"Ричард Фейнман. Surely You're Joking, Mr. Feynman!/Вы, конечно, шутите, мистер Фейнман! (англ.)" - читать интересную книгу автораand could never get everything right. One time he designed a box full of
gears, one of which was a big, eight-inch-diameter gear wheel that had six spokes. The fella says excitedly, "Well, boss, how is it? How is it?" "Just fine!" the boss replies. "All you have to do is specify a shaft passer on each of the spokes, so the gear wheel can turn!" The guy had designed a shaft that went right between the spokes! The boss went on to tell us that there was such a thing as a shaft passer (I thought he must have been joking). It was invented by the Germans during the war to keep the British minesweepers from catching the cables that held the German mines floating under water at a certain depth. With these shaft passers, the German cables could allow the British cables to pass through as if they were going through a revolving door. So it was possible to put shaft passers on all the spokes, but the boss didn't mean that the machinists should go to all that trouble; the guy should instead just redesign it and put the shaft somewhere else. Every once in a while the army sent down a lieutenant to check on how things were going. Our boss told us that since we were a civilian section, the lieutenant was higher in rank than any of us. "Don't tell the lieutenant anything," he said. "Once he begins to think he knows what we're doing, he'll be giving us all kinds of orders and screwing everything up." By that time I was designing some things, but when the lieutenant came by, I pretended I didn't know what I was doing, that I was only following orders. "What are you doing here, Mr. Feynman?" "Well, I draw a sequence of lines at successive angles, and then I'm this table, and lay it out..." "Well, what is it?" "I think it's a cam." I had actually designed the thing, but I acted as if somebody had just told me exactly what to do. The lieutenant couldn't get any information from anybody, and we went happily along, working on this mechanical computer, without any interference. One day the lieutenant came by, and asked us a simple question: "Suppose that the observer is not at the same location as the gunner - how do you handle that?" We got a terrible shock. We had designed the whole business using polar coordinates, using angles and the radius distance. With X and Y coordinates, it's easy to correct for a displaced observer. It's simply a matter of addition or subtraction. But with polar coordinates, it's a terrible mess! So it turned out that this lieutenant whom we were trying to keep from telling us anything ended up telling us something very important that we had forgotten in the design of this device: the possibility that the gun and the observing station are not at the same place! It was a big mess to fix it. Near the end of the summer I was given my first real design job: a machine that would make a continuous curve out of a set of points - one point coming in every fifteen seconds - from a new invention developed in England for tracking airplanes, called "radar." It was the first time I had ever done any mechanical designing, so I was a little bit frightened. I went over to one of the other guys and said, "You're a mechanical |
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