CN-121995921-A - Control method for split AGV for vehicle transportation

CN121995921ACN 121995921 ACN121995921 ACN 121995921ACN-121995921-A

Abstract

The invention relates to the technical field of industrial logistics intellectualization, in particular to a control method of a vehicle carrying split AGV, which comprises the steps of S1, constructing a whole vehicle rigid body model, S2, executing S3 aiming at path tracking of an expected straight line driving track, S4 aiming at path tracking of an expected circular arc driving track, S3, correcting transverse errors of the whole vehicle rigid body model and a planned path through normal deviation correction and PID adjustment of the path direction to obtain linear angular velocity, S5, S4, integrating ideal angular velocity, course correction and radial correction to obtain circular arc angular velocity, S5 and S5, wherein a main vehicle sends a whole vehicle movement instruction to a slave vehicle through a network communication protocol, the main vehicle and the slave vehicle respectively calculate the whole vehicle movement instruction based on the whole vehicle rigid body model, and the main vehicle and the slave vehicle mutually confirm survival states through periodic heartbeat packets during communication. The invention can give consideration to tracking real-time performance and tracking precision and ensure communication robustness.

Inventors

HUANG ZHIFENG
Hong Xianlin
CHEN JINLONG

Assignees

九星国际物流(广州)有限公司

Dates

Publication Date: 20260508
Application Date: 20260206

Claims (10)

1. The control method of the split AGV for carrying the vehicle is characterized by comprising the following steps of: s1, respectively constructing steering wheel kinematic models of a main vehicle (200) and a slave vehicle (300) in a split AGV device (100), and constructing a whole vehicle rigid body model by taking the midpoints of the main vehicle (200) and the slave vehicle (300) as centers; S2, executing a step S3 aiming at the path tracking of the expected straight running track when the split AGV device (100) performs the path tracking motion; s3, correcting the transverse error of the whole rigid body model and the planned path through normal deviation correction and PID regulation with the path direction to obtain an actual direction vector of the whole rigid body model, obtaining an actual movement speed based on the actual direction vector, and obtaining a linear angular velocity through PID regulation on the attitude error of the actual movement speed; S4, planning an expected circular arc running track, obtaining an ideal angular velocity based on an ideal kinematic relation, obtaining a heading error and a radial error based on the current position of the rigid body model of the whole vehicle and the planned expected circular arc running track, and obtaining a heading correction amount and a radial correction amount through PID adjustment; S5, after the main vehicle (200) receives the whole vehicle movement instruction, the main vehicle (200) sends the whole vehicle movement instruction to the auxiliary vehicle (300) through a network communication protocol, the main vehicle (200) and the auxiliary vehicle (300) respectively calculate the whole vehicle movement instruction based on the whole vehicle rigid body model to obtain the movement state of a rudder group in a corresponding steering wheel kinematic model, and the survival state is mutually confirmed between the main vehicle (200) and the auxiliary vehicle (300) through periodically receiving and transmitting heartbeat packets during the communication between the main vehicle (200) and the auxiliary vehicle (300).
2. The method according to claim 1, characterized in that in step S1, in the whole vehicle rigid body model, when the split AGV device (100) is wound around a fixed point Radius of the process is The linear velocity is During the winding movement of (a) can be obtained: in the formula, Represents angular velocity; In a steering wheel kinematic model of a main vehicle (200), the main vehicle (200) is provided with a first steering wheel group (210) and a second steering wheel group (220), and the center point of the first steering wheel group (210) is set as Center point The linear velocity and deflection angle are respectively 、 Setting the center point of the second rudder unit (220) as Center point The linear velocity and deflection angle are respectively 、 From this, it is possible to obtain: in the formula, Represents the distance between any rudder set and the center of the rigid body model of the whole vehicle in the horizontal direction, The distance between the center point of any steering wheel group in the steering wheel kinematic model and the geometric center is represented, and the following can be obtained: the method comprises the following steps of: in the formula, Representing the center point To a fixed point Is used for the distance of (a), Representing the center point To a fixed point Is a distance of (2); in a steering wheel kinematic model of a slave vehicle (300), the slave vehicle (300) is provided with a third steering wheel group (310) and a fourth steering wheel group (320), and the center point of the third steering wheel group (310) is set as Center point The linear velocity and deflection angle are respectively 、 Setting the center point of the fourth rudder unit (320) as Center point The linear velocity and deflection angle are respectively 、 According to the symmetrical arrangement of the slave vehicle (300) and the master vehicle (200), the following steps are obtained: 。
3. the method of controlling a split AGV for vehicle transport according to claim 2, wherein step S3 includes the steps of: S31, dispersing the planned straight line path into a path point sequence, wherein the path point sequence comprises a plurality of path points; s32, obtaining a transverse error based on the vertical distance between the current position of the whole vehicle rigid body model and the planned straight line path, and obtaining a correction direction vector based on the path direction vector, wherein the correction direction vector is used for correcting the transverse error The deviation rectifying direction vector points to the path direction vector vertically; S33, inputting the transverse error into a PID controller for calculation to obtain a weighting coefficient for balancing path tracking and error correction, and weighting and synthesizing a path direction vector and a deviation correcting direction vector through the weighting coefficient to obtain an actual direction vector of the whole vehicle rigid body model; S34, performing unitization processing on the actual direction vector, mapping a target speed value to the unitized actual direction vector to obtain an actual movement speed, obtaining a target orientation angle of the whole vehicle rigid body model through a speed component of the actual movement speed in the axial direction, calculating an attitude error of the current orientation angle and the target orientation angle of the whole vehicle rigid body model, and inputting the attitude error into a PID controller for calculation to obtain a linear angular speed; S35, outputting the expected linear velocity and the linear angular velocity as whole vehicle motion instructions.
4. The method of controlling a split AGV for vehicle transport according to claim 3, wherein in step S31, the path direction vector The method comprises the following steps: Wherein: in the formula, Representing the current position coordinates of the whole vehicle rigid body model under the world coordinate system, Representing the coordinates of the next path point to be reached by the whole vehicle rigid body model in the planned path point sequence, Linear equation expression for representing coordinates of next path point and coordinates of current position of whole vehicle rigid body model Is a slope of (a); In step S32, the lateral error The method comprises the following steps: The deviation rectifying direction vector The method comprises the following steps: Wherein: Deviation correcting direction vector The direction of (2) is determined by the relative position of the whole rigid body model and the planned path: in the formula, Representing slope Is a normal slope of (c).
5. The method of controlling a split AGV for vehicle transport according to claim 4, wherein in step S33, the weighting coefficient is The method comprises the following steps: in the formula, Respectively represent the transverse errors Proportional, integral, differential parameters; The actual direction vector E of the whole vehicle rigid body model is as follows: in the formula, Indicating the deviation rectifying direction vector, The direction vector of the path is represented, Represents the weighting coefficient and 。
6. The method of controlling a split AGV for vehicle transport according to claim 5, wherein in step S34, the actual movement speed The method comprises the following steps: in the formula, Represents the expected linear velocity of the rigid body model of the whole vehicle, The actual direction vector is represented as such, Represents the actual direction vector after unitization, Respectively represent At the position of A shaft(s), A velocity component on the shaft; The linear angular velocity The method comprises the following steps: Wherein: in the formula, The posture error is represented by the difference in the posture, Indicating the current angle of orientation, Representation by The obtained target orientation angle; respectively represent attitude errors Proportional, integral, differential parameters; in the step S35 of the process of the present invention, In the formula, The linear angular velocity is indicated as such, Indicating the desired linear velocity.
7. The method of controlling a split AGV for vehicle transport according to claim 1, wherein step S4 includes the steps of: s41, planning an expected arc running track to obtain the circle center position, the arc radius, the arc winding direction and the expected arc linear speed of the expected arc running track, and obtaining an ideal angular speed based on an ideal kinematic relation; S42, obtaining a polar angle and an ideal course angle based on the current position of the whole vehicle rigid body model and the planned expected arc running track, obtaining a course error based on the ideal course angle and the polar angle, and then inputting the course error into a PID controller to eliminate the error, so as to obtain a course correction quantity; s43, obtaining radial errors based on the current position of the whole vehicle rigid body model and the planned expected circular arc running track, and then inputting the radial errors to a PID controller to eliminate errors, so as to obtain radial correction quantity; S44, integrating the ideal angular velocity, the course correction and the radial correction to obtain the circular arc angular velocity; s45, outputting the expected circular arc linear velocity and the circular arc angular velocity as a whole vehicle movement instruction.
8. The method of controlling a split AGV for vehicle transport according to claim 7, wherein in step S41, the center position of the desired circular arc travel path is Radius of arc is The direction around the circular arc is The expected circular arc linear velocity is Wherein, the method comprises the steps of, Ideal angular velocity The method comprises the following steps: In step S42, polar angle The method comprises the following steps: in the formula, Representing the current position coordinates of the whole vehicle rigid body model under a world coordinate system; according to the ideal course angle Angle with polar angle The ideal course angle can be obtained by orthogonal relation: Available heading error The method comprises the following steps: in the formula, Representing a current orientation angle; Error of course Inputting the corrected heading quantity into PID controller The method comprises the following steps: in the formula, 、 Respectively represent course errors Proportional controller parameter, differential controller parameter.
9. The method of controlling a split AGV for vehicle transport according to claim 8, wherein in step S43, the radial error is The distance between the rigid body model of the whole vehicle and the circle center position is the difference value between the distance and the arc radius: Wherein when When the whole rigid body model is outside the expected circular arc running track, and when When the whole vehicle rigid body model is positioned at the inner side of the expected circular arc running track; Will be radial error Inputting the corrected heading quantity into PID controller The method comprises the following steps: in the formula, 、 Respectively represent radial errors Proportional controller parameters, differential controller parameters; in step S44, the angular velocity of the circular arc The method comprises the following steps: In the step S45 of the process of the present invention, In the formula, The angular velocity of the circular arc is represented, Indicating the desired arc speed.
10. The control method of a split AGV for vehicle handling according to any one of claims 1 to 9, wherein in step S5, the network communication protocol is a TCP protocol, the master vehicle (200) is a client in the TCP protocol, and the slave vehicle (300) is a server in the TCP protocol, wherein: in the host vehicle (200): The client creates a socket; the client applies for connecting the server, if the connection fails, the resources of the connection application are cleared, and then the connection is carried out again until the connection is successful; After the connection is successful, starting a double thread, wherein one thread performs data transmission and processing with the server, including resolving the whole vehicle motion instruction and sending the whole vehicle motion instruction to the server, and also including receiving a slave vehicle control state, and the other thread performs heartbeat detection at each interval Second, sending a heartbeat packet to the server side; in the slave vehicle (300): the server creates an active socket; The server judges whether the needed connection port is occupied, if so, the process occupying the port is terminated forcefully, otherwise, the port and IP address binding operation is carried out; after binding is completed, starting a monitoring port, converting an active socket into a passive socket, and waiting for the connection of the client; After the client is connected, starting a double thread, wherein one thread is used for carrying out data transmission and processing with the client, and comprises the steps of resolving the whole vehicle motion instruction sent by the client and sending a slave vehicle control state to the client; and the other thread carries out heartbeat detection, resets a heartbeat timer after receiving the heartbeat packet of the client, if so If the next heartbeat packet is not received within seconds, the time is considered to be overtime, the resource is cleared, and then a reconnection state is entered, wherein, 。

Description

Control method for split AGV for vehicle transportation Technical Field The invention relates to the technical field of industrial logistics intellectualization, in particular to a control method of a vehicle carrying split type AGV. Background In the fields of modern manufacturing industry, logistics industry, intelligent parking lots and the like, vehicle transportation is one of very important working links. Along with the continuous evolution of automation technology, traditional manual handling mode is being accelerated to automation, intelligent mode conversion, and wherein integral AGV, split type AGV support as important intelligent equipment, can practice thrift the human cost, promotes work efficiency. The conventional AGV motion tracking algorithm comprises a pure tracking algorithm, a model prediction control algorithm, a linear quadratic regulator algorithm and the like, wherein the model prediction control algorithm and the linear quadratic regulator algorithm have remarkable advantages in control precision and dynamic performance, but the dependence and calculation complexity of the algorithms on a mathematical model also bring challenges in practical application, higher calculation resource requirements are required, the pure tracking algorithm is simple and easy to realize, but the tracking precision of the pure tracking algorithm is highly dependent on the selection of a pre-aiming distance, the self-adaptive adjustment is difficult to realize under a dynamic scene, path deviation is easy to cause, and for the split AGV, the common tracking algorithm is difficult to ensure consistency of cooperative motion, and tracking instantaneity and tracking precision cannot be considered. Disclosure of Invention The invention aims to overcome the defect that the tracking algorithm of the split AGV is difficult to consider tracking instantaneity and tracking accuracy in the prior art, and provides a control method for carrying the split AGV by a vehicle, which can consider tracking instantaneity and tracking accuracy and ensure communication robustness. In order to solve the technical problems, the invention adopts the following technical scheme: the control method for the vehicle carrying split AGV comprises the following steps: S1, respectively constructing steering wheel kinematic models of a main vehicle and a secondary vehicle in a split AGV device, and constructing a whole vehicle rigid body model by taking the midpoints of the main vehicle and the secondary vehicle as centers; S2, executing a step S3 aiming at the path tracking of the expected straight running track when the split AGV device performs the path tracking motion; s3, correcting the transverse error of the whole rigid body model and the planned path through normal deviation correction and PID regulation with the path direction to obtain an actual direction vector of the whole rigid body model, obtaining an actual movement speed based on the actual direction vector, and obtaining a linear angular velocity through PID regulation on the attitude error of the actual movement speed; S4, planning an expected circular arc running track, obtaining an ideal angular velocity based on an ideal kinematic relation, obtaining a heading error and a radial error based on the current position of the rigid body model of the whole vehicle and the planned expected circular arc running track, and obtaining a heading correction amount and a radial correction amount through PID adjustment; S5, after the host vehicle receives the whole vehicle movement instruction, the host vehicle sends the whole vehicle movement instruction to the slave vehicle through a network communication protocol, the host vehicle and the slave vehicle respectively calculate the whole vehicle movement instruction based on the whole vehicle rigid body model to obtain the movement state of a rudder wheel group in the corresponding rudder wheel kinematic model, and the host vehicle and the slave vehicle mutually confirm the survival state through periodically receiving and transmitting heartbeat packets during the communication between the host vehicle and the slave vehicle. The control method of the split AGV for carrying the vehicle comprises the steps of integrating a main vehicle and a slave vehicle of the split AGV device and constructing a unified whole vehicle rigid body model, so that the problem of motion fracture of the split AGV device can be avoided, setting different calculation rules aiming at the difference between a straight traveling track and an arc traveling track, combining a direction vector dynamic adjustment strategy and PID control aiming at path tracking of the expected straight traveling track, calculating ideal angular velocity, heading correction quantity and radial correction quantity and integrating the path tracking of the expected arc traveling track, effectively carrying out path tracking on the split AGV device, improving the robustness and tracking pr