NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: accuracy of automatic celestial navigation
From: Brian Whatcott
Date: 2002 Dec 9, 18:07 -0600
From: Brian Whatcott
Date: 2002 Dec 9, 18:07 -0600
It's encouraging to see a post like Paul's. Knowledgable, steady, helpful.... Brian W At 01:42 PM 12/9/02, Paul Hirose, you wrote: >... >An INS can handle motion far more violent than a seagoing vessel will >experience. ... > > In the days before GPS, how could the instaneous position in flight be > > independently determined sufficiently accurately, for testing purposes? ... >A tracking instrument on the ground called a cinetheodolite is the >old-tech method. >http://www.serve.com/mahood/nellis/ttr/sln5.htm > >http://www.emitechnologies.com/optped.html > >http://www.acq.osd.mil/te/mrtfb/commercial/afftc/time.html > > >The 1984 Bowditch explains this better than I can: > >"Since an accelerometer cannot distinguish between a kinematic >acceleration and a gravitational acceleration, any uncertainty in the >gravitational environment manifests itself as a system error.... Brian Whatcott Altus OK Eureka!