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Re: Artificial horizons
From: Trevor Kenchington
Date: 2003 Jul 11, 01:29 -0300
From: Trevor Kenchington
Date: 2003 Jul 11, 01:29 -0300
Bill, Your problem would be getting the mirror to float level, not trimmed by bow or stern, nor with a list to port or starboard. Getting a flat, floating mirror surface shouldn't be difficult and one that maintained a constant orientation to the vertical wouldn't pose any insuperable challenges. But getting that flat mirror to also be level, to better than a tenth of a minute of arc to match the precision of a sextant observation, would be a tall order. You certainly wouldn't do it by sticking a few bits of styrofoam to the back of the mirror. Trevor Kenchington Bill Arden wrote: > This thread has gotten me to thinking ... > > The best thing about a liquid artificial horizon is that it is > gravitationally driven to be flat and level, but it suffers from breezes. > > The best thing about a mirror artificial horizon is that it's > permanently flat, but it's hard to make it level. > > Has anybody tried floating a mirror on a liquid bath? You could glue it > to a piece of styrofoam, and if it were only slightly smaller than the > pan it's floating in, there wouldn't be much room for wind to disturb > the liquid. > > I haven't tried it (this is just a gedanken experiment) - has anybody else? > > Regards, > Bill Arden -- Trevor J. Kenchington PhD Gadus@iStar.ca Gadus Associates, Office(902) 889-9250 R.R.#1, Musquodoboit Harbour, Fax (902) 889-9251 Nova Scotia B0J 2L0, CANADA Home (902) 889-3555 Science Serving the Fisheries http://home.istar.ca/~gadus