Automated Guided Vehicles

Featured AGV Technologies

How Automated Guided Vehicle (AGV) Technology Works

Typically, AGVs employ one of two methods for guidance. The first and oldest method consists of a fixed path such as wire, tape, or paint on the facility floor. The AGV senses the location of the path and follows it subject to the instructions of a central traffic controller. Commands from the traffic controller are usually sent as a radio message to the vehicle. In some cases, Infra-red communication access points are used for this, and some technologies actually broadcast the signal over the wire.

Owing to the difficulty in installing, maintaining and changing the physical path based design, free-ranging AGV guidance technology is now the most popular method of control. This method uses either inertial navigation technology combined with an odometer to control direction speed and positioning, or the more common method is to use a system of Mirrors and Lasers that are continuously triangulating the vehicles position.

Another “semi-pathless” method of guidance is provided by strategically embedding magnets in the path to be followed – and combining the ability to move from magnet to magnet with the odometry technology mentioned earlier. All of these latter methods are attempting to address the problem of moving wires or physical paths to make a change. This can be a problem in an installation where ongoing operations would possibly be affected by the disruption of the change.

One of the benefits of this so called “autonomous” guidance system is that the vehicle can now make decisions about how to route itself based on real time feedback of traffic and obstruction information. The primary benefit of this approach, however, is the ease with which a path can be established and then changed as requirements in the process evolve. Most systems use a CAD based program to define the available paths throughout the process, along with the points at which the AGV can pick up or deposit a load. Then, an AGV is physically driven through the plant on a human operated pendant, where it learns the location of all mirrors. Finally, the information from this exercise is uploaded to the CAD system. All paths, and changes to the paths are designed at the CAD station, and downloaded to the AGV’s in the process. The traffic controller is then responsible for requesting load movements, and assigning vehicles to the task. Each vehicle can then autonomous determine the most efficient path through the process to complete its mission.

AGV System Benefits Include:

• Reduce variances found in human delivery operations
• Lower lifetime cost of non value added transportation of materials
• Ability to transport materials without adding barriers, such as conveyors, into your system

Applications that maximize the benefits of AGV's

AGV System Features

• High-Efficiency Permanent batteries – no routine battery changing is required. While there are some recommended charging maintenance procedures to insure that a ten year operating life on the battery is achieved, most are automatically performed by the system during non-work periods. This ultimately means no battery changing, no special operators for changing or charging batteries, no degassing facility, and no need to handle hazardous fuel for disposal.
• These AGVs often employ automatic opportunity battery charging stations throughout the path so vehicles need not be removed from service. Each time the vehicle interfaces a drop off position, opportunity charge connectors can be used to “give the vehicle a drink” before it moves to the next task. In some cases, a special area is setup for the vehicles to use when parking that can also serve as charging positions. In most cases, a 2 minute charge will provide 20-30 minutes of capacity.
• Easy and fast installation – Aside from making sure the path is defined in the CAD programs used to manage the process, and placing the charging receptacles in convenient locations, Bastian offers AGVs which need no additional wiring.
• A flexible layout – While Bastian offers vehicles that use a physical path, laser guided vehicles are typically used if there is the possibility of needing to make path changes at some point in the future. These systems are modified using a CAD based interface to the guidance program. Typically no physical changes to the process are made aside from the placement or relocation of load pickup and delivery points. This capability would, for example, allow the user to disable a specific pathway if needed because of some special construction that may take place in that area. The change would be designed on the CAD station, broadcast to all vehicles, and completed with no direct, “on floor” intervention on the part of the user.
• Better space utilization – Most of the AGV products Bastian offers have multi-directional movement including forward, backward, and sideways (90 degrees). Since the vehicles can literally turn on a dime, the large corner radii needed for forklifts or other transport medium is eliminated.
• Easy support and service – through the use of an onboard smart controller. This controller continuously updates and records the vehicle’s operational status thus displaying the probably cause of any issue that might occur. The Maintenance Operating Systems offered by Bastian also assist with the automated tracking of usage, and the scheduling of PM service routines per the manufacturer’s recommendations – relieving the shop staff of the need to monitor and schedule these procedures.
• Safety – through the use of ultrasonic sensors in addition to acoustic and visual indicators, emergency stop buttons, contact bumpers surrounding the perimeter of the vehicle thus providing optimum safety in your environment.
• Two stage obstacle sensors – indicates to the AGV to slow down (stage 1) or stop(stage 2).
• Visual operating indicators – display the direction of travel.
• Emergency stop buttons – on all four sides of the AGV for safety.
• Return on Investment – These vehicles are routinely applied in 24/7 operations where they don’t take vacations, call in sick, ask for raises or benefits, or leave and require a replacement that will go through a learning curve. These any many other savings quickly provide a superior return on investment over more conventional – manual alternatives.

Bastian offers a wide range of AGV options and will take your specific application and requirements into consideration when determining the best AGV system to meet your needs.

Industries Where AGV's Are Used