Re: Inertial Navigation ???

From:         pkearn@eircom.net (Paul Kearney)
Date:         13 Mar 2000 09:56:46 -0800
Organization: Ireland On-Line Customer
References:   1
Followups:    1
Next article
View raw article
  or MIME structure

Ed McBride <emcbride@wybron.com> wrote:
::But I keep hearing that people take off in an airplane, fly across
::country, and know where they are within a foot or so.  The only
::explanation I can come up with is that these airplanes must be
::"re-zeroing" rather often.

The INS/IRS systems on Boeing Aircraft (assume very similar on others)
use the DME(radio ground stations) to confirm and update their
position as they travel.

Now with GPS - the NAV systems can be updated even when out in the
Atlantic/Pacific where DME may not be available.  Which i suppose is
''re-zeroing'' itself.

The B737 Flight Managment Computer uses DME/DME cross-bearings to
confirm its location when it knows that it has 2 DME's to work with.

But... your machine wont have this luxury...

i take it that youre talking 3-D for your own project and therefore
counting stepper-motor pulses on a known diameter wheel to indicate
position change from known-origin would be useless ??

good luck with the project anyhow.
paul.