NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: FOG's, was Re: automatic celestial navigation
From: Paul Hirose
Date: 2008 Jan 29, 12:27 -0800
From: Paul Hirose
Date: 2008 Jan 29, 12:27 -0800
George Huxtable wrote: > Nevertheless, isn't it the case that there is > effectively zero long-term drift in the orientation sensing of these > devices; quite different from the behaviour of their mechanical > predecessors? Unfortunately, errors are still present. The was no upward jump in INS performance when ring laser gyros were introduced. In fact, the most stable gyroscope system yet created (.0005 arc second per year) uses spinning spheres floating inside close-fitting vacuum chambers, similar to the SPN/GEANS INS arrangement. It's on Gravity Probe B: http://einstein.stanford.edu/sitemap.html But SPN/GEANS uses an electromagnetic motoring action to spin up its gyros, rather than gas jets. And the pickoff is optical rather than magnetic. -- I block messages that contain attachments or HTML. --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To , send email to NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
