AGV (Automated Guided Vehicles) is also known as unmanned carrier, automatic navigation vehicle and laser navigation vehicle. It refers to a transport vehicle equipped with automatic navigation devices such as electromagnetic or optical devices, capable of driving along the specified navigation path, and having safety protection and various transfer functions.
In industrial applications, the mobile vehicle does not need a driver, and its power source is a rechargeable battery. Generally, computer can be used to control its travel path and behavior, or electromagnetic path following system can be used to set its travel path. The electromagnetic track is stuck on the floor, and the unmanned carrier moves and acts based on the information brought by the electromagnetic track.
Characteristics of AGV
The outstanding feature of AGV is unmanned driving. AGV is equipped with automatic guidance system, which can ensure that the system can automatically drive along the predetermined route without manual pilotage, and automatically transport goods or materials from the starting point to the destination. Another feature of AGV is its good flexibility, high degree of automation and high level of intelligence. The driving path of AGV can be flexibly changed according to changes in storage location requirements and production process flow, and the cost of changing the running path is very low compared with traditional conveyor belts and rigid conveyor lines. AGV is generally equipped with a loading and unloading mechanism, which can automatically interface with other logistics equipment to realize the automation of the whole process of cargo and material loading and unloading and handling. In addition, AGV also has the characteristics of cleaner production. AGV relies on its own battery to provide power, which is noise free and pollution-free during operation, and can be used in many places that require a clean working environment.
Classification of AGV
1. Electromagnetic induction guided AGV
Electromagnetic induction guidance is generally to bury wires on the ground along the preset driving path. When high-frequency current flows through the wire, electromagnetic fields will be generated around the wire. Two electromagnetic inductors are symmetrically installed on the AGV from left to right. The difference in the strength of the electromagnetic signals they receive can reflect the extent to which the AGV deviates from the path. The automatic control system of AGV controls the vehicle steering according to this deviation, and continuous dynamic closed-loop control can ensure the stable and automatic tracking of AGV to the set path. This electromagnetic induction guided navigation method is used in most commercial AGVs, especially for large and medium-sized AGVs.
2. Laser guided AGV
The AGV is equipped with a rotatable laser scanner, and a laser positioning sign with a highly reflective reflective plate is installed on the wall or pillar along the running path. The AGV relies on the laser scanner to emit the laser beam, and then receives the laser beam reflected from the surrounding positioning signs. The on-board computer calculates the current position of the vehicle and the direction of movement, and corrects the orientation by comparing with the built-in digital map, So as to realize automatic handling.
The application of this kind of AGV is more and more common. And according to the same guiding principle, if the laser scanner is replaced with an infrared transmitter or an ultrasonic transmitter, the laser guided AGV can be changed into an infrared guided AGV and an ultrasonic guided AGV.
3. Vision guided AGV
The vision guided AGV is a rapidly developing and mature AGV, which is equipped with CCD cameras and sensors, and the on-board computer is equipped with the image database of the environment around the AGV path. During AGV driving, the camera dynamically acquires the image information of the surrounding environment of the vehicle and compares it with the image database to determine the current position and make decisions on the next step of driving.
This AGV does not require any physical path to be set manually, so it has the best guidance flexibility in theory. With the rapid development of computer image acquisition, storage and processing technology, this AGV is more and more practical.
In addition, there are many forms of AGV, such as ferromagnetic gyro inertial guided AGV and optical guided AGV.