Track logistics control system with high-reliability partition scheduling function

Abstract

The invention provides a rail logistics control system with a high-reliability partition scheduling function. Hardware equipment mainly comprises a master controller, a regional gateway, a shunt device, a track logistics trolley and the like. The system adopts a regional control mode, and the master controller is connected with each regional gateway through a wired optical cable to form a looped network, so that the communication stability is improved, and meanwhile, a redundancy function is also realized; the regional gateways communicate with equipment such as the rail logistics trolleys and the shunt devices in all regions, and the control center dispatches the logistics equipment in all the regions through the regional gateways, so that the function of regional dispatching is achieved; the interaction process between the trolley and the control center and between the shunt device and the control center adopts an autonomously designed high-reliability control mode, and comprises three parts of transmission mechanism establishment, communication protocol design and scheduling logic design. The method is reasonable in conception and flexible to use, can effectively solve the problems of low efficiency, low real-time performance, poor fault tolerance and the like of the existing rail logistics system, and improves the reliability of system operation.

Description

Technical Field

[0001] The present invention relates to the technical field of rail logistics transportation, and in particular to a rail logistics control system with a high-reliability zoning scheduling function. Technical Background

[0002] In buildings such as hospitals, libraries, and factories, traditional logistics and transportation methods are mainly based on manual operations, which is not only costly and inefficient, but also prone to errors and omissions, and can no longer meet the needs of modern logistics and transportation. With the rapid rise of information technology represented by digitalization and intelligence, various fully automated logistics and transportation systems have emerged. Rail logistics has become an innovative logistics and transportation method that leads the transformation and upgrading of logistics because of its many advantages.

[0003] The Track Vehicle System (TVS) generally plans tracks on the upper floors and shafts, and uses track logistics carts as the transportation carriers of materials to cope with logistics transportation tasks on the same floor, across floors, and across buildings. Currently, the track logistics transmission system has been operating in scenarios such as hospitals, libraries, and high-end smart manufacturing factories, and has become an important part of modern logistics automation technology.

[0004] As the scale and volume of buildings continue to expand, logistics and transportation tasks are increasing. However, my country's rail logistics and transportation system technology started late and developed slowly. The existing rail logistics and transportation systems have problems such as low scheduling efficiency and high failure rate during use. Therefore, a highly reliable and efficient rail logistics control system is urgently needed. Summary of the invention

[0005] The present invention provides a rail logistics control system with a high-reliability zoning scheduling function, aiming to improve the operating efficiency and reliability of the rail logistics transportation system.

[0006] The present invention first provides a system hardware control structure, the system includes a master controller, a regional gateway, a rail logistics trolley, and a switch;

[0007] The master controller is located in the control center, which is the dynamic dispatching, control and command center of the rail logistics system;

[0008] The control center can add related equipment with monitoring, communication and other functions according to demand, and the dispatch demand information issued by the staff is also received by the control center;

[0009] The regional gateway is a communication device for data transmission between the control center and the regional rail logistics equipment to achieve the purpose of zoning scheduling;

[0010] The rail logistics trolley is a carrier for transporting items in the system. The trolley runs on a track with a fixed electronic tag attached to the track. The car body is equipped with a reader / writer, and the reader obtains the current location by scanning the electronic tag.

[0011] The rail logistics trolley is equipped with a communication terminal, which exchanges information with the control center through the regional gateway;

[0012] The switch is used for path switching of the rail logistics trolley on the track. It has the same communication terminal as the trolley and is used for data interaction with the regional gateway.

[0013] The rail logistics trolley positioning method of the present invention adopts RFID, which uses the principle of electromagnetic induction to read information, can quickly obtain data without direct contact, and has a positioning accuracy of centimeters. The cost is relatively low, the tag can be reused, and the flexibility is strong, which meets the needs of the rail logistics system.

[0014] The RFID positioning system consists of two main parts: the RFID reader and the tag. The reader is a device that interacts with the tag. Its accuracy determines the accuracy of the system's vehicle location information.

[0015] The present invention selects a passive tag. The passive tag uses the electromagnetic field generated by the reader antenna, which is rectified by the magnetic field and then returns the tag signal. The passive tag has the advantages of small size, low cost and long life.

[0016] In order to enable the control center to accurately locate the position of the rail logistics trolley, the present invention divides the electronic tags into the following four categories according to the track position of the tag:

[0017] Class A tags represent the identification of the car about to enter or leave the switch: the car needs to interact with the control center when passing through each switch. In order to let the control center know that the car is about to pass through the switch, this type of tag is set. When the car is about to enter or leave the switch, it will read the tag and upload it to the control center to indicate that it is about to enter the switch. The control center will determine whether it needs to switch tracks according to the situation;

[0018] The B-type tag represents the parking position on the diverter. When the car completely enters the diverter and can start the diverter, the B-type tag will be recognized by the card reader. The system can judge the diverter progress of the car and monitor whether the diverter process is smooth.

[0019] Class C tags represent the "logistics station parking location" and other important station identifications, usually located at the end of the task. By reading these tags, the car can accurately identify its target location and complete the parking. At the same time, the control center can also track the car's driving trajectory and task completion status based on the reading information of these tags.

[0020] Class D tags are used on ordinary straight track sections. They are pasted on the track at a certain regular interval, so that the vehicle can continuously read and update its position information during driving. The coding design of this type of tag includes section identification information and a continuous number used to distinguish multiple tags on the same section. This design enables the control center to accurately calculate the position and speed of the vehicle based on the read tag information, thereby providing reliable data support for path planning and scheduling.

[0021] The rail logistics trolley of the present invention selects wireless communication as the communication mode between the rail logistics trolley and the control center, which can get rid of the constraints of physical lines and has the advantages of strong scalability and convenient maintenance. As for its transmission stability and weak anti-interference, the reliable transmission mechanism of the present invention can solve the problems.

[0022] The present invention adopts LoRa wireless communication, which has long-distance transmission, penetration capability, low power consumption, and low cost, and can adapt to application scenarios such as transmission between buildings.

[0023] The LoRa network is mainly composed of terminal nodes and LoRa regional gateways. The regional gateway is located at the core of the LoRa network and is responsible for direct information interaction with the host computer in the control center;

[0024] In the present invention, the LoRa gateway communicates with the control center through standard TCP / IP, wherein the LoRa gateway acts as a client, the control center acts as a server, and the LoRa terminal node is responsible for receiving information from the car controller and sending data to the LoRa gateway through the LoRa network;

[0025] The present invention takes into account the problems of many floors and a large usage range in actual scenarios, and uses Ethernet to transfer data;

[0026] The LoRa gateway is connected to the control center via TCP / IP. Different gateways have different IP addresses. The control center as the server can communicate with multiple gateways.

[0027] Each area in the building corresponds to a gateway, and the control center can obtain the location information of the car through the RFID tag, so as to determine which LoRa regional gateway to communicate through, so as to achieve the purpose of partition scheduling;

[0028] Each LoRa regional gateway in the present invention adopts a ring network connection structure, and there are two data transmission links between each gateway. When a certain area fails and is shut down for maintenance or a link is damaged, it will not affect the normal operation of other areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1The overall hardware structure diagram of the rail logistics control system of the present invention;

[0030] Figure 2 It is the control center software framework of the present invention;

[0031] Figure 3 Establish a process diagram for the reliable transport mechanism of rail logistics trolleys;

[0032] Figure 4 This is the state transformation model diagram of the rail logistics trolley;

[0033] Figure 5 Processing task instruction flow chart for rail logistics trolley;

[0034] Figure 6 This is a data interaction flow chart when the rail logistics vehicle passes through the switch;

[0035] Figure 7 Design diagram for data upload protocol of rail logistics trolley;

[0036] Figure 8 Send command classification diagram to the control center;

[0037] Fig. 9 Issue protocol design drawings for task instructions to the control center;

[0038] Fig.10 This is the logic diagram of the rail logistics trolley passing through the switch;

[0039] Fig.11 It is the interactive logic diagram of the rail logistics trolley passing through the switch;

[0040] Fig.12 This is the flow chart for rail logistics trolley scheduling. DETAILED DESCRIPTION

[0041] The high reliability control method proposed in the present invention will be technically described clearly and completely below in conjunction with the drawings in the present invention. All other embodiments obtained by those skilled in the art based on the embodiments in the present invention without making any creative work shall fall within the scope of protection of this application.

[0042] The high reliability control method proposed in the present invention mainly includes three parts: transmission mechanism establishment, communication protocol design and scheduling logic design;

[0043] The first step is to establish the transmission mechanism:

[0044] The control center of the present invention is the core component of the system, responsible for monitoring, dispatching and managing the operation of the entire rail logistics system. The main functions of the control center are:

[0045] Communicate and monitor with rail logistics trolleys, switchers and other equipment to dispatch trolleys and issue tasks, provide real-time status feedback of trolleys, and monitor the operating status of all rail trolleys in real time, including location, speed, power, status and other information, to ensure the normal operation of the system;

[0046] Regarding the dispatching of rail logistics vehicles, the control center will intelligently dispatch the vehicles according to the transportation needs and real-time status of the system to ensure that they are delivered to the destination on time, at the right place, and in the right quantity. The dispatching algorithm module usually considers factors such as path optimization, vehicle load balancing, and task priority.

[0047] Interacting with the logistics receiving and dispatching control station (monitoring APP), the control center needs to accept the material requirements issued by operators from various work stations through the logistics receiving and dispatching control station and send them to the rail logistics trolley;

[0048] In order to establish a reliable transmission mechanism, the present invention first designs a control center software framework Figure 2 As shown, it is divided into 8 modules, including switch status, track trolley status, track data module, database module, vehicle scheduling conflict module, task scheduling module, and optimal path module;

[0049] The shortest path from any two logistics receiving and dispatching sites is saved in the optimal path module so that it can be queried by other modules;

[0050] The vehicle scheduling conflict module will calculate the initial driving route based on the shortest path, whether the vehicle conflicts, etc., and send it to the track vehicle and the switch in the equipment control layer through the communication module;

[0051] The track data module stores the track information of the entire map, and can calculate the approximate position of the car based on the car's speed and present it to the 3D visualization platform;

[0052] During the operation of this system, the control center collects and processes a large amount of operation data, including the location information of the vehicle, task completion status, fault information, etc. These data need to be stored in the database. In this system, the SQLite database is used.

[0053] Since LoRa wireless communication is used between the rail logistics trolley and the control center of the present invention, the reliability of communication is the key to the normal operation of the rail logistics system. For this reason, the present invention designs a reliable transmission mechanism, and its establishment process is as follows: Figure 3 As shown;

[0054] The interaction process between the control center and the rail car is divided into three stages: connection establishment stage, interaction stage and disconnection stage;

[0055] After power-on initialization, the rail logistics trolley will automatically establish a connection with the control center. Under normal working conditions, once the connection is established, the rail trolley is in a state of accepting task commands from the control center at any time, and can report the status through the heartbeat cycle. At the same time, the trolley can also accept status inquiries from the control center at any time and report its own status.

[0056] If there is a communication failure or interference, the railcar may be disconnected from the control center. The railcar will try to reconnect to the control center at fixed intervals (for example, 3 seconds).

[0057] When reconnection fails, the control center will remind the operator to check the status of the car, and after the car is disconnected from the control center, it will prompt on the on-board display screen and light strip;

[0058] For the control center, it will not actively disconnect from the rail trolley under normal circumstances. However, if the control center times out when receiving the trolley's periodic status report or query feedback, the control center will consider the connection abnormal and wait for the trolley to reestablish the connection.

[0059] The control center must know the status of each trolley at this moment when scheduling, and when the status of the trolley changes, it must be uploaded to the upper control center in time. Based on this situation, the present invention designs 7 states of the rail logistics trolley:

[0060] 1 Idle state, indicating that the rail logistics vehicle currently has no tasks to execute or the tasks have been completed, waiting for the host computer to issue a dispatch command;

[0061] 2Task-carrying status, indicating that the rail logistics vehicle is carrying out the task;

[0062] 3 Emergency switch alarm: When the emergency switch button is pressed, the trolley motor power is disconnected and stops moving. Other devices are powered normally, and the trolley status changes to the emergency switch alarm status.

[0063] 4. Equipment failure status. The car may also have various abnormal conditions during driving. For example, if it receives failure information of the drive motor, RFID sensor and other equipment, the car will upload the equipment failure status to facilitate maintenance personnel to repair it.

[0064] 5 Low battery alarm state: when the battery power collected by the battery thread is less than 20%, the rail car will enter the low battery alarm state. When the current task of the car is completed, the control center will dispatch the car to the charging station for charging;

[0065] 6 Laser sensor alarm state: In order to prevent collisions between cars, a laser sensor is installed at the front and rear of each car. When the laser sensor detects an obstacle within the safe distance, it will alarm and the car will stop and wait;

[0066] 7. Edge-touch alarm state: when the trolley collides with an object by accident, the trolley stops moving and the state changes to edge-touch alarm state;

[0067] The state transformation diagram of the rail logistics trolley of the present invention is as follows: Figure 4 As shown in the figure, the initial state of each car after power-on is idle state. The car needs to wait for task scheduling from the control center. After the car receives the task scheduling task from the host computer, the car will change from idle state to task undertaking state. After the car completes the task, the car will return to idle state.

[0068] Whenever the car changes from one state to another, the status reporting thread will promptly update the status information to the host computer through the communication thread.

[0069] Figure 5 This is the process flow chart of the car receiving the protocol sent by the control center. After receiving the command sent by the control center, the car controller will judge the type of command sent by the control center in turn, make corresponding judgments, and finally send the results to the specified thread using the message queue;

[0070] For example, when the control center issues a motion start command, the car will determine what kind of command it is after receiving it. If it is a motion start command, it will send the result to the motion state thread, and the motion state thread will start the car.

[0071] When the control center dispatches cars, it usually dispatches idle cars to a certain station according to the shortest distance (or the least road section).

[0072] When the control center successfully sends a task scheduling instruction to the vehicle, the control center will maintain the task information (including the vehicle ID, starting node or path, passing path and nodes, and end node) and status, and the rail vehicle only needs to report the status;

[0073] When the car controller accepts a task, it needs to save the task command protocol information, and during the task execution, it needs to save and update the route card number;

[0074] When the car accepts a new task, the task is officially created, and the control center maintains the task status and records it in the database.

[0075] In the logistics track system, the control center relies on RFID tag information to determine the road sections and nodes. When the RFID card is read, the track car will report the latest location information so that the control center can update it. Figure 6 This is a data interaction flow chart when the car passes through the switch;

[0076] When the car reads the D-type ordinary road section label, the car's motion state does not need to change, but the location information must be updated to the control center;

[0077] When the car reads a Class C tag, the car controller will compare it with the terminal station information field in the protocol of the task sent by the car. If it is not the terminal station of the car, the track car will only update the location information to the control center. If it is the terminal station, it will stop and update the location information to the control center, and the car status will become idle.

[0078] Then comes the communication protocol design:

[0079] For rail logistics vehicles, information exchange between them and the control center is the key to the normal operation of the system. Specifically, there are two main information flows that together constitute a complete communication link between the rail vehicle and the control center:

[0080] First, the control center issues instructions to the rail trolley to achieve remote control of the trolley;

[0081] Second, the rail car uploads data to the control center to feedback the real-time status and location information of the car.

[0082] Among them, the car will upload data to the control center in the following four situations:

[0083] 1. The control center actively requests upload. When the control center finds that the uploaded data of the rail car is lost or abnormal, it will actively request the car to re-upload the relevant data. This situation usually occurs during the driving of the car. Due to communication interference, equipment failure or other reasons, the data transmission is interrupted or wrong. In order to restore the effective monitoring of the car, the control center will send instructions in time, requiring the car to re-upload its status, location and other key information;

[0084] 2. The car actively uploads after reading the RFID. Whenever the car passes an RFID tag, its built-in card reader will read the tag content and upload this information together with the current status of the car to the control center;

[0085] 3. The car state changes. There are seven states in total. After each state changes, the car will actively upload data to the control center to ensure that the control center is aware of the car state in a timely manner.

[0086] 4. Heartbeat cycle reporting. In order to ensure that the communication between the rail car and the control center remains stable and reliable, the system also introduces a heartbeat cycle reporting mechanism;

[0087] Under this mechanism, the rail car will regularly send heartbeat packets to the control center at preset time intervals, which contain the car's status and location information;

[0088] At the same time, the reporting time interval of the heartbeat cycle can be flexibly adjusted according to the actual operation status and needs of the system to achieve the best communication effect and performance;

[0089] The content of the data upload protocol of the rail logistics trolley of the present invention is as follows Figure 7 As shown (only includes the data segment content).

[0090] The instructions issued by the control center are divided into the following categories: Figure 8 The five categories shown in the figure, after the instruction is issued, the car communication thread is responsible for parsing the protocol sent by the control center and sending the parsed results to other threads through the message queue;

[0091] The status query command is the control center's request for the track car to upload information such as status and position, and the stop waiting command and motion start command are used to control the small movement to stop and move;

[0092] When the control center receives a low-battery alarm, it will issue an automatic charging command.

[0093] Task commands are instructions related to tasks, which can be divided into five types: empty vehicle dispatch, item delivery, pause task, resume task, and clear task;

[0094] The control center issues task command protocols such as Fig. 9 As shown, it includes task information field, switch information field, and terminal information field.

[0095] Finally, the scheduling logic design:

[0096] The operation logic of the trolley during the transfer process is the core link in the transportation of goods. The control center determines the location information of the transfer equipment through the FRID tag value uploaded by the rail logistics trolley and the transfer device. The present invention describes this process in detail, such as Fig.10 and Fig.11 As shown;

[0097] When the rail vehicle approaches the switch, it will determine whether the read Class A tag is a switch that the task needs to pass through. If it is determined that the switch is not on the path of the current task, the vehicle will pass through directly without switching operations;

[0098] If the task passes through the switch, the car will stop and wait for the control center to send command information, which includes whether the switch is occupied by other cars and whether the switch is parked at the entry point.

[0099] After receiving this information, the car will make judgments in turn and take corresponding actions based on the judgment results;

[0100] For example, if the switch is occupied, the car may need to wait; if the switch is at the entry point, the control center can perform the switch operation;

[0101] Except for the power-on initialization process, the diverter can only move after receiving the movement command from the control center at any other time. When the car passes through the diverter, the control center reads the Class A card of leaving the diverter through the car, and determines that the car has completely left the diverter. Only then is the diverter considered to be in idle state.

[0102] The scheduling planning system is a bridge between the control center and the rail logistics equipment. It is commanded by the control information of the control center and uses the rail logistics trolley to move on the dedicated track to realize the transportation of goods. This invention does not involve specific path planning algorithms, but only designs the main scheduling process such as Fig.12 As shown:

[0103] The staff first issues a dispatch request, and the control center assigns the nearest vehicle to transport the vehicle. It uses relevant algorithms to balance track congestion when multiple vehicles are running, and combines conflict resolution and coordination strategies to plan the best path for the vehicle.

[0104] The present invention has reasonable conception and flexible use, and can effectively solve the problems of low efficiency, low real-time performance, poor fault tolerance, etc. of the existing rail logistics system, thereby improving the reliability of system operation.

[0105] The embodiments of the present invention are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. For those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A rail logistics control system with high reliability zoning dispatching function, applied to rail logistics transportation system, wherein the system hardware part includes: Master controller, regional gateway, rail logistics trolley, and switch; The master controller is located in the control center, which is the dynamic dispatching, control and command center of the rail logistics system; The control center can add related equipment with monitoring, communication and other functions according to demand, and the dispatch demand information issued by the staff is also received by the control center; The regional gateway is a communication device for data transmission between the control center and the regional rail logistics equipment to achieve the purpose of zoning scheduling; The rail logistics trolley is a carrier for transporting items in the system. The trolley runs on a track with a fixed electronic tag attached to the track. The car body is equipped with a reader / writer, and the reader obtains the current location by scanning the electronic tag. The rail logistics trolley is equipped with a communication terminal, which exchanges information with the control center through the regional gateway; The switch is used for path switching of the rail logistics trolley on the track. It has the same communication terminal as the trolley and is used for data interaction with the regional gateway.

2. The system according to claim 1, characterized in that The three parts are transmission mechanism establishment, communication protocol design and scheduling logic design: The transmission mechanism first designs the control center software framework, then stipulates the process of establishing the reliable transmission mechanism of the car and the car state transition model, and finally designs the car processing task instruction flow and RFID data processing flow. The communication protocol design includes a rail logistics trolley data upload protocol and a control center task instruction issuance protocol. Before designing the control center task instruction issuance protocol, the instructions issued by the control center are classified. The scheduling logic includes the rail logistics trolley's path switching device logic and its data interaction logic, and finally the rail logistics trolley scheduling algorithm flow is designed.

Images