An AGV logistics transport system and control method thereof

Abstract

The present invention discloses an AGV logistics transportation system and a control method thereof, wherein the AGV logistics transportation system comprises a transportation trolley and a guiding unit, wherein the transportation trolley is equipped with a control unit, a driving unit, a magnetic navigation signal sensor and an RFID reader, wherein the control unit is respectively connected with the driving unit, the magnetic navigation signal sensor and the RFID reader, and the guiding unit comprises a guiding magnetic strip and an RFID tag; the magnetic navigation sensor acquires the magnetic field signal of the guiding magnetic strip, and after the magnetic field signal is processed by the control unit, the driving unit is controlled to drive the transportation trolley to track along the guiding magnetic strip; the RFID reader transmits the read RFID tag data to the control unit, and the control unit controls the speed and direction of the transportation trolley according to the data, so that the transportation trolley finally arrives at the designated position accurately to realize material transportation.

Description

Technical Field

[0001] The present invention relates to the field of unmanned guided vehicles, and in particular to an AGV logistics transportation system and a control method thereof. Background Art

[0002] AGV (Automated Guided Vehicle), also known as driverless transport vehicle, is a transport vehicle equipped with electromagnetic or optical self-guiding devices, which can travel along a specified guide path and has safety protection and various transplanting functions. In industrial applications, the transport vehicle does not require a driver and uses rechargeable batteries as a power source. Generally, electromagnetic tracks are used to lay its route. The electromagnetic tracks are laid on the ground, and the AGV moves along the electromagnetic tracks. However, the AGV's operation along the electromagnetic track reduces its flexibility, and it is necessary to lay tracks, support brackets and other fixed devices, which are subject to more restrictions on sites, roads and space. If the AGV moves on wheels, although it makes its movement convenient and flexible, it is easy to deviate from the established route, accidents are prone to occur, and work efficiency is reduced. Summary of the invention

[0003] In view of the problems existing in the prior art, the purpose of the present invention is to provide an AGV logistics transportation system that enables an AGV vehicle to move on wheels and is not easy to deviate from a predetermined route, as well as a control method of the system.

[0004] In order to achieve the above-mentioned purpose, the present invention provides an AGV logistics transportation system, including a carrying cart and a guiding unit. A control unit, a driving unit, a magnetic navigation signal sensor and an RFID reader are installed on the carrying cart. The control unit is connected to the driving unit, the magnetic navigation signal sensor and the RFID reader respectively. The guiding unit includes a plurality of guiding magnetic strips and a plurality of RFID tags. The magnetic navigation sensor obtains the magnetic field signal of the guiding magnetic strip. After the magnetic field signal is processed by the control unit, the driving unit is controlled to drive the carrying cart to track along the guiding magnetic strip. The RFID reader transmits the read RFID tag data to the control unit, and the control unit controls the speed and direction of the carrying cart according to the data, so that the carrying cart finally reaches the designated position accurately to realize material transportation.

[0005] Furthermore, the guiding magnetic strip is laid on the ground to form a guiding route; the RFID tag is installed on the ground, and the RFID tag records the information of the running direction and speed of the transport vehicle.

[0006] Furthermore, the transport vehicle includes a chassis, a body, and a power supply unit, a control unit, a drive unit, a magnetic navigation signal sensor and an RFID reader installed thereon, wherein the body is installed above the chassis, and a loading device is provided on the top of the body for loading materials; a device area with a certain space is formed between the chassis and the body, and the power supply unit, the control unit and the drive unit are installed in the device area, the magnetic navigation sensor is installed on the front and rear sides of the chassis, and the RFID reader is installed on the right front side of the bottom of the chassis.

[0007] Furthermore, the control unit includes a PLC controller and a communication module. The PLC controller is connected to the drive unit, the magnetic navigation signal sensor, and the RFID reader. The magnetic navigation signal sensor transmits the received magnetic field signal to the PLC controller, and the RFID reader sends the information read on the RFID tag to the PLC controller. The PLC controller realizes communication connection with the outside world through the communication module to realize data interaction.

[0008] Furthermore, the control unit also includes a control panel, which is connected to the PLC controller. The control panel can issue instructions to the PLC controller and view the magnetic field signals collected in real time and the read RFID tag information.

[0009] Furthermore, the driving unit includes a driving wheel, a guide wheel, a servo driver, and a servo motor. The servo driver is connected to the servo motor, and the servo motor is connected to the guide wheel and the driving wheel. The servo driver is connected to the control unit. The control unit controls the operation of the servo motor by controlling the servo driver, and further controls the driving wheel and the guide wheel to achieve control of the transport vehicle.

[0010] Furthermore, the driving wheel is installed in the middle of the chassis to drive the transport vehicle forward; the guide wheels are installed at the four corners of the chassis to enable the transport vehicle to turn; the servo driver and servo motor are respectively installed on the chassis.

[0011] Furthermore, the present invention also includes a scheduling unit and a database. The scheduling unit is wirelessly connected to the control unit, and data between the two can be exchanged. The control unit transmits real-time data to the scheduling unit, and the scheduling unit issues instructions to the control unit based on these data to achieve remote control of the transport vehicle; the status and real-time position information of the transport vehicle are stored in the database so that the scheduling unit can analyze and process these data.

[0012] Furthermore, the control unit collects the magnetic field signal sensed by the magnetic navigation sensor, analyzes the state of the carrier on the guide magnetic strip, and adopts the PD control algorithm for correction control to prevent the carrier from deviating from the path guided by the guide magnetic strip; the PD control algorithm is an algorithm formed by combining proportional (P) control and differential (D) control, assuming that: u(t) represents the output signal; e(t) represents the input signal; Kp represents the proportional coefficient, Td represents the differential time constant, then the mathematical expression of proportional-differential control is: u(t)=Kpe(t)+KpTd*(de(t) / dt).

[0013] A control method for the above AGV logistics transport system, the steps are as follows:

[0014] (1) Start the transport vehicle, the magnetic navigation sensor obtains the magnetic field signal of the guide magnetic strip and transmits the signal to the control unit;

[0015] (2) The control unit determines the deviation of the position of the transport vehicle relative to the guide magnetic strip, and sends corresponding control instructions to the drive unit according to the relative position deviation;

[0016] (3) After receiving the control command, the drive unit controls the operation of the transport vehicle;

[0017] (4) The position of the transport vehicle relative to the magnetic strip changes, the magnetic field signal changes, and the magnetic navigation sensor continues to detect the magnetic field signal and feeds it back to the control unit:

[0018] (5) The control unit controls the driving unit to drive the transport vehicle to follow the guide magnetic strip through the above (1) to (4);

[0019] (6) When the transport vehicle is moving along the magnetic strip, the RFID reader transmits the read RFID tag data to the control unit, and the control unit controls the speed and direction of the transport vehicle based on the data;

[0020] (7) Before the transport vehicle runs to the designated location, it will first slow down when it detects a low-speed RFID tag, and then drive at an ultra-low speed after detecting the next ultra-low-speed RFID tag until the transport vehicle detects the stop RFID tag, ultimately allowing the transport vehicle to accurately reach the designated location and realize material transportation.

[0021] The present invention discloses an AGV logistics transport system, which enables a transport vehicle to track along a guide magnetic strip using a magnetic field signal obtained by a magnetic navigation sensor, and controls the speed and direction of the transport vehicle according to data of an RFID tag read by an RFID reader, so that the transport vehicle can accurately reach a designated location and realize material transportation.

[0022] The present invention has the following beneficial effects: the present invention adopts a PLC controller with high stability, and controls the operation of the transport trolley through signals obtained by a magnetic navigation sensor and an RFID reader; the present invention reads the data of the magnetic navigation sensor through a PD algorithm to correct the body state of the transport trolley, thereby ensuring the stable operation of the transport trolley along the guide magnetic strip; the present invention ensures the repeated point accuracy of the transport trolley through multi-speed operation; the dispatching unit of the present invention can issue instructions to the transport trolley according to the state of the transport trolley, and collect the real-time position of the transport trolley to avoid conflicts among multiple transport trolleys. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of the transport trolley of the present invention;

[0024] Figure 2 This is the closed-loop control logic diagram of the transport trolley of the present invention;

[0025] Figure 3 This is a flow chart of the dispatching unit of the present invention controlling the transport vehicle;

[0026] Figure 4 This is a diagram of the application of the transport trolley dispatching of the present invention. DETAILED DESCRIPTION

[0027] The present invention is described more fully below with reference to the accompanying drawings, in which exemplary embodiments of the present invention are shown. However, the present invention may be embodied in a variety of different forms and should not be construed as being limited to the exemplary embodiments described herein. Rather, these embodiments are provided so that the present invention is comprehensive and complete and fully conveys the scope of the present invention to those of ordinary skill in the art.

[0028] For ease of description, spatially relative terms such as "upper", "lower", "left", "right", etc. may be used herein to describe the relationship of one element or feature shown in the figure relative to another element or feature. It should be understood that, in addition to the orientation shown in the figure, the spatial terms are intended to include different orientations of the device in use or operation. For example, if the device in the figure is inverted, the elements described as being "below" other elements or features will be positioned "above" other elements or features. Therefore, the exemplary term "lower" can include both upper and lower orientations. The device can be positioned in other ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here can be interpreted accordingly.

[0029] like Figures 1 to 4 As shown, an AGV logistics transportation system of the present invention includes a transportation vehicle and a guiding unit. The transportation vehicle transports materials to a destination according to the guidance of the guiding unit.

[0030] The guiding unit includes a plurality of guiding magnetic strips laid on the ground and a plurality of RFID tags, wherein the guiding magnetic strips are laid on the ground to form a guiding route so that the transport vehicle can travel along the guiding route. The guiding magnetic strips can be laid on the ground by burying them in the ground surface, in which case the route is stable and not easily damaged, or by burying them in a carpet and then laying the carpet on the ground, in which case the route can be easily changed and the method is more flexible and convenient. Of course, the method is not limited to these two methods, and a suitable laying method can be selected according to actual conditions. The RFID tags are installed on the ground and set on both sides of the guiding route. The RFID tags record the operating information of the transport vehicle such as straight travel, turning, acceleration and deceleration, etc. The transport vehicle reads the information on the RFID tags and adjusts the operating speed and direction according to the information.

[0031] The transport vehicle includes a chassis 1, a body 2, a power supply unit 3, a control unit 5, a drive unit, a magnetic navigation signal sensor and an RFID reader 6, wherein the body 2 is installed above the chassis, and a loading device, such as a loading frame, a loading tray, etc., is arranged on the top of the body 2 for loading materials; a device area with a certain space is formed between the chassis 1 and the body 2, the power supply unit 3, the control unit 5, and the drive unit are installed in the device area, the magnetic navigation sensor is installed on the front and rear sides of the chassis 1, and the RFID reader 6 is installed on the right front side of the bottom of the chassis. In actual applications, these components installed on the chassis can select a suitable installation position according to actual conditions, and are not limited to the above description.

[0032] The power supply unit 3 provides electrical energy to various components of the transport vehicle and is a rechargeable and dischargeable battery.

[0033] The control unit 5 includes a PLC controller and a communication module. The PLC controller is connected to the drive unit, the magnetic navigation signal sensor, and the RFID reader. The magnetic navigation signal sensor transmits the magnetic field signal it receives to the PLC controller. After the signal is analyzed and processed by the PLC controller, the PLC controller controls the drive unit to operate, so that the transport vehicle can travel along the road paved with the guide magnetic strip without deviation, and the materials are delivered to the destination; the RFID reader sends the information read from the RFID tag to the PLC controller. After the signal is analyzed and processed by the PLC controller, the PLC controller controls the drive unit to enable the transport vehicle to accelerate, decelerate, stop, and other actions to ensure that the transport vehicle passes through each section safely to avoid collision with other devices; the PLC controller realizes communication connection with the outside world through the communication module to realize data interaction, such as wireless connection with smart terminals, scheduling units, and remote controllers. People can remotely control the PLC controller through smart terminals (smart phones, laptops, tablets, etc.), remote controllers, etc., to realize remote control of the transport vehicle. In addition, the control unit 5 also includes a control panel 4, which is connected to the PLC controller and installed on the side of the vehicle body 2. The control panel can be used to issue instructions to the PLC controller, and view the real-time collected magnetic field signals and read RFID tag information. It should be noted that the control panel does not have to be installed on the transport vehicle, but can also be installed in the monitoring room or on the wall for manual operation. In this case, the control panel is wirelessly connected to the PLC controller.

[0034] The driving unit includes a driving wheel 8, a guide wheel 10, a servo driver 9 and a servo motor 7. The servo driver 9 is connected to the servo motor 7, the servo motor 7 is connected to the guide wheel 10 and the driving wheel, and the servo driver 9 is connected to the PLC controller. The PLC controller controls the operation of the servo motor 7 by controlling the servo driver 9, and further controls the driving wheel 8 and the guide wheel 10 to control the running track and speed of the transport vehicle. Among them, the driving wheel 8 is installed in the middle of the chassis to drive the transport vehicle forward; the guide wheels are installed at the four corners of the chassis to enable the transport vehicle to turn; the servo driver 9 and the servo motor 7 are installed on the chassis respectively. In addition, the driving unit also includes a reducer and a fixed block. The reducer is installed between the servo motor and the driving wheel and the guide wheel. Because the rated speed of the servo motor is high, in order to ensure the safe and stable driving of the transport vehicle, the reducer is connected to the servo motor. Secondly, increasing the torque of the reducer will increase accordingly, thereby improving the transmission efficiency of the servo motor; the fixed block is installed on the driving wheel to ensure the stability of the transport vehicle, so that the driving wheel is firmly fixed on the frame to ensure the driving safety of the transport vehicle.

[0035] The magnetic navigation sensor forms a feedback signal by detecting the position of the magnetic field. The feedback magnetic field signal is compared with the magnetic field information of the original input end to form new control information. The new control information is processed by the PLC controller to form a control signal, thereby controlling the servo drive and servo motor, and then controlling the operation of the transport vehicle. The magnetic field information will change during the operation of the transport vehicle, and the magnetic navigation sensor will continue to detect the magnetic field signal and feedback, thus forming a closed-loop feedback control mode.

[0036] The control process of the entire navigation walking of the transport vehicle is:

[0037] (1) The magnetic navigation sensor detects the magnetic field signal and transmits the magnetic field signal to the PLC controller;

[0038] (2) The PLC controller determines the deviation of the position of the transport vehicle relative to the magnetic strip and sends corresponding control instructions to the servo driver based on the relative position deviation;

[0039] (3) After receiving the control command, the servo driver drives the servo motor to realize the actions of rotation, speed regulation, and stop, and the transport vehicle accordingly performs the actions of walking, turning, and stopping;

[0040] (4) After the servo motor is activated, the position of the transport vehicle relative to the magnetic strip changes, the magnetic field signal changes, and the magnetic navigation sensor continues to detect the magnetic field signal and feeds it back to the PLC. At this point, it returns to step (1), achieving closed-loop control.

[0041] Furthermore, the PLC controller collects the magnetic field signal sensed by the magnetic navigation sensor, analyzes the state of the transport vehicle on the guide magnetic strip, and uses the PD control algorithm for correction control to prevent the transport vehicle from deviating from the path guided by the guide magnetic strip. Specifically, the PD control algorithm is an algorithm formed by combining proportional (P) control and differential (D) control. The algorithm combines the characteristics of proportional control and differential control, and can reflect both the input signal and the differential of the input signal with respect to time. Assume that: u(t) represents the output signal; e(t) represents the input signal; Kp represents the proportional coefficient, and Td represents the differential time constant. The mathematical expression of proportional-differential control is:

[0042] u(t)=Kpe(t)+KpTd*(de(t) / dt)

[0043] Since the PD algorithm has a differential control unit, the PD algorithm can generate an effective correction signal in advance according to the change trend of the input signal of the magnetic navigation sensor, thereby improving the stability of the system. By judging the position deviation of the magnetic navigation sensor relative to the guide magnetic strip (that is, the body deviation of the transport vehicle), if there is a deviation, the PLC controller controls the operation of the drive unit to correct the transport vehicle.

[0044] In addition, the present invention also includes a dispatching unit, which is wirelessly connected to the control unit 5, and data can be exchanged between the two. The control unit 5 transmits real-time data to the dispatching unit, and the dispatching unit issues instructions to the control unit based on these data to realize remote control of the transport vehicle. The dispatching unit can be connected to the control units of multiple transport vehicles at the same time to realize the simultaneous dispatch of multiple transport vehicles, so that the transport vehicles can carry materials in a certain time sequence without accidents such as collisions. At this time, the present invention also includes a database, and the status and real-time location information of each transport vehicle are stored in the database so that the dispatching unit can analyze and process these data. The present invention can be operated as a single machine (not connected to the dispatching unit at this time), or it can be connected to various processing and production processes through the dispatching unit (connected to the dispatching unit at this time) to perform fast and accurate transportation work.

[0045] The present invention discloses an AGV material transport system. After the transport vehicle is started, it runs along the guide magnetic strip through the magnetic navigation sensor. During the operation, the RFID reader reads the information in the RFID tags along the way. The PLC controller controls the vehicle to go straight, turn, accelerate or decelerate according to the read data. When the vehicle arrives near a specified position, the RFID reader reads the data of the deceleration RFID tag, and the transport vehicle decelerates. In order to ensure the repeated positioning accuracy, the RFID reader reads the deceleration RFID tag again, and the vehicle runs at an ultra-low speed. The positioning accuracy can reach within ±5mm.

[0046] When multiple transport carts work at the same time, the present invention includes a scheduling unit and a database. The scheduling unit collects the status of each transport cart into the database, and issues a start command to the transport cart that meets the requirements by analyzing the electromagnetic power, load capacity and other conditions of the transport cart. During the operation of the transport cart, the arrived position is fed back to the scheduling unit in real time, and the scheduling unit stores the real-time position of the transport cart in the database; the scheduling unit issues a start command to the next transport cart, and during the operation of the second transport cart, the operating position of the first car issued by the scheduling unit is analyzed to avoid conflicts between the cars and cause a collision.

[0047] In addition, the dispatching unit can communicate directly with multiple transport carts and PLCs of multiple processing stations through the dynamic link library. After the first processing station is ready, a call instruction is sent to the dispatching unit. The dispatching unit issues instructions based on the status of the transport cart, calls the transport cart that meets the requirements, starts and runs it, and after running to the first station, performs processing operations. After completion, it waits for the call signal of the next station and runs in sequence according to this process. Before the transport cart runs to the specified position, it will first slow down after detecting a low-speed RFID tag, and then drive at an ultra-low speed after detecting the next ultra-low-speed RFID tag until the transport cart detects the stop RFID tag and the transport cart stops. In this way, multi-speed control ensures the positioning accuracy of the transport cart and avoids interference between the mechanism and the transport cart during the operation of the processing station mechanism. During the operation of multiple transport vehicles, two or more transport vehicles may run to the same intersection or fork in the road. To avoid this situation, each transport vehicle feeds back the real-time running path to the dispatching unit and stores it in the database. The dispatching unit issues start and stop commands based on the position of each transport vehicle to avoid traffic jams.

[0048] The present invention discloses an AGV logistics transport system, which enables a transport vehicle to track along a guide magnetic strip using a magnetic field signal obtained by a magnetic navigation sensor, and controls the speed and direction of the transport vehicle according to data of an RFID tag read by an RFID reader, so that the transport vehicle can accurately reach a designated location and realize material transportation.

[0049] The present invention also discloses a control method for an AGV logistics transport system, the steps of which are as follows:

[0050] (1) Start the transport vehicle, the magnetic navigation sensor obtains the magnetic field signal of the guide magnetic strip and transmits the signal to the control unit;

[0051] (2) The control unit determines the deviation of the position of the transport vehicle relative to the guide magnetic strip, and sends corresponding control instructions to the drive unit according to the relative position deviation;

[0052] (3) After receiving the control command, the drive unit controls the operation of the transport vehicle;

[0053] (4) The position of the transport vehicle relative to the magnetic strip changes, the magnetic field signal changes, and the magnetic navigation sensor continues to detect the magnetic field signal and feeds it back to the control unit:

[0054] (5) The control unit controls the driving unit to drive the transport vehicle to follow the guide magnetic strip through the above (1) to (4);

[0055] (6) When the transport vehicle is moving along the magnetic strip, the RFID reader transmits the read RFID tag data to the control unit, and the control unit controls the speed and direction of the transport vehicle based on the data;

[0056] (7) Before the transport vehicle runs to the designated location, it will first slow down when it detects a low-speed RFID tag, and then drive at an ultra-low speed after detecting the next ultra-low-speed RFID tag until the transport vehicle detects the stop RFID tag, ultimately allowing the transport vehicle to accurately reach the designated location and realize material transportation.

[0057] The present invention has the following beneficial effects: the present invention adopts a PLC controller with high stability, and controls the operation of the transport trolley through signals obtained by a magnetic navigation sensor and an RFID reader; the present invention reads the data of the magnetic navigation sensor through a PD algorithm to correct the body state of the transport trolley, thereby ensuring the stable operation of the transport trolley along the guide magnetic strip; the present invention ensures the repeated point accuracy of the transport trolley through multi-speed operation; the dispatching unit of the present invention can issue instructions to the transport trolley according to the state of the transport trolley, and collect the real-time position of the transport trolley to avoid conflicts among multiple transport trolleys.

Claims

1. An AGV logistics transport system, characterized in that: It includes a transport trolley, a guide unit, a dispatch unit and a database. The transport trolley is equipped with a control unit, a drive unit, a magnetic navigation signal sensor and an RFID reader. The control unit is connected to the drive unit, the magnetic navigation signal sensor and the RFID reader respectively. The guide unit includes a plurality of guide magnetic strips and a plurality of RFID tags. The magnetic navigation signal sensor obtains the magnetic field signal of the guide magnetic strip. After the magnetic field signal is processed by the control unit, the drive unit is controlled to drive the transport trolley to run along the guide magnetic strip. The RFID reader transmits the read RFID tag data to the control unit. The control unit controls the speed and direction of the transport trolley according to the data, so that the transport trolley can reach the designated position accurately and realize material transportation. After the transport vehicle is started, it runs along the guide magnetic strip through the magnetic navigation signal sensor. During the operation, the RFID reader reads the information in the RFID tags along the way. The PLC controller controls the vehicle to go straight, turn, accelerate or decelerate according to the read data. When it arrives near the designated position, the RFID reader reads the data of the deceleration RFID tag, and the transport vehicle decelerates. In order to ensure the accuracy of repeated positioning, the RFID reader reads the deceleration RFID tag again and runs at ultra-low speed. The positioning accuracy is within ±5mm. When multiple transport vehicles are working at the same time, the dispatch unit collects the status of each transport vehicle into the database, analyzes the electromagnetic power and load capacity of the transport vehicle, and issues a start command to the transport vehicle that meets the requirements. During the operation of the transport vehicle, the arrived position is fed back to the dispatch unit in real time, and the dispatch unit stores the real-time position of the transport vehicle in the database; The dispatch unit issues a start command to the next transport vehicle. During the operation of the second transport vehicle, the second transport vehicle analyzes the operating position of the first vehicle issued by the dispatch unit to avoid conflicts between vehicles and collisions. The magnetic navigation signal sensor forms a feedback signal by detecting the magnetic field position. The feedback magnetic field signal is compared with the magnetic field information of the original input end to form new control information. The new control information is processed by the PLC controller to form a control signal, thereby controlling the servo drive and servo motor, and then controlling the operation of the transport vehicle. The magnetic field information will change during the operation of the transport vehicle, and the magnetic navigation signal sensor will continue to detect the magnetic field signal and feedback, thus forming a closed-loop feedback control mode; The dispatch unit communicates directly with multiple transport carts and PLC controllers of multiple processing stations through the dynamic link library; after the first processing station is ready, it sends a call command to the dispatch unit. The dispatch unit issues a command based on the status of the transport cart, calls the transport cart that meets the requirements, starts it and runs it, and after running to the first station, performs the processing operation. After completion, it waits for the call signal of the next station and runs in sequence according to this process; before the transport cart runs to the specified position, it will first slow down when it detects the deceleration RFID tag, and then slow down when it detects the deceleration RFID tag again. After signing, the vehicle will travel at an ultra-low speed until the transport vehicle detects the stop RFID tag and stops. This multi-speed control ensures the positioning accuracy of the transport vehicle and avoids interference between the mechanism and the transport vehicle during the operation of the processing station mechanism. During the operation of multiple transport vehicles, multiple transport vehicles may run to the same intersection or fork in the road. In order to avoid this situation, each transport vehicle feeds back the real-time path of the operation to the dispatching unit and stores it in the database. The dispatching unit issues start and stop commands based on the position of each transport vehicle to avoid traffic jams.

2. The AGV logistics transport system according to claim 1, characterized in that: The guide magnetic strip is laid on the ground to form a guide route; the RFID tag is installed on the ground, and the RFID tag records the information of the running direction and speed of the transport vehicle.

3. The AGV logistics transport system according to claim 1, characterized in that: The transport vehicle includes a chassis, a body, and a power supply unit, a control unit, a drive unit, a magnetic navigation signal sensor and an RFID reader installed thereon, wherein the body is installed above the chassis, and a loading device is provided on the top of the body for loading materials; a device area with a certain space is formed between the chassis and the body, and the power supply unit, the control unit and the drive unit are installed in the device area, the magnetic navigation signal sensor is installed on the front and rear sides of the chassis, and the RFID reader is installed on the right front side of the bottom of the chassis.

4. The AGV logistics transport system according to claim 1, characterized in that: The control unit includes a PLC controller and a communication module. The PLC controller is connected to the drive unit, the magnetic navigation signal sensor, and the RFID reader. The magnetic navigation signal sensor transmits the received magnetic field signal to the PLC controller, and the RFID reader sends the information read from the RFID tag to the PLC controller. The PLC controller realizes communication connection with the outside world through the communication module to realize data interaction.

5. The AGV logistics transport system according to claim 4, characterized in that: The control unit also includes a control panel, which is connected to the PLC controller. The control panel can issue instructions to the PLC controller and view the magnetic field signals collected in real time and the read RFID tag information.

6. The AGV logistics transport system according to claim 3, characterized in that: The driving unit includes a driving wheel, a guide wheel, a servo driver, and a servo motor. The servo driver is connected to the servo motor, and the servo motor is connected to the guide wheel and the driving wheel. The control unit controls the operation of the servo motor by controlling the servo driver, and further controls the driving wheel and the guide wheel to realize control of the transport vehicle.

7. The AGV logistics transport system according to claim 6, characterized in that: The driving wheel is installed in the middle of the chassis to drive the transport vehicle forward; the guide wheels are installed at the four corners of the chassis to enable the transport vehicle to turn; the servo driver and the servo motor are respectively installed on the chassis.

8. The AGV logistics transport system according to claim 1, characterized in that: The dispatching unit is wirelessly connected to the control unit, and data between the two can be exchanged. The control unit transmits real-time data to the dispatching unit, and the dispatching unit issues instructions to the control unit based on these data to achieve remote control of the transport vehicle; the status and real-time location information of the transport vehicle are stored in the database so that the dispatching unit can analyze and process these data.

9. The AGV logistics transport system according to claim 1, characterized in that: The control unit collects the magnetic field signal sensed by the magnetic navigation signal sensor, analyzes the state of the transport vehicle on the guide magnetic strip, and uses the PD control algorithm for correction control to prevent the transport vehicle from deviating from the path guided by the guide magnetic strip; the PD control algorithm is an algorithm formed by combining proportional (P) control and differential (D) control, assuming that: u(t) represents the output signal; e(t) represents the input signal; Kp represents the proportional coefficient, and Td represents the differential time constant, then the mathematical expression of proportional-differential control is: u(t)=Kpe(t)+KpTd*(de(t) / dt).

10. A control method for an AGV logistics transport system, the control method implementing the AGV logistics transport system according to any one of claims 1 to 9, the steps being as follows: (1) Start the transport vehicle, the magnetic navigation signal sensor obtains the magnetic field signal of the guide magnetic strip and transmits the signal to the control unit; (2) The control unit determines the deviation of the position of the transport vehicle relative to the guide magnetic strip, and sends corresponding control instructions to the drive unit according to the relative position deviation; (3) After receiving the control command, the drive unit controls the operation of the transport vehicle; (4) The relative position of the transport vehicle to the magnetic strip changes, the magnetic field signal changes, and the magnetic navigation signal sensor continues to detect the magnetic field signal and feeds it back to the control unit: (5) The control unit controls the driving unit to drive the transport vehicle to follow the guide magnetic strip through the above (1) to (4); (6) When the transport vehicle is moving along the magnetic strip, the RFID reader transmits the read RFID tag data to the control unit, and the control unit controls the speed and direction of the transport vehicle based on the data; (7) Before the transport vehicle runs to the designated location, it will first slow down after detecting the deceleration RFID tag, and then drive at an ultra-low speed after detecting the deceleration RFID tag again, until the transport vehicle detects the stop RFID tag, and finally the transport vehicle accurately reaches the designated location to realize material transportation.

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