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Old February 15th 04, 12:03 AM
Jim Doyle
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Default Pigeon guided missiles?!

I found this earlier today, it may not be new to yourselves - but the
thought of some pigeon tapping away frantically inside a speeding missile
had me in stiches!

http://www.findarticles.com/cf_dls/m.../article.jhtml

Hope it tickles something,

Jim Doyle

Here it is in full:
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)