Trackless Two-Wheel Robot Applicable to Multiple Terrains and Trackless Two-Wheel Robot Control Method

Abstract

Borderless two-wheeled robot applicable to multiple terrains and control method thereof. The present invention relates to a borderless two-wheeled robot and a control method thereof. The purpose of the present invention is to solve the problems that the existing borderless two-wheeled robot has an underactuated structure and cannot maintain stability when dealing with external disturbances such as road bumps and is prone to tipping over; and the borderless two-wheeled robot also has difficulties in starting from a standstill. The borderless two-wheeled robot applicable to multiple terrains includes a central platform, an angle control module, borderless wheels, a pendulum, and a control circuit; an angle control module is installed on each side of the central platform; a borderless wheel is installed on each of the two angle control modules; the pendulum is installed at the bottom or front of the central platform. The control process of the control method for the borderless two-wheeled robot applicable to multiple terrains is as follows: The control of the borderless two-wheeled robot is divided into the control of the starting stage, the forward stage, and the turning stage. The present invention is used in the technical field of borderless wheel vehicles.

Description

Technical Field

[0001] The present invention relates to the technical field of rimless wheel vehicles, in particular to a rimless two-wheel robot and a control method for the rimless two-wheel robot. Background Art

[0002] The rimless wheel is a commonly used structure in scientific research, but it is less applied in actual industrial production. This is mainly because the rimless two-wheel robot is an underactuated structure and cannot maintain stability when dealing with external disturbances such as road bumps, and is prone to tipping over.

[0003] In addition, the rimless two-wheel robot also has the problem of difficult starting from a standstill. Currently, the method of starting in a suspended state and then placing it on the ground is usually adopted to avoid this problem, which is not conducive to the quick start of the rimless two-wheel robot.

[0004] Therefore, it is crucial to develop a new type of rimless two-wheel robot applicable to multiple terrains and a control method for the rimless two-wheel robot. Summary of the Invention

[0005] The purpose of the present invention is to solve the problems that the existing rimless two-wheel robot is an underactuated structure and cannot maintain stability when dealing with external disturbances such as road bumps and is prone to tipping over; and the rimless two-wheel robot also has the problem of difficult starting from a standstill, and to propose a rimless two-wheel robot applicable to multiple terrains and a control method for the rimless two-wheel robot.

[0006] A rimless two-wheel robot applicable to multiple terrains, the rimless two-wheel robot includes a central platform 1, an angle control module 2, rimless wheels 3, a pendulum 4, and a control circuit;

[0007] One angle control module 2 is installed on each side of the central platform 1;

[0008] One rimless wheel 3 is installed on each of the two angle control modules 2;

[0009] The pendulum 4 is installed at the bottom or front of the central platform 1.

[0010] Preferably, the central platform 1 includes a plurality of screw holes and a platform for installing the angle control module 1 and the pendulum 4.

[0011] Preferably, the angle control module 2 includes a motor 2-1, a connecting member 2-2 connected to the central platform, and a connecting member 2-3 connected to the rimless wheel;

[0012] One end of the connecting member 2-2 connected to the central platform is fixed to the central platform 1, and the other end of the connecting member 2-2 connected to the central platform is fixed to one side of the motor 2-1.

[0013] Preferably, the borderless wheel 3 includes a motor 3-1, a wheel disc 3-2, legs 3-3, and a shock absorber 3-4;

[0014] The motor 3-1 is installed on the wheel disc 3-2;

[0015] The legs 3-3 are evenly installed circumferentially under the wheel disc 3-2;

[0016] The motor 3-1, the wheel disc 3-2, and the legs 3-3 are coaxially arranged;

[0017] The motor 3-1 controls the swinging of the legs 3-3;

[0018] The shock absorber 3-4 is located on the legs 3-3.

[0019] Preferably, one end of the connecting member 2-3 connected to the borderless wheel is fixed to the motor 3-1 of the borderless wheel, and the other end of the connecting member 2-3 connected to the borderless wheel is fixed to one side of the motor 2-1 of the angle control module.

[0020] Preferably, the pendulum 4 includes a frame 4-1, a counterweight 4-2, an auxiliary wheel 4-3, a connecting member 4-5 connected to the central platform, and a motor 4-4 for controlling the inclination angle of the pendulum between the frame 4-1 and the connecting member 4-5;

[0021] The counterweight 4-2 is installed at the lower part or the front part of the frame 4-1, and the auxiliary wheel 4-3 is installed at the tail of the frame 4-1.

[0022] The control process of the control method for the borderless two-wheel robot applicable to multiple terrains is as follows:

[0023] The control of the borderless two-wheel robot is divided into the control of the starting stage, the forward stage, and the turning stage.

[0024] Preferably, the specific process of the starting stage is as follows:

[0025] Step 1: The angle control module 2 of the borderless two-wheel robot controls the borderless wheel 3 to be perpendicular or non-perpendicular to the ground;

[0026] Step 2: The motors 3-1 of the two borderless wheels 3 rotate forward simultaneously to generate a backward moment on the central platform 1;

[0027] Step 3: Under the action of the backward moment generated on the central platform 1, the pendulum 4 is lifted until the auxiliary wheel 4-3 of the pendulum 4 touches the ground;

[0028] Step 4: After the auxiliary wheel 4-3 touches the ground, the borderless two-wheel robot starts to move forward, and the central platform 1 maintains horizontal under the control of the control circuit, and the auxiliary wheel 4-3 leaves the ground;

[0029] In step 4, the central platform 1 maintains horizontal under the control of the control circuit; the specific process is as follows:

[0030] The control circuit first reads the data of the inertial measurement unit installed on the central platform 1 to obtain the pitch angle of the central platform 1.

[0031] Calculate the deviation value between the measured pitch angle value of the central platform 1 and the expected pitch angle of 0°, and perform PID control based on the deviation value to output the control quantity.

[0032] Superimpose the PID control output control quantity and the rotational speed quantity of the motor of the borderless wheel 3 itself to control the central platform 1 to maintain horizontal.

[0033] When the deviation value is less than ±5°, the central platform 1 is not controlled.

[0034] Preferably, the control process in the forward stage is as follows:

[0035] The control of the borderless two-wheeled robot in the forward stage is divided into the control of the pendulum 4 and the control of the angle control module 2; A. The control process of the pendulum 4 is as follows:

[0036] When the borderless two-wheeled robot has a tendency to tilt to one side;

[0037] The control circuit first reads the data of the inertial measurement unit installed on the central platform 1 to obtain the roll angle of the central platform 1.

[0038] Calculate the deviation value between the measured roll angle value and the expected roll angle of 0°, and perform PID control based on the deviation value to output the control quantity.

[0039] Apply the PID control output control quantity to the pendulum 4 to control the speed of the pendulum 4, and complete the roll angle of the central platform 1 of the borderless two-wheeled robot to remain horizontal with the ground.

[0040] When the pendulum 4 swings to the angle limit, the pendulum 4 returns to the center position at a low speed.

[0041] B. The control process of the angle control module 2 is as follows:

[0042] The angle control module 2 of the borderless two-wheeled robot controls the borderless wheel 3 to be perpendicular or not perpendicular to the ground according to the terrain; the specific process is as follows:

[0043] The control circuit first reads the data of the inertial measurement unit installed on the central platform 1 to obtain the roll angle of the central platform 1.

[0044] Take the central platform 1 parallel to the ground as 0°.

[0045] When the roll angle of the central platform 1 is greater than ±15° and the duration is greater than three seconds, the control circuit determines that the current road is a bumpy road surface, and automatically rotates the angle control modules on both sides to lower the center of gravity of the borderless two-wheeled robot body.

[0046] When the roll angle of the central platform module is less than or equal to ±15° and the duration is greater than three seconds, the control circuit determines that the current road surface is flat, and automatically rotates the angle control modules 2 on both sides to complete the control of the angle control module 2 to make the trackless wheels 3 perpendicular to the ground.

[0047] Preferably, the control process in the steering stage is as follows:

[0048] The control of the trackless two-wheel robot in the steering stage is divided into the control of the pendulum 4 and the control of the angle control module 2;

[0049] A. The control process of the pendulum 4 is as follows:

[0050] When the trackless two-wheel robot has a tendency to tilt to one side, the control circuit first reads the data of the inertial measurement unit installed on the central platform 1 to obtain the roll angle of the central platform 1;

[0051] Calculate the deviation value between the obtained roll angle measurement value and the expected roll angle of 0°, and perform PID control based on the deviation value to output the control quantity;

[0052] Apply the PID control output control quantity to the pendulum 4 to control the speed of the pendulum 4, and complete the roll angle of the central platform module 1 of the trackless two-wheel robot to remain horizontal with the ground;

[0053] When the pendulum 4 swings to the angle limit, the pendulum 4 returns to the central position at a low speed;

[0054] B. The control process of the angle control module 2 is as follows:

[0055] 1. The motors of the two trackless wheels 3 change their speeds to generate a speed difference to complete the steering;

[0056] 2. When the trackless two-wheel robot turns to one side, the control circuit will make the angle control module 2 on that side control the trackless wheel 3 to tilt according to the steering direction to lower the body center of gravity of the trackless two-wheel robot;

[0057] When the trackless two-wheel robot finishes turning, the control circuit will make the angle control module 2 on that side control the trackless wheel not to tilt, so that the body center of gravity of the trackless two-wheel robot is restored.

[0058] The beneficial effects of the present invention are as follows:

[0059] The angle control module enhances the stability of the trackless two-wheel robot. When the trackless two-wheel robot passes through a flat road surface, the angle control module can make the trackless wheels perpendicular to the ground, with a small body width and flexible movement; when the trackless two-wheel robot passes through a rough road surface, the angle control module can make the trackless wheels form a V shape to lower the center and increase the width to avoid tipping.

[0060] The pendulum module makes it easier for the tireless two - wheel robot to start from a standstill. When the robot is stationary on the ground, the torque required for the tireless wheel motor at the moment of startup is greater than that during normal operation. Therefore, problems such as bouncing and tipping over are likely to occur during the startup. The auxiliary wheel at the tail of the pendulum module can support the ground when the robot starts from a standstill, preventing the robot from bouncing and tipping over.

[0061] The pendulum module enhances the stability of the tireless two - wheel robot. When the body of the robot shows a tendency to tip over, the pendulum can swing actively in the opposite direction, using the torque generated by its own weight around the support feet of the tireless wheels to right itself, thus enhancing the stability of the robot.

[0062] The pendulum module makes the tireless two - wheel robot more efficient. When the two tireless wheels rotate forward, they generate a backward torque on the central module. The center of gravity of the pendulum module is in front of the central module, and the gravity of the pendulum can be used to offset part of the backward torque. Further, if the payload is arranged on the pendulum, the backward torque can be used to support the payload, achieving higher efficiency. Description of the Drawings

[0063] Figure 1 It is a schematic diagram of the overall structure of the tireless two - wheel robot of the present invention;

[0064] Figure 2 It is a schematic diagram of the central module;

[0065] Figure 3 It is a schematic diagram of the angle control module;

[0066] Figure 4 It is a schematic diagram of the tireless wheel;

[0067] Figure 5 It is a schematic diagram of the pendulum module;

[0068] Figure 6 It is a schematic diagram of the working state of the pendulum module;

[0069] Figure 7 It is a schematic diagram of the working state of the angle control module. Detailed Embodiments

[0070] Detailed Embodiment 1: This embodiment is applicable to tireless two - wheel robots in various terrains. The tireless two - wheel robot includes a central platform 1, an angle control module 2, tireless wheels 3, a pendulum 4, and a control circuit;

[0071] One angle control module 2 is installed on each side of the central platform 1;

[0072] One tireless wheel 3 is installed on each of the two angle control modules 2;

[0073] The pendulum 4 is installed at the bottom or front of the central platform 1.

[0074] Specific Embodiment 2: The difference between this embodiment and Specific Embodiment 1 is that: the central platform 1 includes a number of screw holes and a platform for installing the angle control module 1 and the pendulum 4.

[0075] Other steps and parameters are the same as those in Specific Embodiment 1.

[0076] Specific Embodiment 3: The difference between this embodiment and Specific Embodiment 1 or 2 is that: the angle control module 2 includes a motor 2-1, a connector 2-2 connected to the central platform, and a connector 2-3 connected to the endless wheel;

[0077] One end of the connector 2-2 connected to the central platform is fixed on the central platform 1, and the other end of the connector 2-2 connected to the central platform is fixed on one side of the motor 2-1.

[0078] Other steps and parameters are the same as those in Specific Embodiment 1 or 2.

[0079] Specific Embodiment 4: The difference between this embodiment and any one of Specific Embodiments 1 to 3 is that: the endless wheel 3 includes a motor 3-1, a wheel disc 3-2, a number of legs 3-3, and an optional shock absorber 3-4;

[0080] The motor 3-1 is installed on the wheel disc 3-2;

[0081] The legs 3-3 are evenly installed circumferentially under the wheel disc 3-2;

[0082] The motor 3-1, the wheel disc 3-2, and the legs 3-3 are coaxially arranged;

[0083] The motor 3-1 controls the swinging of the legs 3-3);

[0084] The shock absorber 3-4 is located on the legs 3-3.

[0085] Other steps and parameters are the same as those in any one of Specific Embodiments 1 to 3.

[0086] Specific Embodiment 5: The difference between this embodiment and any one of Specific Embodiments 1 to 4 is that: one end of the connector 2-3 connected to the endless wheel is fixed on the motor 3-1 of the endless wheel, and the other end of the connector 2-3 connected to the endless wheel is fixed on one side of the motor 2-1 of the angle control module, and this side is different from the side of the connector 2-2 connected to the central platform.

[0087] Other steps and parameters are the same as those in any one of Specific Embodiments 1 to 4 to 1.

[0088] Embodiment Six: The difference between this embodiment and any one of Embodiments One to Five is that the pendulum 4 includes a frame 4-1, a counterweight 4-2, one or several auxiliary wheels 4-3, one or several connectors 4-5 connected to the central platform, and one or several motors 4-4 for controlling the inclination angle of the pendulum and connecting the frame 4-1 and the connector 4-5;

[0089] The counterweight 4-2 is installed at the lower part or the front part of the frame 4-1, and the auxiliary wheels 4-3 are installed at the tail of the frame 4-1.

[0090] Other steps and parameters are the same as those in any one of Embodiments One to Five.

[0091] Embodiment Seven: The control process of the control method for the borderless two-wheeled robot applicable to multiple terrains is as follows:

[0092] The control of the borderless two-wheeled robot is divided into the control of the starting stage, the forward stage, and the turning stage.

[0093] Embodiment Eight: The difference between this embodiment and Embodiment Seven is that the specific process of the starting stage is as follows:

[0094] Step 1: The angle control module 2 of the borderless two-wheeled robot controls the borderless wheels 3 to be perpendicular or non-perpendicular to the ground according to the terrain of the starting area, as Figure 7 shown;

[0095] Step 2: The motors 3-1 of the two borderless wheels (3) rotate forward simultaneously to generate a backward torque on the central platform (1);

[0096] Step 3: Under the action of the backward torque generated on the central platform 1, the pendulum 4 is lifted until the auxiliary wheels 4-3 of the pendulum 4 touch the ground;

[0097] Step 4: After the auxiliary wheels 4-3 touch the ground, the borderless two-wheeled robot starts to move forward. The central platform 1 maintains a horizontal state under the control of the control circuit (the upper plane of the pendulum module is parallel to the ground), and the auxiliary wheels 4-3 leave the ground;

[0098] In Step 4, the central platform 1 maintains a horizontal state under the control of the control circuit; the specific process is as follows:

[0099] In order to keep the pitch angle of the central platform (1) of the borderless two-wheeled robot horizontal with the ground, the control circuit first reads the data of the inertial measurement unit (IMU) installed on the central platform 1 to obtain the pitch angle of the central platform 1;

[0100] Calculate the deviation value between the measured pitch angle of the central platform 1 and the expected pitch angle of 0°, and perform PID control based on the deviation value to output a control quantity (input the deviation value into the proportional controller, derivative controller, and integral controller respectively. The control quantities output by the three controllers are each multiplied by a proportional coefficient, and then added together to obtain the PID control output control quantity);

[0101] Superimpose the PID control output control quantity and the rotational speed of the motor of the trackless wheel 3 itself to control the central platform 1 to maintain horizontal;

[0102] In addition, set a dead zone for pitch angle control. When the deviation value is less than ±5°, the central platform 1 is not controlled to avoid high-frequency oscillation of the central module.

[0103] When the motor rotates forward, it drives the central platform module to rotate backward so that the auxiliary wheel touches the ground. After the auxiliary wheel touches the ground and cannot rotate anymore, the two trackless wheels start to rotate.

[0104] Other steps and parameters are the same as those in the seventh specific implementation manner.

[0105] Specific implementation manner nine: The difference between this implementation manner and the seventh or eighth specific implementation manner is that the control process of the trackless double-wheel robot in the forward stage is as follows:

[0106] The control of the trackless double-wheel robot in the forward stage is divided into the control of the pendulum 4 and the control of the angle control module 2; A. The control process of the pendulum 4 is as follows:

[0107] When the trackless double-wheel robot has a tendency to tilt to one side, the pendulum module swings to the other side to keep the robot running stably, as Figure 6 shown;

[0108] In order to keep the roll angle of the central platform module 1 of the trackless double-wheel robot horizontal with the ground, the control circuit first reads the data of the inertial measurement unit (IMU) installed on the central platform 1 to obtain the roll angle of the central platform 1;

[0109] Calculate the deviation value between the measured roll angle and the expected roll angle of 0°, and perform PID control based on the deviation value to output a control quantity (input the deviation value into the proportional controller, derivative controller, and integral controller respectively. The control quantities output by the three controllers are each multiplied by a proportional coefficient, and then added together to obtain the PID control output control quantity);

[0110] Apply the PID control output control quantity to the pendulum 4 to control the speed of the pendulum 4, and complete the horizontal maintenance of the roll angle of the central platform 1 of the trackless double-wheel robot;

[0111] When the pendulum 4 swings to the angle limit, the pendulum 4 returns to the central position at a low speed (the lowest speed of the motor (4-4) that controls the pendulum inclination);

[0112] B. The control process of the angle control module 2 is as follows:

[0113] The angle control module 2 of the borderless two-wheel robot controls the borderless wheels 3 to be perpendicular or non-perpendicular to the ground according to the terrain, as Figure 7 shown; the specific process is as follows:

[0114] The control circuit first reads the data of the inertial measurement unit (IMU) installed on the central platform 1 to obtain the roll angle of the central platform 1.

[0115] Taking the central platform 1 parallel to the ground as 0°.

[0116] When the roll angle of the central platform 1 is greater than ±15° and the duration is greater than three seconds, the control circuit determines that the current road is a bumpy road surface and automatically rotates the angle control modules on both sides to lower the center of gravity of the borderless two-wheel robot body (the tilt angle of the borderless wheels is 30°), as Figure 7 shown.

[0117] When the roll angle of the central platform module is less than or equal to ±15° and the duration is greater than three seconds, the control circuit determines that the current road is a flat road surface and automatically rotates the angle control modules 2 on both sides to complete the control of the angle control module 2 to make the borderless wheels 3 perpendicular to the ground (raising the center of gravity of the body).

[0118] Other steps and parameters are the same as those in the seventh or eighth specific implementation manner.

[0119] Specific implementation manner ten: The difference between this implementation manner and one of the seventh to ninth specific implementation manners is that the control process of the borderless two-wheel robot during the turning stage is as follows:

[0120] The control of the borderless two-wheel robot during the turning stage is divided into the control of the pendulum 4 and the control of the angle control module 2;

[0121] A. The control process of the pendulum 4 is as follows:

[0122] When the borderless two-wheel robot has a tendency to tilt to one side, the pendulum module swings to the other side to keep the robot running stably, as Figure 6 shown; in order to keep the roll angle of the central platform module (1) of the borderless two-wheel robot horizontal with the ground, the control circuit first reads the data of the inertial measurement unit (IMU) installed on the central platform 1 to obtain the roll angle of the central platform 1.

[0123] Calculate the deviation value between the obtained roll angle measurement value and the expected roll angle of 0°, and perform PID control based on the deviation value to output the control quantity (input the deviation value into the proportional controller, derivative controller, and integral controller respectively. The control quantities output by the three controllers are each multiplied by a proportional coefficient, and then added together to obtain the PID control output control quantity);

[0124] Apply the PID control output control quantity to the pendulum 4 to control the speed of the pendulum 4, and complete the horizontal alignment of the roll angle of the central platform module 1 of the tireless two-wheeled robot with the ground;

[0125] When the pendulum 4 swings to the angle limit, the pendulum 4 returns to the central position at a low speed (the lowest speed of the motor 4-4 that controls the inclination angle of the pendulum);

[0126] B. The control process of the angle control module 2 is as follows:

[0127] I. The motors of the two tireless wheels 3 change their speeds to generate a speed difference to complete the turning (for example, when going straight, the speeds of the left and right tireless wheels are both 3000, then when turning left, the left wheel is 2900 and the right wheel is 3100);

[0128] II. When the tireless two-wheeled robot turns to a certain side, the control circuit will make the angle control module 2 on that side control the tireless wheel 3 to tilt according to the turning direction, reducing the center of gravity of the body of the tireless two-wheeled robot (the tilt angle of the tireless wheel is 30°), as Figure 7 shown; when turning left, the left tireless wheel tilts at a certain angle;

[0129] When the tireless two-wheeled robot finishes turning, the control circuit will make the angle control module 2 on that side control the tireless wheel not to tilt (perpendicular to the ground), so that the center of gravity of the body of the tireless two-wheeled robot is restored (the tilt angle of the tireless wheel is 0°).

[0130] Other steps and parameters are the same as those in one of Embodiments Seven to Nine.

[0131] Working principle:

[0132] At the starting stage, manually set the two tireless wheels of the tireless two-wheeled robot to be perpendicular or not perpendicular to the ground, and issue a start command. The two-wheel motors of the tireless two-wheeled robot start to rotate, driving the central platform and the pendulum to lift up until the pendulum auxiliary wheel touches the ground. The two tireless wheels start to rotate, and the tireless two-wheeled robot starts to move forward. The central platform is adjusted to be horizontal under the control of the control circuit, and at this time the pendulum auxiliary wheel leaves the ground.

[0133] During the straight-line stage, the two borderless wheels of the borderless two-wheeled robot rotate at the same speed to drive the borderless two-wheeled robot to move straight forward. When encountering external factors that cause bumps in the operation of the borderless two-wheeled robot, the control circuit controls the pendulum to swing in the opposite direction to maintain the horizontal roll angle of the central platform; when the borderless two-wheeled robot experiences continuous bumps, the control circuit controls the angle control module to rotate the two borderless wheels to lower the body center of gravity and ensure stable operation. After the continuous bumps disappear, the control circuit controls the angle control module to rotate the two borderless wheels to restore the body center of gravity.

[0134] During the turning stage, the two borderless wheel motors of the borderless two-wheeled robot accelerate on one side and decelerate on the other side, and use differential speed to turn. The control circuit will cause the angle control module on that side to control the inclination of the borderless wheel according to the turning direction to lower the body center of gravity of the borderless two-wheeled robot for easy turning.

[0135] The present invention may also have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention. However, these corresponding changes and deformations should all fall within the protection scope of the appended claims of the present invention.

Claims

1. An endless two-wheel robot control method applicable to multiple terrains, the endless two-wheel robot comprising a central platform (1), an angle control module (2), endless wheels (3), a pendulum (4), and a control circuit; an angle control module (2) is installed on each side of the central platform (1); an endless wheel (3) is installed on each of the two angle control modules (2); a pendulum (4) is installed at the bottom or front of the central platform (1); the central platform (1) comprises a plurality of screw holes and a platform for installing the angle control module (2) and the pendulum (4); characterized in that: The control process of the method is as follows: The control of the borderless two-wheeled robot is divided into the control of the starting stage, the forward stage, and the turning stage; The specific process of the starting stage is as follows: Step 1: The angle control module (2) of the borderless two-wheeled robot controls the borderless wheels (3) to be perpendicular or not perpendicular to the ground; Step 2: The motors (3-1) of the two borderless wheels (3) rotate forward simultaneously to generate a backward torque on the central platform (1); Step 3: Under the action of the backward torque generated on the central platform (1), the pendulum (4) is lifted until the auxiliary wheel (4-3) of the pendulum (4) touches the ground; Step 4: After the auxiliary wheel (4-3) touches the ground, the borderless two-wheeled robot starts to move forward. The central platform (1) maintains horizontal under the control of the control circuit, and the auxiliary wheel (4-3) leaves the ground; In step 4, the central platform (1) maintains horizontal under the control of the control circuit; the specific process is as follows: The control circuit first reads the data of the inertial measurement unit installed on the central platform (1) to obtain the pitch angle of the central platform (1); Calculate the deviation value between the measured pitch angle value of the obtained central platform (1) and the expected pitch angle of 0°, and perform PID control based on the deviation value to output the control quantity; Superimpose the PID control output control quantity on the rotational speed of the motors of the borderless wheels (3) themselves to control the central platform (1) to maintain horizontal; When the deviation value is less than ±5°, the central platform (1) is not controlled.

2. The control method of the borderless two-wheeled robot applicable to multiple terrains according to claim 1, wherein: The control process of the forward stage is as follows: The control of the borderless two-wheeled robot in the forward stage is divided into the control of the pendulum (4) and the control of the angle control module (2); A. The control process of the pendulum (4) is as follows: When the borderless two-wheeled robot shows a tendency to tilt to one side; The control circuit first reads the data of the inertial measurement unit installed on the central platform (1) to obtain the roll angle of the central platform (1); Calculate the deviation value between the measured roll angle value of the obtained central platform (1) and the expected roll angle of 0°, and perform PID control based on the deviation value to output the control quantity; Apply the PID control output control quantity to the pendulum (4) to control the speed of the pendulum (4), and complete the roll angle of the central platform (1) of the borderless two-wheeled robot to be horizontal with the ground; When the pendulum (4) swings to the angle limit, the pendulum (4) returns to the central position at a low speed; B. The control process of the angle control module (2) is as follows: The angle control module (2) of the borderless two-wheeled robot controls the borderless wheels (3) to be perpendicular or not perpendicular to the ground according to the terrain; the specific process is as follows: The control circuit first reads the data of the inertial measurement unit installed on the central platform (1) to obtain the roll angle of the central platform (1); Taking the central platform (1) parallel to the ground as 0°; When the roll angle of the central platform (1) is greater than ±15° and the duration is greater than three seconds, the control circuit determines that the current road is a bumpy road and automatically rotates the angle control modules on both sides to lower the center of gravity of the borderless two-wheeled robot body; When the roll angle of the central platform module is less than or equal to ±15° and the duration is greater than three seconds, the control circuit determines that the current road is a flat road and automatically rotates the angle control modules (2) on both sides to complete the control of the angle control module (2) to make the borderless wheels (3) perpendicular to the ground.

3. The control method for a rimless two-wheeled robot applicable to multiple terrains according to claim 2, wherein: The control process during the turning phase is as follows: The control of the borderless two-wheeled robot during the turning phase is divided into the control of the pendulum (4) and the control of the angle control module (2); A. The control process of the pendulum (4) is as follows: When the borderless two-wheeled robot shows a tendency to tilt to one side, the control circuit first reads the data of the inertial measurement unit installed on the central platform (1) to obtain the roll angle of the central platform (1); Calculate the deviation value between the obtained roll angle measurement value and the expected roll angle of 0°, and perform PID control based on the deviation value to output the control quantity; Apply the PID control output control quantity to the pendulum (4) to control the speed of the pendulum (4), and complete the horizontal alignment of the roll angle of the central platform module (1) of the borderless two-wheeled robot with the ground; When the pendulum (4) swings to the angle limit, the pendulum (4) returns to the central position at a low speed; B. The control process of the angle control module (2) is as follows:

1. The motors of the two borderless wheels (3) change their speeds to generate a speed difference to complete the turning; 2. When the borderless two-wheeled robot turns to one side, the control circuit will cause the angle control module (2) on that side to control the inclination of the borderless wheel (3) according to the turning direction to lower the center of gravity of the borderless two-wheeled robot body; When the borderless two-wheeled robot finishes turning, the control circuit will cause the angle control module (2) on that side to control the borderless wheel not to incline, so that the center of gravity of the borderless two-wheeled robot body is restored.

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