A mobile robot chassis applicable to uneven ground and control method thereof

Abstract

The present invention discloses a mobile robot chassis applicable to uneven ground and a control method thereof, wherein the mobile robot chassis comprises a chassis frame, a Mecanum wheel, a connection unit, a shock-absorbing spring unit, a posture acquisition unit, a power unit and a centralized electronic control unit. When the mobile robot chassis is in a working state, the swing angle sensor of each group of posture acquisition units feeds back the downward swing angle of each group of upper connecting plates relative to the chassis frame to the central controller in real time, and the central controller establishes a real-time kinematic equation of the mobile robot chassis through a data calculation loop, and then the central controller adjusts the control loop so that the drive motor of each group of power units controls their respective Mecanum wheels, and can update and adjust the power distribution of each Mecanum wheel in real time according to the load and road conditions under the premise of ensuring that each Mecanum wheel is in close contact with the ground and the overall operation of the chassis is stable, thereby realizing accurate positioning and movement of the chassis.

Description

Technical Field

[0001] The invention relates to a mobile robot chassis and a control method thereof, in particular to a mobile robot chassis applicable to uneven ground and a control method thereof, belonging to the technical field of mobile robots. Background Art

[0002] Mobile robots are mechanical devices that automatically perform work. They are integrated systems that integrate multiple functions such as environmental perception, dynamic decision-making and planning, and behavior control and execution. Mobile robots can accept human commands, run pre-programmed programs, and act according to principles and guidelines formulated with artificial intelligence technology. As the performance of robots continues to improve, the application scope of mobile robots has greatly expanded. They are not only widely used in industries such as industry, agriculture, medical care, and services, but also in harmful and dangerous situations such as urban security, national defense, and space exploration.

[0003] The chassis of a mobile robot is an important component of a mobile robot, which directly affects the stability, accuracy and reliability of the operation of the mobile robot. Most of the mobile robot chassis in the prior art adopt a differential wheel structure, which has a low cost and good walking stability, but has poor movement flexibility and low carrying capacity. The Mecanum wheel is an omnidirectional movement method that has emerged in recent years. It is a mobile platform that combines four Mecanum wheels that are symmetrical in front and back and left and right. Under the premise of not changing the direction of the Mecanum wheel itself, the different directions and speeds of each Mecanum wheel can be combined to generate a resultant force vector in any direction, thereby ensuring the movement of the mobile platform in the direction of the resultant force vector and realizing omnidirectional movement. Therefore, compared with the mobile robot chassis with a differential wheel structure, the mobile robot chassis with a Mecanum wheel structure has better movement flexibility and greater carrying capacity.

[0004] However, in the prior art, the Mecanum wheels of the mobile robot chassis with a Mecanum wheel structure mostly adopt a non-suspension connection method, that is, the Mecanum wheels are directly positioned and installed on the chassis. On the one hand, this non-suspension connection method has high requirements on the ground flatness of the use environment. The mobile platform composed of four Mecanum wheels is prone to slipping on uneven ground, and it is difficult to meet the requirements of accurate positioning and movement when the chassis moving speed, load and road conditions change greatly. On the other hand, the longitudinal distance or lateral distance between the center of the Mecanum wheel of the non-suspension connection method and the geometric center of the chassis is a constant, so the kinematic equation of the chassis is unchanged, that is, the relationship between the chassis speed set by the program and the Mecanum wheel speed is certain. However, in the actual working environment, different load conditions will cause different degrees of vibration, and the vibration is more obvious under the load condition of eccentric load, which will directly affect the power distribution and efficiency of each Mecanum wheel during the movement process. At the same time, the vibration will also have an adverse effect on the expansion equipment installed on the mobile robot chassis. Summary of the invention

[0005] In view of the above problems, the present invention provides a mobile robot chassis applicable to uneven ground and a control method thereof, which can realize real-time updating and adjustment of the power distribution of each Mecanum wheel according to the load and road conditions, thereby realizing accurate positioning and movement of the chassis, while ensuring that each Mecanum wheel is in close contact with the ground and the overall chassis runs smoothly.

[0006] To achieve the above-mentioned purpose, the mobile robot chassis applicable to uneven ground includes a chassis frame, Mecanum wheels, a connection unit, a shock-absorbing spring unit, a posture acquisition unit, a power unit and a centralized electronic control unit.

[0007] The Mecanum wheels are arranged in four pieces symmetrically relative to the geometric center of the chassis frame, and the four Mecanum wheels are arranged symmetrically in pairs, front and back, and left and right.

[0008] The connecting units are symmetrically arranged in four groups corresponding to the positions of the Mecanum wheels, each group of connecting units includes an upper connecting plate, a bearing seat bracket and a lower connecting plate, the bearing seat bracket with a bearing inside is vertically arranged, the upper connecting plate and the lower connecting plate are inclined downward along the left and right directions, and the upper connecting plate is arranged in parallel with the lower connecting plate, the left and right ends of the upper connecting plate are respectively hingedly installed and connected to the upper end of the bearing seat bracket and the upper frame body plate of the chassis frame, the left and right ends of the lower connecting plate are respectively hingedly installed and connected to the lower end of the bearing seat bracket and the lower frame body plate of the chassis frame, the upper connecting plate, the bearing seat bracket, the lower connecting plate and the chassis frame together form a parallelogram structure, and the four Mecanum wheels are axially positioned and matched and connected on the bearing seat brackets of the four groups of connecting units through the horizontally arranged stepped transmission shaft.

[0009] The shock-absorbing spring units and corresponding connecting units are symmetrically arranged in four groups. Each group of shock-absorbing spring units includes a shock-absorbing spring assembly tilted downward along the left and right directions. The left and right ends of the shock-absorbing spring assembly are respectively hingedly installed and connected to the bearing seat bracket and the chassis frame.

[0010] The posture acquisition units are symmetrically arranged in four groups corresponding to the connection units. Each group of posture acquisition units includes a swing angle sensor, which is fixedly mounted on the upper connection plate or the lower connection plate.

[0011] The power unit corresponding connection units are symmetrically arranged in four groups, each power unit includes a drive motor and a universal joint coupling, the drive motor is fixedly mounted on the chassis frame, and the power output end of the drive motor is installed and connected to the stepped transmission shaft through the universal joint coupling.

[0012] The centralized electric control unit comprises a central controller, a posture detection circuit, a data calculation circuit and an adjustment control circuit. The central controller is electrically connected to the swing angle sensor of each group of posture acquisition units and the drive motor of each group of power units.

[0013] As a further improvement of the present invention, the shock absorbing spring assembly of the shock absorbing spring unit is provided in two pieces, and the two shock absorbing spring assemblies are symmetrically arranged front and back relative to the bearing seat bracket.

[0014] As a further improvement of the present invention, the shock absorbing spring assembly of the shock absorbing spring unit is located at a diagonal position of a parallelogram structure formed by the upper connecting plate, the bearing seat bracket, the lower connecting plate and the chassis frame.

[0015] As a further improvement of the present invention, the left and right ends of the shock-absorbing spring assembly are coaxially mounted and connected to the lower hinged mounting center of the lower connecting plate and the upper hinged mounting center of the upper connecting plate, respectively.

[0016] As a further improvement of the present invention, two bearings are respectively arranged inside the bearing seat bracket along the left and right directions thereof.

[0017] As a further improvement of the present invention, the upper connecting plate and the lower connecting plate are frame structures.

[0018] A control method for a mobile robot chassis applicable to uneven ground, wherein a posture detection circuit controls a swing angle sensor of each group of posture acquisition units to feed back to a central controller in real time the downward swing angle of each group of upper connecting plates or lower connecting plates relative to a chassis frame, and the central controller establishes a real-time kinematic equation of the mobile robot chassis through a data calculation circuit according to the feedback of the swing angle sensor, and then the central controller enables the drive motor of each group of power units to control their respective Mecanum wheels through adjusting the control circuit according to the real-time kinematic equation.

[0019] The central controller establishes the robot coordinate system with the geometric center of the chassis frame as the origin, with the left and right direction as the X-axis, the front and rear direction as the Y-axis, and the up and down direction as the Z-axis. The longitudinal distance from the geometric center of the chassis frame 1 to the axis of the Mecanum wheel 2 is L, and the lateral distances from the geometric center of the chassis frame 1 to the geometric centers of the four Mecanum wheels 2 along the left and right directions are W1, W2, W3, and W4 respectively. Let d1 be the horizontal distance from the geometric center of the chassis frame to the upper hinged installation center of the upper connecting plate, let d2 be the horizontal distance from the upper hinged installation center of the upper connecting plate to the lower hinged installation center of the upper connecting plate, and let d3 be the horizontal distance from the lower hinged installation center of the upper connecting plate to the geometric center of the Mecanum wheel along the left and right directions. Then the lateral distance W from the geometric center of the chassis frame to the geometric centers of the four Mecanum wheels along the left and right directions is i =d1+d2+d3, where d1 and d3 are fixed values, let d1+d3=d, let l be the straight-line distance between the upper hinge installation center of the upper connecting plate and the lower hinge installation center of the upper connecting plate, l is a fixed value, let θ be the downward swing angle of the upper connecting plate relative to the chassis frame obtained by the swing angle sensor of the posture acquisition unit in real time, then d2=lcosθ, the central controller establishes the real-time kinematic equation of the mobile robot chassis as follows:

[0020]

[0021]

[0022]

[0023]

[0024] Among them, ω1, ω2, ω3, and ω4 are the angular velocities of the four Mecanum wheels rotating along the axis of the step transmission shaft, v x is the linear velocity of the chassis frame along the X-axis, v y is the linear velocity of the chassis frame along the Y axis, ω z It is the angular velocity of the chassis frame rotating around the Z axis.

[0025] Compared with the prior art, the parallelogram structure composed of the upper connecting plate, the bearing seat bracket, the lower connecting plate and the chassis frame of the mobile robot chassis applicable to uneven ground can be deformed to adapt to the uneven ground and ensure that each Mecanum wheel is in close contact with the ground; the shock-absorbing spring assembly of the shock-absorbing spring unit can achieve the shock-absorbing effect of the chassis, so that the uneven ground will not cause the vibration of the power unit, thereby ensuring the stability and reliability of the power output of the power unit, and the shock-absorbing spring assembly can also realize the deformation and reset of the parallelogram structure; because the Mecanum wheel is axially positioned by the horizontally arranged stepped transmission shaft and is installed on the bearing seat bracket through the joint connection On the upper side, and bearings are arranged at both ends of the left and right ends of the bearing seat bracket, so that the radial load of the step drive shaft can be evenly distributed and can always remain horizontal, and will not deform with the flatness of the ground and the size of the load, thereby ensuring that the Mecanum wheel can always remain perpendicular to the ground; each group of connection units, shock-absorbing spring units, attitude acquisition units and power units work independently, and the working condition is more stable and efficient. Under the premise of ensuring that each Mecanum wheel is in close contact with the ground and the overall operation of the chassis is stable, the power distribution of each Mecanum wheel can be updated and adjusted in real time according to the load and road conditions, thereby realizing accurate positioning and movement of the chassis. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0027] Figure 2 It is a schematic diagram of the front end structure of the present invention;

[0028] Figure 3 It is a partial enlarged view of the present invention;

[0029] Figure 4 It is a schematic diagram of the three-dimensional structure of the bearing seat bracket of the present invention;

[0030] Figure 5 Schematic diagram of the robot coordinate system of the present invention.

[0031] In the figure: 1. chassis frame, 2. Mecanum wheel, 21. stepped transmission shaft, 3. connecting unit, 31. upper connecting plate, 32. bearing seat bracket, 33. lower connecting plate, 4. shock-absorbing spring unit, 5. posture acquisition unit, 6. power unit, 61. driving motor, 62. universal joint coupling. DETAILED DESCRIPTION

[0032] The present invention will be further described below in conjunction with the accompanying drawings (hereinafter referred to as Figure 2 The left and right directions are described as left and right directions).

[0033] like Figure 1 , Figure 2As shown, the mobile robot chassis applicable to uneven ground includes a chassis frame 1, Mecanum wheels 2, a connection unit 3, a shock-absorbing spring unit 4, a posture acquisition unit 5, a power unit 6 and a centralized electronic control unit.

[0034] The Mecanum wheels 2 are symmetrically arranged in four pieces relative to the geometric center of the chassis frame 1, and the four Mecanum wheels 2 are symmetrically arranged in pairs front and back and left and right.

[0035] The connection units 3 are symmetrically arranged in four groups corresponding to the positions of the Mecanum wheels 2, such as Figure 3 As shown, each group of connecting units 3 includes an upper connecting plate 31, a bearing seat bracket 32 ​​and a lower connecting plate 33. The bearing seat bracket 32 ​​with a bearing inside is vertically arranged, the upper connecting plate 31 and the lower connecting plate 33 are inclined downward in the left and right directions, and the upper connecting plate 31 and the lower connecting plate 33 are arranged in parallel, the left and right ends of the upper connecting plate 31 are respectively hingedly installed and connected to the upper end of the bearing seat bracket 32 ​​and the upper frame plate of the chassis frame 1, and the left and right ends of the lower connecting plate 33 are respectively hingedly installed and connected to the lower end of the bearing seat bracket 32 ​​and the lower frame plate of the chassis frame 1. The upper connecting plate 31, the bearing seat bracket 32, the lower connecting plate 33 and the chassis frame 1 together form a parallelogram structure, and the four Mecanum wheels 2 are respectively axially positioned by the horizontally arranged stepped transmission shaft 21 and are installed on the bearing seat bracket 32 ​​of the four groups of connecting units 3 through connection.

[0036] The shock-absorbing spring units 4 are symmetrically arranged in four groups corresponding to the connecting units 3. Each group of shock-absorbing spring units 4 includes a shock-absorbing spring assembly inclined downward along the left and right directions. The left and right ends of the shock-absorbing spring assembly are respectively hingedly installed and connected to the bearing seat bracket 32 ​​and the chassis frame 1.

[0037] The posture acquisition units 5 are symmetrically arranged in four groups corresponding to the connection units 3 . Each group of posture acquisition units 5 includes a swing angle sensor, which is fixedly mounted on the upper connection plate 31 or the lower connection plate 33 .

[0038] The power unit 6 is symmetrically arranged into four groups corresponding to the connection units 3. Each group of power units 6 includes a drive motor 61 and a universal joint coupling 62. The drive motor 61 is fixedly mounted on the chassis frame 1. The power output end of the drive motor 61 is installed and connected to the stepped transmission shaft 21 through the universal joint coupling 62.

[0039] The centralized electric control unit includes a central controller, a posture detection circuit, a data calculation circuit and an adjustment control circuit. The central controller is electrically connected to the swing angle sensor of each group of posture acquisition units 5 and the drive motor 61 of each group of power units 6 respectively.

[0040] When the mobile robot chassis applicable to uneven ground is in working state, the parallelogram structure composed of the upper connecting plate 31, the bearing seat bracket 32, the lower connecting plate 33 and the chassis frame 1 can be deformed to adapt to the uneven ground and ensure that each Mecanum wheel 2 is in close contact with the ground. The shock-absorbing spring assembly of the shock-absorbing spring unit 4 can realize shock absorption and deformation and reset of the parallelogram structure. The posture detection circuit controls the swing angle sensor of each group of posture acquisition units 5 to feed back the downward swing angle of each group of upper connecting plates 31 or lower connecting plates 33 relative to the chassis frame 1 to the central controller in real time. The central controller establishes the real-time kinematic equation of the mobile robot chassis through the data calculation circuit according to the feedback of the swing angle sensor, and then the central controller makes the drive motor 61 of each group of power units 6 control their respective Mecanum wheels 2 according to the real-time kinematic equation and by adjusting the control circuit.

[0041] like Figure 5 As shown, the central controller establishes the robot coordinate system with the geometric center of the chassis frame 1 as the origin, with the left and right direction as the X-axis, the front and back direction as the Y-axis, and the up and down direction as the Z-axis. The longitudinal distance from the geometric center of the chassis frame 1 to the axis of the Mecanum wheel 2 is L, and the lateral distances from the geometric center of the chassis frame 1 to the geometric centers of the four Mecanum wheels 2 along the left and right directions are W1, W2, W3, and W4, respectively. Since the four Mecanum wheels 2 are symmetrically arranged in pairs, the longitudinal distance L is a fixed value, and the lateral distances W1, W2, W3, and W4 will change with the vibration of each Mecanum wheel 2 and different load conditions.

[0042] like Figure 2 As shown, let d1 be the horizontal distance from the geometric center of the chassis frame 1 to the upper hinged installation center of the upper connecting plate 31 (or the lower connecting plate 33), let d2 be the horizontal distance from the upper hinged installation center of the upper connecting plate 31 (or the lower connecting plate 33) to the lower hinged installation center of the upper connecting plate 31 (or the lower connecting plate 33), let d3 be the horizontal distance from the lower hinged installation center of the upper connecting plate 31 (or the lower connecting plate 33) to the geometric center of the Mecanum wheel 2 in the left-right direction, then the lateral distance W from the geometric center of the chassis frame 1 to the geometric centers of the four Mecanum wheels 2 in the left-right direction i =d1+d2+d3, where d1 and d3 are fixed values, let d1+d3=d, let l be the straight-line distance between the upper hinged installation center of the upper connecting plate 31 (or the lower connecting plate 33) and the lower hinged installation center of the upper connecting plate 31 (or the lower connecting plate 33), l is a fixed value, let θ be the downward swing angle of the upper connecting plate 31 (or the lower connecting plate 33) relative to the chassis frame 1 obtained by the swing angle sensor of the posture acquisition unit 5 in real time, then d2=lcosθ, the central controller establishes the kinematic equation of the mobile robot chassis as follows:

[0043]

[0044]

[0045]

[0046]

[0047] Wherein, ω1, ω2, ω3, and ω4 are the angular velocities of the four Mecanum wheels 2 rotating along the axis of the stepped transmission shaft 21, and v x is the linear velocity of chassis frame 1 along the X-axis, v y is the linear velocity of chassis frame 1 along the Y axis, ω z It is the angular velocity of the chassis frame 1 rotating around the Z axis.

[0048] In order to achieve balanced force on the connecting unit 3 , as a further improvement of the present invention, the shock absorbing spring assembly of the shock absorbing spring unit 4 is provided in two pieces, and the two shock absorbing spring assemblies are symmetrically arranged front and back relative to the bearing seat bracket 32 ​​.

[0049] In order to achieve a better deformation and reset effect of the parallelogram structure of the connecting unit 3, as a further improvement scheme of the present invention, the shock-absorbing spring assembly of the shock-absorbing spring unit 4 is located at the diagonal position of the parallelogram structure composed of the upper connecting plate 31, the bearing seat bracket 32, the lower connecting plate 33 and the chassis frame 1.

[0050] In order to achieve a better deformation resetting effect of the parallelogram structure of the connecting unit 3, as a further improvement scheme of the present invention, the left and right ends of the shock-absorbing spring assembly are coaxially installed and connected with the lower hinged installation center of the lower connecting plate 33 and the upper hinged installation center of the upper connecting plate 31 respectively.

[0051] In order to achieve a better supporting transmission effect of the stepped transmission shaft 21, as a further improvement scheme of the present invention, Figure 4 As shown, two bearings are respectively arranged inside the bearing seat bracket 32 ​​along the left and right directions thereof.

[0052] In order to reduce the overall weight while ensuring the supporting strength, as a further improvement of the present invention, the upper connecting plate 31 and the lower connecting plate 33 are frame structures.

[0053] The mobile robot chassis applicable to uneven ground can update and adjust the power distribution of each Mecanum wheel 2 in real time according to the load and road conditions, thereby realizing accurate positioning and movement of the chassis, while ensuring that each Mecanum wheel 2 is in close contact with the ground and the overall chassis runs smoothly.

Claims

1. A mobile robot chassis applicable to uneven ground, comprising a chassis frame (1), Mecanum wheels (2), a power unit (6) and a centralized electronic control unit; the Mecanum wheels (2) are arranged in four pieces symmetrically relative to the geometric center of the chassis frame (1), and the four Mecanum wheels (2) are arranged symmetrically in pairs in front and back and left and right directions; characterized in that: The mobile robot chassis applicable to uneven ground also includes a connection unit (3), a shock-absorbing spring unit (4) and a posture acquisition unit (5); The connection units (3) are symmetrically arranged in four groups corresponding to the positions of the Mecanum wheels (2). Each group of connection units (3) includes an upper connection plate (31), a bearing seat bracket (32) and a lower connection plate (33). The bearing seat bracket (32) with a bearing inside is vertically arranged. The upper connection plate (31) and the lower connection plate (33) are inclined downward in the left-right direction, and the upper connection plate (31) and the lower connection plate (33) are arranged in parallel. The upper connection plate (31) and the lower connection plate (33) are frame structures. The left and right ends of the upper connection plate (31) are respectively connected to the shaft. The upper end of the bearing support (32) is hingedly installed and connected to the upper frame plate of the chassis frame (1); the left and right ends of the lower connecting plate (33) are respectively hingedly installed and connected to the lower end of the bearing support support (32) and the lower frame plate of the chassis frame (1); the upper connecting plate (31), the bearing support support (32), the lower connecting plate (33) and the chassis frame (1) together form a parallelogram structure; the four Mecanum wheels (2) are respectively axially positioned and matched and connected to the bearing support supports (32) of the four groups of connection units (3) through the horizontally arranged stepped transmission shaft (21); The shock absorbing spring units (4) are symmetrically arranged in four groups corresponding to the connecting units (3), each group of shock absorbing spring units (4) comprises a shock absorbing spring assembly arranged to be tilted downward in the left-right direction, the left and right ends of the shock absorbing spring assembly are respectively hingedly installed and connected to the bearing seat bracket (32) and the chassis frame (1), and the shock absorbing spring assembly is located at the diagonal position of the parallelogram structure formed by the upper connecting plate (31), the bearing seat bracket (32), the lower connecting plate (33) and the chassis frame (1); The posture acquisition units (5) are symmetrically arranged in four groups corresponding to the connection units (3), and each group of posture acquisition units (5) includes a swing angle sensor, which is fixedly mounted on the upper connection plate (31) or the lower connection plate (33); The power units (6) are symmetrically arranged in four groups corresponding to the connecting units (3), each group of power units (6) comprises a driving motor (61) and a universal joint coupling (62), the driving motor (61) is fixedly mounted on the chassis frame 1, and the power output end of the driving motor (61) is mounted and connected to the stepped transmission shaft (21) via the universal joint coupling (62); The centralized electric control unit comprises a central controller, a posture detection circuit, a data calculation circuit and an adjustment control circuit. The central controller is electrically connected to the swing angle sensor of each group of posture acquisition units (5) and the drive motor (61) of each group of power units (6).

2. The mobile robot chassis applicable to uneven ground according to claim 1, characterized in that: The shock absorbing spring assembly of the shock absorbing spring unit (4) is provided in two pieces, and the two shock absorbing spring assemblies are symmetrically arranged front and back relative to the bearing seat bracket (32).

3. The mobile robot chassis applicable to uneven ground according to claim 1, characterized in that: The left and right ends of the shock-absorbing spring assembly are coaxially mounted and connected to the lower hinged mounting center of the lower connecting plate (33) and the upper hinged mounting center of the upper connecting plate (31), respectively.

4. The mobile robot chassis applicable to uneven ground according to claim 1 or 2, characterized in that: Two bearings are respectively arranged inside the bearing seat bracket (32) along the left and right directions thereof.

5. A control method for a mobile robot chassis applicable to uneven ground as claimed in claim 1, characterized in that: The posture detection circuit controls the swing angle sensor of each group of posture acquisition units (5) to feed back the downward swing angle of each group of upper connecting plates (31) or lower connecting plates (33) relative to the chassis frame (1) to the central controller in real time. The central controller establishes the real-time kinematic equation of the mobile robot chassis through the data calculation circuit according to the feedback of the swing angle sensor. Then, the central controller controls the driving motor (61) of each group of power units (6) to control the respective Mecanum wheels (2) according to the real-time kinematic equation by adjusting the control circuit.

6. The control method of a mobile robot chassis applicable to uneven ground according to claim 5, characterized in that: The central controller establishes a robot coordinate system with the geometric center of the chassis frame (1) as the origin, with the left-right direction as the X-axis, the front-back direction as the Y-axis, and the up-down direction as the Z-axis. The longitudinal distance from the geometric center of the chassis frame (1) to the axis of the Mecanum wheel (2) is L, and the lateral distances from the geometric center of the chassis frame (1) to the geometric centers of the four Mecanum wheels (2) in the left-right direction are W1, W2, W3, and W4, respectively. Let d1 be the horizontal distance from the geometric center of the chassis frame (1) to the upper hinged installation center of the upper connecting plate (31), let d2 be the horizontal distance from the upper hinged installation center of the upper connecting plate (31) to the lower hinged installation center of the upper connecting plate (31), and let d3 be the horizontal distance from the lower hinged installation center of the upper connecting plate (31) to the geometric center of the Mecanum wheel (2) in the left-right direction. Then, the lateral distance W from the geometric center of the chassis frame (1) to the geometric centers of the four Mecanum wheels (2) in the left-right direction is i =d1+d2+d3, where d1 and d3 are fixed values, let d1+d3=d, let l be the straight-line distance between the upper hinged installation center of the upper connecting plate (31) and the lower hinged installation center of the upper connecting plate (31), l is a fixed value, let θ be the downward swing angle of the upper connecting plate (31) relative to the chassis frame (1) obtained by the swing angle sensor of the posture acquisition unit (5) in real time, then d2=lcosθ, the central controller establishes the real-time kinematic equation of the mobile robot chassis as follows: Wherein, ω1, ω2, ω3, ω4 are the angular velocities of the four Mecanum wheels (2) rotating along the axis of the step transmission shaft (21), v x is the linear velocity of the chassis frame (1) along the X-axis, v y is the linear velocity of the chassis frame (1) along the Y axis, ω z It is the angular velocity of the chassis frame (1) rotating with the Z axis as the rotation axis.

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