Automated Guided Vehicles(AGV)

What is AGV?• Automated Guided Vehicles (AGVs) are driverless

industrial trucks, usually powered by electric motors and batteries.

The Automatic Guided Vehicle (AGV) is a safe, reliable, and efficient material transport system that can be used instead of forklifts to move loads of all sizes.

AGVs are available in tape, wire, and laser guidance configurations for maximum layout flexibility, and their crabbing capability saves floor space.

AGV models are available to transport weights from 220 to 550 lbs., as well as pallets up to 6,600 lbs.

Automated Guided Vehicles (or Automatic Guided Vehicles) have been moving materials and products over 50 years.

The first AGV system, a modified towing tractor with trailer following an overhead wire, was built and introduced in 1953 in a grocery warehouse.

• By the late 50's and early 60's towing AGVs were in operation in many types of factories and warehouses. This type of AGV, a tugger, is still applied today.

Components of AGV

•Vehicle.

•Guidance system.

•Input/output/transfer mechanism.

Classification criteria of AGVs

Tote/box or pallet handling. Guidance system

Tape. Wire. Laser.

Input/output/transfer mechanism Roller conveyor. Chain conveyor. Fork top. Rear fork.

Battery charge/recharge option. Number of vehicles.

Technological features of AGV▫ Permanent 10-year battery eliminates need for battery

changing.

▫ Opportunity charging allows automatic battery charging without removing vehicle from service.

▫ Quiet operation (<65 db).

▫ Multi-directional wheels allow travel forward, backward and sideways, with 90º crabbing, minimizing space requirements.

▫ Microprocessor control with Radio Frequency (RF) communications.

▫ Laser guidance option allows maximum layout flexibility.

History Of AGV:-•First AGV developed in 1954 by A.M.Barrett,Jr.•Using a overhead wire to guide a modified

towing truck pulling a trailer in a grocery warehouse.

•Subsequently, commercial AGV were introduced by Barrett.

•1973, Volvo developed automated guided vehicles to serve assembly platforms for moving car bodies through its final assembly plants.

•Later, Volvo marketed their unit load AGVs to other car companies.

Navigation system of AGVs• The first generation navigation schemes were expensive to

install. The exact path of the AGV needed to be 'cut' in the floor to bury the wire in. The cut for a turn had to follow the radius curve that the vehicle would make when turning. Many systems had to embed four wires - three for guidance and one for communications. Often, rebar or electronic signals would interfere with the guidance signals imposed on the wires.

• Today the wire-guided technology is outdated. New AGV guidance systems, such as the FROG-technology, offer many advantages (installation costs, flexibility, maintainability) over the wire-guided AGV technology.

As electronics and microprocessors advanced, so did AGV applications. More intelligent Automatic Guided Vehicles were created and the need for a sophisticated path was reduced.

The first major development was 'dead reckoning'. Dead reckoning is the ability to traverse space without having to rely on the physical presence of a guidance wire. The biggest advantage was that dead reckoning eliminated the need to make the cut radius turns at intersections. The AGVs could leave the wire, turn at a programmed radius, and then pick-up the wire to continue its course of travel. The path still required multiple wires in the floor, but the installation was greatly simplified.

• During the 1980s, non-wire guided AGV systems were introduced. Laser and inertia guidance are two AGV guidance technologies allowing for increased system flexibility and accuracy. Changes to the path can be made without costly, time-consuming floor alterations or production interruptions.

• Modern AGVs are computer-controlled vehicles with onboard microprocessors (such as the FrogBox and FrogBox Light). Most AGV-systems also have a supervisory control system (e.g. SuperFROG) to optimise the AGV utilization, generate and/or distribute transport orders, tracking and tracing

modules and acting as 'traffic cop' based on priorities.

IM70 It is a wireless communication device

used for the intercommunication between a driverless carrier (AWG) and the central control system.

When the AWG gets an order to pick up an article from the store.

It needs to navigate its way along a wire sling which is buried in the concrete floor.

IM70 is a little box under the vehicle capable of using this wire sling as a bi-directional data link. All digital electronics was built around a Xilinx. FPGA.

An inductive modem for wireless guidance of AGV

Software related to AGVs• AGV Manager is the name of a software which is basically

dealing with the flow management.

• This is based on a modular core which allows it not only to manage AGVs fleet but also operators, palletisation cells,  stretch-wrapping or pallet covering machines, automatic or manual warehousing, dispatching.

Its flexibility allows it to easily integrate with any industrial process — production and logistics — and to communicate with all management systems (ERP, WMS, GPAO, etc). 

With its Focus functionalities, it can manage a simple automatic point-to-point transfer,  ends of lines, storing missions, or a whole warehouse. 

Traceability and Adaptation by AGV

• AGV Manager also integrates the identification and traceability of all loads transported. 

• It provides a complete tracking of the products, from production to dispatching and warehousing.

• Whether installations are existing or not, manual or automatic, computerized or not, AGV Manager adapts to all your constraints in order to manage your production logistics and meet all your needs.

Benefits of AGV

▫Eliminates forklift traffic.

▫Individual load tracking from pickup to delivery for precise inventory control.

▫Safe, reliable operation using ultrasonic sensors, acoustical and visual operating indicators, emergency stop button, and full-perimeter contact bumper.

Applications• Within industrial environments, the use of AGVs has evolved

drastically: from traditional distribution-oriented applications at one end of the spectrum to complex computer-controlled automobile assembly systems with robotic interfaces at the other end.

• They can be stand-alone systems, an integral part of another system, or aid in pulling together islands of automation.

• AGV originally designed for horizontal transportation of palletized material, the design and application of AGVs and controls are now as varied as those of industrial robots.

• Outside industrial environments, Automated Guided Vehicles are now also being applied for transhipment at ports, as people movers and in the entertainment industry.

Replacement Applications of AGV

▫Conveyors

▫Forklift trucks.

▫Hand carts.

Applications of AGV in Automobile Applications of AGV in Automobile IndustryIndustry• Typical AGV applications in the automotive industry

include automated raw material delivery, automated work in process movements between manufacturing cells, and finished goods transport.

•  AGVs link shipping/receiving, warehousing, and production with just-in-time part deliveries that minimize line side storage requirements. 

• AGV systems help to create the fork-free manufacturing environment which many plants in the automotive industry

are seeking. •

Advances of AGVS over previous technology

▫Reduced load damage. ▫Less facility wear and tear. ▫Requires less operating space. ▫System capacity increased by adding

vehicles. ▫Elimination of single-point failure;

system can continue operating if a vehicle fails.

Problems addressed by AGV

Floor space ▫Provides more space for production.

•Productivity ▫Supplements limited capacity in storage

and production areas. •Inventory

▫Solves the problem of poor product accessibility

Problems addressed by AGV

Ergonomics ▫Workers in hostile environments. ▫Workers walking long distances▫Excessive noise levels from material

handling equipment ▫Safety hazards▫Labor-intensive processes

Problems addressed by AGV

Disjointed Operations (Lack of Integration)▫Multiple staging areas ▫Product is often moved from one staging

area to another•Labor

▫High employee turnover▫High labor costs▫Small labor pool▫Low job satisfaction

Exemplary specifications of AGV• Maximum load weight: 220-

6,600 lbs. (100-3000 kg).

• Maximum load size:Length: 30-51 in. (0.76-1.30 m).Width: 20-47 in. (0.50-1.19 m).

• Maximum speed: 164-196 ft./min. (50-60 m/min.).

• Crabbing speed: 49 ft./min. (15 m/min.).

• Turning radius: 24-56 in. (.60-1.42 m).

Transfer height: 16-21 in. (.41-.53 m).

Traveling direction: multi-directional.

Battery voltage: 48 V. Battery capacity: 40-80

Amp. hrs. Battery

charging/discharging ratio: 1:10.

Communication: spread spectrum radio frequency.

Steering system: direct drive power wheel steering.

Photographic view of a forklift type AGV with wireless

guiding system

AGV accessing materials from different AGV accessing materials from different racksracks