Though most think automated guided vehicles (AGV) are only used for moving work-in-process materials or finished goods along fixed guidepaths, there’s more than one way to use an AGV. It just takes a bit of creative thinking. Two companies in particular have found interesting ways to use this versatile material handling vehicle.
They’ve Got Mail
Although orders and other communications are predominately electronic, there’s still a need to distribute large amounts of paper throughout a facility. Plant managers at Greer, S.C.-based Creform Corp. were looking for a more efficient way to speed the flow of mail, parcels and paperwork throughout the building.
It turns out the solution was right under their noses. They realized the very product they were producing at the facility— the Creform Courier AGV—could be used to automatically deliver their own mail.
Employees used the Creform system of plastic-coated steel pipe, metal joints and hardware accessories to build and configure the right AGV for the application. Finishing touches on the AGV included a package tray on top for boxes and totes and large file drawers on the side marked with the names of various internal departments. Associates can clearly see tags indicating either “No mail” or “You’ve got mail.”
Managers wanted the vehicle to make six stops on its mail route: the tech center, inventory control, picking, assembly, shipping/receiving and packing. Once the stops and routes were identified, managers placed adhesive-backed magnetic tape on the floor, which is read by a magnetic induction sensor on the AGV’s drive unit. The routes can be modified at any time.
Today, the AGV courier travels approximately one-quarter of a mile, navigating its entire route twice an hour. It automatically controls exterior rollup doors via photocell and, as a safety measure, is equipped with an audible warning device, flashing light, E-stop buttons, non-contact object detector and safety bumper.
The AGV stops at each point for a pre-set period of time, but employees can press a stop button if they need more time.
Once they get their mail, employees can then send the vehicle on its way by pressing the start button.
The automated mail courier travels at speeds from 13 to 164 feet per minute and carries 620 pounds. Minimum turning radius is 24 inches, and two 12-volt, lead-acid batteries power the system. When it needs recharging, it is plugged into a 115-volt, 60-hertz, 15- amp outlet.
Now that Creform has discovered this new use for its own product, the company intends to export the application to other factories as well as distribution centers, medical labs, check processing centers, remittance processing areas and other locations that could benefit from automated mail delivery.
3D Load Sizing
Many material handling operations use sizing stations—metal structures equipped with a series of photoeyes or light curtains—to validate load parameters and ensure proper handling of materials by automated equipment. Sizing stations may also use weigh scales to validate the height, length, width and weight of loads.
Loads often fail because of improper pallet build, equipment maintenance issues or damaged material. When this occurs, the loads are routed to a reject area where manual intervention takes over. While sizing stations can validate load data for proper handling, they can’t identify the causes of regularly occurring failures.
To address this shortcoming, system integrator Nagle Research Inc. partnered with Sick USA, a supplier of high-tech sensing devices for material handling, to develop the Sentinel automated load inspection system. Sentinel uses 3D scanning technologies and sophisticated algorithms to determine the size of the load and its location relative to the pallet, the location of the pallet relative to the material handling equipment and the location of the AGV relative to the track centerline. It can also identify ghost-load conditions.
Operators first define acceptable dimensional boundary parameters and tolerances, and all loads are scanned and measured. The Sentinel system then displays a rotating 3D image on a computer monitor, and the data is stored for further review and parameter adjustment. If the load violates the specified boundaries, the software signals a PLC and provides information about the location of the violation. The load is then re-routed.
In March 2008, a large U.S. retailer started using the Sentinel system in its distribution center to prevent dropped and damaged loads due to offset pallets or overhanging boxes.
For this application, Nagle Research installed two LMS400 laser measurement systems (LMSs) on a gantry to verify the alignment and size of pallet loads. The Sentinel system gathers 3D data from the LMS sensors as the pallet passes through the frame. The sensors then feed the data into a computer, where software renders measurements for more than a dozen dimensions in less than a second. A PLC directs AGVs with non-conforming loads to a re-work station.
The retailer reports that the Sentinel system has helped to reduce downtime and product damage.