Jim Wilson writes: > > David Megginson <[EMAIL PROTECTED]> said: > > > Jim Wilson writes: > > > > > I'd like to project (simplisticly) airspeed in 10 seconds, primarily for > > > autothrottle accuracy with jet engines, but also for display purposes. > > > > > > The idea would be something like this: > > > > > > airspeed_in_10secs = airspeed_kt + > > > (airspeed_kt - last_airspeed_kt) * (10/dt); > > > > You might want to increase your sample rate a bit: for example, you > > could sample every second and do a rolling weighted average of the > > acceleration (delta airspeed) over the past ten seconds. > > That was my original thought, but I was afraid that it would extend the > upper/lower limits (make larger predictions) and my readings would come up > short. So it seemed to be safer, and of course easier, to base the data on > what was happening at that instant, rather than over time. Jim
If you aren't familiar with a Kalman Filter you *really* should read this http://www.cs.unc.edu/~welch/media/pdf/maybeck_ch1.pdf Coding one of these is actually quite straight forward http://cvs.sf.net/cgi-bin/viewcvs.cgi/autopilot/onboard/rev2/ahrs.c?rev=HEAD&content-type=text/vnd.viewcvs-markup Norman _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
