Laser Guided AGV System
Working Principle of Laser Guided AGV System
In its operating area, the AGV has a communication area and a non-communication area. In the communication area, the AGV communicates with the system control computer through its in-vehicle communication device, reports its position and status, and accepts work instructions. In the non-communication area, the AGV drives independently according to the predetermined program in the trolley controller, and does not communicate with the system control computer.
The working process is as follows: after receiving the cargo handling instruction, the trolley controller calculates and analyzes according to the stored operation map and the current position and driving direction of the AGV, selects the best driving route, and automatically controls the driving of the AGV through the drive amplifier. After reaching the accurate stop position of the loading target point, the transfer mechanism moves to complete the loading process. Then the AGV starts, drives to the target unloading point, and stops accurately, the transfer mechanism moves, completes the unloading process, and reports its position and status to the control computer. Then the AGV starts and drives to the standby area. After receiving a new order, do the next transportation.
During the driving process of the AGV, the laser scanning head on the vehicle continuously scans the surrounding environment, and when it scans the pre-set vertical reflector around the driving path, it "sees" the "road sign". As long as three or more reflectors are scanned, the AGV's current position in the global coordinate system can be calculated by the positioning computer based on their coordinate values and the azimuth angle of each reflector relative to the longitudinal axis of the vehicle body. The Y coordinate, and the angle between the current driving direction and the X axis of the coordinate system, realize accurate positioning and orientation.
Laser-guided AGV system system function
1. Scheduling Management
1.1 Task management: The tasks assigned by the upper scheduling computer are scheduled according to the time sequence and task priority.
1.2 Vehicle management: According to the position and state of the AGV at that time, select the idle car closest to the target point (including the calculation result of the weighted value of each road section) to perform the task.
1.3 Traffic management: Control and manage all AGVs within the jurisdiction. AGVs strictly follow the planned path, drive and operate independently of each other, and can yield vehicles to each other.
2. Communication Transmission
2.1 Keep in touch with the upper scheduling computer through the network, accept task scheduling, and report the execution results.
2.2 Maintain communication with each AGV through radio and direct vehicle operations.
2.3 Directly modify or update the control program of each AGV through radio communication.
2.4 It has the function of remote network communication transmission.
3. Control Management
3.1 Check the process of the vehicle executing the command.
3.2 Query vehicle status.
3.3 Query vehicle traffic management information, occupancy information of each point and segment.
3.4 Query data acquisition system signals.
3.5 Query data of global parameters.
3.6 Unblock the vehicle and check the occupancy information of each point.
3.7 Query the logical connection of the path (through the weight detection between each point), display, clear, and reload the parameter table.
3.8 Detect radio communication conditions.
3.9 Query the network connection with the upper scheduling computer.
3.10 Query the information about vehicle stop midway.
4. Graphical Monitoring
4.1 Display a system-wide path map, including individual points and segments.
4.2 Display the position and status of each AGV within the system. Common states are: normal state, waiting for charging, manual state, emergency stop state, path blockage, car lost, car stop, obstacle blocking, etc. Displays the occupancy information of each operating point and charging point.
4.3 Users or user groups with different operation rights for graphic monitoring can be established.
4.4 Reports such as event logs can be generated.
4.5 The monitoring graph can be scaled according to the definition, and the layer can be closed as needed.
4.6 It can display its information by defining the state of the vehicle.
4.7 View and set the status of input and output.
4.8 Check the command list in the command buffer to understand the specific loading and unloading locations of the AGV. The command list will be continuously updated according to the received status information, and a certain command can be deleted or local parameters can be changed.
4.9 Check the PLC status of the vehicle, track the specified vehicle, cancel the vehicle that is not in the system, and release the blockage between vehicles.
4.10 The system has event management function. Unexpected events can be reported, including AGVs waiting too long to charge; vehicles blocked for too long; lost navigation for too long; missions cancelled; invalid or wrong loading and unloading station numbers, etc. Event filters can be used to display only the event types or events that occurred within the time period that you want to query.
4.11 The task can be directly issued in the graphic monitoring (for emergency use).
5. Mode Selection
5.1 A variety of management modes can be set according to the actual needs of production. Such as centralized delivery, centralized return, normal work and rest, etc. Different modes have different priority scheduling functions.
5.2 Different priorities can be set according to production conditions and AGV characteristics. Such as charging priority, time priority, distance priority, variety priority, etc.
6. Change Paths and Settings
It can quickly change the running path and settings according to user requirements, including path and point coordinate movement, modification, addition and deletion, modification of definition content, etc.
7. Charge Control
7.1 AGV has intelligent control charging function. When the battery capacity of the car is consumed to a certain value, the request information will be sent automatically. The system will instantly schedule to a charging station for charging. And before completing the work task, follow the principle of task priority. If there is no free charging station, it will wait in line and the vehicle will not accept new tasks
7.2 The system updates the charging information in time through the signal, and can control the AGV to stop at the designated charging station, and trigger charging before the pull-in and isolation. After the charging is completed, the command trolley disconnects the isolation switch and starts working. The entire process is fully automated.
Outstanding Features of Laser-Guided AGV Systems
Using laser scanner positioning, high precision, generally ≤±5mm;
In terms of layout description, the computer support is higher;
Can communicate with the car continuously (radio or red);
With wireless feedback control performance;
Insensitive to interference (frequency influence, disconnection or loss of line, etc.);
The trolley controller adopts a building block structure, all parameters are defined by software, and it has powerful PLC support.
New installations on the basis of existing plant equipment can be carried out simultaneously with production;
The reorganization or expansion of equipment has little impact on shutdown and production;
Does not depend on the floor surface (sheet metal, rails, wood floors, etc.);
Has a more complex running route;
Except for the reflector, no other auxiliary positioning devices are used;
The running route can be changed quickly and easily.
No need to dig underground;
No need to invest in building high frequency power amplifiers;
The reflector has low cost, small size, limited quantity and easy installation.
1 The laser-guided AGV system gives full play to the advantages of laser technology, making the AGV walking process from the traditional segmented (usually several meters for a segment) blind walking after position correction to continuous (50ms/time) calculation, and the coordinate position is corrected in real time . Therefore, the positioning accuracy is high and the indicators are advanced.
2 The system has powerful functions, which can dynamically manage and monitor AGVs in real time. The front desk responds quickly and correctly, and the background data is detailed and accurate. It shows the careful consideration of the system in terms of management ideas, control methods, and field experience.
3 In the guide area, path modification, addition and deletion, re-planning, and definition can be quickly completed on the computer, so that users have no worries in adjusting production equipment, reorganizing production structure, technical transformation and updating.
4 The path planning flexibility of laser-guided AGVs is beyond the reach of traditional AGVs, and its advantages are more prominent for narrow passages, roadways, and criss-crossing driving paths.
5 The data management of the laser-guided AGV system is an important part of the basic information network of production logistics automation, which creates favorable conditions for the development of information automation management system in the future.