Two-wheel differential mobile robot chassis

Abstract

The application discloses a two-wheel differential mobile robot chassis. The mobile robot chassis comprises a bottom plate, a driving wheel, a driven wheel, a driving wheel shock absorption unit, a driven wheel shock absorption unit and a power module. The mobile robot chassis is centrally symmetrically arranged as a whole, one driving wheel is arranged on each side, and two driven wheels are arranged at the front and rear. The driving wheel is damped by the driving wheel shock absorption unit, and the driven wheel is damped by the driven wheel shock absorption unit. Each wheel of the chassis is equipped with an independent shock absorption unit, can smoothly pass through uneven road surfaces, and has good load capacity.

Description

Technical Field

[0001] This invention relates to a wheeled chassis in the field of mobile robots, and more particularly to a two-wheeled differential mobile robot chassis with a shock absorption structure. Background Technology

[0002] With the continuous advancement of artificial intelligence technology, mobile robots, as a new type of intelligent device, have gradually attracted attention. In practical applications, mobile robots can be used in various scenarios, such as logistics delivery, medical services, and security monitoring. The performance of mobile robots in specific scenarios largely depends on their chassis structure. Currently, the most common mobile robot chassis on the market are mainly divided into wheeled chassis, legged chassis, and wheel-legged chassis. The latter two are biomimetic structures, possessing excellent capabilities for outdoor movement and stair climbing, and can adapt to various terrains. However, their structures are complex, their costs are high, and their control effects are greatly affected by software algorithms. Wheeled chassis are more popular, and in terms of steering structure, they are mainly divided into Ackerman chassis, omnidirectional mobile chassis, and differential mobile chassis. Ackerman chassis are mainly used in outdoor scenarios, but they have a large turning radius and cannot rotate on their own, and their structure is relatively complex. Omnidirectional mobile chassis have high flexibility and can move in any direction on a plane, but their drive wheels use Mecanum wheels or omnidirectional wheels, resulting in weak load capacity and poor adaptability to terrain. Differential mobile chassis are divided into two-wheel, four-wheel, and tracked chassis. The rotation of a four-wheel differential chassis relies on the sliding friction between the wheels and the ground, which causes significant wear on the wheels. Tracked chassis have a more complex track structure, resulting in higher maintenance costs and the risk of damaging the ground when moving on indoor surfaces. Two-wheel differential mobile chassis have a simpler construction and higher control precision, but they are prone to slipping on uneven surfaces, which affects their reliability. Summary of the Invention

[0003] To address the problems and needs in the background technology, this invention provides a two-wheeled differential mobile robot chassis. More specifically, it is a mobile robot that adopts a two-wheeled differential kinematic model, with both the driving and driven wheels equipped with independent shock absorption, and is capable of remote control and autonomous operation while sensing the surrounding environment.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0005] The present invention includes a base plate, a second layer plate, a profile, a drive wheel, a driven wheel, a drive wheel shock absorber unit, a driven wheel shock absorber unit, and a power module. Multiple drive wheels are arranged on the side of the base plate. The second layer plate is fixedly mounted on the base plate via the profile. Multiple drive wheel shock absorber units are installed in both the base plate and the second layer plate, each drive wheel shock absorber unit being connected to its corresponding drive wheel. Multiple driven wheels are installed under the base plate. Multiple driven wheel shock absorber units are installed on the side of the second layer plate, each driven wheel shock absorber unit passing through the base plate and connected to its corresponding driven wheel. The power module is mounted on the base plate and connected to the multiple drive wheels.

[0006] The active wheel shock absorber unit includes a bearing housing, flange, hinge, universal joint coupling, first mounting plate, universal support components for upper and lower chassis, shock absorber mounting base, shock absorber vertical mounting base, first thickened central shaft metal shock absorber, and negative pressure shock absorber.

[0007] The upper and lower end faces of the bearing housing are hinged to one end of the corresponding first mounting plate via hinges. The other ends of the upper and lower first mounting plates are hinged to the sides of the second layer plate and the bottom plate via hinges, so that the bearing housing is installed on the sides of the second layer plate and the bottom plate. The second layer plate and the bottom plate near the bearing housing are fixedly connected by a universal support component of the upper and lower chassis. A negative pressure shock absorber is provided on each side of the bearing housing. The bottom end of each negative pressure shock absorber is connected to the bottom of the bearing housing, and the top end of each negative pressure shock absorber is connected to the corresponding universal support component of the upper and lower chassis. A bearing is installed in the bearing housing. The drive wheel is coaxially connected to the bearing in the bearing housing via a flange. A power module is installed on the bottom plate inside the bearing housing. The power module is coaxially connected to the bearing in the bearing housing via a universal joint coupling. The bottom end of the first thickened central shaft metal shock absorber is hinged to the first mounting plate above the universal joint coupling via a shock absorber mounting seat. The top end of the first thickened central shaft metal shock absorber is hinged to the second layer plate via a shock absorber vertical mounting seat.

[0008] The driven wheel shock absorber unit includes a driven wheel mounting plate, a connecting rod, and a second thickened central shaft metal shock absorber; the top of the second thickened central shaft metal shock absorber is connected to the second layer plate, and the bottom of the second thickened central shaft metal shock absorber is connected to the driven wheel mounting plate. The two sides of the driven wheel mounting plate are respectively hinged to the lower surface of the second layer plate through corresponding connecting rods, and a corresponding driven wheel is installed under the driven wheel mounting plate.

[0009] The driven wheel is a swivel wheel, which can face any direction.

[0010] The power module includes a first power lithium battery, a brushless motor, a motor mount, and a battery bracket; the first power lithium battery is connected to the brushless motor and is mounted on the upper surface of the base plate via the battery bracket; the brushless motor is fixed on two motor mounts; and the output shaft of the brushless motor is connected to the active wheel shock absorption unit.

[0011] The second layer board also includes a lower-level computer, a higher-level computer, a level conversion module, a one-button start button, and an inertial sensor.

[0012] The third layer is mounted on the second layer via profiles, and the lidar is mounted in front of the third layer.

[0013] Compared with the prior art, the beneficial effects of the present invention are:

[0014] 1. This invention provides a novel two-wheeled differential mobile robot chassis structure, which has two active wheels and four driven wheels. The driven wheels are omnidirectional wheels. The chassis kinematic model is simple and the control precision is high.

[0015] 2. The active wheel shock absorption unit and the driven wheel shock absorption unit of the present invention can maximize the contact between each wheel of the active wheel and the driven wheel and the ground during movement, prevent slippage, and have high stability when passing through rough and uneven road surfaces, and have good obstacle crossing ability.

[0016] 3. The power module of this invention comprises two independent lithium batteries, which respectively power the brushless motor and other low-voltage electronic components, forming electrical isolation in hardware and ensuring stable operation. The two lithium batteries are respectively fixed to the base plate by battery racks and straps, facilitating disassembly and installation during charging.

[0017] 4. The mobile robot chassis of the present invention has two working modes: remote control mode and autonomous mode. In remote control mode, the host computer does not participate in the work, and the slave computer is responsible for communicating with the remote controller and controlling the movement of the chassis. In autonomous mode, the host computer is responsible for scheduling and running the upper-level perception and decision-making algorithms, and the slave computer is responsible for motion control.

[0018] 5. The overall frame of this invention is constructed from aluminum plates and profiles, resulting in a simple structure, low cost, and ample internal space for adding additional sensor components. All structures employ a modular design, facilitating future maintenance and replacement. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall chassis structure of the present invention. Figure 1 ;

[0020] Figure 2 This is a schematic diagram of the overall chassis structure of the present invention. Figure 2 ;

[0021] Figure 3 This is a front view of the chassis of the present invention;

[0022] Figure 4 This is a rear view of the chassis of the present invention;

[0023] Figure 5 This is a left view of the chassis of the present invention;

[0024] Figure 6 This is a schematic diagram of the active wheel shock absorption unit structure in this invention;

[0025] Figure 7 This is a schematic diagram of the driven wheel shock absorber unit structure in this invention;

[0026] Figure 8 This is a schematic diagram of the power module structure in this invention;

[0027] Figure 9 This is a schematic diagram of the structure in this invention, omitting the third layer plate;

[0028] In the diagram: 1. Third layer plate, 2. Second layer plate, 3. Base plate, 4. Profile, 5. Drive wheel, 6. Driven wheel, 10. Lower computer, 11. Upper computer, 12. Inertial sensor, 13. LiDAR, 14. One-button start, 15. Level conversion module, 51. First drive wheel, 52. Second drive wheel, 70. Drive wheel shock absorber unit, 701. First thickened central shaft metal shock absorber, 702. Shock absorber mounting base, 703. Hinge, 704. Flange, 705. Bearing housing, 706. First mounting plate, 707. Universal joint 708. Joint coupling; 709. Negative pressure shock absorber; 710. Universal support for upper and lower chassis; 80. Vertical mounting base for shock absorber; 810. Driven wheel shock absorber unit; 801. Chassis mounting plate; 802. Connecting rod; 803. Angle bracket; 804. Driven wheel mounting plate; 805. Connecting rod mounting base; 806. Second thickened central shaft metal shock absorber; 90. Power module; 901. Second power lithium battery; 902. Brushless motor; 903. Motor mount; 904. Brushless motor speed controller; 905. Battery bracket; 906. First power lithium battery. Detailed Implementation

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] like Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, the mobile robot chassis includes a base plate 3, a second layer plate 2, a profile 4, a drive wheel 5, a driven wheel 6, a drive wheel shock absorption unit 70, a driven wheel shock absorption unit 80, and a power module 90;

[0031] Multiple drive wheels 5 are provided on the side of the base plate 3. The second layer plate 2 is sequentially fixed to the base plate 3 via profiles 4. Multiple drive wheel shock absorption units 70 are installed in the base plate 3 and the second layer plate 2. Each drive wheel shock absorption unit 70 is connected to the corresponding drive wheel 5. Multiple driven wheels 6 are installed under the base plate 3 and are arranged between the drive wheels 5. In specific implementation, there are two driven wheels 5 at the front and two at the back of the base plate 3. Multiple driven wheel shock absorption units 80 are installed on the sides (i.e., the front and rear sides) of the second layer plate 2. Each driven wheel shock absorption unit 80 passes through the base plate 3 and is connected to the corresponding driven wheel 6. The power module 90 is installed on the base plate 3 and is connected to the multiple drive wheels 5. The kinematic model of the two-wheel differential mobile robot chassis adopts a two-wheel differential model. The chassis's overall frame consists of a base plate 3, a second layer plate 2, a third layer plate 1, and profiles 4. The base plate 3 and the second layer plate 2 are connected by 12 profiles, each 66mm high, and the second layer plate 2 and the third layer plate 1 are also connected by 12 profiles, each 66mm high. The profiles are symmetrically distributed front-to-back about the chassis's geometric center. Both ends of the profiles 4 are threaded and secured directly with bolts.

[0032] like Figure 6 As shown, the active wheel shock absorber unit 70 includes a bearing housing 705, a flange 704, a hinge 703, a universal joint coupling 707, a first mounting plate 706, a universal support component for the upper and lower chassis 709, a shock absorber mounting base 702, a shock absorber vertical mounting base 710, a first thickened central shaft metal shock absorber 701, and a negative pressure shock absorber 708.

[0033] The upper and lower end faces of the bearing housing 705 are respectively hinged to one end of the corresponding first mounting plate 706 via hinges 703. The other ends of the two first mounting plates 706 are respectively hinged to the sides of the second layer plate 2 and the bottom plate 3 via hinges 703. The hinges 703 are fixed to the first mounting plate 706, the second layer plate 2 and the bottom plate 3 by bolts, so that the bearing housing 705 is installed on the side of the second layer plate 2 and the bottom plate 3. The second layer plate 2 and the bottom plate 3 near the bearing housing 705 are fixedly connected by two universal upper and lower chassis support members 709. The two universal upper and lower chassis support members 709 are installed between the bottom plate 3 and the second layer plate 2 at a certain distance. A negative pressure shock absorber 708 is provided on each side of the bearing housing 705. The bottom end of each negative pressure shock absorber 708 is connected to the bottom of the bearing housing 705, and the top end of each negative pressure shock absorber 708 is connected to the corresponding universal upper and lower chassis support member 709.

[0034] A bearing is installed in the bearing housing 705. The drive wheel 5 is coaxially connected to the bearing in the bearing housing 705 via a flange 704. The flange 704 is fixed to the drive wheel 5 with bolts and nuts. A power module 90 is installed on the base plate 3 inside the bearing housing 705. The output shaft of the brushless motor 902 of the power module 90 is coaxially connected to the bearing in the bearing housing 705 via a universal joint coupling 707. That is, the output shaft of the brushless motor 902 in the power module 90 is connected to the drive wheel 5. The axes of the central shafts do not coincide, and they are connected by a universal joint coupling 707. Each end of the coupling has a universal joint, ensuring that the brushless motor 902, whose axes do not coincide, rotates at the same speed as the drive wheel 5. The bottom end of the first thickened central shaft metal shock absorber 701 is hinged to the first mounting plate 706 above the universal joint coupling 707 via a shock absorber mounting base 702, and the top end of the first thickened central shaft metal shock absorber 701 is hinged to the second layer plate 2 via a shock absorber vertical mounting base 710. The overall structure of the drive wheel shock absorber unit 70 is a parallelogram-shaped shock absorber structure. During the movement of the two-wheeled differential mobile robot chassis on rough and uneven surfaces, the hinge in the hinge 703 can rotate, and the two ends of the shock absorber can rotate around the fixing bolts. This allows the bearing seat 705 and flange 704 on the outside of the drive wheel shock absorber unit 70 to drive the drive wheel 5 to move perpendicular to the ground.

[0035] In specific implementation, the shock absorber mounting base 702 is a 3mm shock absorber mounting base, and the shock absorber vertical mounting base 710 is also a 3mm shock absorber vertical mounting base. In specific implementation, there are two drive wheels, designated as the first drive wheel 51 and the second drive wheel 52. The first drive wheel 51 is located on the left side of the chassis, and the second drive wheel 52 is located on the right side of the chassis. They are symmetrically distributed about the geometric center of the chassis, and the line connecting the centers of the drive wheels coincides with the geometric center of the chassis. The drive wheels 51 and the drive wheel shock absorber unit 70 are connected by a flange 704. The drive wheels 51 are made of rubber tires, providing good shock absorption and grip. A coordinate system is established with the chassis geometric center as the origin. The X direction is the front of the chassis, the Y direction is the left side of the chassis, and the Z direction is perpendicular to the chassis and upwards. Since the drive wheels can only roll radially and cannot slide axially, although the chassis has two translational degrees of freedom and one rotational degree of freedom, only the linear velocity v in the X direction can actually be controlled. x And the angular velocity of rotation ω.

[0036] like Figure 7 As shown, the driven wheel shock absorber unit 80 includes a driven wheel mounting plate 804, a chassis mounting plate 801, a corner bracket 803, a connecting rod mounting seat 805, a connecting rod 802, and a second thickened central shaft metal shock absorber 806;

[0037] The top of the second thickened central shaft metal shock absorber 806 is connected to the second layer plate 2. In specific implementation, the chassis mounting plate 801 is fixed above the second layer plate 2 by copper pillars. Two corner brackets 803 are installed below the chassis mounting plate 801, and the chassis mounting plate 801 is connected to the top of the second thickened central shaft metal shock absorber 806 through the two corner brackets 803. The bottom of the second thickened central shaft metal shock absorber 806 is connected to the driven wheel mounting plate 804 through the corner brackets 803. The two corner brackets 803 are connected to the driven wheel mounting plate through bolts and nuts. The driven wheel mounting plate 804 is fixedly connected to the lower surface of the second layer plate 2 via corresponding connecting rod mounting seats 805 and connecting rods 802 on both sides. Two connecting rod mounting seats 805 are installed under the second layer plate 2. Connecting rod mounting seats 805 are fixedly installed on both sides of the driven wheel mounting plate 804. Each connecting rod mounting seat 805 has two through holes on its upright. The two ends of the connecting rod 802 are hinged to the connecting rod mounting seats 805 on the driven wheel mounting plate 804 and the connecting rod mounting seats 805 below the second layer plate 2, respectively. A corresponding driven wheel 6 is installed under the driven wheel mounting plate 804 via bolts and nuts. The driven wheel 6 is a swivel wheel, allowing it to face in any direction. The driven wheel shock absorber unit 80 has a parallelogram-shaped shock absorber structure. The through hole at the end of the connecting rod 802 corresponds to the through hole on the connecting rod mounting base 805. They are connected by bolts and nuts. The connecting rod 802 can rotate around the bolt, and the two ends of the shock absorber can rotate around the fixing bolt, thereby driving the driven wheel mounting plate 804 and the driven wheel 6 to move in a direction perpendicular to the ground. The upper surface of the driven wheel mounting plate 804 always remains parallel to the shelf of the mobile robot chassis.

[0038] like Figure 8 As shown, the power module 90 includes a first power lithium battery 906, a second power lithium battery 901, a voltage regulator module 907, a brushless motor 902, a brushless motor speed controller 904, a motor mount 903, and a battery bracket 905.

[0039] The first power lithium battery 906 is connected to the brushless motor 902, providing power to the brushless motor 902. The second power lithium battery 901 provides power to other electronic components in the chassis. The first power lithium battery 906 is mounted on the rear of the upper surface of the base plate 3 via a battery bracket 905. Both lithium batteries have a rated voltage of 24V. To install the first power lithium battery 906, simply push it into the battery bracket 905 with the bottom surface facing down. The protrusions on both sides of the battery engage with the clips on the battery bracket 905 to secure it. To remove the battery, simply pull it out by holding the protrusions on both sides. The second power lithium battery 901 is secured to the front of the base plate 3 using straps. Two motor mounts 903, symmetrically positioned about the geometric center of the chassis, are installed on both sides of the base plate 3. A brushless motor 902 is bolted to each of the two motor mounts 903. The output shaft of the brushless motor 902 is fixedly connected to one end of the corresponding universal joint coupling 707 in the drive wheel shock absorber unit 70. A brushless motor speed controller 904 is bolted to the rear of the base plate 1. A first power lithium battery 906 is directly connected to the brushless motor speed controller 903 to power the brushless motor 902, whose rated voltage is 24V. A voltage regulator module 907 is fixed to the front right of the base plate 3 and is directly connected to the second power lithium battery 901 to stabilize the DC voltage to 12V for output to other electronic components. During the operation of the brushless motor 902, there may be sudden current fluctuations. Since the discharge power of lithium batteries is limited, two lithium batteries are used to power the motor and other electronic components respectively, forming electrical isolation in the hardware and stabilizing the power supply to other electronic components.

[0040] like Figure 9 As shown, the second layer plate 2 also houses a lower-level computer 10, a higher-level computer 11, a level conversion module 15, a one-button start button 14, and an inertial sensor 12. The lower-level computer 10 is installed in the center of the second layer plate 2, and the higher-level computer 11 is installed at the front of the second layer plate 2, with the side of the higher-level computer 11 with its interface facing the front of the chassis for easy connection of expansion devices. The level conversion module 15 is installed behind the lower-level computer 10. The one-button start button 14 is embedded in the front left side of the second layer plate 2. The inertial sensor 12 is installed on the second layer plate, located between the lower-level computer 10 and the higher-level computer 11, coinciding with the front and rear geometric center lines of the chassis. The third layer plate 1 is mounted on the second layer plate 2 via a profile, and the lidar 13 is installed at the front of the third layer plate 1 to prevent its field of view from being limited. The lidar 13 is connected to the higher-level computer 11.

[0041] When the one-button start 14 is pressed, the chassis system powers on; when pressed again, the system powers off. Except for the brushless motor 902, all electronic components in the chassis are powered by a 12V DC voltage output from the voltage regulator module 907. The output of the voltage regulator module 907 is first connected to the lower-level computer 10. The integrated circuit in the lower-level computer 10 further reduces the voltage to 3.3V and 5V, and an additional power supply interface is led out on the side. The lower-level computer 10, the level conversion module 15, and the inertial sensor 12 are connected to a 3.3V DC voltage, while the upper-level computer 11 is connected to a 5V DC voltage. The lower-level computer 10 is mainly responsible for real-time reading of the brushless motor 902's rotational speed information, the angular velocity information returned by the inertial sensor 12, and the remote control data, and obtaining the chassis's linear velocity v in the X-direction of its own coordinate system through a forward kinematics model. x The system sends the rotational angular velocity ω to the host computer 11 and simultaneously receives the real-time required linear velocity and angular velocity calculated by the host computer 11. Using an inverse kinematics model, it calculates the required speeds of the left and right brushless motors 902, and finally achieves speed closed-loop control via a PID controller. The slave computer 10 controls the speed of the brushless motor 902 by sending data containing current values ​​to the brushless motor speed controller 904. Since the slave computer 10 uses TTL level communication while the brushless motor speed controller 904 uses CAN level communication, a level conversion module 15 is needed to establish a communication link between them. It should be noted that communication between the slave computer 10 and the host computer 11 only occurs in autonomous mode. In remote control mode, the slave computer 10 only needs to receive data from the remote control to control the chassis movement. In autonomous mode, the mapping algorithm in the host computer 11 is responsible for building a two-dimensional grid map of the environment. The navigation algorithm plans the movement path in real time based on the established map and the target point, and sends the required linear velocity and angular velocity to the lower computer 10. The mobile robot chassis can autonomously go there by simply setting the target point in the host computer.

[0042] The mobile robot chassis operates in two modes: remote control and autonomous mode. In remote control mode, the host computer does not participate in the operation. The chassis slave computer parses the data received from the remote controller and obtains the real-time speed required for each motor through inverse kinematics calculation. The PID control algorithm then enables the drive wheel to reach the desired speed. In autonomous mode, the mapping algorithm in the host computer is responsible for building a two-dimensional grid map of the environment. The navigation algorithm plans the movement path in real time based on the established map and the target points, and sends the required speed commands to the slave computer. The slave computer controls the motors to reach the desired speed and simultaneously uploads the collected motor speed information and the angular velocity information read from the inertial sensor to the host computer to synthesize odometer information.

[0043] The specific usage described above represents only a portion of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

Claims

1. A chassis for a two-wheeled differential mobile robot, characterized in that, It includes a base plate (3), a second layer plate (2), a profile (4), a drive wheel (5), a driven wheel (6), a drive wheel shock absorber unit (70), a driven wheel shock absorber unit (80), and a power module (90); the side of the base plate (3) is provided with multiple drive wheels (5), the second layer plate (2) is fixedly installed on the base plate (3) through the profile (4), multiple drive wheel shock absorber units (70) are installed in the base plate (3) and the second layer plate (2), each drive wheel shock absorber unit (70) is connected to the corresponding drive wheel (5), multiple driven wheels (6) are installed under the base plate (3), multiple driven wheel shock absorber units (80) are installed on the side of the second layer plate (2), each driven wheel shock absorber unit (80) passes through the base plate (3) and is connected to the corresponding driven wheel (6), the power module (90) is installed on the base plate (3) and the power module (90) is connected to multiple drive wheels (5); The active wheel shock absorber unit (70) includes a bearing housing (705), a flange (704), a hinge (703), a universal joint coupling (707), a first mounting plate (706), a universal support component for the upper and lower chassis (709), a shock absorber mounting base (702), a vertical shock absorber mounting base (710), a first thickened central shaft metal shock absorber (701), and a negative pressure shock absorber (708). The upper and lower end faces of the bearing housing (705) are respectively hinged to one end of the corresponding first mounting plate (706) via hinges (703). The other ends of the two first mounting plates (706) are respectively hinged to the sides of the second layer plate (2) and the bottom plate (3) via hinges (703), so that the bearing housing (705) is installed on the sides of the second layer plate (2) and the bottom plate (3). The second layer plate (2) and the bottom plate (3) near the bearing housing (705) are fixedly connected by the universal support member (709) of the upper and lower chassis. A negative pressure shock absorber (708) is provided on each side of the bearing housing (705). The bottom end of each negative pressure shock absorber (708) is connected to the bottom of the bearing housing (705), and the top end of each negative pressure shock absorber (708) is connected to the corresponding upper and lower chassis universal support (709). A bearing is installed in the bearing housing (705). The drive wheel (5) is coaxially connected to the bearing in the bearing housing (705) through a flange (704). The bottom plate (3) on the inner side of the bearing housing (705) A power module (90) is installed on the ) and the power module (90) is coaxially connected to the bearing in the bearing housing (705) through a universal joint coupling (707); the bottom end of the first thickened central shaft metal shock absorber (701) is hinged to the first mounting plate (706) above the universal joint coupling (707) through the shock absorber mounting base (702), and the top end of the first thickened central shaft metal shock absorber (701) is hinged to the second layer plate (2) through the shock absorber vertical mounting base (710); The driven wheel shock absorber unit (80) includes a driven wheel mounting plate (804), a connecting rod (802), and a second thickened central shaft metal shock absorber (806). The top end of the second thickened central shaft metal shock absorber (806) is connected to the second layer plate (2), and the bottom end of the second thickened central shaft metal shock absorber (806) is connected to the driven wheel mounting plate (804). The two sides of the driven wheel mounting plate (804) are respectively hinged to the lower surface of the second layer plate (2) through the corresponding connecting rods (802). A corresponding driven wheel (6) is installed under the driven wheel mounting plate (804).

2. The chassis of a two-wheeled differential mobile robot according to claim 1, characterized in that, The driven wheel (6) is a swivel wheel, which can face any direction.

3. The chassis of a two-wheeled differential mobile robot according to claim 1, characterized in that, The power module (90) includes a first power lithium battery (906), a brushless motor (902), a motor mount (903), and a battery bracket (905); the first power lithium battery (906) is connected to the brushless motor (902), the first power lithium battery (906) is mounted on the upper surface of the base plate (3) through the battery bracket (905), the brushless motor (902) is fixed on two motor mounts (903), and the output shaft of the brushless motor (902) is connected to the active wheel shock absorber unit (70).

4. The chassis of a two-wheeled differential mobile robot according to claim 1, characterized in that, The second layer board (2) is also equipped with a lower computer (10), a higher computer (11), a level conversion module (15), a one-key start button (14) and an inertial sensor (12).

5. The chassis of a two-wheeled differential mobile robot according to claim 1, characterized in that, The third layer plate (1) is installed on the second layer plate (2) by a profile, and the lidar (13) is installed in front of the third layer plate (1).

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