Newsgroups: comp.robotics
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From: c22dlm@kocrsv01.delcoelect.com (David L Mannfeld)
Subject: Re: WANTED: Electronic compasses and gyros.
Message-ID: <1993Oct27.143642.5312@kocrsv01.delcoelect.com>
Originator: c22dlm@koiasw01
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Organization: Delco Electronics Corp.
References: <DULIMART.93Oct25205508@pacific.cps.msu.edu> <af.2062.33.0NAF5F03@mecheng.fullfeed.com>
Date: Wed, 27 Oct 1993 14:36:42 GMT
Lines: 25


In article <af.2062.33.0NAF5F03@mecheng.fullfeed.com>, greg.jackson@mecheng.fullfeed.com (Greg Jackson) writes:

> There are also people that make laser ring gyros which use
> interferometer techniques and relativistic principles to check out
> acceleration.  Those devices work wherever relativity applies (most
> places I can think of) and are pretty accurate.  I think they are core
> devices for aircraft navagation.  The light goes around a circle (hence
                                                            ^^^^^^
  I think this is actual usual a square or a triangle, a circle might be
  a little though to do. :-)
  
> the term "laser ring") in both directions.  When the ring accelerates
> forward, the light on one side of the ring is phase shifted from the
> light that is currently on the other side of the ring.  The phase shift
> is measured from shifts in the interference pattern as the two light
> paths collide. While the shift is pretty small for non-relativistic
> speeds, the light wavelength is smaller still and the system provides
> good sensitivity to acceleration.  A double integral of acceleration
> will yield position but watch out for integrator drift.
-- 
David L. Mannfeld    (317) 451-1327
Department Lead Engineer
Air Controls Software Engineering
Delco Electronics Corp.
