LEXINGTON, KY - Parts picked up from a central location are whisked to different assembly stations in the plant where they'll be installed in a car, flat screen TV or whatever widget is being built for the consumer marketplace. All this scurrying around to deliver parts to where they need to be is being accomplished today without humans but with smart, independent little machines.
An automated guided vehicle (AGV) is a machine that runs on a plant floor picking up, moving and delivering products from place to place entirely through computer programming and without an on-board human operator, making it a cost-effective solution for manufacturers. AGVs help reduce operating costs and increase efficiency, say developers, and several local plants use them. "It saves manpower. Your return on investment can be quick," said Tim Taylor, president of Industrial Concepts Inc, an 8-year-old Georgetown company that takes standard pallet trucks and "tuggers" (machines that haul parts around a plant) and converts them to self guided vehicles. Industrial Concepts recently held an open house to show potential customers how state-of-the-art AGVs provide parts delivery solutions and save money through automation.
The automated vehicles are run by computer programs using special software called automated vehicle intersection navigational utility or AVINU for short. The computer screen shows what looks like a city's traffic grid but in fact is the plant's layout with marked intersections and indicators where "traffic" (programmed AGV's) are at any given moment on the plant floor and what their assignments are. No human does the work, other than programming the computer to tell AGVs what to do during a given work shift or day. Vehicles can be wire, laser or magnetic guided.
Here's an example of what ICI does. The company takes a standard Toyota 10,000 load capacity "tugger" or material mover, normally operated by a human in an industrial plant, and converts it into an automated guided vehicle. The machine follows special magnetic strips embedded in the plant floor and adheres to a precise route throughout the plant picking up, hauling and delivering parts with no human interaction. "We do what we call a "kit conversion." Instead of building a whole custom AGV, we take a product already developed (for humans) and turn it into an AGV, so the cost is much lower," Taylor said. "Every part is off the shelf. The finished vehicle is also supported by the Toyota dealer network across the U.S. It is an AGV but it's also a manual vehicle so you can turn off the program, get on it and drive it around, if you need to."
The AGV performs its parts delivery chores in a variety of ways. It can report to a work station where a human is present and the worker will hand load material onto the AGV or the AGV will arrive at an unmanned work station and a gravity or power conveyer will automatically dump material into the AGV and it will go off to deliver it to another station. A third way is for a robot to load material onto the AGV and send it on its way. The system can be accurately programmed to the inch, so the AGV is in perfect position to receive or distribute material. A guided tugger can also pull "dollies," which are like attached flatcars on a train. You can pull as many as your turn radius can handle. For example, the AGV may be programmed to drop off dollies one through three in one location, four through seven in another.
Toyota builds various material delivery vehicles and ICI converts some of them for automated use. "The original purpose of AGVs was to use then at our facilities to increase manufacturing efficiency and reduce what we call muda (Japanese for waste)," said Tim Meyer, AGV Product Manager for Toyota Material Handling. "By reducing non-value added activity, we focus on value-added activities. Instead of manpower for material movement, employees can do welding, painting or quality inspections," Meyer added.
Toyota's newest assembly plant in Woodstock, Ontario builds the RAV-4 small SUV. The plant had the first launch of the Toyota "mouse" AGV, used for mass material delivery. "Instead of having a human drive the lugger, we have 150 automated 'mice' delivering rack after rack of parts to the line and taking empty racks back to a central material area to be reloaded," Meyer said. The Georgetown Toyota plant, opened in 1988, was not originally designed to use AVGs, but has now been retrofitted to use several AVGs.
The simplest vehicles start at around $10,000. More complex, higher load vehicles are $50,000 to $60,000, said Meyer. "The return on investment can be less than 12 months. The maximum amount of time for an ROI for any system we've installed was 24 months."
Is there any end to turning human work into machine work? Could robots build the automated guided vehicles themselves? "That's possible some day," Meyer said. "But don't forget, we still need humans to come up with programming and software."