Don't go shouting "nanotech magic"! Oh, you weren't. Sorry.

So.

This is just about at the limits of current technology. Robonit is a tiny robotic nit that roves your scalp, securing itself to one strand of hair after another with teeny claws, just like a real nit. Power comes from an induction coil, paired to a transmitter worn elsewhere. Movement is painfully slow (due to power constraints), but it works 24/7.

What does it do? This should be apparent by now. As it grips each hair, an LED and photodiode measure its optical properties. A white hair will act somewhat like a bad optical fibre, whereas a dark hair will act rather like a dark hair. Upon detecting a white hair, a small clipper snips it off, close to the scalp.

Over a period of several days, a small swarm of robonits will gradually weed out those rare but glaringly obvious grey hairs, and will then continue to nip others in the bud. Use by blondes not recommended.
-- MaxwellBuchanan, Jun 25 2008

Cue the lawyers when you wake up bald from a badly configured nit.
-- MisterQED, Jun 25 2008


Couldn't it just colour the grey hairs instead?
-- hippo, Jun 26 2008


I was expecting them to have LEDs, and climb out to the end of the strand, where they blink random colours. If you have short hair, it could function as an LED display!
-- Bukkakinator, Jun 26 2008


Right, yes, i like, but i was expecting something slightly different, namely a louse assassin robot, and i think that could be done with a small modification with the use of an ultraviolet LED and a syringe which injects some kind of disinfectant into actual nits.
-- nineteenthly, Jun 26 2008


//Couldn't it just colour the grey hairs// // could function as an LED display!// //a louse assassin robot,// All excellent ideas. Sadly, I think you'll find them covered by claims 103, 145 and 721, respectively.
-- MaxwellBuchanan, Jun 26 2008


This will be the downfall of the polar bear species.
-- napoleonbag, Jun 26 2008


Instead of snipping the grey hairs, the nits should make colourful use of this 'fibre-optic' strand.
-- kuupuuluu, Jun 28 2008


my girl would rather have robosects 24/7 than a single white hair of length longer than 2.2 cm. upon my head.
-- lolzcakes, Jun 30 2008


Poor Santa, he didn't stand a chance...
-- Jinbish, Jun 30 2008


That full-spectrum hair doobrey could maybe be done this way. It's an idea somewhere here, but i can't remember where.
-- nineteenthly, Jun 30 2008



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