An Automated Guided Vehicle (AGV) is an industrial material handling vehicle equipped with an automatic guidance system. It follows predefined routes or planned paths and performs tasks such as transporting, loading, unloading, and transferring materials without requiring a driver.
AGVs are generally equipped with navigation and positioning systems, travel drive units, control systems, and safety devices. Depending on the application, they can also incorporate automatic charging equipment, different types of load handling mechanisms, and communication interfaces for integration with production line equipment. Navigation methods, drive configurations, load capacities, and motion control systems vary between models and should be selected according to the actual operating environment.
1. Main performance characteristics and technical configurations of AGVs
1. Navigation methods
The navigation system determines the AGV's position and direction and provides the information required for path following and motion control. Common navigation methods include magnetic navigation, laser navigation, vision navigation, and QR code navigation.
Magnetic navigation
Magnetic navigation uses magnetic tape or magnetic markers installed on the floor to provide route references. Onboard magnetic sensors detect the magnetic field and send signals to the control system, which adjusts the vehicle's direction accordingly.
This method is established and relatively simple to install and maintain. It is suitable for warehouses and production lines where travel routes remain largely unchanged. However, the position of the magnetic tape or markers determines the vehicle's main travel path. When the production line layout changes, the floor markers usually need to be repositioned.
Laser navigation
Laser navigation uses an onboard laser scanner to collect information about the surrounding environment. The system matches the scan data with a previously created map or reference markers to determine the AGV's position and orientation.
Common methods include reflector-based laser navigation and natural feature navigation. The former identifies reflectors installed on walls, columns, or near equipment. The latter uses fixed environmental features such as walls and storage racks to locate the vehicle through laser scanning and map matching.
Laser navigation reduces dependence on fixed floor guidance infrastructure. It is suitable for facilities that require route changes or have complex material flow layouts. However, positioning performance depends on available environmental features, visibility, map quality, and changes to the facility layout.
Vision navigation
Vision navigation uses cameras to capture images of the surrounding environment. Image recognition, feature extraction, and image matching techniques are then used to determine the vehicle's position.
Depending on the system design, navigation may rely on floor markings, environmental features, or predefined visual patterns. Vision navigation can reduce dependence on fixed floor guidance infrastructure, but its performance may be affected by changes in lighting, reflections, obstructions, and image quality.
QR code navigation
QR code navigation uses QR code markers installed on the floor. A camera or dedicated recognition device mounted on the AGV reads the codes and obtains the corresponding position and direction references.
This method provides clearly defined positioning references. The markers are relatively easy to install, and routes can be adjusted when necessary. It is suitable for indoor logistics environments with relatively fixed routes that still require some flexibility.
QR codes can be affected by wear, dust, and contamination. The floor markers therefore require regular inspection to maintain readability and positioning accuracy.
Each navigation method has different requirements in terms of infrastructure investment, positioning conditions, maintenance, and route modification. No single method is suitable for every facility. Selection should be based on the factory layout, floor conditions, material flow routes, and automation requirements.
2. Drive systems
The drive system provides the power required for AGV movement. Different wheel arrangements and control methods are used to achieve forward travel, reverse travel, and turning. Common configurations include single-steering-wheel drive, dual-steering-wheel drive, and two-wheel differential drive.
Single-steering-wheel drive
A single-steering-wheel system generally uses one integrated steering drive wheel together with two or more passive support wheels.
The drive motor controls wheel speed, while the steering motor adjusts the wheel orientation. This arrangement has a relatively simple drive layout and is suitable for indoor logistics equipment with defined travel routes and no special requirement for lateral movement.
Its turning capability depends on the steering wheel mounting position, steering angle, and vehicle dimensions. The actual turning space must be considered during vehicle selection and route planning.
Dual-steering-wheel drive
A dual-steering-wheel system uses two independently controlled steering drive units to provide traction and steering. The control system coordinates the steering angles and travel speeds of both wheels to move the vehicle along the required path.
Compared with a single-steering-wheel arrangement, dual-steering-wheel drive offers more combinations of steering and motion control. Different movement patterns can be achieved depending on the wheel layout.
This configuration is suitable for equipment requiring greater maneuverability and more flexible steering control. However, it requires more coordination between the steering angles and speeds of both wheels, placing higher demands on the control system and mechanical design.
Two-wheel differential drive
A two-wheel differential drive system generally consists of two independently driven wheels on the left and right sides, together with one or more passive support wheels. By controlling the speed and rotation direction of each drive wheel separately, the AGV can move forward, backward, turn along a curved path, or rotate in place.
This arrangement does not require a separate mechanical steering mechanism. Its chassis layout is relatively simple, and its control principle is well established. It is suitable for AGVs that need to change direction within limited spaces.
Movement accuracy depends on speed coordination between the two drive wheels, tread wear, floor friction, and encoder feedback. A standard two-wheel differential drive configuration cannot move directly sideways.
3. Battery and charging methods
The battery supplies power to the AGV's drive motors, controllers, navigation equipment, and other onboard devices. Battery capacity and charging methods should be selected according to operating shifts, equipment utilization, and production schedules.
Automatic docking and charging
Automatic docking and charging systems use a fixed charging station that connects to the AGV through an onboard charging interface. When the battery reaches a predefined condition, the control system sends the vehicle to the charging location, where automatic positioning and docking establish the charging connection.
This method reduces manual connection and disconnection of charging cables. It is suitable for logistics systems that require continuous or multi-shift operation.
Opportunity charging
Opportunity charging allows the AGV to recharge during short periods when it is waiting for tasks, paused between transport operations, or completing loading and unloading activities.
The control system uses battery status and task schedules to determine when the vehicle should move to a charging station. This approach can reduce downtime in material handling operations. However, the charging strategy must be matched to the battery type and available charging power.
Scheduled charging
Scheduled charging follows a predefined operating plan. For example, AGVs can be assigned charging periods during shift changes, breaks, or other non-production intervals.
This method simplifies charging management and is suitable for facilities with regular operating shifts and predictable task schedules.
Battery replacement
When the battery charge becomes insufficient, the depleted battery can be replaced manually or through an automated battery changing system. The AGV can then return to operation with a charged battery.
This method is suitable for applications that require high equipment availability and extended operating time. However, it requires spare batteries and appropriate charging and battery management facilities. Battery replacement procedures and storage conditions must also be considered.
4. Communication methods
The communication system exchanges data between AGVs, central fleet control systems, host computers, charging equipment, and other production devices. Wired or wireless communication can be used depending on the system layout and interface requirements.
Wired communication
Wired communication uses industrial Ethernet or other physical interfaces to connect fixed equipment. It provides a stable communication link and allows the transmission conditions to be managed more directly.
This method is commonly used for data exchange between charging stations, production line equipment, fixed control cabinets, and supervisory control systems.
For mobile equipment, cable drag chains, connectors, and movement range must be considered. Conventional fixed wiring is therefore not normally used as the primary communication method while an AGV is moving.
Wireless local area network communication
Wi-Fi is a common wireless communication method in AGV systems. Vehicles connect to the factory network through wireless access points to receive task information and report operating status.
Wireless communication eliminates the need to install communication cables along AGV travel routes. It is suitable for warehouses and production facilities with multiple operating areas and fleets of mobile equipment.
Communication stability depends on wireless coverage, signal interference, network roaming, and device configuration. Wireless access points and network coverage should be planned according to the vehicle operating areas.
Bluetooth communication
Bluetooth is generally used for short-range device connections, parameter configuration, equipment commissioning, and maintenance. Its operating range and communication distance are relatively limited, so it is not normally used as the primary communication method for large AGV fleets.
Infrared communication
Infrared communication transmits data through infrared light signals. The transmitter and receiver generally need to maintain suitable alignment and an unobstructed optical path.
It can be used for short-range communication between specific devices, but its operation is limited by obstructions, installation angles, and transmission distance. Its use in modern AGV systems is relatively limited.
Wireless local area networking is one category of wireless communication, rather than a separate technology at the same level. The communication method should be selected according to transmission distance, vehicle mobility, data requirements, and reliability.
5. Control systems
AGV control generally involves cooperation between onboard controllers and a central fleet control system.
The onboard controller processes navigation and positioning information, travel speed commands, steering angles, motor drive signals, and sensor data. It controls the vehicle so that the AGV can carry out its assigned movement and handling tasks.
The central fleet control system manages tasks across multiple AGVs. Its functions include task allocation, path planning, traffic coordination, vehicle status monitoring, and charging management.
In systems where multiple AGVs operate together, the fleet control system must also handle path conflicts and shared resource allocation. This helps prevent multiple vehicles from entering the same narrow aisle or equipment operating area at the same time.
Different brands and models of mobile robots can use standardized communication interfaces to exchange data with a central fleet control system. For example, VDA 5050 defines an interface for communication between mobile robots and a central fleet control system, supporting the exchange of job and status information in intralogistics applications.
6. Safety protection measures
The AGV safety system should be designed according to the operating environment, vehicle structure, load conditions, and areas where personnel may be present. Common components include safety sensors, emergency stop devices, warning devices, and safety control functions.
Non-contact safety protection
Common devices include safety laser scanners and other non-contact protective equipment that meets the required safety performance specifications.
A safety laser scanner can establish protective fields around an AGV. When a person or obstacle enters a defined area, the system can reduce the vehicle speed or initiate a protective stop according to the configured safety logic.
Unlike ordinary obstacle detection sensors, safety-rated devices must meet applicable safety performance requirements and work with the safety control system.
Contact safety devices
Contact safety devices generally include safety bumpers and pressure-sensitive edges. When the AGV makes contact with an obstacle, these devices send a signal to the safety control system, triggering the configured stopping function.
They are commonly used as supplementary protection alongside non-contact safety devices. The actual configuration should be determined according to the vehicle dimensions and risk assessment.
Emergency stop devices
Emergency stop switches provide a means of requesting a stop when an unsafe condition occurs. They send a command to the safety control system, which initiates the appropriate emergency stop function.
Emergency stop devices should be installed in accessible positions. Their arrangement must also account for the vehicle's stopping distance and braking capability.
Audible and visual warning devices
AGVs commonly use warning lights and buzzers to indicate vehicle movement, turning, startup, and abnormal operating conditions. These signals alert personnel working near the vehicle.
The safety control system should also monitor conditions such as communication loss, navigation faults, drive system failures, and brake status. Depending on the applicable safety logic, the vehicle may reduce its speed or stop when an abnormal condition is detected.
Safety equipment should not be selected solely by listing sensor types. The complete vehicle requires a risk assessment and verification against applicable safety standards. ISO 3691-4 is one of the relevant standards for the safety design of driverless industrial trucks.
2. Main structural components of an AGV
The mechanical and electrical structure of an AGV generally consists of an automatic guidance and positioning system, drive unit, load handling mechanism, safety protection devices, control system, and power supply system. The actual configuration depends on the vehicle type and material handling requirements.
1. Automatic guidance and positioning system
The guidance system collects information about the surrounding environment and the AGV's own position. This information is used for path following and motion control.
Depending on the navigation method, the system may include magnetic sensors, laser scanners, cameras, QR code readers, and inertial measurement units.
For example, a magnetic navigation AGV requires magnetic sensors, while a QR code navigation AGV uses a camera or dedicated recognition device. A laser navigation system generally matches laser scan data with reflectors or an environmental map.
The collected information is sent to the onboard controller to determine the vehicle's position and travel direction.
2. Travel drive unit
The drive unit provides the power required for AGV movement. It generally includes drive motors, gearboxes, drive wheels, support wheels, and associated transmission components.
Different drive configurations require different mechanical arrangements. A single-steering-wheel system uses an integrated traction and steering assembly. A dual-steering-wheel system coordinates multiple steering drive units, while a differential drive system uses the speed difference between the left and right drive wheels to control turning.
Drive unit selection should account for vehicle weight, maximum payload, travel speed, acceleration requirements, and floor conditions. The output torque, load capacity, and transmission efficiency must meet the vehicle's operating requirements.
3. Load handling mechanism
The load handling mechanism allows the AGV to load, unload, and transfer materials. It connects the vehicle with production equipment and logistics systems.
Common designs include:
Roller conveyor transfer: Powered or gravity rollers move materials between the AGV, pallets, containers, and conveyor lines.
Belt conveyor transfer: A conveyor belt transports materials and is suitable for applications requiring continuous or controlled material transfer.
Fork-type handling mechanism: Forks and a lifting mechanism pick up and transport pallets or other load carriers.
Lift-top transfer mechanism: A lifting device raises a load or carrier platform to establish a transfer connection with racks, conveyor lines, or other equipment.
Robot arm handling mechanism: A robot arm and its associated actuators are integrated into applications requiring specific gripping, handling, or assembly operations.
The appropriate mechanism depends on the dimensions and weight of the cargo, its bottom structure, and the design of the equipment receiving the load.
4. Safety protection devices
Safety protection devices detect personnel, obstacles, and abnormal equipment conditions in the operating environment. Their purpose is to reduce collision risks and other hazards during AGV operation.
Main components include safety laser scanners, contact bumpers, emergency stop switches, audible and visual warning devices, and associated safety control components.
The detection areas and safety functions vary between vehicle models. For applications involving heavy loads, higher travel speeds, or frequent interaction with personnel, the protective fields and stopping strategies should be designed according to the risk assessment.
5. Control system
The control system coordinates the AGV's navigation, travel, steering, load handling, and safety functions. It generally includes an onboard controller, motor drives, sensor interfaces, communication modules, and control units for the actuators.
The onboard controller uses positioning information from the navigation system and task commands from the host computer to control the drive motors and associated mechanisms. This allows the AGV to move and carry out material handling operations.
In multi-vehicle systems, the control system communicates with the central fleet management platform. It receives transport tasks and reports vehicle position, battery status, equipment faults, and task progress.
6. Power supply and charging system
The power supply system generally includes the onboard battery, battery management system (BMS), power distribution unit, and charging interface.
The battery supplies power to the AGV's drive system, control equipment, navigation devices, and load handling mechanisms. The BMS monitors battery voltage, temperature, state of charge, and other operating conditions. It works with the vehicle control system to manage power consumption and battery operation.
Depending on the operating schedule, the vehicle may use manual charging, automatic docking and charging, or a battery replacement system. Battery capacity and charging methods should be selected according to operating time, task frequency, and available charging intervals.
3. Custom machining requirements for AGV components
In addition to electrical controls and navigation equipment, AGVs contain many mechanical transmission and structural components. These include drive unit mounting bases, wheel hubs, connecting shafts, bearing housings, load handling support plates, sheet metal enclosures, and equipment mounting brackets. Their dimensions must match the vehicle structure and available installation space.
For non-standard AGVs, some structural components cannot be selected directly from standard product catalogs. They need to be manufactured according to customer-supplied engineering drawings.
Hansheng Automation provides CNC precision machining and metal component manufacturing according to customer drawings. In addition to parts for AGVs and logistics automation equipment, our machining services cover precision yacht components, RC racing car structural parts, tobacco packaging machinery components, and filling machinery parts. Each component is manufactured according to the specified dimensions, materials, and assembly requirements.
