This is a simple robot for extracting needles from haystacks. A wheeled chassis supports a lightweight arm with a tweezer at the end.

The arm picks up an item from the mixed needle/hay pile and sets it across two electical contacts. A quick continuity test checks whether the item is a conductive needle, or non conductive hay.

Hay is piled on one side, needle(s) on the other. The device iterates through the entire pile until all needles have been extracted.

Note that this may not work with wet hay.
-- Galbinus_Caeli, Jul 19 2006

I think Mythbusters did this one to death. They even threw in the kind of needles people used when that saying was first used (bone needles).
-- DrCurry, Jul 19 2006


What if it's a knitting needle? Ahh, gotcha!
-- phundug, Jul 19 2006


Or a pine needle.
-- Texticle, Jul 19 2006


READ NEEDLE-TYPE
IF (NEEDLE-TYPE NOT EQUAL "PINE") AND (NEEDLE-TYPE NOT EQUAL "KNITTING")
PERFORM 100-ITERATE-PILE
ELSE PERFORM 200-SELF-DESTRUCT.
STOP RUN.
-- phundug, Jul 19 2006


Magnets?
-- hidden truths, Jul 19 2006


X-ray + robotic arm?
-- methinksnot, Jul 19 2006


Fire.
-- jmvw, Jul 19 2006


bloodhounds.
-- tcarson, Jul 19 2006


Magnetic bloodhounds with robotic arms set on fire.
-- hidden truths, Jul 19 2006


and x-ray vision. Gotta have that x-ray vision.
-- methinksnot, Jul 19 2006


I want one for the fridge.
-- jmvw, Jul 19 2006


Ambiguous title. Could be read as a needle extractor which is housed in a haystack.

Wouldn't "Extractor for haystack encased needle" be a more accurate title?

Just wearing my El Pedanto hat today.
-- neelandan, Jul 20 2006



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