Vehicle manufacturer triples storage with automatic guided vehicles
When a vehicle manufacturer was assembling just one vehicle type in its facility, it had plenty of space for a FIFO (first-in, first-out) line-side parts storage system. But when the company considered expanding the assembly line from one vehicle type to three, it faced cramped floor space, extreme complexity in the assembler’s job, and increased travel distance between parts and the assembly task. The company found that a custom-engineered automatic guided vehicle (AGV) fleet could replace the line-side storage system with an automated parts sequencing operation for just-in-time parts retrieval.
Now, 19 customized and color-coded AGV carts deliver parts along paths marked by adhesive-backed magnetic tape. High-traffic areas use an embedded guide-path magnetic strip. Pieces of tape, aligned in specific patterns along the route, initiate various AGV functions such as turns, stops and speed changes.
The AGV drives operate on a 24-volt system with two 12-volt lead acid batteries, have a 1500-pound weight capacity, travel at a maximum speed of 82 fpm, and have a 24-inch turning radius. Safety equipment includes an audible warning device, flashing light, non-contact obstacle sensor, safety bumper and e-stops resulting in a safety category “B” rating.
The AGV carts have a deck for totes or boxes when required and hitches for towing trains of sequenced kitting carts. When necessary, the AGV carts have a convenient handle for manually moving them by raising the spring-loaded drive off the floor with a foot release pedal.
The batteries nest in battery boxes on a tray supported by rollers on the AGV cart, battery transfer cart, and battery charging station. The batteries are simply rolled off the AGV cart on to the battery transfer cart and then on to the charging station. Each vehicle has three sets of batteries for 24/7 operation.
In addition to increasing worker comfort and productivity, the new system ensures parts are always available for assembly and available space is used as efficiently as possible.
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