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Navy Declassifies Details
Of Pigeon Guidance Project

A study of missile guidance by pigeon pecking has been taken out from under wraps by the Navy. At the same time, perhaps to calm fears of guidance designers, the Navy made clear that the project has been discontinued.

Started during World War II, Project Orcon (for organic control) was a try-anything approach to solving some then-current problems. Guidance systems for homing missiles were being easily countermeasured and the Navy thought animals might have potential as a jam-proof control element. Pigeons were selected for trial because they were light, easily obtainable and adaptable. Their job was to ride inside a missile and peck at an image of a target picked up by a lens in the missile's nose. The pigeon's pecking of the target image was translated into an error signal that corrected the simulated missile's simulated flight.

The project was revived in 1948 and carried further. In simulated rocket tests, the pigeons produced "surprisingly good results." The researchers were convinced that a pigeon could successfully guide a speeding missile under optimum conditions, compensating for his own and the missile's errors.

But after three years of equipment development and testing, the project was abandoned because the range of the Orcon system could be no greater than the range of any optical system and the system could be used only in the daytime. The trainer used target images photographed in color by a jet plane, which made picture-taking dives at a destroyer and a freighter in open sea.

Trainee pigeons were started out in the primary trainer pecking at slowly moving targets. They were rewarded with corn for each hit and quickly learned that good pecking meant more food. Eventually pigeons were able to track a target jumping back and forth at five inches per second for 80 seconds, without a break. Peck frequency turned out to be four per second, and more than 80 percent of the pecks were within a quarter inch of the target. The training conditions simulated missile-flight speeds of about 400 miles per hour.

The image was shown under a glass screen coated with stannic oxide to make it electrically conducting. Through circuitry based on the Wheatstone Bridge principle, pecks on the glass were translated into distance right and left and up and down from the center lines.

The target was moved by a small mirror controlled by a servo. The control circuits were such that if the pigeon stopped tracking, the target image would drift rapidly away from the center of the screen. This forced the pigeon to correct not only his own pecking errors, but those introduced by the yawing of the missile. It turned out that 55.3 per cent of the runs made were successful--that is, the pigeons were able to keep the target image on their screens for the duration of more than half their flights.

If pigeon guidance did not get very far in the Navy, it did have one valuable offshoot. The electrically conducting glass was later used in many radar displays. (electronic design, November 25, 1959, p. 16)

This article speaks for itself. Any comment from me probably would be superfluous.–Steve Scrupski

Steve Scrupski is a former Editor-in-Chief of Electronic Design. Now semi-retired, he can be reached at scrupski@worldnet.att.net.

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