Each of those operators, he estimates, would earn about $7.50 an hour; with benefits included, they'd wind up costing more than $10 an hour. A Unimate 2000 -- even when all costs of acquiring and operating it are factored in -- works for less than $6 an hour, which comes to an annual savings of $156,000 -- $216,000 in operator costs alone. When reductions in scrap and maintenance are added in, the savings mount even higher. And a Unimate never quits or dies. The units can be rebuilt by the manufacturer virtually ad infinitum.
"You can also run more hours per day on a consistent basis with a Unimate than you can with manual operation," says McClurken. "Since we're really selling a manufacturing service -- our talent and the time on our machines -- hours of operations is crucial."
McClurken estimates that the robots trim his breakeven point by about $150,000. With larger orders (short runs don't justify the use of a Unimate) or improved plant layout, the figure could be more significant. "They're capable of greater utilization than we've been able to attain so far," he says. As far as McClurken is concerned, the more "Knuckleheads" there are in the world, the better.
Webster's New Collegiate Dictionary offers a more precise description of a robot than a "Knucklehead." It defines a robot as "a machine that looks like a human being and performs various complex acts (as walking or talking) of a human being" -- like R2D2 or C3P0 or some similar Star Wars contraption. But the Robot Institute of America, the Dearborn, Mich.-based trade association for robot manufacturers, distributors, and users, defines the robot much more narrowly: It is, according to the institute, "a reprogrammable multifunctional manipulator designed to move material, parts, tools, or specialized devices, through variable programmed motions to accomplish a variety of tasks." Rather than cute chrome-plated midgets, the most common units are simply elaborate mechanical arms. Fitted with "fingers" -- everything from grippers to wrenches to spray guns to arc-welding equipment -- and programmed either by mechanical means or by a computer, the arm becomes a robot.
And what does the industrial robot do? Quite simply, it moves something from one point to another.
But it does so with amazing accuracy and dependability.
Today's robots are used principally for spot welding, spray painting, die casting, investment casting (making molds in sand), loading and unloading machine tools, stacking items on pallets, and plastic molding. They're also used in foundry, press, metal deburring, and brick and glass handling work. Experts predict robots will have a major impact on arc-welding and assembly operations; their use in the latter application is expected to quadruple by 1990.
In a factory, robots may position a spot-welding unit on the seams of an automobile's shell, float a spray gun across a refrigerator, or pack bottles of cologne in gift-wrapped containers.
In a Chesebrough-Pond's plant in Huntsville, Ala., a Puma 500 robot outfitted with a miniature squirt gun sprays liquid cosmetics, such as eye shadow and cheek blush, into tiny metal pans that will be inserted into Prince Matchabelli compacts. At another of the company's plants, one in Clinton, Conn., a robot places glass bottles onto an assembly line where they will be filled with one of the components of Rave home permanent; the robot plunks down 8 jars at a time, about 130 jars each minute.
Robots handle plutonium for the U.S. Department of Energy, make light-bulb filaments for Westinghouse, drill parts for the F-16 fighter for General Dynamics, assemble motorcycle engines for Yamaha, and, at one robot factory in Japan, manufacture more robots. Futurists envision robots mining the deep-seabed, serving drinks to partying executives, and waging war in place of the common foot soldier.
For now, however, they've been relegated to simpler moving tasks. Speed, accuracy, payload size, the type of power they use, and memory capacity are among the criteria that determine how well suited a robot is for a given task. Robots are also rated by axes of motion (essentially the number of directions in which the arm and its "fingers" can move -- three to six is standard), repeatability (how accurately it will return to a given point in space during normal operation), and velocity. A Unimate 760, for instance, can maneuver a 22-1b. load in six directions at a speed of 1,000 mm/sec., bringing it to within.008 inches of a predetermined point, over and over again.
Robots may be driven pneumatically, hydraulically, or electrically, and are programmed either by mechanical means, such as a step drum (not unlike a player-piano roll), or by a computer (increasingly, the brain of choice).
Two-dimension vision systems which employ TV cameras are already being used to instruct robots -- to tell them the location, for instance, of a particular part on an assembly line -- and further refinements are in the works. Future systems will be better able to gauge all three dimensions, one day making it possible for a robot to spot an obstacle and maneuver around it, or to pluck different pieces from a container and assemble them as easily as a human could. Engineers are working to make robot arms lighter and more flexible, but most of the current research is aimed at improving the robots' ability to see, hear, feel, and possibly smell. Within the near future, they will respond capably to voice commands and will "feel" so accurately that they will be able to handle, if not juggle, fresh eggs. Other pending developments include multiple arms, hand-to-hand coordination, mobility, and self-diagnostic capabilities.
