A statically unstable wheeled mobile robot and its control method

Abstract

This invention relates to the technical field of two-wheeled self-balancing vehicles, and more specifically, to a statically unstable wheeled mobile robot and its control method. The robot includes a first balancing device mounted on the front plate, a first counterweight connected to the output end of the first balancing device, a second balancing device mounted on the rear plate, and a second counterweight connected to the output end of the second balancing device. When making a sharp turn, the statically unstable wheeled mobile robot of this invention generates a torque that counteracts the robot's tipping by controlling the rotation of the first and second counterweights mounted on the front and rear plates, respectively. This maintains the robot's balance during the turn, prolonging the time the robot remains in balance during the turn, thereby enabling the robot to make sharp turns with the minimum turning radius. This meets the need for efficient and flexible turning in narrow areas and effectively solves the technical problems of excessively large turning radii and unstable turning in the prior art.

Description

Technical Field

[0001] This invention relates to the technical field of two-wheeled self-balancing vehicles, and more specifically, to a statically unstable wheeled mobile robot and its control method. Background Technology

[0002] Current two-wheeled self-balancing vehicles all have their wheels arranged side-by-side. This arrangement results in vehicles with a relatively large width, making it unsuitable for agile movement in narrow areas. While existing bicycle robots have their wheels arranged front and back, they rely solely on the front wheel for steering, with the rear wheel passively turning, making them ill-suited for the efficient and flexible turning requirements in confined spaces.

[0003] Existing technology discloses an automatically controlled, dynamically balanced, two-wheeled robot, mainly comprising a front balance plate, a rear swing plate, a front idler wheel, a rear idler wheel, a lead screw, a lead screw mounting base, a lead screw motor, a geared motor, a connecting block, a sensor group, a battery pack, and a controller. This solution uses the lead screw motor to change the center of gravity of the front balance plate to achieve efficient turning and linear acceleration of the two-wheeled robot.

[0004] However, in existing two-wheeled robots, when turning, the geared motor and the lead screw motor drive the rear swing plate to tilt in the opposite direction and lock it for a period of time. During the time the lock is formed, the robot body is in a tilted state and can only maintain balance briefly. If the lock time is too long, the robot body will roll over. The geared motor and the lead screw motor need to work together to restore the robot body to the swaying and meandering forward state before the robot body rolls over in order to maintain the balance of the robot body. Therefore, the brief balance state makes the turning radius of existing two-wheeled robots too large, which makes it difficult to meet the needs of efficient and flexible turning in narrow areas. It has technical problems of excessive turning radius and unstable turning. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies, such as excessively large turning radius and unstable turning, and to provide a statically unstable wheeled mobile robot and its control method.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] A statically unstable wheeled mobile robot is provided, comprising a front plate, a rear plate rotatably connected to the front plate, wheel frames rotatably disposed on the front plate and the rear plate respectively, casters rotatably mounted on the wheel frames, a first balancing device and a first counterweight disposed on the front plate, and a second balancing device and a second counterweight disposed on the rear plate. The first balancing device can control the first counterweight to move relative to the plane of the front plate and drive the first counterweight to rotate. The second balancing device can control the second counterweight to move relative to the plane of the rear plate and drive the second counterweight to rotate. The direction of movement of the first counterweight and the second counterweight is perpendicular to the axis of rotation of the front plate relative to the rear plate.

[0008] This invention discloses a statically unstable wheeled mobile robot. Since the movement directions of a first counterweight moving relative to the front plate plane and a second counterweight moving relative to the rear plate plane are perpendicular to the rotation axis of the front plate relative to the rear plate, a first balancing device and a second balancing device control the alternating swing of the first and second counterweights. This indirectly controls the front and rear plates to repeatedly rotate back and forth relative to each other at a certain angle, allowing the robot to move in a zigzag motion to achieve a balanced state. When the robot makes a sharp turn, the relative rotation angle between the front and rear plates needs to be maintained for a certain period of time. This state is easily disturbed, causing the robot to tilt in the turning direction. During this tilting process, to maintain the robot's turning state, the second balancing device drives the first counterweight to rotate, and the fourth balancing device drives the second counterweight to rotate. The torque generated by the rotation of the first and second counterweights generates a torque that counteracts the robot's tilting, maintaining the robot's balance during the turn and extending the time of balance. This allows the robot to make sharp turns with the smallest turning radius, meeting the need for efficient and flexible turning in narrow areas, and effectively solving the technical problems of excessively large turning radii and unstable turning in existing technologies.

[0009] Furthermore, the first balancing device includes a first fixed base disposed on the front plate, a first driving device disposed on the first fixed base, and a first pendulum rod with one end connected to the output end of the first driving device. The first counterweight is rotatably connected to the other end of the first pendulum rod. The first driving device can drive the first pendulum rod to rotate around one end. The first counterweight is provided with a second driving device for driving itself to rotate relative to the first pendulum rod. By using the first driving device to drive the first pendulum rod to swing, the first counterweight rod connected to the other end of the first pendulum rod is indirectly driven to swing, thereby realizing the movement of the first counterweight relative to the front plate. This has the advantages of easy control, fast movement speed, and large inertial force. In addition, the first counterweight is provided with a second driving device for driving itself to rotate relative to the first pendulum rod, thereby realizing the rotation of the first counterweight.

[0010] Furthermore, the second balancing device includes a second fixed base disposed on the rear plate, a third drive device disposed on the second fixed base, and a second swing arm with one end connected to the output end of the third drive device. The second counterweight is rotatably connected to the other end of the second swing arm. The third drive device can drive the second swing arm to rotate around one end. The second counterweight contains a fourth drive device for driving itself to rotate relative to the second swing arm. By adopting the same structure as the first balancing device, the relative rotation of the front and rear plates is more coordinated, making it easier to control the balance of the vehicle body.

[0011] Furthermore, the second and fourth drive devices are hub motors. Hub motors are commonly used for single-wheel drive and have the characteristic of independent drive. By setting the hub motor inside the first and second counterweights to drive their rotation, it is easy to achieve independent rotation of the first and second counterweights. In addition, hub motors have fast acceleration and high speed limits, and can quickly and continuously output torque, rapidly stabilizing the vehicle body and extending the time of vehicle body balance.

[0012] Furthermore, the first and second counterweights are flywheels. Flywheels not only have the characteristic of uniform distribution of rotational inertia, but also have a large rotational inertia, making it easy to control the rotational speed and stabilize the output torque.

[0013] Furthermore, the front panel is equipped with a controller, and the front end of the front panel and the rear end of the rear panel are respectively equipped with inertial measurement units for detecting roll angle. The first drive device and the third drive device are respectively connected to a first sensor for detecting rotation angle and rotation speed. The second drive device and the fourth drive device are respectively connected to a second sensor for detecting rotation speed and rotational acceleration. The caster is connected to a third sensor for detecting rotation speed. The inertial measurement unit, the first sensor, the second sensor, and the third sensor are all signal-connected to the controller. The first drive device, the second drive device, the third drive device, and the fourth drive device are all signal-connected to the controller. The first sensors located on the first and third drive devices are used to detect their rotation angle and rotation speed, respectively, thereby monitoring the swing amplitude and swing frequency of the first and second swing arms; the second sensors located on the second and fourth drive devices are used to monitor the rotation speed and rotational acceleration of the first and second counterweights, respectively; the inertial measurement units located at the front end of the front plate and the rear end of the rear plate are used to monitor the roll angle information of the front plate relative to the rear plate, controlling their dynamic balance rotation; the third sensor located on the casters is used to monitor the rotation speed of the casters, thereby monitoring the forward speed of the vehicle body; the controller is used to make each mechanism move in coordination according to the set program or configured instructions, which has the advantages of intelligence and automation.

[0014] Furthermore, the controller is also connected to an alarm. When the controller fails to receive electrical signals from all sensors, it indicates that one or more sensors are damaged, and the controller will activate the alarm to alert the user to check for the fault.

[0015] The present invention also provides a control method for a statically unstable wheeled mobile robot, comprising:

[0016] S1. Place the robot at the critical equilibrium position and power on the robot to start it;

[0017] S2. Start the controller and check whether the inertial measurement unit, the first sensor, the second sensor, and the third sensor can operate normally. If they cannot operate normally, perform a manual inspection. If they can all operate normally, proceed to step S3.

[0018] S3. Activate the first drive device to drive the first pendulum to swing the first counterweight, and at the same time activate the third drive device to drive the second pendulum to swing the second counterweight, so that the first counterweight and the second counterweight swing alternately, thereby adjusting the horizontal balance of the front plate and the rear plate, so that the robot is in a balanced state during the meandering forward movement.

[0019] The present invention discloses a control method for a statically unstable wheeled mobile robot. The method uses a first driving device to drive the first pendulum to swing the first counterweight, and a third driving device to drive the second pendulum to swing the second counterweight. This causes the first and second counterweights to swing alternately, allowing the robot to maintain a balanced state during small-amplitude meandering forward motion. This method has the advantages of high intelligence and automation, and realizes the automatic control of a two-wheeled balance vehicle.

[0020] Further, in step S3: if the robot needs to make a sharp turn, the third sensor detects the rotational speed of the casters to determine the robot's forward speed. The controller determines whether the robot's forward speed is greater than a threshold. If it is greater than the threshold, the first drive device drives the first swing arm, and the third drive device drives the second swing arm to indirectly control the relative rotation of the front and rear plates and maintain their relative roll angle. Simultaneously, the second drive device drives the first counterweight, and the fourth drive device drives the second counterweight to rotate at the swing position, generating a torque to counteract the robot's tipping, thus maintaining the robot's overall balance and achieving a sharp turn with the minimum turning radius. Detecting the forward speed before the robot makes a sharp turn avoids a sudden decrease in speed and an increased probability of tipping due to insufficient speed. Precisely controlling the first and second counterweights to rotate at their final swing positions during the turn generates a torque to counteract tipping, enabling the robot to achieve a sharp turn with the minimum turning radius.

[0021] Furthermore, in step S3: the user can send remote parameter configuration commands to the controller to change the robot's forward speed by adjusting the swing frequency of the first drive device driving the first pendulum and the third drive device driving the second pendulum. Changing the robot's forward speed by adjusting the swing frequency of the first drive device driving the first pendulum and the third drive device driving the second pendulum has the advantages of being simple to operate and easy to control.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] The present invention discloses a statically unstable wheeled mobile robot that, when making a sharp turn, generates a torque by controlling the rotation of the first and second counterweights respectively located on the front and rear plates. This torque counteracts the robot's tipping, thereby maintaining the robot's balance during the turn and extending the time of the robot's balance during the turn. This enables the robot to make sharp turns with the minimum turning radius, meeting the need for efficient and flexible turning in narrow areas, and effectively solving the technical problems of excessively large turning radius and unstable turning in the prior art.

[0024] The present invention discloses a control method for a statically unstable wheeled mobile robot. The method uses a first driving device to drive the first pendulum to swing the first counterweight, and a third driving device to drive the second pendulum to swing the second counterweight. This causes the first and second counterweights to swing alternately, allowing the robot to maintain a balanced state during small-amplitude meandering forward motion. This method has the advantages of high intelligence and automation, and realizes the automatic control of a two-wheeled balance vehicle. Attached Figure Description

[0025] Figure 1 This is a structural schematic diagram of a statically unstable wheeled mobile robot.

[0026] Figure 2 This is a model diagram of an inverted flywheel pendulum;

[0027] Figure 3 This is a schematic diagram of the force analysis of a statically unstable wheeled mobile robot according to Embodiment 1;

[0028] Figure 4 This is a schematic diagram of the control system of a statically unstable wheeled mobile robot according to Embodiment 2;

[0029] Figure 5 This is a schematic diagram of a control method for a statically unstable wheeled mobile robot according to Embodiment 3.

[0030] In the attached diagram: 100, front plate; 200, rear plate; 300, wheel frame; 310, caster; 400, first balancing device; 410, first counterweight; 420, first fixed base; 430, first drive device; 440, first swing arm; 500, second balancing device; 510, second counterweight; 520, second fixed base; 530, third drive device; 540, second swing arm; 600, controller; 700, inertial measurement unit. Detailed Implementation

[0031] The present invention will be further described below with reference to specific embodiments. The accompanying drawings are for illustrative purposes only, representing schematic diagrams rather than actual physical objects, and should not be construed as limiting the scope of this patent. To better illustrate the embodiments of the present invention, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0032] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0033] Example 1

[0034] like Figures 1 to 3 The image shows a first embodiment of a statically unstable wheeled mobile robot according to the present invention.

[0035] A statically unstable wheeled mobile robot is provided, comprising a front plate 100, a rear plate 200 rotatably connected to the front plate 100, wheel frames 300 rotatably disposed on the front plate 100 and the rear plate 200 respectively, casters 310 rotatably mounted on the wheel frames 300, a first balancing device 400 and a first counterweight 410 disposed on the front plate 100, and a second balancing device 500 and a second counterweight 510 disposed on the rear plate 200. The first balancing device 400 can control the first counterweight 410 to move relative to the plane of the front plate 100 and drive the first counterweight 410 to rotate. The second balancing device 500 can control the second counterweight 510 to move relative to the plane of the rear plate 200 and drive the second counterweight 510 to rotate. The direction of movement of the first counterweight 410 and the second counterweight 510 is perpendicular to the axis of rotation of the front plate 100 relative to the rear plate 200. The first balancing device 400 includes a first fixed base 420 on the front plate 100, a first driving device 430 on the first fixed base 420, and a first swing arm 440 with one end connected to the output end of the first driving device 430. A first counterweight 410 is rotatably connected to the other end of the first swing arm 440. The first driving device 430 can drive the first swing arm 440 to rotate around one end. The first counterweight 410 is provided with a second driving device for driving itself to rotate relative to the first swing arm 440. The second balancing device 500 includes a second fixed base 520 on the rear plate 200, a third driving device 530 on the second fixed base 520, and a second swing arm 540 with one end connected to the output end of the third driving device 530. The second counterweight 510 is rotatably connected to the other end of the second swing arm 540. The third driving device 530 can drive the second swing arm 540 to rotate around one end. The second counterweight 510 is provided with a fourth driving device for driving itself to rotate relative to the second swing arm 540. The second and fourth drive units are hub motors. The first counterweight 410 and the second counterweight 510 are flywheels.

[0036] In this embodiment, as Figure 1As shown, since the first counterweight 410, which moves relative to the plane of the front plate 100, and the second counterweight 510, which moves relative to the plane of the rear plate 200, move in directions perpendicular to the axis of rotation of the front plate 100 relative to the rear plate 200, the first balancing device 400 and the second balancing device 500 control the first counterweight 410 and the second counterweight 510 to swing alternately, indirectly controlling the front plate 100 and the rear plate 200 to rotate back and forth relative to each other repeatedly at a certain angle, so that the robot can move forward in a zigzag motion to achieve a balanced state. When the robot makes a sharp turn, the relative rotation angle between the front plate 100 and the rear plate 200 needs to be maintained for a certain period of time. This state is very susceptible to interference, causing the robot to rotate in the opposite direction. When the robot tilts in the direction of the bend, in order to maintain the turning state of the robot body during the tilting process, the first balancing device 400 drives the first counterweight 410 to rotate and the second balancing device 500 drives the second counterweight 510 to rotate. The torque generated by the rotation of the first counterweight 410 and the second counterweight 510 will generate a force to counteract the robot's tilting, so as to maintain the robot's balance state during the turning process and prolong the balance state time of the robot during the turning process. This enables the robot to make sharp turns with the smallest turning radius, meets the needs of efficient and flexible turning in narrow areas, and effectively solves the technical problems of excessive turning radius and unstable turning in the prior art.

[0037] In this embodiment, as Figure 1 As shown, the first driving device 430 drives the first pendulum 440 to swing, which indirectly drives the first counterweight 410 connected to the other end of the first pendulum 440 to swing, thereby realizing the movement of the first counterweight 410 relative to the front plate 100. It has the advantages of easy control, fast movement speed and large inertial force. Furthermore, a second driving device is provided in the first counterweight 410 to drive itself to rotate relative to the first pendulum 440, thereby realizing the rotation of the first counterweight 410.

[0038] In this embodiment, as Figure 1 As shown, the second balancing device 500 adopts the same structure as the first balancing device 400, which makes the relative rotation of the front and rear plates 200 more coordinated and easier to control the balance of the vehicle body.

[0039] In this embodiment, the flywheel balancing principle is as follows: Figure 2 As shown, M f M represents the torque output by the hub motor to the flywheel. m m is the reaction torque generated by the hub motor on the rocker arm. f g is the force of gravity acting on the swing arm from the flywheel and hub motor, m p g is the weight of the pendulum itself, N is the supporting force of the ground on the fulcrum of the pendulum, θ is the tilt angle of the pendulum, and L is the length of the pendulum.

[0040] For equilibrium to be achieved, the net external force ∑F = 0, and the net external torque ∑M = 0 must also be satisfied.

[0041] Taking the pendulum as the research object:

[0042] Nm p gm f g = 0, satisfying ∑F = 0

[0043] M m -1 / 2L·m p g·cosθ-L·m f g·cosθ=0, satisfying ∑M=0

[0044] That is, the system can be balanced by the torque M of the hub motor.

[0045] Similarly, such as Figure 3 As shown, in this invention, the tilt can also be maintained at a certain angle by the reaction torque of the flywheel on the motor: M f M is the torque output by the fourth drive unit to the second counterweight 510. m m is the reaction torque generated by the fourth drive unit on the robot. f g is the force exerted on the robot by the second counterweight 510 and the fourth drive device, m p g is the overall weight of the robot, N is the supporting force of the ground on the caster 310, θ is the tilt angle of the second swing arm 540, and L is the length of the second swing arm 540.

[0046] For equilibrium to be achieved, the net external force ∑F = 0, and the net external torque ∑M = 0 must also be satisfied.

[0047] Taking the robot as a whole as the research object:

[0048] Nm p gm f g = 0, satisfying ∑F = 0

[0049] M m -1 / 2L·m p g·cosθ-L·m f g·cosθ=0, satisfying ∑M=0

[0050] That is, the torque M output by the fourth drive unit can balance the tilted vehicle body.

[0051] In addition, in this embodiment, the first balancing device 400 may also use a motor mounted on the front plate 100, with the output shaft of the motor connected to a lead screw to drive the lead screw to rotate, and the first counterweight 410 threadedly connected to the lead screw, and the forward and reverse rotation of the motor realizes the movement of the first counterweight 410 relative to the front plate 100.

[0052] In addition, in this embodiment, the second balancing device 500 can also be a motor mounted on the rear plate 200, with the output shaft of the motor connected to a lead screw to drive the lead screw to rotate, and the second counterweight 510 threadedly connected to the lead screw. The forward and reverse rotation of the motor realizes the movement of the first counterweight 410 relative to the rear plate 200.

[0053] In this embodiment, the hub motor is commonly used for driving a single wheel and has the characteristic of independent driving. The hub motor is set in the first counterweight 410 and the second counterweight 510 to drive them to rotate, which facilitates the independent rotation of the first counterweight 410 and the second counterweight 510. In addition, the hub motor accelerates quickly and has a high speed limit, which can output torque quickly and continuously, stabilize the vehicle body quickly and extend the time of vehicle body balance.

[0054] In this embodiment, the flywheel not only has the characteristic of uniform distribution of rotational inertia, but also has a large rotational inertia, making it easy to control the speed and stabilize the output torque.

[0055] Example 2

[0056] like Figure 1 and Figure 4 The image shows a second embodiment of a statically unstable wheeled mobile robot according to the present invention.

[0057] This embodiment is similar to Embodiment 1 or Embodiment 2, except that: the front panel 100 is equipped with a controller 600, and the front end of the front panel 100 and the rear end of the rear panel 200 are respectively equipped with inertial measurement units 700 for detecting roll angle. The first drive device 430 and the third drive device 530 are respectively connected to first sensors for detecting rotation angle and rotational speed. The second drive device and the fourth drive device are respectively connected to second sensors for detecting rotational speed and rotational acceleration. The caster 310 is connected to a third sensor for detecting rotational speed. The inertial measurement unit 700, the first sensor, the second sensor, and the third sensor are all signal-connected to the controller 600. The first drive device 430, the second drive device, the third drive device 530, and the fourth drive device are all signal-connected to the controller 600. An alarm is also signal-connected to the controller 600.

[0058] In this embodiment, as Figure 1 and Figure 4As shown, the first sensors located on the first drive device 430 and the third drive device 530 are used to detect their rotation angle and rotation speed, respectively, thereby monitoring the swing amplitude and swing frequency of the first swing arm 440 and the second swing arm 540; the second sensors located on the second drive device and the fourth drive device are used to monitor the rotation speed and rotational acceleration of the first counterweight 410 and the second counterweight 510, respectively; the inertial measurement units 700 located at the front end of the front plate 100 and the rear end of the rear plate 200 are used to monitor the roll angle information of the front plate 100 relative to the rear plate 200, and control the dynamic balance rotation of the two; the third sensor located on the caster 310 is used to monitor the rotation speed of the caster 310, thereby monitoring the forward speed of the vehicle body; the controller 600 is used to make each mechanism cooperate and move according to the set program or configured instructions, which has the advantages of intelligence and automation.

[0059] Furthermore, in this embodiment, the first sensor, the second sensor, and the third sensor are all encoders. The encoder is mainly used to measure the speed, acceleration, position, angle, distance, or angular displacement of mechanical motion so that the motor can detect commutation, speed, and position, which facilitates the control of the robot's balance.

[0060] In this embodiment, when the controller 600 fails to receive electrical signals from all sensors, it means that one or more sensors are damaged, and the controller will activate the alarm to remind the user to check for the fault.

[0061] Example 3

[0062] like Figure 5 The figure shown is an embodiment of a statically unstable wheeled mobile robot and its control method according to the present invention.

[0063] A statically unstable wheeled mobile robot and its control method thereof, comprising:

[0064] S1. Place the robot at the critical equilibrium position and power on the robot to start it;

[0065] S2. Start the controller 600 and check whether the inertial measurement unit 700, the first sensor, the second sensor, and the third sensor can operate normally. If they cannot operate normally, perform a manual inspection; if they can all operate normally, proceed to step S3.

[0066] S3. Start the first drive device 430 to drive the first swing arm 440 to swing the first counterweight 410. At the same time, start the third drive device 530 to drive the second swing arm 540 to swing the second counterweight 510, so that the first counterweight 410 and the second counterweight 510 swing alternately, thereby adjusting the horizontal balance of the front plate 100 and the rear plate 200, so that the robot is in a balanced state during the meandering forward motion.

[0067] S4. If the controller 600 receives a parameter configuration instruction, it can change the robot's forward speed by adjusting the swing frequency of the first drive device 430 driving the first pendulum 440 and the third drive device 530 driving the second pendulum 540; if the controller 600 does not receive a parameter configuration instruction, proceed to step S5.

[0068] S5. If the controller 600 receives a motion control command, it can adjust the swing amplitude of the first pendulum 440 driven by the first drive device 430 relative to the second pendulum 540 driven by the third drive device 530 to realize the motion control operation of the robot turning left and right; if the controller 600 does not receive a motion control command, it will proceed to step S6.

[0069] S6. If the controller 600 does not receive any control commands, the robot will return to the balanced state of meandering forward in step S3; if the controller 600 receives a power-off command, the operation can be terminated by powering off the power.

[0070] In S5: If the robot needs to make a sharp turn, the third sensor detects the rotation speed of the caster 310 to obtain the robot's forward speed. The controller 600 determines whether the robot's forward speed is greater than a threshold. If it is greater than the threshold, the first drive device 430 drives the first swing arm 440 and the third drive device 530 drives the second swing arm 540 to indirectly control the relative rotation of the front plate 100 and the rear plate 200 and maintain the relative roll angle. At the same time, the second drive device drives the first counterweight 410 and the fourth drive device drives the second counterweight 510 to rotate at the swing position to generate a force to counteract the robot's tipping, so as to maintain the overall balance of the robot and achieve a sharp turn with the minimum turning radius.

[0071] In this embodiment, as Figure 5 As shown, when the robot starts up and does not receive any control commands, it will remain in a balanced state by moving forward in a small amplitude meandering motion. Users can send remote parameter configuration commands to the controller 600 to make the robot perform complex actions such as acceleration, left turn, or right turn. The relative position of the front and rear plates 200 can be represented by a sine function, such as Asinwx+B, where A is the amplitude, w is the angular frequency, and B is the offset. The amplitude determines the movement amplitude of the front and rear plates 200, the angular frequency indirectly determines the robot's movement speed, and the offset determines the turning amplitude. This enables parameter configuration, has high intelligence and automation, and meets the needs of efficient and flexible movement in narrow areas.

[0072] In this embodiment, as Figure 5As shown, the robot detects its forward speed before making a sharp turn to avoid the vehicle body making a sharp turn when the speed is insufficient, which would cause a sudden decrease in speed and an increased probability of tipping over. It also precisely controls the first counterweight 410 and the second counterweight 510 to rotate at the last swing position during the turn, so as to generate a force to counteract the tipping over the torque output of the entire vehicle body, enabling the robot to make a sharp turn with the smallest turning radius.

[0073] Furthermore, in this embodiment, such as Figure 4 As shown, the controller 600 uses STMicroelectronics' STM32F4 microcontroller, which has the advantages of high integration and fast response speed.

[0074] In the specific implementation of the above embodiments, the technical features can be combined in any non-contradictory way. For the sake of brevity, not all possible combinations of the above technical features are described. However, as long as the combination of these technical features is not contradictory, it should be considered to be within the scope of this specification.

[0075] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A statically unstable wheeled mobile robot, characterized in that: The system includes a front plate (100), a rear plate (200) rotatably connected to the front plate (100), wheel frames (300) rotatably mounted on the front plate (100) and the rear plate (200), casters (310) rotatably mounted on the wheel frames (300), a first balancing device (400) and a first counterweight (410) mounted on the front plate (100), and a second balancing device (500) and a second counterweight (510) mounted on the rear plate (200). (400) can control the first counterweight (410) to move relative to the front plate (100) plane and drive the first counterweight (410) to rotate, and the second balancing device (500) can control the second counterweight (510) to move relative to the rear plate (200) plane and drive the second counterweight (510) to rotate, and the moving direction of the first counterweight (410) and the second counterweight (510) is perpendicular to the rotation axis of the front plate (100) relative to the rear plate (200); The first balancing device (400) includes a first driving device (430) and a first pendulum (440) with one end connected to the output end of the first driving device (430). The first counterweight (410) is rotatably connected to the other end of the first pendulum (440). The first driving device (430) can drive the first pendulum (440) to rotate around one end. The first counterweight (410) is provided with a second driving device for driving itself to rotate relative to the first pendulum (440). The second balancing device (500) includes a third driving device (530) and a second pendulum (540) with one end connected to the output end of the third driving device (530). The second counterweight (510) is rotatably connected to the other end of the second pendulum (540). The third driving device (530) can drive the second pendulum (540) to rotate around one end. The second counterweight (510) is provided with a fourth driving device for driving itself to rotate relative to the second pendulum (540). The front plate (100) is provided with a controller (600). The front end of the front plate (100) and the rear end of the rear plate (200) are respectively provided with inertial measurement units (700) for detecting roll angle. The first drive device (430) and the third drive device (530) are respectively connected to a first sensor for detecting rotation angle and rotation speed. The second drive device and the fourth drive device are respectively connected to a second sensor for detecting rotation speed and rotational acceleration. The caster (310) is connected to a third sensor for detecting rotation speed. The inertial measurement unit (700), the first sensor, the second sensor and the third sensor are all signal-connected to the controller (600). The first drive device (430), the second drive device, the third drive device (530) and the fourth drive device are all signal-connected to the controller (600).

2. The statically unstable wheeled mobile robot according to claim 1, characterized in that: The first balancing device (400) further includes a first fixed base (420) disposed on the front plate (100), and the first driving device (430) is disposed on the first fixed base (420).

3. A statically unstable wheeled mobile robot according to claim 2, characterized in that: The second balancing device (500) further includes a second fixed base (520) disposed on the rear plate (200), and the third driving device (530) is disposed on the second fixed base (520).

4. A statically unstable wheeled mobile robot according to claim 3, characterized in that: The second drive device and the fourth drive device are hub motors.

5. A statically unstable wheeled mobile robot according to claim 1, characterized in that: The first counterweight (410) and the second counterweight (510) are flywheels.

6. A statically unstable wheeled mobile robot according to claim 1, characterized in that: The controller (600) is also connected to an alarm.

7. A control method for a statically unstable wheeled mobile robot, used to control a statically unstable wheeled mobile robot as described in any one of claims 1-6, characterized in that, include: S1. Place the robot at the critical equilibrium position and power on the robot to start it; S2. Start the controller (600) and check whether the inertial measurement unit (700), the first sensor, the second sensor and the third sensor can operate normally. If they cannot operate normally, perform a manual inspection. If they can all operate normally, proceed to step S3. S3. Start the first drive device (430) to drive the first pendulum (440) to swing the first counterweight (410), and at the same time start the third drive device (530) to drive the second pendulum (540) to swing the second counterweight (510), so that the first counterweight (410) and the second counterweight (510) swing alternately, thereby adjusting the horizontal balance of the front plate (100) and the rear plate (200) so that the robot is in a balanced state during the meandering forward movement; In step S3: If the robot needs to make a sharp turn, the rotation speed of the caster (310) is detected by the third sensor to obtain the forward speed of the robot. The controller (600) determines whether the forward speed of the robot is greater than the threshold. If it is greater than the threshold, the first drive device (430) drives the first swing arm (440) and the third drive device (530) drives the second swing arm (540) to indirectly control the relative rotation of the front plate (100) and the rear plate (200) and maintain the relative roll angle. At the same time, the second drive device drives the first counterweight (410) and the fourth drive device drives the second counterweight (510) to rotate at the swing position to generate a torque to counteract the tipping of the robot, so as to maintain the overall balance of the robot and achieve a sharp turn with the minimum turning radius.

8. The control method for a statically unstable wheeled mobile robot according to claim 7, characterized in that, In step S3: The user can send a remote parameter configuration command to the controller (600) to change the robot's forward speed by adjusting the swing frequency of the first drive device (430) driving the first pendulum (440) and the third drive device (530) driving the second pendulum (540).

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