Automatic zero setting method for steering wheel of wheeled robot

Abstract

An automatic zeroing method for a steering wheel of a wheeled robot comprises a single-wheel automatic zeroing mode and a complete-machine automatic zeroing mode, single-wheel automatic zeroing operation is carried out firstly, and then complete-machine automatic zeroing operation is carried out; the single-wheel automatic zeroing operation comprises the following steps: controlling a steering engine to be zeroed to rotate clockwise and anticlockwise at a constant speed respectively, and acquiring a first complete machine current value and a second complete machine current value under clockwise and anticlockwise conditions respectively; when it is detected that the first complete machine current value rises to a target threshold value Ia, the current deviation angle theta 1 of the steering engine rotating clockwise is recorded; when it is detected that the second complete machine current value rises to the target threshold value Ia, the current deviation angle theta 2 of the steering engine rotating anticlockwise is recorded; and according to the deviation angle theta1 and the deviation angle theta2, zero deviation information of the wheel is obtained and corrected. Starting from solving the fundamental problems of linear driving, endurance and the like, any external equipment is not needed, and the speed of production manufacturing and field maintenance is greatly increased.

Description

Technical Field

[0001] The invention relates to a wheeled robot, in particular to an automatic zeroing method for a steering wheel of a wheeled robot. Background Art

[0002] In the design and application of modern wheeled robots, the zero position adjustment of the servo is an important technical link to ensure the efficient and stable driving of the robot. Especially in the scenario involving steering control, for wheeled robots with steering servos, the zero position of the servo mainly affects the following aspects: 1) straight-line driving; 2) wear of tires and related structural parts; 3) power consumption and endurance. For example: the zero position deviation of the servo will cause the robot to offset during driving, which is manifested as shaking or deviation when driving in a straight line, reducing the control accuracy; for example: if the servo cannot accurately maintain the zero position, the robot will experience uneven tire wear during driving, which will affect the service life of the tire and increase maintenance costs; and the inaccuracy of the servo zero position will cause the robot to require more power to maintain straight-line driving, which increases energy consumption, thereby affecting the robot's endurance and limiting its working time and efficiency. Therefore, in order to improve the performance and service life of the robot, it is particularly important to adjust the servo to zero.

[0003] At present, tooling is generally used to assist the zeroing of the steering gear. Similar to it, there is a four-wheel alignment instrument for automobiles. For example, CN220649402 U discloses a four-wheel alignment instrument that is easy to operate and can adapt to the detection of automobiles with different wheelbases; CN117491038A discloses a four-wheel alignment instrument to solve the technical problems of the four-wheel alignment instrument in the prior art, such as easy damage to tires, difficulty in adjusting the measurement position, and low accuracy of the measurement results; and CN 117400175A discloses a four-wheel alignment fixture and automatic vehicle moving device for automobiles that are easy to adjust. However, the above patent documents have the following defects: 1) A set of complex equipment is required, which increases the complexity and maintenance difficulty of the zeroing process and increases the cost; 2) It does not directly solve the problems of straight-line driving and endurance.

[0004] In summary, the present invention urgently needs to design an automatic zeroing method for the steering wheel of a wheeled robot to solve the above technical problems. Summary of the invention

[0005] The object of the present invention is to overcome the above-mentioned deficiencies in the prior art and to provide an automatic zeroing method for a steering wheel of a wheeled robot which has the advantages of simple operation, high zeroing accuracy and fast maintenance speed.

[0006] The technical solution of the present invention is: an automatic zeroing method for a steering wheel of a wheeled robot, including a single-wheel automatic zeroing mode and a whole-machine automatic zeroing mode, and the single-wheel automatic zeroing operation is performed first, and then the whole-machine automatic zeroing operation is performed; A. The operation steps of the single-wheel automatic zeroing are: Control the servo to be zeroed to rotate clockwise and counterclockwise at a constant speed, respectively, to obtain a first whole machine current value and a second whole machine current value under clockwise and counterclockwise conditions, respectively; When the first whole machine current value is detected to increase to the target threshold value Ia, the current offset angle θ1 of the clockwise rotating servo is recorded; and when the second whole machine current value is detected to increase to the target threshold value Ia, the current offset angle θ2 of the counterclockwise rotating servo is recorded; Obtain wheel zero position offset information and correct it according to offset angle θ1 and offset angle θ2; B. The operation steps of automatic zeroing of the whole machine are as follows: Control the robot to travel forward a target distance and obtain the forward offset at the target distance; If it is determined that the forward offset does not meet the requirement, the deviation between the robot wheel offset zero position angle and the actual zero position is calculated based on the geometric relationship, and the deviation is corrected; Control the robot to travel backwards the target distance, and obtain a backward offset at the target distance; If it is determined that the backward offset does not meet the requirement, the deviation between the robot wheel offset zero position angle and the actual zero position is calculated based on the geometric relationship, and the deviation is corrected.

[0007] Furthermore, the single-wheel automatic zeroing operation specifically includes the following steps: S1-1: After entering the single-wheel automatic zeroing mode, starting from a certain point, the robot is controlled to move forward at a constant speed, and the servo to be zeroed is controlled to rotate clockwise at a constant speed. When the whole machine current is detected to rise to the target threshold value Ia, the current offset angle θ1 of the servo is recorded; S1-2: Control the servo to be zeroed to rotate counterclockwise at the same speed. When the whole machine current is detected to rise to the target threshold value Ia, the current offset angle θ2 of the servo is recorded. S1-3: Calculate the wheel zero position offset information according to the offset angle θ1 and the offset angle θ2; S1-4: Control the robot to stop moving forward and move back to the starting point, and replace the next wheel to continue the test; after all wheels have completed single-wheel zeroing, perform a set of single-wheel zeroing operations on each wheel according to steps S1-1 to S1-3 until at least two sets of single-wheel zeroing are completed, then stop.

[0008] Furthermore, the steering gear rotates clockwise and counterclockwise at a uniform speed not exceeding 0.3° / s.

[0009] Furthermore, the method for obtaining the target threshold Ia is as follows: before the single-round automatic zeroing operation, the robot is first suspended to measure its no-load current, and the target threshold Ia of the whole machine current is 1.2 to 1.5 times of the no-load current.

[0010] Further, the wheel zero position offset information is obtained by the following formula: wheel zero position offset angle θ0=(θ1+θ2) / 2.

[0011] Furthermore, the automatic zeroing operation of the whole machine specifically includes the following steps: S2-1: After entering the automatic zeroing mode of the whole machine, the robot moves forward with a certain point as the starting point to obtain the displacement data of the robot; S2-2: Determine whether the robot has traveled a distance y. If not, return to step S2-1; if yes, stop moving forward, obtain the displacement data of the robot, and obtain the lateral offset x of the robot; S2-3: Determine whether the lateral offset x of the forward movement meets the requirement. If so, proceed to step S2-5; if not, calculate the deviation between the robot wheel offset zero position angle and the actual zero position according to the geometric relationship; S2-4: Correct the zero position angle of the forward wheel according to the calculated deviation; S2-5: Control the robot to move backward and obtain the displacement data of the robot moving backward; S2-6: During the backward movement, determine whether the robot has traveled a distance y. If not, return to step S2-5; if so, stop moving forward, obtain the robot's displacement data, and obtain the backward lateral offset x1; S2-7: Determine whether the lateral offset x1 of the backward movement meets the requirement. If so, stop zeroing. If not, calculate the deviation between the offset zero position angle of the backward robot wheel and the actual zero position according to the geometric relationship. S2-8: According to the calculated deviation, the wheel offset zero angle in S2-7 is corrected.

[0012] Further, in S2-3, the calculation method of the zero-position angle of the wheel offset of the robot moving forward is: According to the driving distance y and lateral offset x measured by the IMU, the curve is regarded as a part of a full circle to obtain the radius of the full circle as the driving radius r. According to the driving distance y and lateral offset x, the driving radius r is obtained by the following formula: ; The intersection of the perpendicular bisectors of the two front wheels is taken as the center of the circle with a driving radius r. According to the chassis model of the robot, the known conditions are obtained: chassis length L, width D; assuming the zero offset angle of the left front wheel is β, and the zero offset angle of the right front wheel is γ, the zero offset angles of the two front wheels are obtained by the following formula: After calculating β and γ, the β and γ angles are corrected in the opposite direction according to the actual zero position of the wheel.

[0013] Furthermore, in S2-7, the method for calculating the zero-position angle of the wheel offset when the robot is moving backward is the same as the method for calculating the zero-position angle of the wheel offset when the robot is moving forward, and the backward direction is determined by the direction of the robot's rear wheels, and the intersection of the perpendicular bisectors of the two rear wheels is used as the center of the circle of the driving radius r for calculation.

[0014] Further, in S2-7, it is determined whether the forward lateral offset x and the backward lateral offset x1 both meet the requirements. If so, the zero adjustment is stopped; if the forward lateral offset x still does not meet the requirements, the process returns to step S2-1 for the next round of deviation correction until the requirements are met.

[0015] The beneficial effects of the present invention are as follows: on the one hand, starting from solving the fundamental problems of straight-line driving and endurance, single-wheel zeroing and whole-machine zeroing are integrated into the robot, without any external equipment, and multi-wheel positioning can be performed in most places, greatly accelerating the speed of production and manufacturing as well as on-site maintenance; on the other hand, single-wheel zeroing and whole-machine zeroing are two interdependent steps. Only after single-wheel zeroing can whole-machine zeroing be performed. First, single-wheel automatic zeroing is performed according to the current to ensure that the zero position of each wheel is as accurate as possible, thereby reducing the resistance during driving. This means that when driving at a constant speed, the more accurate the zeroing of the wheel, the less current is consumed, which greatly improves energy efficiency; after completing the single-wheel automatic zeroing, the deviation between the wheel zero position and the actual zero position has been significantly reduced, and the subsequent automatic zeroing of the whole machine further optimizes the performance of the overall system, ensures the coordination between the wheels, enhances the stability and accuracy of the system, and ultimately achieves more efficient operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a workflow diagram of single-round automatic zeroing according to an embodiment of the present invention; Figure 2 This is a flowchart of the automatic zeroing of the whole machine according to an embodiment of the present invention; Figure 3 It is a calculation principle diagram of the travel radius r in the automatic zeroing of the whole machine in an embodiment of the present invention; Figure 4 It is a calculation principle diagram of the zero position angle β of the left front wheel in the automatic zeroing of the whole machine in an embodiment of the present invention; Figure 5 It is a calculation principle diagram of the right front wheel offset zero angle γ in the automatic zeroing of the whole machine in the embodiment of the present invention. DETAILED DESCRIPTION

[0017] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0018] Usually, when replacing wheels on a new or old robot, or when the wheels are worn out over time, the wheels need to be zeroed. The present invention includes two steps: single-wheel automatic zeroing and whole-machine automatic zeroing. First, single-wheel automatic zeroing is performed, and then the whole-machine automatic zeroing is performed. The operator can select single-wheel automatic zeroing mode or whole-machine automatic zeroing mode on the terminal or the display screen of the robot, and send a command to enter the corresponding zeroing mode. The specific method is as follows: 1. Single-round automatic zero adjustment based on current: The principle of single-wheel automatic zeroing is: the resistance is minimal after the wheel is accurately zeroed. During the uniform speed driving process, the more accurate the wheel zeroing, the less current is consumed. Figure 1 As shown, the specific steps include: S101: After entering the single-wheel automatic zeroing mode, starting from a certain point, the robot is controlled to move forward at a constant speed, and the servo to be zeroed is controlled to rotate clockwise at a constant speed. When the whole machine current is detected to rise to the target threshold value Ia, the current offset angle θ1 of the servo is recorded; S102: Control the servo to be zeroed to rotate counterclockwise at the same speed, and when it is detected that the whole machine current rises to the target threshold value Ia, record the current offset angle θ2 of the servo; S103: Calculate the wheel zero position offset angle θ0 according to the offset angle θ1 and the offset angle θ2 and correct it; S104: Control the robot to stop moving forward and retreat to the starting point, and replace the next wheel to continue testing; after all wheels have completed single-wheel zeroing, perform a set of single-wheel zeroing operations on each wheel according to steps S101 to S103 until two sets of single-wheel zeroing are completed, then stop.

[0019] In the above-mentioned single-wheel zeroing, the offset angle of the servo refers to the angular offset relative to the zero point of the servo itself when the servo rotates clockwise or counterclockwise to reach the whole machine current threshold.

[0020] In the above steps S101 and S102, the speed of the servo rotating clockwise and counterclockwise uniformly is not greater than 0.3° / s. If it rotates too fast, it will be difficult to identify the trend of current change.

[0021] In addition, the method for obtaining the current target threshold Ia is as follows: before the zeroing operation, the robot is first suspended to measure its no-load current, and the target threshold Ia of the whole machine current is 1.2 to 1.5 times the no-load current, preferably 1.4 times. This embodiment measures the no-load current in the suspended state, and can obtain the true current value of the robot when there is no load, thereby avoiding the interference of the load on the current measurement and ensuring the accuracy of the baseline data; by setting the target threshold to 1.2 to 1.5 times the no-load current, a certain margin can be provided for the robot during operation, thereby effectively preventing overload conditions and avoiding abnormal current increases caused by sudden load increases.

[0022] In the above step S103, the calculation formula of the wheel zero position offset angle θ0 is: θ0=(θ1+θ2) / 2.

[0023] The calculation principle is: when the robot walks in a straight line and the wheels deviate from the zero position, the current consumed will increase, and the more it deviates from the zero position, the greater the current will be. Since the relationship between the angle of the wheel deviation from the zero position and the current is approximately the same in clockwise and counterclockwise rotation, (θ1+θ2) / 2 can be used as the wheel zero position offset angle, which helps to maintain stability during the robot's driving process and avoid tilting or instability caused by deviation. It can be said that this embodiment is simple to calculate, ensures consistency and reliability during the movement of the servo, and enables the entire robot system to operate more smoothly and efficiently.

[0024] In the above step S104, after completing the first single-wheel zeroing, it may be found that the zero position or rotation characteristics of each wheel may be affected by external factors (such as ground friction, wheel wear or uneven load). Therefore, performing another set of zeroing operations can help further improve the accuracy of the robot in motion and ensure that each wheel can accurately reflect its position. This embodiment is a four-wheel robot, so it is necessary to zero the four wheels separately, and each wheel must perform at least two zeroing operations.

[0025] It can be said that the present embodiment utilizes electric current to perform single-wheel automatic zeroing. On the one hand, the current signal can monitor and feedback the status of the wheel in real time, thereby realizing instant adjustment and ensuring that the zeroing process is fast and effective. Moreover, during driving, the current zeroing can be automatically adjusted according to load changes, road conditions and other conditions to maintain the best working state of the wheel with high dynamic adaptability. On the other hand, the difference between the actual position and the target position of the wheel can be accurately judged through the change of current, so as to perform accurate zeroing. Compared with mechanical zeroing, current zeroing can reduce dependence on mechanical components, reduce wear and failure risks, extend equipment life, ensure accurate control of the robot's driving direction and position, and provide a reliable benchmark for subsequent robot navigation and positioning when performing tasks. Moreover, it does not require complex mechanical structures, thus simplifying the design and manufacturing process.

[0026] 2. Automatically adjust the machine to zero according to the deviation: The principle of zeroing the whole machine is: when the robot deviates, the walking curve is a large circle. According to the travel distance and offset recorded by the IMU, the deviation of each wheel from the actual zero position can be obtained through geometric calculation. The zero position can be corrected in the reverse direction with the deviation to achieve zeroing of the whole machine. Figure 2 As shown, the specific steps include: S201: After entering the whole machine automatic zeroing mode, the robot moves forward with a certain point as the starting point to obtain the displacement data of the robot detected by the IMU; S202: Determine whether the robot has traveled a distance y. If not, return to step S201; if yes, stop moving forward, obtain the displacement data of the robot detected by the IMU, and obtain the lateral offset x of the robot; S203: Determine whether the lateral offset x of the forward movement meets the requirement. If so, proceed to step S205; if not, calculate the deviation between the zero position angle of the robot wheel offset and the actual zero position according to the geometric relationship; S204: Correcting the zero-position angle of the wheel according to the calculated deviation; S205: Control the robot to move backward, and obtain the displacement data of the robot detected by the IMU; S206: During the backward movement, determine whether the robot has traveled a distance y. If not, return to step S205; if yes, stop moving forward, obtain the displacement data of the robot detected by the IMU, and obtain the backward lateral offset x1; S207: Determine whether the forward lateral offset x and the backward lateral offset x1 both meet the requirements. If so, stop zeroing; if not, calculate the deviation between the robot wheel zero position offset angle and the actual zero position according to the geometric relationship; S208: Correcting the zero-position angle of the wheel according to the calculated deviation.

[0027] Specifically, in step S202, after the single wheel is automatically zeroed, the robot is controlled to travel long distances in a straight line. Once the robot deviates, the robot's driving trajectory becomes a curve. If the forward lateral offset is not greater than the target offset, there is no need to zero the entire machine. If it is greater than the target offset, it is necessary to calculate the deviation between the robot wheel offset zero angle and the actual zero position based on the geometric relationship.

[0028] The deviation calculation method in step S203 is as follows: First, based on the driving distance y and lateral offset x measured by the IMU, the curve can be regarded as a part of a full circle, so the radius r of the full circle can be obtained, as follows: Figure 3As shown: The robot is approximated to a point, and the driving radius r is obtained by the following formula based on the driving distance y and the lateral offset x: Next, after completing the single-wheel automatic zeroing, the deviation between the zero position of the wheel and the actual zero position is small. At this time, the direction of the robot's front wheels determines the direction of travel, and the influence of the rear wheels can be ignored. Therefore, after determining the driving radius r, since the intersection of the midpoints of the left front wheel and the left rear wheel is the center of the driving radius r, the deviation between the two front wheels and the actual zero position can be calculated based on the robot's chassis model. Figure 4 and Figure 5 As shown: Assume that the left front wheel offset zero angle β, the right front wheel offset zero angle γ, and the chassis length L and width D are known, then: After calculating β and γ, it can be known that the actual zero position of the wheel needs to be corrected in the opposite direction by the β and γ angles respectively.

[0029] Similarly, in steps S206 and S207, the direction of the robot's rear wheels determines the direction of retreat, and the influence of the front wheels can be ignored. Therefore, the calculation of the offset zero angle of the rear wheels is similar to that of the front wheels, and will not be described in detail here. In addition, in step S207, it is also possible to only determine whether the lateral offset x1 of the retreat meets the requirements. When determining whether both the forward lateral offset x and the backward lateral offset x1 meet the requirements, if the forward lateral offset x still does not meet the requirements, it is necessary to continue to return to step S201 for the next round of deviation correction until the requirements are met.

[0030] 3. Hardware configuration.

[0031] The steering wheel is equipped with a steering servo, and the robot is equipped with an IMU for detecting the robot's displacement data and a current sensor for measuring the current of the entire machine. The robot is placed on a non-smooth road with uniform material and can communicate with the terminal, which can be a mobile phone or a computer, and the zero adjustment operation can be controlled by the terminal.

[0032] To sum up, on the one hand, the present invention starts from solving the fundamental problems of straight-line driving and endurance, and integrates single-wheel zeroing and whole-machine zeroing into the robot. No external equipment is required, and multi-wheel positioning can be performed in most places, which greatly speeds up the speed of production and manufacturing as well as on-site maintenance. On the other hand, single-wheel zeroing and whole-machine zeroing are two interdependent steps. Only after single-wheel zeroing can whole-machine zeroing be performed. First, single-wheel automatic zeroing is performed according to the current to ensure that the zero position of each wheel is as accurate as possible, thereby reducing the resistance during driving. This means that when driving at a constant speed, the more accurate the zeroing of the wheel, the less current consumption, which greatly improves energy efficiency. After completing the single-wheel automatic zeroing, the deviation between the wheel zero position and the actual zero position has been significantly reduced. The subsequent automatic zeroing of the whole machine further optimizes the performance of the overall system, ensures the coordination between the wheels, enhances the stability and accuracy of the system, and ultimately achieves more efficient operation.

Claims

1. A method for automatically zeroing a steering wheel of a wheeled robot, characterized in that: It includes single-wheel automatic zeroing mode and whole machine automatic zeroing mode, and the single-wheel automatic zeroing operation is performed first, and then the whole machine automatic zeroing operation is performed; A. The operation steps of the single-wheel automatic zeroing are: Control the servo to be zeroed to rotate clockwise and counterclockwise at a constant speed, respectively, to obtain a first whole machine current value and a second whole machine current value under clockwise and counterclockwise conditions, respectively; When the first whole machine current value is detected to increase to the target threshold value Ia, the current offset angle θ1 of the clockwise rotating servo is recorded; and when the second whole machine current value is detected to increase to the target threshold value Ia, the current offset angle θ2 of the counterclockwise rotating servo is recorded; Obtain wheel zero position offset information and correct it according to offset angle θ1 and offset angle θ2; B. The operation steps of automatic zeroing of the whole machine are as follows: Control the robot to travel forward a target distance and obtain the forward offset at the target distance; If it is determined that the forward offset does not meet the requirement, the deviation between the robot wheel offset zero position angle and the actual zero position is calculated based on the geometric relationship, and the deviation is corrected; Control the robot to travel backwards the target distance, and obtain a backward offset at the target distance; If it is determined that the backward offset does not meet the requirement, the deviation between the robot wheel offset zero position angle and the actual zero position is calculated based on the geometric relationship, and the deviation is corrected.

2. The automatic zeroing method for the steering wheel of a wheeled robot according to claim 1, characterized in that: The single-wheel automatic zeroing operation specifically includes the following steps: S1-1: After entering the single-wheel automatic zeroing mode, starting from a certain point, the robot is controlled to move forward at a constant speed, and the servo to be zeroed is controlled to rotate clockwise at a constant speed. When the whole machine current is detected to rise to the target threshold value Ia, the current offset angle θ1 of the servo is recorded; S1-2: Control the servo to be zeroed to rotate counterclockwise at the same speed. When the whole machine current is detected to rise to the target threshold value Ia, the current offset angle θ2 of the servo is recorded. S1-3: Calculate the wheel zero position offset information according to the offset angle θ1 and the offset angle θ2; S1-4: Control the robot to stop moving forward and move back to the starting point, and replace the next wheel to continue the test; after all wheels have completed single-wheel zeroing, perform a set of single-wheel zeroing operations on each wheel according to steps S1-1 to S1-3 until at least two sets of single-wheel zeroing are completed, then stop.

3. The automatic zeroing method for the steering wheel of a wheeled robot according to claim 1, characterized in that: The steering gear rotates clockwise and counterclockwise at a uniform speed of no more than 0.3° / s.

4. The automatic zeroing method for the steering wheel of a wheeled robot according to claim 1, characterized in that: The method for obtaining the target threshold Ia is as follows: before the single-round automatic zeroing operation, the robot is first suspended to measure its no-load current, and the target threshold Ia of the whole machine current is 1.2 to 1.5 times of the no-load current.

5. The automatic zeroing method for the steering wheel of a wheeled robot according to claim 1, characterized in that: The wheel zero position offset information is obtained by the following formula: wheel zero position offset angle θ0=(θ1+θ2) / 2.

6. The automatic zeroing method for the steering wheel of a wheeled robot according to claim 1, characterized in that: The automatic zeroing operation of the whole machine specifically includes the following steps: S2-1: After entering the automatic zeroing mode of the whole machine, the robot moves forward with a certain point as the starting point to obtain the displacement data of the robot; S2-2: Determine whether the robot has traveled a distance y. If not, return to step S2-1; if yes, stop moving forward, obtain the displacement data of the robot, and obtain the lateral offset x of the robot; S2-3: Determine whether the lateral offset x of the forward movement meets the requirement. If so, proceed to step S2-5; if not, calculate the deviation between the robot wheel offset zero position angle and the actual zero position according to the geometric relationship; S2-4: Correct the zero position angle of the forward wheel according to the calculated deviation; S2-5: Control the robot to move backward and obtain the displacement data of the robot moving backward; S2-6: During the backward movement, determine whether the robot has traveled a distance y. If not, return to step S2-5; if so, stop moving forward, obtain the robot's displacement data, and obtain the backward lateral offset x1; S2-7: Determine whether the lateral offset x1 of the backward movement meets the requirement. If so, stop zeroing. If not, calculate the deviation between the offset zero position angle of the backward robot wheel and the actual zero position according to the geometric relationship. S2-8: According to the calculated deviation, the wheel offset zero angle in S2-7 is corrected.

7. The automatic zeroing method for the steering wheel of a wheeled robot according to claim 6, characterized in that: In S2-3, the calculation method of the zero-position angle of the wheel offset of the robot moving forward is: According to the driving distance y and lateral offset x measured by the IMU, the curve is regarded as a part of a full circle to obtain the radius of the full circle as the driving radius r. According to the driving distance y and lateral offset x, the driving radius r is obtained by the following formula: ； ； The intersection of the perpendicular bisectors of the two front wheels is taken as the center of the circle with a driving radius r. According to the chassis model of the robot, the known conditions are obtained: chassis length L, width D; assuming the zero offset angle of the left front wheel is β, and the zero offset angle of the right front wheel is γ, the zero offset angles of the two front wheels are obtained by the following formula: ; ; After calculating β and γ, the β and γ angles are corrected in the opposite direction according to the actual zero position of the wheel.

8. The automatic zeroing method for the steering wheel of a wheeled robot according to claim 7, characterized in that: In S2-7, the calculation method of the wheel offset zero angle when the robot is moving backward is the same as the calculation method of the wheel offset zero angle when the robot is moving forward, and the backward direction is determined by the direction of the robot's rear wheels, and the intersection of the perpendicular bisectors of the two rear wheels is used as the center of the driving radius r for calculation.

9. The automatic zeroing method for the steering wheel of a wheeled robot according to claim 6, characterized in that: In S2-7, it is determined whether the forward lateral offset x and the backward lateral offset x1 both meet the requirements. If so, the zero adjustment is stopped; if the forward lateral offset x still does not meet the requirements, it continues to return to step S2-1 for the next round of deviation correction until the requirements are met.

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