Part 32

None of these steps is as clear-cut or separate as it may seem without some digging into history and an analysis of what we find. For example, while we generally consider that the loom was simply mechanized during the dawn of industrial revolution, the seeds of computer control were sown by Jacquard with punched-card programming of the needles in his loom. Neither is it sufficient to say that the present spectacle of automated pushbutton machines producing many commodities is no different from the introduction of mass-produced tractors. Tractors, after all, displaced horses; the computer-controlled factory is displacing men who don’t always want to be put out to pasture.

Automation is radically changing our lives. It is to be hoped that intelligent and humane planning will facilitate an orderly adjustment to this change. Certainly workers now toil in safer and pleasanter surroundings. It is reported that smashed toes and feet, hernia, eye trouble, and similar occupational accidents have all but disappeared in automated automobile plants. Unfortunately other occupational hazards are reportedly taking the place of these, and the psychological trauma induced by removal of direct contact with his craft has given more than one worker stomach ulcers. Let us investigate this transfer of contact from man to computer-controlled machine.

A paper presented at the First Congress of the International Federation of Automatic Control, held in Moscow in 1960, uses as its introductory sentence, “Automatic control always involves computing.” The writer then points out that historically the computing device was analog in nature and tied so closely with the measuring and control elements as to be indistinguishable as an actual computer. In more recent history, however, the trend has been to separate the computer. With this trend is another important change, that of using the digital computer in automatic control.

One of the first papers to describe this separate computer function is “Instrument Engineering, Its Growth and Its Promise,” by Brown, Campbell, and Marcy, published in 1949. “Naturally,” the authors state, “a computer will be used to control the process.” Not a shop foreman or an engineer, but a computer. Watt’s “flyball” governor pioneered the field; more recent and more obvious examples of control by computers include ships guided by “Iron Mike” and airplanes flown by the automatic pilot. These were analog devices, and the first use of a digital computer as a control was in 1952, quite recently in our history. This airborne digital control computer was built by Hughes and was called “Digitac.”

Since most industries have been in existence for many years, far antedating aviation, electronics, and the modern computer, the general incorporation of such control has been difficult both because of the physical problem of altering existing machines and the mental phenomenon of inertia. Factory management understandably is slow to adopt a revolutionary technique, and most control systems now in use in industry are still analog in nature. However, where new plants are built from the ground up for computer control, the results are impressive. Designed by United Engineering, the Great Lakes 80-inch hot strip mill automatically processes 25-ton slabs of steel. More than 1,000 variables are controlled, and 200 analog signals and 100 digital computer-generated signals are used in the process. The steel sheets are shot out of the rolls at some 45 miles an hour, or about 66 feet a second! A human supervisor would have a difficult job just watching the several hundred signals related to thickness, temperature, quality, and so on, much less trying to think what to do if he noticed something out of specifications. This would be roughly analogous to an editor trying to proofread a newspaper as it flashes by on the press and making corrections back in the linotype room before any typographical errors were printed. The new computer-controlled mill has an output of about 450,000 tons a month, twice that of the next largest in operation.

American control experts who attended the Moscow conference brought back the information that Russian effort in computer control is greater than that in the United States, and that the Russians are more aware of what we are doing in the field than we are of their progress. Their implementation of modern computer control may be made easier because their industries are newer and do not represent such a long-established and expensive investment in hard-to-modify existing equipment.

Basically, at least, computer control is simple and can be compared to the feedback principle that describes many physical systems including the workings of our own bodies. In practice, the computer can be put in charge of producing something, and by sampling the output of its work can constantly make corrections or improvements that are desired. This is of course an extreme simplification, and the control engineer speaks of “on-line” operation, of adaptive systems that adjust to a changing environment, of predictive control, and so on. One vital requirement of the computer involved in a control process, obviously, is that it cannot take its time about its computations. The control computer is definitely operating “on the line”; that is, in real time, or perhaps even looking ahead by a certain amount so that it can not only keep up with production but also predict forthcoming changes and make corrections in time to be of use.

The human process controller is stuck with methods like those of the cook who mixes up his recipe with a spoonful of this, and three pinches of that, sniffs or tastes the batter subjectively, and may end up with a masterpiece or a flop. Computer control processes the same batter through the pipes at a thousand gallons a minute and catches infinitesimal variations in time to correct them before the hotcakes are baked. In effect it makes hindsight into foresight by compressing time far more than man could hope to do.

Early applications of the computer in industrial processes were simply those of data “loggers,” or monitors. It was still up to the human operator to interpret what the computer observed and recorded, and to throw the switch, close the valve, or push the panic button as the case demanded. Actual computer control, the “closing of the loop” as the engineers call it, is the logical next step. This replaces the human operator, or at least relegates him to the role of monitor.

The Great Lakes hot-rolling steel mill has been mentioned as an example of complete computer control. In Hayange, France, the first European completely automated steel-beam mill is slated to go into operation late in 1962. The Jones & Laughlin Steel Corporation in this country uses a digital computer system to control continuous annealing in its Aliquippa, Pennsylvania, plant, and is evaluating an RCA computer-controlled tin-plating line operating at 3,000 feet a minute. Newer computer-control applications in the offing include sintering and other metal production operations.

Minneapolis-Honeywell

Boston ice cream makers, H. P. Hood & Sons, use computer to make pushbutton ice cream. Analog computer thinks out recipes, punches them on cards to operate valves. ]

To those of us who consume it, ice cream may not seem a likely candidate for computer control. However, the firm of H. P. Hood & Sons uses computer control in its blending operation, finding it 20,000 times as fast, and more accurate than when handled by human operators, since computer controls hold mixes within one-tenth of 1 per cent accuracy. Automation is a significant breakthrough in this industry, whose history goes back 110 years, and in baking, which is a little older. The Sara Lee bakeries use the computer too in assembling the ingredients for their goodies. To bake such cakes, Mother will have to get herself a computer.

Minneapolis-Honeywell furnished the computer for the ice-cream control; this same company delivered a system for the Celanese Corporation of America’s multimillion dollar acetyl manufacturing plant at Bay City, Texas. The new plant produces a petrochemical used in plastics, paint, synthetic rubber, dye, fibers, and other products. Going “on-stream” in 1962, the Celanese plant will produce half a billion pounds of chemicals annually.

Russia has been mentioned as active in industrial computer control. A case in point is the soda plant at Slavyansk in the Donets Basin, which was recently test-operated for a continuous period of 48 hours by computer. An unusual feature of this test was that the computer was in Kiev, almost 400 miles away. A wire link between the two cities permitted monitoring and control of the plant from Kiev in what the Russians claim as the first remote automatic operation of such a plant.

Other Soviet achievements include two large-scale automatically controlled installations. In oil-field operation at Tataria, gas and oil outputs from many wells are monitored and controlled from a central station, dropping the work force required from 600 to 100. The other installation controls irrigation servicing 9,000 acres. A desktop control handles the pumping of water from the Syr Darya River through underground pipes, and distribution to Uzbekistan cotton fields. The Russians have also designed an automatic distillation unit for the Hungarians. With an annual capacity of a million tons, the unit was installed in the large Szoeny refinery and scheduled for operation by 1962.

Refineries in the United States are also employing automatic controls in their operations. Phillips Petroleum installed a digital computer control system in its Sweeney, Texas, plant to achieve maximum efficiency in its thermal cracking process. In the first step of an experimental program, Phillips, working with Autonetics computer engineers, used a digital computer to plan optimum furnace operation. An initial 10 per cent improvement was achieved in this way, and a further 6 per cent gain resulted when a digital computer was installed on-line to operate the cracking furnace.

The Standard Oil Company of California is using an IBM 7090 in San Francisco to control its catalytic or “cat” cracking plant in El Segundo, some 450 miles away. The need for computer speed and accuracy is shown by the conditions under which the cracking plant must operate continuously with no shutdowns except for repair. Each day, two million gallons of petroleum is mixed in the cracker with the catalyst, a metallic clay. The mixing takes place at incandescent heat of 1,000° F., and the resulting inferno faces operators with more than a hundred changing factors to keep track of, a job feasible only with computer help.

Another use of computer control in the petroleum industry is that of automatic gasoline blending, as done by the Gulf Oil Corporation. A completely electronic system is in operation at Santa Fe Springs, California. The system automatically delivers the prescribed quantities of gasoline for the desired blend. In case of error or malfunction of equipment, the control alerts the human supervisor with warning lights and an audible alarm. If he does not take proper action the control system automatically shuts itself off.

From the time the war-inspired industry of synthetic rubber production began in 1940 until very recently, it has been almost entirely a manual operation. Then in 1961 Goodyear Tire & Rubber introduced computer control into the process at its Plioflex plant in Houston, Texas. Goodyear expects the new system to increase its “throughput” and also to improve the quality of the product through tighter, smoother control of the complicated operation. Other chemical processors using computer control in their plants include Dow Chemical, DuPont, Monsanto, Union Carbide, Sun Oil, and The Texas Company.

Adept at controlling the flow of material through pipes, the computer can also control the flow of electricity through wires. An example of this application is the use of digital computers in electric-utility load-control stations. A typical installation is that of the Philadelphia Electric Company in Philadelphia, the first to be installed. Serving 3-1/2 million customers, the utility relies on a Minneapolis-Honeywell computer to control automatically and continuously the big turbine generators that supply electric power for the large industrial area. The memory of the computer stores data about the generators, transmission-line losses, operating costs, and so on. Besides controlling the production of power for most economy, the computer in its spare time performs billing operations for exchange of power carried on with Pennsylvania-New Jersey-Maryland Interconnection and Delaware Power & Light Company and Atlantic City Electric Company.

Other utilities using computer control are the Riverside Power Station of the Gulf States Utilities Company, Southern California Edison, and the Louisiana Power & Light Company’s Little Gypsy station in New Orleans.

Another industry that makes use of a continuous flow of material is now being fitted for computer control, and as a result papermakers may soon have a better product to sell. IBM has delivered a 1710 computer to Potlach Forests, Inc., in Idaho for control of a paperboard machine 500 feet long. Papermaking up to now has been more art than science because of the difficulty of controlling recipes. With the computer, Potlach expects to make better paper, have less reject material, and spend less time in changing from one product run to another.

Showing that automatic control can work just about anywhere, the English firm of Cliffe Hill Granite Company in Markfield, Leicestershire, controls its grading and batching of granite aggregate from a central location. Besides rock-crushers, cement plants like Riverside Cement Company use computer control in the United States.

Thus far most of the computer control operations we have discussed are in the continuous-processing fields of chemicals or other uniform materials. The computer is making headway in the machine shop too, although its work is less likely of notice there since the control panel is less impressive than the large machine tool it is directing. Aptly called APT, for Automatically Programmed Tools, the new technique is the brainchild of M.I.T. engineer Douglas Ross. Automatic control eliminates the need for drill jigs and other special setup tools and results in cheaper, faster, and more accurate machine work.

International Business Machines Corp.

Controlled by instructions generated by IBM’s AUTOPROMPT, a Pratt & Whitney Numeric-Keller continuous-path milling machine shapes a raw aluminum block (upper left) into the saddle-shaped piece shown at right. The surface is a portion of a geometric shape called a hyperbolic paraboloid. ]

A coded tape, generated by a computer, controls the milling machine, drill press, or shaper more accurately than the human machinist could. In effect, the computer studies a blueprint and punches out instructions on tape that tell the machine what it is to do, how much of it, and for how long. Huge shaping and contouring machines munch chunks of metal from blanks to form them into complex three-dimensional shapes. Remington Rand UNIVAC and IBM are among the companies producing computers for this purpose. The trend is to simpler, more flexible control so that even small shops can avail themselves of the new technique. In a typical example of the savings possible with “numerical” tape control, these were the comparative costs: