Automatic Guided Vehicles | What are the Different Types?

What are Automatic Guided Vehicles?

Automatic guided vehicles (or AGVs) are load carriers that are wheel-based and controlled by a computer, so it can travel along a surface without an operator or driver on board. The movement of automatic guided vehicles is controlled by both sensor and software-based systems. AGVs are equipped with an automatic obstacle detection bumper which ensures the safe and nonproblematic transfer of loads.

Benefits of automatic guided vehicles include flexibility, accountability, repeatability, safety, reduced operating cost, and scalability. When a situation such as a need for change in handling or production, the AGV can be easily adjusted to accommodate this need. The whereabouts and designated locations and destinations of AGVs are also tracked, so cases of misplaced products or goods are easily prevented. They are programmed to stop when they suddenly encounter an obstacle or obstruction once these vehicles start with their designated path. In addition to these, AGVs can execute tasks that involve repetitive movements with accurate and precise motions.

What are their Applications?

Applications of automatic guided vehicles include the transportation of raw materials as well as finished goods to be transferred to manufacturing lines, storage warehouses, and/ or warehousing and distribution applications.

automatic guided vehicles applications

AGVs are able to collect parts for assemblies, move products through production processes, docks, or storages, transfer loads to aisles, and tow trailers of materials to consumption points.

Navigation and Guidance of AGV Systems

Automatic guided vehicles guide and navigate through one of three main methods.

In wire guidance, the vehicle makes use of a sensor under the vehicle in order to detect the RF signal from a wire placed in a lot that is approximately an inch below the floor surface.

In laser target triangulation, reflective targets are placed above the floor on columns, walls, or posts that are about 25 feet apart. Each of the facility targets is surveyed and is given a distinct X,Y coordinate which is loaded into the memory of the AGV. On each vehicle there is a rotating laser light beam source as well as a receiver. When this laser light reflects off a facility target, the distance and angle are quickly and automatically measured. Through this, the AGV can easily calculate its position, comparing its calculated position to a coordinate map of the path stored in its memory. This then determines the vehicle’s steering instructions as it maneuvers throughout the facility.

Inertial or gyro navigation is another form of non-wire guidance and navigation for AGV systems. This device is able to detect very small deviations in the direction of travel of the vehicle. Similar to laser navigation, the path of the vehicle is a set of coordinates stored in its memory. Small magnet markers are installed in the floor surface approximately every 25 feet along the AGV’s path. These markers serve as reference points to correct any small error that is accumulated over the distance between markers.

What are the Different Types of Automated Guided Vehicles?

Types of AGVs include unit load AGVs, tugger AGVs, automated forklift AGVs, and automated carts. These types will be further discussed in separate articles that will follow.

Automated Carts

Automated Carts AGV

These are the simplest kind of automatic guided vehicles. Also known as automated guided carts (AGCs), they have minimal and basic features which make this type having the lowest cost among all the others. They are guided by flexible magnetic tape that is adhered to the floor surface. These magnetic strips can be moved into the floor around heavy traffic areas.

Unit Load AGVs

Unit Load AGVs

Unit load AGVs transport loads such as bins, carts, or pallets either on forks or on the deck of the AGV. They are equipped with decks that permit unit load transportation and automatic load transfer. These decks can by a lift and lower type, have powered or non-powered rollers, or chain or belt decks.

Tugger AGVs

Tugger AGV

Also known as towing vehicles, this type of automatic guided vehicle consists of powered units that pull a series of nonmotorized trailers, each of which carries a load. They were the first type introduced and are still a popular type until today. These AGVs have load capacities that range from 2000 to 160000 pounds.

Sources:

http://www.mhi.org/fundamentals/automatic-guided-vehicles

http://www.mhi.org/casestudies?q=&sort=&page=1&fq=cat-product:Automatic+Guided+Vehicle+Systems

AGVs