On Jan 22, 7:10*am, Andy wrote:
On Jan 22, 3:05*am, Chris Reed wrote:



noel.wade wrote:
On Jan 21, 8:00 pm, Eric Greenwell wrote:

There are a number of programs that do this, such as SeeYou, simulator
software (Condor?), even commercial programs that reconstruct a flight
from gps data for accident and other investigations. T2T (track to

Eric -

Yes I have. *The catch is that this project isn't mine; I'm
volunteering my time for it. *And the people I'm working with don't
want the end-result to be tied to any licensing fees or restrictions
on use of the code.
*sigh* *shrug*

Thanks all,

--Noel

XC Soar is Open Source, which might work if the GPL restrictions
wouldn't affect the exploitation of the project (this would require you
to make any modified XC Soar code modules available under the GPS terms,
but not *interfacing modules which would stay proprietary).

I'd contact the Aerospace Engineering department at a university near
you. *Most graduate programs and some undergraduate ones have analytic
tools they use to do optimal estimation for a state-space
representation of aircraft. To do some of the things you are asking
about I suspect you'd need a full 6 degree of freedom model. Depending
on what the inputs are, you may not be able to fully estimate the
aircraft state - there would be too many unknowns. For instance,
because you don't have attitude information (none of the Euler
angles), you wouldn't be able to cleanly distinguish between gusts
displacing the aircraft and control inputs. You would likely need to
assume coordinated flight and no wind gusts. Some simple Kalman
filters should help, as Dave says.

9B

Um, depending on what he's trying to do, the Kalman filters
in the GPS could make life very difficult. Adding another
Kalman filter in back of the filter already in the GPS engine
is not likely to help. And every brand of GPS (and potentially
every software revision of the same brand) may have different
filtering.

Here's an experiment conducted a few times, with a GPS
engine in a car:
Drive at high speed
Disable the antenna
Slow rapidly and turn 90 degrees
Speed up
Enable antenna

What do you think the GPS output shows ?

Hope that helps clarify the problem,
Best Regards, Dave "YO electric"