.

[0005] The differential wheel system, as a common driving method, is widely used in differential drive type devices. Although it can provide good linear motion and steering control, its traditional steering method usually requires additional devices to achieve more flexible manipulation. Taking the omnidirectional wheel mainly based on 4WIS as an example, its system usually consists of four independently steerable rollers, and each roller can independently adjust its steering angle, enabling the robot to translate, rotate, or perform combined movements in any direction. This design is different from that of Mecanum wheels. 4WIS relies on the individual steering of each roller to achieve omnidirectional control, rather than through the inclination angle. As Figure 1 shown, this type of differential wheel supports various modes such as lateral movement, diagonal movement, single Ackermann movement, double Ackermann movement, diagonal Ackermann movement, and in-situ spin. The independent steering of each roller provides higher control accuracy and flexibility, and can achieve more precise motion control, especially in narrow spaces. And since the steering of each roller is completely independent, the system can achieve smooth omnidirectional movement. At the same time, each roller can be individually controlled, so the load-bearing capacity is usually stronger and it is suitable for heavier loads.

[0006] However, since the 4WIS system requires independent drive and steering mechanisms, the complexity of design and control is increased. Multiple independent steering mechanisms require more drive mechanisms and control systems, so the energy consumption is relatively high. And the system requires a sophisticated control strategy to coordinate the steering and drive of the four rollers, which increases the complexity of the control system. Therefore, how to achieve a lower-cost omnidirectional wheel control system while maintaining the advantages of the 4WIS system is a technology that needs to be solved in industrial production. Summary of the invention

[0007] The purpose of the present invention is to provide a 2WIS omnidirectional wheel device and a control algorithm to solve the problems existing in the above-mentioned prior art, which can effectively reduce the production cost and ensure continuous and arbitrary angle steering control. It can be widely used in the fields of autonomous driving vehicles, robots, intelligent transport vehicles, etc., especially in situations requiring high-precision control and flexible steering.

[0008] To achieve the above object, the present invention provides the following solution: The present invention provides a 2WIS omnidirectional wheel device, comprising a frame, two independently arranged driving wheels, and at least one driven wheel;

[0009] The two driving wheels are symmetrically distributed on both sides of the frame in the horizontal direction, and the rotation axes of the driving wheels extend horizontally;

[0010] Both driving wheels are equipped with a bracket assembly, which includes a steering bracket, a first driving mechanism and a second driving mechanism. One end of the steering bracket is rotatably mounted on the frame, and its rotation axis extends vertically, and is equipped with a first driving mechanism to drive its rotation. The other end of the steering bracket is equipped with a second driving mechanism to drive the driving wheel to rotate.

[0011] The driven wheel is rotatably mounted on the frame and is supported on the ground together with the two driving wheels.

[0012] Preferably, a conductive slip ring is provided between the end of each steering bracket where the second driving mechanism is not installed and the frame, and the conductive slip ring includes a stator and a rotor;

[0013] The stator is mounted on the frame and is used to be electrically connected to the main control mechanism;

[0014] The rotor is mounted on the steering bracket and is transmission-connected to the first drive mechanism, and its rotation axis extends vertically. The rotor rotates synchronously with the steering bracket, and the wires led out from the rotor are electrically connected to the second drive mechanism.

[0015] Preferably, two steering actuators respectively corresponding to and connected to the steering brackets are rotatably mounted on the frame. The rotation axes of the steering actuators extend vertically, and mounting channels are coaxially formed through the steering actuators.

[0016] The conductive slip ring is embedded in the mounting channel. The outer ring of the conductive slip ring is the rotor and is fixedly connected to the steering actuator, and the inner ring of the conductive slip ring is the stator and is fixedly connected to the frame.

[0017] Preferably, the first driving mechanism is in transmission connection with the steering actuator and drives the steering actuator to rotate.

[0018] Preferably, the first driving mechanism is a driving motor, and the driving motor is provided with a hollow motor shaft serving as the steering actuator.

[0019] Preferably, the driving wheel includes a wheel hub and a tire. The tire is mounted on the rim of the wheel hub, and the second driving mechanism is in transmission connection with the wheel hub.

[0020] Preferably, the second driving mechanism adopts a hub motor, and the hub motor is built in the inner peripheral side of the wheel hub.

[0021] Preferably, two driven wheels are mounted on the frame. The two driven wheels are located between the two driving wheels along the arrangement direction of the two driving wheels and are distributed on both sides of the frame along the direction perpendicular to the arrangement of the two driving wheels.

[0022] Preferably, the driven wheels adopt universal wheels.

[0023] A control algorithm for a 2WIS omnidirectional wheel device is further provided. Based on the V / W decomposition method, V and W respectively represent the linear velocity and angular velocity of the 2WIS omnidirectional wheel device itself.

[0024] Among them, the linear velocity V = (V x , V y ) T ; the angular velocity

[0025] The position formula of the velocity instantaneous center of the 2WIS omnidirectional wheel device is: x ICR = V y / Wz, y ICR = V x / Wz;

[0026] The linear velocity of each driving wheel is obtained through the geometric relationship between the instantaneous center position and the driving wheel. The linear velocity of the i-th driving wheel can be calculated by the following formula:

[0027] Denote the instant center of velocity as I. Then, the vector from the instant center of velocity to the center of the first driving wheel (the blue part in the above figure) is:

[0028]

[0029] Among them, is the connecting vector from the center point of the 2WIS omnidirectional wheel device itself to the rotation center of the first driving wheel. is the vector from the center point of the 2WIS omnidirectional wheel device itself to the instant center of velocity ICR. Subtracting the vectors gives the vector from the rotation center of the first driving wheel DE to the instant center of velocity, which is used as the velocity decomposition radius. The position of the first driving wheel is C1(x1, y1).

[0030] Then, the linear velocity at the first driving wheel should be:

[0031]

[0032] Among them, X is the outer product of vectors, cross product.

[0033] Then, the magnitude of the expected linear velocity at the first driving wheel is:

[0034]

[0035] Similarly, the linear velocity at the second driving wheel can be expressed as a general formula:

[0036]

[0037] Convert the linear velocity of the driving wheel i into the angular velocity of the driving wheel i, where R is the radius of the in-wheel motor:

[0038]

[0039] Correspondingly, the steering angle of the driving wheel is:

[0040]

[0041] For any After obtaining the control commands for each wheel leg using the above formula, each in-wheel motor is in the speed loop mode and the speed command is:

[0042]

[0043] The steering motor of each leg is in the position loop mode and the steering angle:

[0044]

[0045] For different motion modes, control the value.

[0046] The present invention has achieved the following technical effects compared with the prior art:

[0047] Based on the differential wheel, the present invention provides basic differential drive control by setting two independent drive wheels, driving the corresponding steering brackets and drive wheels to turn through each first drive mechanism, driving the corresponding drive wheels to move forward through the second drive mechanism, and then controlling the speed difference between the two drive wheels. The two drive wheels can achieve continuous linear velocity and angular velocity commands in a two-dimensional plane and steering operations at any angle. Compared with the 4WIS system, it reduces half of the drive mechanisms, can effectively reduce the manufacturing cost, and has higher stability and controllability compared with the universal wheel structure, solving the problem of insufficient flexibility of traditional universal wheels in complex steering processes. It can be widely applied to fields such as autonomous vehicles, robots, intelligent transport vehicles, etc., especially in occasions that require high-precision control and flexible steering. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0049] Figure 1 It is a schematic diagram of 4WIS speed command decomposition and mode in the prior art;

[0050] Figure 2 It is a speed command decomposition diagram of the present invention;

[0051] Figure 3 It is a schematic diagram of the decomposition vector of the instantaneous center of rotation ICR of the present invention;

[0052] Figure 4 It is a schematic diagram of each motion mode of the entire device of the present invention;

[0053] Figure 5 It is a schematic diagram of the overall structure of the entire device of the present invention Figure 1 ;

[0054] Figure 6 It is a schematic diagram of the overall structure of the entire device of the present invention Figure 2 ;

[0055] Figure 7 It is an enlarged view of the connection between the steering bracket and the frame of the present invention;

[0056] Among them, 1 - upper cover plate, 2 - column, 3 - steering bracket, 4 - lower cover plate, 5 - driven wheel, 6 - steering actuator, 7 - driving wheel, 8 - in-wheel motor, 9 - conductive slip ring. Specific embodiments

[0057] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0058] The purpose of the present invention is to provide a 2WIS omnidirectional wheel device and a control algorithm to solve the problems existing in the above-mentioned prior art, which can effectively reduce the manufacturing cost and ensure continuous and arbitrary-angle steering control, and can be widely applied to fields such as autonomous driving vehicles, robots, intelligent transport vehicles, etc., especially in occasions that require high-precision control and flexible steering.

[0059] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0060] Such as Figures 1 to 7As shown, this embodiment provides a 2WIS omnidirectional wheel device, including a frame, two independently arranged driving wheels 7, and at least one driven wheel 5; the two driving wheels 7 are symmetrically distributed on both sides of the frame in the horizontal direction, and the rotation axis of the driving wheels 7 extends horizontally; the two driving wheels 7 are equipped with a bracket assembly, and the bracket assembly includes a steering bracket 3, a first driving mechanism, and a second driving mechanism. One end of the steering bracket 3 is rotatably mounted on the frame, and its rotation axis extends vertically, and is equipped with a first driving mechanism that drives it to rotate. The first driving mechanism can adjust the rotation angle of the driving wheel 7 to ensure the accuracy of steering. The other end of the steering bracket 3 is equipped with a second driving mechanism that drives the driving wheel 7 to rotate; the driven wheel 5 is rotatably mounted on the frame and supported on the ground together with the two driving wheels 7, so as to provide a support point through the driven wheel 5, thereby improving the stability of the entire 2WIS omnidirectional wheel device. In addition, a main control mechanism is provided on the frame, which is responsible for monitoring and adjusting the coordinated work of the differential drive and the driving wheel 7 to ensure the stability and flexibility of the entire 2WIS omnidirectional wheel device. The present invention provides two independent driving wheels 7 on the basis of differential wheels, drives the corresponding steering bracket 3 and driving wheel 7 to steer through each first driving mechanism, drives the corresponding driving wheel 7 to move forward through the second driving mechanism, and then provides basic differential driving control by controlling the speed difference of the two driving wheels 7. The two driving wheels 7 can realize continuous linear velocity and angular velocity instructions in a two-dimensional plane and steering operations at any angle. Compared with the 4WIS system, the driving mechanism is reduced by half, which can effectively reduce the production cost. Compared with the universal wheel structure, it has higher stability and controllability, and solves the problem of insufficient flexibility of traditional universal wheels in complex steering processes. It can be widely used in the fields of autonomous driving vehicles, robots, intelligent transport vehicles, etc., especially in occasions requiring high-precision control and flexible steering.

[0061] In a specific embodiment, a conductive slip ring 9 is provided between the end of each steering bracket 3 where the second drive mechanism is not installed and the frame, and the conductive slip ring 9 includes a stator and a rotor; the stator is installed on the frame and is used to be electrically connected to the main control mechanism; the rotor is installed on the steering bracket 3 and is transmission-connected to the first drive mechanism, and its rotation axis extends vertically, the rotor rotates synchronously with the steering bracket 3, and the wire led out of the rotor is electrically connected to the second drive mechanism. By providing the conductive slip ring 9, it is ensured that the drive wheel 7 can still transmit power and signals when turning 360°.

[0062] In a specific embodiment, two steering actuators 6 respectively connected to the steering brackets 3 are rotatably mounted on the frame, the rotation axis of the steering actuator 6 extends vertically, and a mounting channel is coaxially penetrated on the steering actuator 6; the conductive slip ring 9 is embedded in the mounting channel, the outer ring of the conductive slip ring 9 is a rotor, and is fixedly connected to the steering actuator 6, and the rotor of the conductive slip ring 9 leads out a wire, and is electrically connected to the second drive mechanism through the lead-out wire. Since the steering bracket 3 and the rotor rotate synchronously with the steering actuator 6, there is no relative displacement between the steering bracket 3 and the rotor, and thus when the lead-out wire is electrically connected to the second drive mechanism, the stability of the connection can be ensured not to be affected by the rotation, the inner ring of the conductive slip ring 9 is a stator, and is fixedly connected to the frame, and by setting the steering actuator 6, it is possible to ensure the rotation coordination between the steering bracket 3 and the frame, and to complete the installation of the conductive slip ring 9, and use the conductive slip ring 9 to electrically connect the main control mechanism and the second drive mechanism. And as a preferred embodiment, a wire channel is opened in the steering bracket 3, so that the lead-out wire passes through the wire channel and is electrically connected to the second drive mechanism, thereby reducing the exposed wire.

[0063] In this embodiment, preferably, the first drive mechanism is connected to the steering actuator 6 and drives the steering actuator 6 to rotate. The steering actuator 6 is driven to rotate by the first drive mechanism, so that the steering actuator 6 can drive the rotor of the conductive slip ring 9, the steering bracket 3 and the driving wheel 7 to rotate synchronously, so as to complete the steering work of the driving wheel 7, and ensure that the electrical connection stability between the steering bracket 3 and the second drive mechanism and the rotor of the conductive slip ring 9 is maintained during the rotation.

[0064] In the present embodiment, as another preferred embodiment, the first driving mechanism is a driving motor, and the driving motor is provided with a hollow motor shaft as a steering actuator 6, which is directly connected to the steering bracket 3 through the hollow motor shaft to drive the steering bracket 3 and the driving wheel 7 to rotate synchronously, so as to be able to directly complete the steering work, and the conductive slip ring 9 is embedded in the hollow motor shaft, and the rotor of the conductive slip ring 9 rotates synchronously with the hollow motor shaft, and the rotor rotates synchronously with the second driving mechanism, and the two are connected by a wire, so that the connection structure between the steering bracket 3 and the frame is simpler, and the manufacturing cost is fully reduced.

[0065] In a specific embodiment, the driving wheel 7 includes a wheel hub and a tire, the tire is mounted on the rim of the wheel hub, and the second driving mechanism is connected to the wheel hub to drive the wheel hub and the tire to rotate. Preferably, the second driving mechanism uses a wheel hub motor 8, which is built into the inner circumference of the wheel hub, and the wheel hub motor 8 is driven by a high-resolution planetary reduction motor, which does not require mechanical structures such as a clutch, a gearbox, a transmission shaft, and a differential, thereby reducing the loss in energy transmission, simplifying the structure, reducing the failure points, and making maintenance more convenient.

[0066] In a specific embodiment, two driven wheels 5 are installed on the frame. Preferably, the driven wheels 5 are universal wheels. The two driven wheels 5 are located between the two driving wheels 7 along the arrangement direction of the two driving wheels 7, and are distributed on both sides of the frame along the direction perpendicular to the arrangement of the two driving wheels 7, forming a four-point support to ensure the stability of the whole device during the traveling process. Further preferably, only a single driven wheel 5 can be provided on the frame, and the driven wheel 5 and the two driving wheels 7 are distributed in an equilateral triangle, forming a three-point support. Further, the frame includes an upper cover plate 1, a lower cover plate 4, and a plurality of columns 2 connected between the upper cover plate 1 and the lower cover plate 4. The upper cover plate 1 and the lower cover plate 4 are spaced apart in the vertical direction, and the columns 2 are equally spaced along the circumferential direction of the upper cover plate 1 and the lower cover plate 4. The steering actuator 6, the steering bracket 3, etc. are all installed on the upper cover plate 1. An installation notch for accommodating structures such as the steering bracket 3 and the driving wheel 7 is formed on the outer peripheral edge of the lower cover plate 4. The driving wheel 7 passes through the installation notch and supports on the ground, and each driven wheel 5 is installed on the lower cover plate 4.

[0067] Furthermore, a control algorithm for a 2WIS omnidirectional wheel device is provided, based on the V / W decomposition method, where V and W respectively represent the linear velocity and angular velocity of the 2WIS omnidirectional wheel device itself;

[0068] Among them, the linear velocity V = (V x , V y ) T ; the angular velocity

[0069] The position formula of the velocity instant center of the 2WIS omnidirectional wheel device is: x ICR = V y / Wz, y ICR = V x / Wz;

[0070] The linear velocity of each driving wheel is obtained through the geometric relationship between the instant center position and the driving wheel. The linear velocity of the i-th driving wheel can be calculated by the following formula:

[0071] Denote the velocity instant center as I, then the vector from the velocity instant center to the center of the first driving wheel (the blue part in the above figure) is:

[0072]

[0073] Among them, is the connection vector from the center point (base) of the 2WIS omnidirectional wheel device itself to the rotation center of the first driving wheel, is the vector from the center point of the 2WIS omnidirectional wheel device itself to the velocity instant center ICR. Subtracting the vectors gives the vector from the rotation center of the first driving wheel DE to the velocity instant center, which is used as the velocity decomposition radius; the position of the first driving wheel is C1(x1, y1);

[0074] The linear velocity at the first driving wheel should be:

[0075]

[0076] where X is the cross product of vectors, a cross multiplication;

[0077] Then the magnitude of the expected linear velocity at the first driving wheel is:

[0078]

[0079] Similarly, the linear velocity at the second driving wheel can be expressed as a general formula:

[0080]

[0081] Convert the linear velocity of driving wheel i into the angular velocity of driving wheel i, where R is the radius of the in-wheel motor:

[0082]

[0083] Correspondingly, the steering angle of the driving wheel is:

[0084]

[0085] For any After obtaining the control instructions for each wheel leg using the above formula, each in-wheel motor is in the speed loop mode and the speed command is:

[0086]

[0087] The steering motor of each leg is in the position loop mode and the steering angle:

[0088]

[0089] For different motion modes, control the value of.

[0090] Among them, different speed and angular velocity commands correspond to different motion modes as shown in Table 1.

[0091]

[0092] Table 1

[0093] All adaptive changes made according to actual needs are within the protection scope of the present invention.

[0094] It should be noted that for those skilled in the art, it is obvious that the present invention is not limited to the details of the above-described exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be construed as limiting the claims involved.

[0095] Specific examples are used in the present invention to illustrate the principles and implementation manners of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. At the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A 2WIS omnidirectional wheel device, characterized in that: It includes a frame, two independently arranged driving wheels, and at least one driven wheel; The two driving wheels are symmetrically distributed on both sides of the frame in the horizontal direction, and the rotation axes of the driving wheels extend horizontally; Both driving wheels are equipped with a bracket assembly, which includes a steering bracket, a first driving mechanism and a second driving mechanism. One end of the steering bracket is rotatably mounted on the frame, and its rotation axis extends vertically, and is equipped with a first driving mechanism to drive its rotation. The other end of the steering bracket is equipped with a second driving mechanism to drive the driving wheel to rotate. The driven wheel is rotatably mounted on the frame and is supported on the ground together with the two driving wheels.

2. The 2WIS omnidirectional wheel device according to claim 1, characterized in that: A conductive slip ring is provided between the end of each steering bracket where the second driving mechanism is not installed and the frame, and the conductive slip ring includes a stator and a rotor; The stator is mounted on the frame and is used to be electrically connected to the main control mechanism; The rotor is mounted on the steering bracket and is transmission-connected to the first drive mechanism, and its rotation axis extends vertically. The rotor rotates synchronously with the steering bracket, and the wires led out from the rotor are electrically connected to the second drive mechanism.

3. The 2WIS omnidirectional wheel device according to claim 2, characterized in that: Two steering actuators respectively connected to the steering brackets are rotatably mounted on the frame, the rotation axis of the steering actuator extends vertically, and a mounting channel is coaxially penetrated on the steering actuator; The conductive slip ring is embedded in the installation channel, the outer ring of the conductive slip ring is the rotor and is fixedly connected to the steering actuator, and the inner ring of the conductive slip ring is the stator and is fixedly connected to the frame.

4. The 2WIS omnidirectional wheel device according to claim 3, characterized in that: The first driving mechanism is in driving connection with the steering actuator and drives the steering actuator to rotate.

5. The 2WIS omnidirectional wheel device according to claim 3, characterized in that: The first driving mechanism is a driving motor, and the driving motor is provided with a hollow motor shaft serving as the steering actuator.

6. The 2WIS omnidirectional wheel device according to claim 4 or 5, characterized in that: The driving wheel comprises a wheel hub and a tire, the tire is mounted on the rim of the wheel hub, and the second driving mechanism is drivingly connected to the wheel hub.

7. The 2WIS omnidirectional wheel device according to claim 6, characterized in that: The second driving mechanism adopts a wheel hub motor, and the wheel hub motor is built in the inner circumference side of the wheel hub.

8. The 2WIS omnidirectional wheel device according to claim 1, characterized in that: Two driven wheels are mounted on the frame. The two driven wheels are located between the two driving wheels along the arrangement direction of the two driving wheels and are distributed on both sides of the frame along a direction perpendicular to the arrangement direction of the two driving wheels.

9. The 2WIS omnidirectional wheel device according to claim 8, characterized in that: The driven wheel is a universal wheel.

10. A control algorithm applied to the 2WIS omnidirectional wheel device according to any one of claims 1 to 9, characterized in that: Based on the V / W decomposition method, V and W represent the linear velocity and angular velocity of the 2WIS omnidirectional wheel device itself, respectively; Where, linear velocity V = (V x , V y ) T Angular velocity The position formula of the instantaneous center of velocity of the 2WIS omnidirectional wheel device is: ICR =V y / Wz,y ICR =V x / Wz; The linear velocity of each driving wheel is obtained by the geometric relationship between the instantaneous center position and the driving wheel. The linear velocity of the ith driving wheel can be calculated by the following formula: Let the instantaneous center of velocity be I, then the vector from the instantaneous center of velocity to the center of the first driving wheel (the blue part in the figure above) is: in, is the line vector from the center point of the 2WIS omnidirectional wheel device itself to the rotation center of the first driving wheel, is the vector from the center point of the 2WIS omnidirectional wheel device to the instantaneous center of velocity ICR. The vectors are subtracted to obtain the vector from the rotation center of the first driving wheel DE to the instantaneous center of velocity, which is used as the velocity decomposition radius. The position of the first driving wheel is C1(x1, y1); Then the linear velocity at the first driving wheel should be: Among them, X is the outer product of the vector, the cross product; Then the expected linear velocity at the first driving wheel is: The linear velocity of the driving wheel mentioned in the second paragraph is similar and can be expressed as a general formula: Convert the linear velocity of the driving wheel i into the angular velocity of the driving wheel i, where R is the radius of the hub motor: Correspondingly, the steering angle of the driving wheel is: For any After obtaining the control command of each wheel leg using the above formula, each wheel hub motor is placed in speed loop mode and the speed command is: The steering motor of each leg is in position loop mode and the steering angle is: Control for different motion modes The value of .

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