An AGV chassis steering wheel motion control method, system, medium and product

Abstract

An AGV chassis steering wheel motion control method, system, medium and product, which relates to the field of intelligent control systems G05B. By implementing this application, the control system establishes an AGV vehicle body coordinate system and determines the transitional motion types that the AGV chassis needs to go through when switching from one motion state (initial motion type) to another motion state (final motion type), and based on the preset AGV acceleration and deceleration parameters, it updates the real-time motion speed of the AGV chassis in real time, so that it can determine whether the AGV chassis reaches the final motion type according to the real-time motion speed, achieving precise control of the AGV chassis motion state. When the AGV chassis reaches the final motion type, by calculating the change in the turning radius and the change in the steering angle of each steering wheel, and combining with the AGV chassis layout parameters, the motion direction of each steering wheel is calculated, so as to determine the control result of each steering wheel of the AGV chassis, improving the accuracy and efficiency of the AGV chassis motion control.

Description

Technical Field

[0001] This application relates to the field of intelligent control systems G05B, and particularly to a method, system, medium and product for controlling the movement of the steering wheels of an AGV chassis. Background Art

[0002] In recent years, various forms of AGVs (Automated Guided Vehicles) have been widely used in industrial production, warehousing logistics and other fields. As the core component of an AGV, the flexibility and reliability of the movement control of the AGV chassis directly affect the overall operation efficiency and safety performance of the AGV.

[0003] Currently, the common methods for controlling the movement of an AGV chassis mainly rely on simple switching of movement modes, that is, by setting fixed movement modes, such as linear movement, circular movement, etc., when the AGV needs to change its movement state, the chassis is directly switched to the corresponding movement mode.

[0004] However, in practical applications, when the AGV needs to frequently switch its movement state or work in a complex environment, this simple movement mode switching method will cause the movement of the AGV to be discontinuous, resulting in jitter or oscillation of the AGV during movement. Summary of the Invention

[0005] This application provides a method, system, medium and product for controlling the movement of the steering wheels of an AGV chassis to ensure the stability and safety of the AGV chassis during the process of switching movement states.

[0006] In a first aspect, the present application provides an AGV chassis steering wheel motion control method, which is applied to a control system. The method includes: establishing an AGV vehicle body coordinate system with the center point of the contour of the AGV vehicle body as the origin, where the positive direction of the X-axis of the AGV vehicle body coordinate system is the head direction of the AGV vehicle body, and the positive direction of the Y-axis is the direction obtained by rotating 90 degrees counterclockwise from the positive direction of the X-axis; obtaining the AGV chassis layout parameters and the initial motion speed of the AGV chassis in the AGV vehicle body coordinate system, and determining the initial motion type of the AGV chassis according to the initial motion speed. The AGV chassis layout parameters are used to represent the position coordinates of each steering wheel in the AGV chassis relative to the origin, and the initial motion speed includes the initial motion speed in the X-axis direction, the initial motion speed in the Y-axis direction, and the initial motion angular velocity; calculating the transitional motion type of the AGV vehicle body from the initial motion type to the final motion type, where the transitional motion type is used to represent the temporary motion type of the AGV vehicle body during the motion type switching process, and the initial motion type and the final motion type are different motion types; updating the real-time motion speed of the AGV chassis based on the transitional motion type and the preset AGV acceleration and deceleration parameters, and determining the real-time motion type of the AGV chassis according to the real-time motion speed; when the real-time motion type is the final motion type, calculating the change in turning radius and the change in steering angle of each steering wheel from the initial motion type to the final motion type. The change in turning radius is the path radius change of the turning radius of each steering wheel from the initial motion type to the final motion type, and the change in steering angle is the angular change of the steering angle of each steering wheel from the initial motion type to the final motion type; calculating the motion direction of each steering wheel at a preset moment based on the change in turning radius, the change in steering angle, and the AGV chassis layout parameters.

[0007] By adopting the above technical solutions, first, the control system establishes an AGV vehicle body coordinate system to accurately describe the motion state of the AGV chassis. Next, the control system determines the transitional motion type that the AGV chassis needs to go through when switching from one motion state (initial motion type) to another motion state (final motion type), and updates the real-time motion speed of the AGV chassis in real time based on the preset AGV acceleration and deceleration parameters, so as to be able to determine whether the AGV chassis reaches the final motion type according to the real-time motion speed, realizing precise control of the motion state of the AGV chassis. When the AGV chassis reaches the final motion type, by calculating the change in turning radius and the change in steering angle of each steering wheel, and combining the AGV chassis layout parameters, the motion direction of each steering wheel is calculated, thereby determining the control result of each steering wheel of the AGV chassis. This control method can not only ensure the stability and safety of the AGV chassis during the motion state switching process, but also adapt to various complex motion scenarios, improving the accuracy and efficiency of the AGV chassis motion control.

[0008] In combination with some embodiments of the first aspect, in some embodiments, before the step of calculating the transitional motion type of the AGV vehicle body from the initial motion type to the final motion type, the method further includes: if the AGV vehicle body makes a lateral movement from the initial motion type to the final motion type, calculating the minimum turning radius allowed for the AGV vehicle body according to the AGV chassis layout parameters; judging whether it is necessary to limit the motion angular velocity according to the minimum turning radius; if it is necessary to limit the motion angular velocity, calculating the speed-limiting motion angular velocity so that the motion angular velocity of the AGV vehicle body does not exceed the speed-limiting motion angular velocity during the motion type switching process.

[0009] By adopting the above technical solution, the control system judges whether the AGV chassis needs to make a lateral movement. If a lateral movement is required, the minimum turning radius allowed is calculated according to the AGV chassis layout parameters, and based on this, it is judged whether it is necessary to limit the motion angular velocity. When it is necessary to limit the motion angular velocity, the control system calculates the speed-limiting motion angular velocity to ensure that the motion angular velocity of the AGV during the motion state switching process does not exceed the speed-limiting motion angular velocity (the motion angular velocity safety threshold). This pre-constraint mechanism avoids the instability problem caused by excessive motion angular velocity during the lateral movement of the AGV chassis, and improves the safety and reliability of motion control.

[0010] In combination with some embodiments of the first aspect, in some embodiments, after the step of if it is necessary to limit the motion angular velocity, calculating the speed-limiting motion angular velocity so that the motion angular velocity of the AGV vehicle body does not exceed the speed-limiting motion angular velocity during the motion type switching process, the method further includes: calculating the position of the rotation point of the motion trajectory in the AGV vehicle body coordinate system according to the final motion type and the input final motion speed in the X-axis direction, the final motion speed in the Y-axis direction, and the speed-limiting motion angular velocity; calculating the respective final steering angles corresponding to each steering wheel based on the position of the rotation point.

[0011] By adopting the above technical solution, the control system calculates the position of the rotation point of the AGV chassis motion trajectory according to the final motion type, the target motion speed, and the speed-limiting motion angular velocity, and based on this, calculates in advance the respective final steering angles required for each steering wheel. When it is judged in the next step whether each steering wheel stops rotating and whether the current steering angle corresponding to each steering wheel is consistent with the respective final steering angle corresponding to each steering wheel, it provides a clear comparison target for the control system.

[0012] In some embodiments in combination with some embodiments of the first aspect, after the step of calculating the transitional motion type of the AGV vehicle body from the initial motion type to the final motion type, the method further includes: when the AGV vehicle body changes from the initial motion type to the transitional motion type, determining whether each steering wheel stops rotating and whether the current steering angle corresponding to each steering wheel is consistent with the final steering angle corresponding to each steering wheel; if so, switching the motion state of the AGV vehicle body to the execution state, and controlling each steering wheel to perform corresponding motions according to the final motion type and the speed-limited motion angular velocity; if not, keeping the motion state of the AGV vehicle body as the initialization state, controlling the AGV vehicle body to execute a parking instruction, and driving each steering wheel to rotate to the angular position corresponding to the final steering angle respectively.

[0013] By adopting the above technical solution, when the AGV chassis switches from the initial motion type to the transitional motion type, the control system determines whether each steering wheel stops rotating and whether the current steering angle corresponding to each steering wheel is consistent with the final steering angle corresponding to each steering wheel, so as to realize the safe switching of the motion state. When the conditions are met, the control system switches the AGV chassis to the execution state and controls the motion of the steering wheels according to the final motion type and the speed-limited angular velocity; when the conditions are not met, the control system keeps the initialization state and executes the parking instruction. This method effectively avoids the impact and instability during the motion state switching of the AGV chassis, and improves the safety and reliability of the AGV chassis during the motion process.

[0014] In some embodiments in combination with some embodiments of the first aspect, the real-time motion types include parking, forward, backward, left shift, right shift, left front diagonal movement, right front diagonal movement, left rear diagonal movement, right rear diagonal movement, counterclockwise rotation in place, and clockwise rotation in place.

[0015] By adopting the above technical solution, the control system defines a variety of real-time motion types including parking, forward, backward, left shift, right shift, left front diagonal movement, right front diagonal movement, left rear diagonal movement, right rear diagonal movement, counterclockwise rotation in place, and clockwise rotation in place, realizing the complete coverage of the all-round motion ability of the AGV chassis, enabling the AGV to cope with various complex motion scenarios, and significantly improving the mobility and flexibility of the AGV chassis.

[0016] In some embodiments in combination with some embodiments of the first aspect, based on the turning radius change amount, the steering angle change amount, and the AGV chassis layout parameters, calculate the motion direction of each steering wheel at a preset moment, specifically including: calculating the predicted position coordinates of the AGV chassis at the preset moment according to the real-time motion speed of the AGV chassis; determining the first predicted positions reached by each steering wheel at the preset moment in the forward rotation case and the second predicted positions reached by each steering wheel at the preset moment in the reverse rotation case based on the turning radius change amount, the steering angle change amount, and the AGV chassis layout parameters; determining the rotation direction of each steering wheel according to the distances from the first predicted position and the second predicted position to the predicted position coordinates respectively.

[0017] By adopting the above technical solution, the predicted position coordinates of the AGV chassis at a preset moment are calculated, and combined with the change amount of the turning radius, the change amount of the rudder angle, and the chassis layout parameters, the predicted positions of each steering wheel in the forward and reverse cases are calculated respectively, so as to determine the rotation direction of each steering wheel, improving the accuracy of the steering wheel motion control.

[0018] Combined with some embodiments of the first aspect, in some embodiments, according to the distances from the first predicted position and the second predicted position to the predicted position coordinates respectively, the rotation direction of each steering wheel is determined, specifically including: determining a first distance according to the first predicted position and the predicted position coordinates, and determining a second distance according to the second predicted position and the predicted position coordinates; when the first distance is less than or equal to the second distance, it is determined as forward rotation; when the first distance is greater than the second distance, it is determined as reverse rotation.

[0019] By adopting the above technical solution, the control system determines the first predicted position of each steering wheel at a preset moment in the forward rotation case and the second predicted position of each steering wheel at a preset moment in the reverse rotation case, and compares the first predicted position and the second predicted position with the predicted position coordinates respectively, so as to determine whether each steering wheel is rotating forward or backward, realizing the accuracy of the control of each steering wheel.

[0020] In a second aspect, an embodiment of the present application provides a control system, which includes: one or more processors and a memory; the memory is coupled to the one or more processors, and the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to enable the control system to execute the method described in the first aspect and any possible implementation manner in the first aspect.

[0021] In a third aspect, an embodiment of the present application provides a computer program product containing instructions, when the above computer program product runs on a control system, enabling the above control system to execute the method described in the first aspect and any possible implementation manner in the first aspect.

[0022] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, including instructions, when the above instructions run on a control system, enabling the above control system to execute the method described in the first aspect and any possible implementation manner in the first aspect.

[0023] It can be understood that the control system provided in the second aspect above, the computer program product provided in the third aspect, and the computer storage medium provided in the fourth aspect are all used to execute the method provided in the embodiments of the present application. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding method, and will not be elaborated here.

[0024] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0025] 1. By adopting the above technical solution, first, the control system establishes the AGV vehicle body coordinate system to accurately describe the motion state of the AGV chassis. Then, the control system determines the transitional motion type that the AGV chassis needs to experience when switching from one motion state (initial motion type) to another motion state (final motion type), and based on the preset AGV acceleration and deceleration parameters, it updates the real-time motion speed of the AGV chassis in real time. Thus, it can determine whether the AGV chassis reaches the final motion type according to the real-time motion speed, achieving precise control of the motion state of the AGV chassis. When the AGV chassis reaches the final motion type, by calculating the change amount of the turning radius and the change amount of the steering angle of each steering wheel, and combining with the AGV chassis layout parameters, the motion direction of each steering wheel is calculated, thereby determining the control result of each steering wheel of the AGV chassis. This control method can not only ensure the stability and safety of the AGV chassis during the motion state switching process, but also adapt to various complex motion scenarios, improving the accuracy and efficiency of the motion control of the AGV chassis.

[0026] 2. By adopting the above technical solution, when the AGV chassis switches from the initial motion type to the transitional motion type, the control system determines whether each steering wheel stops rotating and whether the current steering angle corresponding to each steering wheel is consistent with the final steering angle corresponding to each steering wheel, so as to achieve a safe switch of the motion state. When the conditions are met, the control system switches the AGV chassis to the execution state and controls the motion of the steering wheels according to the final motion type and the speed-limiting angular velocity; when the conditions are not met, the control system maintains the initialization state and executes the parking instruction. This method effectively avoids the impact and instability during the motion state switching process of the AGV chassis, improving the safety and reliability of the AGV chassis during the motion process.

[0027] 3. By adopting the above technical solution, the predicted position coordinates of the AGV chassis at a preset moment are calculated, and combined with the change amount of the turning radius, the change amount of the steering angle, and the chassis layout parameters, the predicted positions of each steering wheel in the forward and reverse rotation cases are calculated respectively, thereby determining the rotation direction of each steering wheel, improving the accuracy of the steering wheel motion control. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a flowchart of a method for controlling the motion of the steering wheels of the AGV chassis in the embodiments of the present application;

[0029] Figure 2 is another flowchart of a method for controlling the motion of the steering wheels of the AGV chassis in the embodiments of the present application;

[0030] Figure 3 is a schematic structural diagram of an entity device of the control system in the embodiments of the present application. Detailed implementation manners

[0031] The terms used in the following embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. As used in the specification of the present application, the singular forms "a", "an", "the above", "the", and "this" are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used in the present application refers to any or all possible combinations including one or more of the listed items.

[0032] Hereinafter, the terms "first" and "second" are only used for descriptive purposes, and cannot be construed as implying or suggesting relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present application, unless otherwise specified, the meaning of "a plurality" is two or more.

[0033] The following describes the process of the method provided in this embodiment. Please refer to Figure 1 , which is a schematic flowchart of the AGV chassis steering wheel motion control method in the embodiments of the present application.

[0034] S101. Taking the center point of the contour of the AGV vehicle body as the origin, establish an AGV vehicle body coordinate system. The AGV vehicle body coordinate system takes the head direction of the AGV vehicle body as the positive direction of the X-axis, and the direction obtained by rotating 90 degrees counterclockwise from the positive direction of the X-axis as the positive direction of the Y-axis;

[0035] Among them, the AGV vehicle body refers to an automatic guided transport vehicle, and the contour of the AGV vehicle body refers to the closed figure formed by the outermost edge of the AGV chassis. The center point of the contour represents the geometric center of the closed figure. The AGV vehicle body coordinate system is a two-dimensional plane rectangular coordinate system used to describe the positions of points on the AGV vehicle body. The positive direction of the X-axis represents the advancing direction of the AGV vehicle body, and the positive direction of the Y-axis represents the direction obtained by rotating 90 degrees counterclockwise from the positive direction of the X-axis.

[0036] Specifically, the control system needs to establish a reference coordinate system for describing the motion state of the AGV vehicle body, that is, the AGV vehicle body coordinate system. Taking the center point of the contour of the AGV vehicle body as the origin and the AGV head orientation as the positive direction of the X-axis, an AGV vehicle body coordinate system that conforms to the right-hand coordinate system rule is established, so that the position and motion state of any point on the AGV vehicle body can be accurately described.

[0037] Taking the center point of the contour of the AGV vehicle body as the origin, the head direction of the AGV vehicle body as the positive direction of the X-axis, the direction obtained by rotating 90 degrees counterclockwise from the positive direction of the X-axis as the positive direction of the Y-axis, and the angular measure is positive in the counterclockwise direction. The variables of the AGV chassis are described as follows in the table:

[0038] Table 1 AGV Chassis Variable Table

[0039]

[0040] S102. Obtain the AGV chassis layout parameters and the initial motion speed of the AGV chassis in the AGV vehicle coordinate system, and determine the initial motion type of the AGV chassis according to the initial motion speed. The AGV chassis layout parameters are used to represent the position coordinates of each steering wheel in the AGV chassis relative to the origin. The initial motion speed includes the initial motion speed in the X-axis direction, the initial motion speed in the Y-axis direction, and the initial angular velocity of motion.

[0041] Among them, the AGV chassis layout parameters refer to the set of parameters describing the distribution positions of each steering wheel on the AGV chassis, including the X and Y coordinate values of each steering wheel relative to the origin. The initial motion speed is used to represent the current motion state of the AGV chassis, including the linear velocity in the X-axis direction and the Y-axis direction and the angular velocity around the Z-axis. The initial motion type refers to the current motion mode of the AGV, such as forward, backward, lateral movement, etc.

[0042] Specifically, assuming there is a four-wheel AGV chassis, then the AGV chassis layout parameters (relative to the center point of the vehicle body ) are as follows:

[0043] Left front wheel: (0.4m, 0.3m);

[0044] Right front wheel: (0.4m, -0.3m);

[0045] Left rear wheel: (-0.4m, 0.3m);

[0046] Right rear wheel: (-0.4m, -0.3m).

[0047] Examples of initial motion speed:

[0048] Case 1: Forward:

[0049] Initial motion speed in the X-axis direction: 1.0m / s (forward);

[0050] Initial motion speed in the Y-axis direction: 0m / s;

[0051] Initial angular velocity of motion: 0rad / s;

[0052] Initial motion type: Forward.

[0053] Case 2: Diagonal movement:

[0054] Initial motion speed in the X-axis direction: 0.7m / s (forward);

[0055] Initial motion speed in the Y-axis direction: 0.5m / s (left);

[0056] Initial moving angular velocity: 0 rad / s;

[0057] Initial moving type: Diagonal movement.

[0058] Case 3: Rotating in place:

[0059] Initial moving velocity in the X-axis direction: 0 m / s;

[0060] Initial moving velocity in the Y-axis direction: 0 m / s;

[0061] Initial moving angular velocity: 0.5 rad / s (clockwise);

[0062] Initial moving type: Rotation.

[0063] Other examples of initial moving velocities are not listed here one by one.

[0064] Based on the initial moving velocity in the X-axis direction, the initial moving velocity in the Y-axis direction, and the initial moving angular velocity, the control system can determine the current moving state of the AGV chassis and determine the initial moving type of the AGV chassis.

[0065] S103. Calculate the transitional moving type of the AGV vehicle body from the initial moving type to the final moving type. The transitional moving type is used to represent the temporary moving type of the AGV vehicle body during the moving type switching process. The initial moving type and the final moving type are different moving types;

[0066] Among them, the transitional moving type refers to the temporary moving state of the AGV chassis during the process of switching from the initial moving state to the final moving state. The final moving type refers to the final moving state that the AGV chassis needs to reach.

[0067] Specifically, when the AGV chassis needs to switch from one moving state to another, the control system will determine the transitional moving type, ensuring the stability and safety during the switching process. The control system will select the optimal transitional moving type according to the characteristics of the initial moving type and the final moving type, combined with the kinematic constraints of the AGV.

[0068] The following lists a specific example to illustrate the transitional process of the AGV chassis from the initial moving type to the final moving type:

[0069] Switching from forward movement to leftward movement:

[0070] Initial moving type: Forward movement along the positive X-axis;

[0071] Final moving type: Leftward movement along the positive Y-axis;

[0072] Transition motion type: First, decelerate the forward motion until it stops, and then gradually adjust the steering wheel angle to enter the leftward movement state;

[0073] Description of the transition process: The AGV needs to first decelerate while maintaining the forward direction. After the speed drops to a safe value, each steering wheel starts to synchronously adjust the steering angle and gradually transitions to the leftward movement state.

[0074] S104. Based on the transition motion type and the preset AGV acceleration and deceleration parameters, update the real-time motion speed of the AGV chassis, and determine the real-time motion type of the AGV chassis according to the real-time motion speed;

[0075] Among them, the preset AGV acceleration and deceleration parameters refer to the preset acceleration and deceleration limit values of the AGV chassis, which are used to control the speed change rate of the AGV chassis during the movement process. The real-time motion speed refers to the speed state of the AGV chassis at the current moment, including the linear velocities in the X-axis and Y-axis directions and the angular velocity around the Z-axis. The real-time motion type refers to the motion mode of the AGV chassis determined according to the speed state at the current moment.

[0076] Specifically, the control system calculates the real-time motion speed of the AGV chassis from the initial motion type to the transition motion type and then to the final motion type based on the determined transition motion type and in combination with the preset AGV acceleration and deceleration parameters.

[0077] Taking the transition of the AGV chassis from forward to left lateral movement as an example:

[0078] The preset AGV acceleration and deceleration parameters are: maximum acceleration: 0.5 m / s²; maximum deceleration: -0.5 m / s²; maximum linear velocity: 1.0 m / s;

[0079] Calculation of the speed in three stages:

[0080] (1) The first stage (initial forward):

[0081] In the X direction: uniformly accelerate from 0 to 1.0 m / s;

[0082] In the Y direction: remain 0;

[0083] Angular velocity: remain 0;

[0084] (2) The second stage (transition stage):

[0085] In the X direction: uniformly decelerate from 1.0 m / s to 0;

[0086] In the Y direction: remain 0;

[0087] Angular velocity: remain 0;

[0088] (3) The third stage (stable lateral movement):

[0089] X - direction: Keep at 0;

[0090] Y - direction: Uniformly accelerate from 0 to 1.0 m / s;

[0091] Angular velocity: Keep at 0.

[0092] The method for determining the real - time motion type of the AGV chassis according to the real - time motion speed can refer to the method for determining the initial motion type of the AGV chassis according to the initial motion speed. Different motion speeds correspond to different motion types, which are not limited here. By judging the real - time motion type of the AGV chassis, it can provide a basis for subsequent control decisions.

[0093] It should be noted that the AGV chassis steering wheel motion control method in this application supports the switching and control of multiple motion types, including parking, forward, backward, left shift, right shift, left - front diagonal movement, right - front diagonal movement, left - rear diagonal movement, right - rear diagonal movement, counter - clockwise in - place rotation, and clockwise in - place rotation, and can achieve a smooth transition between any two motion types.

[0094] S105. When the real - time motion type is the final motion type, calculate the change amount of the turning radius and the change amount of the steering angle of each steering wheel from the initial motion type to the final motion type. The change amount of the turning radius is the path radius change amount of the turning radius of each steering wheel changing from the turning radius of the initial motion type to the turning radius of the final motion type, and the change amount of the steering angle is the angle change amount of the steering angle of each steering wheel rotating from the steering angle of the initial motion type to the steering angle of the final motion type;

[0095] Among them, the change amount of the turning radius is used to describe the change degree of the curvature of the steering wheel motion trajectory, indicating the change value of the turning radius during the process of the steering wheel from the initial motion state to the final motion state. The change amount of the steering angle represents the change value of the steering angle of the steering wheel, and is used to describe the rotation angle required for the steering wheel direction to be adjusted from the initial motion state to the final motion state.

[0096] Specifically, when the AGV chassis reaches the final motion type, the control system needs to calculate the change amount of the turning radius and the change amount of the steering angle of each steering wheel from the initial motion state to the final motion state. The change amount of the turning radius determines the shape change of the steering wheel motion trajectory, and the change amount of the steering angle determines the direction angle that the steering wheel needs to adjust. These calculation results provide a necessary parameter basis for realizing precise steering wheel control.

[0097] According to the real - time motion speed of the AGV chassis, the real - time turning radius of the AGV chassis can be calculated (taking forward motion as an example) . At this time, the position of the rotation point of the running trajectory in the AGV vehicle body coordinate system is , and the steering angle of each steering wheel can be calculated , the turning radius of each steering wheel The traveling speed of each steering wheel After being processed by the angle constraint function, the output steering angles of each steering wheel can be obtained . It should be noted that the meanings of each variable name can be seen in the table in step S101 and will not be elaborated here

[0098] According to the output steering angles and turning radii of each steering wheel calculated under the final motion type, and the output steering angles and turning radii of each steering wheel calculated under the initial motion type, the change amount of the turning radius and the change amount of the steering angle of each steering wheel from the initial motion type to the final motion type can be determined

[0099] Suppose the AGV changes from moving left in a straight line to moving forward in a left turn:

[0100] Taking the right front wheel as an example:

[0101] Initial motion type (moving left in a straight line):

[0102] Initial steering angle: 90 degrees (positive);

[0103] Initial turning radius: infinity (straight line);

[0104] Final motion type (moving forward in a left turn):

[0105] Final steering angle: 15 degrees;

[0106] Final turning radius: 2 meters;

[0107] Therefore, the change amount of the steering angle of this right front wheel: 75 degrees; the change amount of the turning radius: from ∞ to 2 meters

[0108] S106. Based on the change amount of the turning radius, the change amount of the steering angle, and the AGV chassis layout parameters, calculate the motion direction of each steering wheel at a preset moment

[0109] Among them, the preset moment refers to a future time point preset by the control system, assumed to be t. The motion direction refers to the traveling direction of each steering wheel at the preset moment, including two situations: forward rotation and reverse rotation

[0110] Specifically, according to the real-time motion speed of the AGV chassis, calculate the position coordinates of the AGV chassis after t seconds (taking forward motion as an example) , , .

[0111] According to the steering angles of each steering wheel , the running speed , and the position parameters , calculate the position parameters of the steering wheel after t seconds , Calculate the positions of the steering wheels after rotating forward for t seconds and then backward for t seconds respectively, with the current steering angle and running speed of the steering wheels. , , , . If , it indicates that the steering wheel needs to rotate forward , and vice versa, it needs to rotate backward. .

[0112] Optionally, generally, based on the change in turning radius, the change in steering angle, and the AGV chassis layout parameters, calculating the movement directions of each steering wheel at a preset moment can be achieved in the following way, which is not limited here: According to the real-time movement speed of the AGV chassis, calculate the predicted position coordinates of the AGV chassis at the preset moment; Based on the change in turning radius, the change in steering angle, and the AGV chassis layout parameters, determine the first predicted positions that each steering wheel reaches in the forward rotation case and the second predicted positions that each steering wheel reaches in the reverse rotation case at the preset moment; According to the distances from the first predicted positions and the second predicted positions to the predicted position coordinates respectively, determine the rotation directions of each steering wheel.

[0113] Optionally, generally, according to the distances from the first predicted positions and the second predicted positions to the predicted position coordinates respectively, determining the rotation directions of each steering wheel can be achieved in the following way, which is not limited here: Determine the first distance according to the first predicted position and the predicted position coordinates, and determine the second distance according to the second predicted position and the predicted position coordinates; When the first distance is less than or equal to the second distance, determine it as forward rotation; When the first distance is greater than the second distance, determine it as reverse rotation.

[0114] The first step: Calculate the predicted position coordinates of the AGV chassis:

[0115] Input parameters: The real-time movement speed of the AGV chassis (including linear speed and angular speed);

[0116] Calculation method: Use the kinematic equation to project the real-time movement speed after the preset moment;

[0117] Output result: The predicted position coordinates (x_pred, y_pred) of the AGV chassis at the preset moment;

[0118] Example: If the current speed of the AGV chassis is 1 m / s and the predicted moment is the 0.5th second, it can be predicted that it will move forward 0.5 meters in a straight-line motion case.

[0119] The second step: Calculate two possible predicted positions of the steering wheel:

[0120] Calculate the forward rotation situation (the first predicted position): Considering the change in turning radius and the change in rudder angle, and combining with the AGV chassis layout parameters (the position of each steering wheel relative to the center point of the vehicle body), obtain the predicted position (x1_i, y1_i) of each steering wheel in the forward rotation situation;

[0121] Calculate the reverse rotation situation (the second predicted position): Using the same parameters, considering the situation of the reverse rotation of the steering wheel, obtain the predicted position (x2_i, y2_i) of each steering wheel in the reverse rotation situation.

[0122] The third step: Determine the optimal operation direction:

[0123] For each steering wheel i, calculate two distances:

[0124] d1_i = The distance from the first predicted position to the predicted position coordinates;

[0125] d2_i = The distance from the second predicted position to the predicted position coordinates;

[0126] Compare the distances:

[0127] If d1_i < d2_i, select the forward rotation direction;

[0128] If d1_i > d2_i, select the reverse rotation direction;

[0129] If d1_i = d2_i, the direction can be selected according to other factors (such as the current motion state).

[0130] Specific calculation example:

[0131] Suppose the parameters of a certain steering wheel are as follows:

[0132] The current position parameters: (0.5, 0.3) meters;

[0133] The predicted position coordinates of the AGV chassis: (1.0, 0.5) meters;

[0134] The first predicted position: (0.8, 0.6) meters;

[0135] The second predicted position: (0.7, 0.2) meters;

[0136] Calculate the distances:

[0137] d1 = √((0.8 - 1.0)² + (0.6 - 0.5)²) = 0.22 meters;

[0138] d2 = √((0.7 - 1.0)² + (0.2 - 0.5)²) = 0.42 meters;

[0139] Since d1 < d2, the forward rotation direction is selected as the movement direction of the steering wheel. This method can ensure that the steering wheel selects the optimal movement path, reduce unnecessary adjustment time, and improve the movement efficiency of the AGV.

[0140] By adopting the above technical solution, first, the control system establishes an AGV vehicle body coordinate system to accurately describe the movement state of the AGV chassis. Then, the control system determines the transitional movement type that the AGV chassis needs to go through when switching from one movement state (initial movement type) to another movement state (final movement type), and updates the real-time movement speed of the AGV chassis in real time based on the preset AGV acceleration and deceleration parameters, so as to be able to determine whether the AGV chassis reaches the final movement type according to the real-time movement speed, realizing precise control of the movement state of the AGV chassis. When the AGV chassis reaches the final movement type, by calculating the change amount of the turning radius and the change amount of the steering angle of each steering wheel, and combining with the AGV chassis layout parameters, the movement direction of each steering wheel is calculated, so as to determine the control result of each steering wheel of the AGV chassis. This control method can not only ensure the stability and safety of the AGV chassis during the movement state switching process, but also adapt to various complex movement scenarios, improving the accuracy and efficiency of the movement control of the AGV chassis.

[0141] The following further describes the more specific process of the method provided in this embodiment. Please refer to Figure 2 , which is another process schematic diagram of the AGV chassis steering wheel movement control method in the embodiment of the present application.

[0142] Before step S104, the following steps may also be executed, or may not be executed, and this is not limited herein:

[0143] S201. If the AGV vehicle body makes a lateral movement from the initial movement type to the final movement type, calculate the minimum turning radius allowed for the AGV vehicle body according to the AGV chassis layout parameters.

[0144] Among them, the lateral movement refers to the translational movement of the AGV vehicle body along the direction perpendicular to the head of the AGV vehicle body while keeping the orientation of the AGV head unchanged. The AGV chassis layout parameters are used to represent the position coordinates and installation angles of each steering wheel relative to the center point of the contour of the AGV vehicle body. The minimum turning radius is used to represent the radius value of the minimum turning arc allowed for the AGV vehicle body during movement, and this radius value is limited by the physical structure of the AGV chassis and the maximum steering angle of each steering wheel.

[0145] Specifically, when the control system detects that the AGV vehicle body needs to perform a lateral movement when switching from the initial motion type to the final motion type, safety verification is required. The control system analyzes the AGV chassis layout parameters, including the spatial distribution positions of each steering wheel, the maximum steering angle, etc., and calculates the theoretically allowable minimum turning radius of the AGV vehicle body when performing a lateral movement. This calculation process needs to consider the geometric constraints of the AGV chassis to ensure that all steering wheels can achieve the expected steering angle within their mechanical limits. For example, normally, the steering wheel can generally only rotate about ±130 degrees. When performing a lateral movement, it is necessary to limit the turning radius of the AGV vehicle body to avoid the steering angle of the steering wheel exceeding the allowable rotation range. When performing a lateral movement, the minimum turning radius allowed for the AGV vehicle body , if it indicates that the movement angular velocity is too large, resulting in too small a turning radius, and the movement angular velocity needs to be restricted , thereby restricting the turning radius of the entire vehicle.

[0146] S202. Determine whether it is necessary to restrict the movement angular velocity according to the minimum turning radius.

[0147] Among them, the minimum turning radius refers to the minimum turning arc radius that the AGV vehicle body can achieve during the movement process, and it is a limiting parameter related to the physical structure of the AGV chassis. The movement angular velocity refers to the speed at which the AGV vehicle body rotates around its vertical axis, expressed in radians per second (rad / s). Restricting the movement angular velocity refers to the limiting value that restricts the movement angular velocity of the AGV vehicle body to ensure movement safety.

[0148] Specifically, the control system calculates the minimum turning radius based on step S201 and determines whether it is necessary to restrict the movement angular velocity. The judgment process can use the following formula: ω_max = v / R_min, where ω_max is the maximum allowable angular velocity, v is the linear velocity of the AGV chassis, and R_min is the minimum turning radius. If the currently planned movement angular velocity is greater than ω_max, then restriction is required; if the currently planned movement angular velocity is less than or equal to ω_max, then no restriction is required. For example, when the AGV chassis moves at a linear velocity of 1.5 m / s and the minimum turning radius is 2 meters, the maximum allowable angular velocity is 0.75 rad / s. If the planned movement angular velocity exceeds this value, restriction is required.

[0149] S203. If it is necessary to restrict the movement angular velocity, calculate the speed-limited movement angular velocity so that the movement angular velocity of the AGV vehicle body does not exceed the speed-limited movement angular velocity during the movement type switching process.

[0150] Among them, the speed-limited movement angular velocity refers to the maximum allowable angular velocity of the AGV vehicle body on the premise of ensuring safe movement.

[0151] Specifically, when the control system determines that the angular velocity of motion needs to be restricted, it calculates the speed-limited angular velocity of motion. The calculation process needs to consider multiple factors: First, based on the minimum turning radius and the current linear velocity, calculate the theoretical maximum angular velocity ω_max = v / R_min; Second, consider the characteristics of the power system of the AGV chassis to determine the angular acceleration limit α_max; Finally, combine the actual motion state of the AGV chassis to determine a speed-limited angular velocity ω_limit that satisfies all constraints. This speed-limiting value needs to satisfy: ω_limit ≤ ω_max, and the rate of change does not exceed α_max. For example, if the theoretical maximum angular velocity is 0.75 rad / s, considering the characteristics of the power system, the final speed-limited angular velocity of motion may be set to 0.6 rad / s, leaving enough safety margin to ensure the smoothness and safety of the AGV chassis during the motion type switching process.

[0152] S204. Calculate the position of the rotation point of the motion trajectory in the AGV body coordinate system according to the final motion type and the final motion velocity in the X-axis direction, the final motion velocity in the Y-axis direction, and the speed-limited angular velocity of motion input.

[0153] Among them, the final motion type refers to the target motion type that the AGV body needs to achieve. The final motion velocity in the X-axis direction and the final motion velocity in the Y-axis direction are pre-input by the user to represent the target velocity components in the X-axis direction and the Y-axis direction of the AGV chassis in the AGV body coordinate system. The position of the rotation point of the motion trajectory refers to the coordinate position of the instantaneous rotation center of the AGV chassis motion trajectory in the AGV body coordinate system, and this coordinate position is an important reference point for calculating the steering angle of the steering wheels.

[0154] Specifically, the control system calculates the position of the rotation point of the AGV chassis motion trajectory according to the given final motion type and the final motion velocity in the X-axis direction, the final motion velocity in the Y-axis direction, and the speed-limited angular velocity of motion input. For different final motion types, the calculation methods are different: (1) Linear motion, the rotation point position is at infinity; (2) Pure rotation motion, the rotation point position is at the center point of the contour of the AGV body; (3) Composite motion, the rotation point position can be calculated by the principle of velocity synthesis. The calculation formula is: when the angular velocity of motion is not zero, the rotation point coordinates Os(x, y) satisfy x = -Vy / Ω, y = Vx / Ω, where Vx and Vy are the final motion velocities in the X-axis direction and the Y-axis direction respectively. For example, when the AGV body moves forward at a linear velocity of 1 m / s and rotates counterclockwise at an angular velocity of 0.5 rad / s, the rotation point position is (0, 2) meters.

[0155] S205. Calculate the final steering angles corresponding to each steering wheel based on the position of the rotation point.

[0156] Among them, the steering wheel refers to the wheel assembly in the AGV vehicle body that can actively adjust the steering angle. The final steering angle is used to represent the target steering angle that each steering wheel needs to reach.

[0157] Specifically, the control system calculates the corresponding final steering angle for each steering wheel based on the rotation point position obtained in step S204 and in combination with the AGV chassis layout parameters. The calculation process is as follows: First, determine the position vector of each steering wheel relative to the rotation point; then, calculate the tangential movement direction of the steering wheel according to the position vector of the steering wheel and the desired movement direction; finally, convert the tangential movement direction into a steering angle value. The formula for calculating the steering angle value is: θi = arctan((yi - Osy) / (xi - Osx)) + π / 2, where (xi, yi) is the position coordinate of the i-th steering wheel, and (Osx, Osy) is the rotation point position. For example, for the steering wheel located at the front right of the AGV vehicle body, if the rotation point position is (0, 2) meters and the position coordinate of the steering wheel is (0.8, 0.6) meters, then its final steering angle is approximately 1.17 radians (67 degrees).

[0158] S206. Calculate the transitional movement type of the AGV vehicle body from the initial movement type to the final movement type. The transitional movement type is used to represent the temporary movement type of the AGV vehicle body during the movement type switching process. The initial movement type and the final movement type are different movement types.

[0159] Specifically, reference can be made to step S103, which is not limited herein.

[0160] S207. When the AGV vehicle body changes from the initial movement type to the transitional movement type, determine whether each steering wheel has stopped rotating and whether the current steering angle corresponding to each steering wheel is consistent with the final steering angle corresponding to each steering wheel.

[0161] Among them, the steering wheel stopping rotating means that the traveling motor of the steering wheel is in a stopped state. The current steering angle refers to the real-time steering angle of the steering wheel. The final steering angle refers to the target steering angle calculated in step S205. The consistency judgment refers to comparing whether the error between the current steering angle and the final steering angle of the same steering wheel is within the allowable range.

[0162] Specifically, after the AGV vehicle body enters the transitional movement type, the control system needs to make two judgments: First, check whether all the traveling motors of the steering wheels have stopped rotating, which can be confirmed by reading the speed signal fed back by the encoder; then, perform a steering angle consistency check on each steering wheel, compare the real-time fed-back current steering angle with the calculated final steering angle. If the angle errors of all steering wheels are within the allowable range (for example, ±0.5 degrees), it is determined to be consistent. For example, if the final steering angle of a certain steering wheel is 45 degrees and the current steering angle is 44.8 degrees, with an error of 0.2 degrees within the allowable range, it is determined to be consistent.

[0163] S208. If so, switch the motion state of the AGV vehicle body to the execution state, and control each steering wheel to perform corresponding motions according to the final motion type and the speed-limited motion angular velocity.

[0164] Among them, the execution state refers to the state in which the AGV vehicle body can execute the target motion instruction. The final motion type refers to the target motion state that the AGV vehicle body needs to reach.

[0165] Specifically, when all the judgment conditions in step S207 are satisfied, the control system switches the state of the AGV vehicle body to the execution state. In the execution state, the control system sets the motion parameters of each steering wheel according to the final motion type, including rotational speed, direction, etc., while ensuring that the motion angular velocity of the whole vehicle does not exceed the speed-limited motion angular velocity. For example, when the final motion type is forward motion (if the motion angular velocity is zero), each steering wheel will start synchronously and maintain the same linear velocity; when the final motion type is forward motion and the motion angular velocity is not 0, the inner and outer steering wheels will operate at different speed ratios, and ensure that the steering angles of each steering wheel are coordinated (the perpendicular lines of the steering angles intersect at the rotation point).

[0166] S209. If not, keep the motion state of the AGV vehicle body in the initialization state, control the AGV vehicle body to execute the parking instruction, and drive each steering wheel to rotate to the angle position corresponding to the final steering angle.

[0167] Among them, the initialization state refers to the state in which the AGV vehicle body is in the preparation stage. The parking instruction is a control command that makes the AGV vehicle body stop moving. Driving each steering wheel to rotate to the angle position corresponding to the final steering angle means controlling each steering wheel to adjust to the target rotation angle through the steering wheel steering motor.

[0168] Specifically, when any of the judgment conditions in step S207 is not satisfied, the control system will take the following measures: First, keep the AGV vehicle body in the initialization state, indicating that it is not ready to execute a new motion instruction; then issue a parking instruction to ensure that the walking motors of all steering wheels stop running; finally, control the steering motors of each steering wheel to gradually adjust the steering angle of the steering wheel to the final steering angle position. For example, if the current angle of a certain steering wheel is 30 degrees and the final steering angle is 60 degrees, the control system will control the steering wheel to turn at an appropriate speed (such as 20 degrees per second) until the target steering angle is reached.

[0169] The following describes the control system in the embodiment of the present invention application from the perspective of hardware processing. Please refer to Figure 3 , which is a schematic structural diagram of an entity device of the control system in the embodiment of the present application.

[0170] It should be noted that Figure 3 The structure of the control system shown is only an example, and should not bring any limitations to the functions and usage scopes of the embodiments of the present invention.

[0171] As Figure 3 shown, the control system includes a CPU 301 which can perform various appropriate actions and processes according to a program stored in a read-only memory ROM 302 or a program loaded into a random access memory RAM 303 from a storage section 308, such as performing the method described in the above embodiments. In the RAM 303, various programs and data required for system operation are also stored. The CPU 301, ROM 302, and RAM 303 are connected to each other via a bus 304. An I / O interface 305 is also connected to the bus 304.

[0172] The following components are connected to the I / O interface 305: an input section 306 including an audio input device, a button switch, etc.; an output section 307 including a liquid crystal display (LCD), an audio output device, an indicator light, etc.; a storage section 308 including a hard disk, etc.; and a communication section 309 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 309 performs communication processing via a network such as the Internet. A drive 310 is also connected to the I / O interface 305 as needed. A removable medium 311, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is mounted on the drive 310 as needed so that a computer program read from it can be installed into the storage section 308 as needed.

[0173] Specifically, according to an embodiment of the present invention, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present invention includes a computer program product which includes a computer program carried on a computer-readable medium, and the computer program includes a computer program for performing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network via the communication section 309, and / or installed from the removable medium 311. When the computer program is executed by the CPU 301, various functions defined in the present invention are performed.

[0174] It should be noted that specific examples of computer-readable storage media may include, but are not limited to: electrical connections with one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fibers, portable compact disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above. In the present invention, a computer-readable storage medium can be any tangible medium that contains or stores a program, and this program can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0175] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present invention. Among them, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the above-mentioned module, program segment, or part of code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order from that marked in the accompanying drawings.

[0176] Specifically, the control system of this embodiment includes a processor and a memory. A computer program is stored on the memory. When the computer program is executed by the processor, it implements the AGV chassis steering wheel motion control method provided in the above embodiment.

[0177] On the other hand, the present invention also provides a computer-readable storage medium, which may be included in the control system described in the above embodiment; or it may exist alone and not be assembled into the control system. The above storage medium carries one or more computer programs. When the above one or more computer programs are executed by a processor of the control system, the control system is enabled to implement the AGV chassis steering wheel motion control method provided in the above embodiment.

[0178] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the various embodiments of the present application.

[0179] As used in the foregoing embodiments, depending on the context, the term "when" may be interpreted to mean "if", "after", "in response to determining", or "in response to detecting". Similarly, depending on the context, the phrase "upon determining" or "if (the stated condition or event) is detected" may be interpreted to mean "if determined", "in response to determining", "when (the stated condition or event) is detected", or "in response to detecting (the stated condition or event)".

[0180] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the foregoing embodiments can be implemented by a computer program instructing relevant hardware. The program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the foregoing method embodiments. The foregoing storage medium includes various media that can store program codes, such as ROM, random access memory (RAM), magnetic disks, or optical discs.

Claims

1. An AGV chassis steering wheel motion control method, characterized in that, Applied to a control system, the method includes: Taking the center point of the contour of the AGV vehicle body as the origin, an AGV vehicle body coordinate system is established. In the AGV vehicle body coordinate system, the forward direction of the AGV vehicle body is the positive direction of the X-axis, and the direction obtained by rotating 90 degrees counterclockwise from the positive direction of the X-axis is the positive direction of the Y-axis; Obtain the AGV chassis layout parameters and the initial motion speed of the AGV chassis in the AGV vehicle body coordinate system, and determine the initial motion type of the AGV chassis according to the initial motion speed. The AGV chassis layout parameters are used to represent the position coordinates of each steering wheel in the AGV chassis relative to the origin. The initial motion speed includes the initial motion speed in the X-axis direction, the initial motion speed in the Y-axis direction, and the initial motion angular velocity; Calculate the transitional motion type of the AGV vehicle body from the initial motion type to the final motion type. The transitional motion type is used to represent the temporary motion type of the AGV vehicle body during the motion type switching process. The initial motion type and the final motion type are different motion types; Based on the transitional motion type and the preset AGV acceleration and deceleration parameters, update the real-time motion speed of the AGV chassis, and determine the real-time motion type of the AGV chassis according to the real-time motion speed; When the real-time motion type is the final motion type, calculate the change amount of the turning radius and the change amount of the steering angle of each steering wheel from the initial motion type to the final motion type. The change amount of the turning radius is the path radius change amount of the turning radius of each steering wheel changing from the initial motion type to the final motion type, and the change amount of the steering angle is the angle change amount of the steering angle of each steering wheel rotating from the initial motion type to the final motion type; Based on the change amount of the turning radius, the change amount of the steering angle, and the AGV chassis layout parameters, calculate the motion direction of each steering wheel at a preset moment; The calculating the motion direction of each steering wheel at a preset moment based on the change amount of the turning radius, the change amount of the steering angle, and the AGV chassis layout parameters specifically includes: calculating the predicted position coordinates of the AGV chassis at the preset moment according to the real-time motion speed of the AGV chassis; determining the first predicted position reached by each steering wheel at the preset moment in the forward rotation case and the second predicted position reached by each steering wheel at the preset moment in the reverse rotation case based on the change amount of the turning radius, the change amount of the steering angle, and the AGV chassis layout parameters; determining the rotation direction of each steering wheel according to the distances from the first predicted position and the second predicted position to the predicted position coordinates respectively; The determining the rotation direction of each steering wheel according to the distances from the first predicted position and the second predicted position to the predicted position coordinates respectively specifically includes: determining the first distance according to the first predicted position and the predicted position coordinates, and determining the second distance according to the second predicted position and the predicted position coordinates; when the first distance is less than or equal to the second distance, it is determined to be in forward rotation; when the first distance is greater than the second distance, it is determined to be in reverse rotation.

2. The method according to claim 1, wherein Before the step of calculating the transitional motion type of the AGV vehicle body from the initial motion type to the final motion type, the method further includes: If the AGV vehicle body performs a lateral movement from the initial motion type to the final motion type, calculate the minimum turning radius allowed for the AGV vehicle body according to the AGV chassis layout parameters; Judge whether it is necessary to limit the motion angular velocity according to the minimum turning radius; If it is necessary to limit the motion angular velocity, calculate the speed-limiting motion angular velocity so that the motion angular velocity of the AGV vehicle body does not exceed the speed-limiting motion angular velocity during the motion type switching process.

3. The method according to claim 2, characterized in that, After the step of if it is necessary to limit the motion angular velocity, calculate the speed-limiting motion angular velocity so that the motion angular velocity of the AGV vehicle body does not exceed the speed-limiting motion angular velocity during the motion type switching process, the method further includes: Calculate the position of the rotation point of the motion trajectory in the AGV vehicle body coordinate system according to the final motion type and the final motion speed in the X-axis direction, the final motion speed in the Y-axis direction, and the speed-limiting motion angular velocity input; Based on the position of the rotation point, calculate the respective final steering angles of the respective steering wheels.

4. The method according to claim 3, characterized in that, After the step of calculating the transitional motion type of the AGV vehicle body from the initial motion type to the final motion type, the method further includes: When the AGV vehicle body changes from the initial motion type to the transitional motion type, judge whether the respective steering wheels stop rotating and whether the current steering angles corresponding to the respective steering wheels are consistent with the respective final steering angles; If so, switch the motion state of the AGV vehicle body to the execution state, and control the respective steering wheels to perform corresponding motions according to the final motion type and the speed-limiting motion angular velocity; If not, keep the motion state of the AGV vehicle body as the initialization state, control the AGV vehicle body to execute the parking instruction, and drive the respective steering wheels to rotate to the angular positions corresponding to the final steering angles.

5. The method according to claim 1, wherein The real-time motion types include parking, forward, backward, left shift, right shift, left front diagonal, right front diagonal, left rear diagonal, right rear diagonal, counterclockwise in-situ rotation, and clockwise in-situ rotation.

6. A control system, characterized in that, The control system includes: one or more processors and a memory; the memory is coupled to the one or more processors, the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to enable the control system to execute the method according to any one of claims 1 to 5.

7. A computer-readable storage medium, comprising instructions, characterized in that, When the instruction runs on the control system, enable the control system to execute the method according to any one of claims 1 to 5.

8. A computer program product, characterized in that, When the computer program product runs on the control system, enable the control system to execute the method according to any one of claims 1 to 5.

Images