From: LeeE <le...@sp...> - 2008-04-15 06:08:23
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On Monday 14 April 2008 18:55, Melchior FRANZ wrote: > * Curtis Olson -- Monday 14 April 2008: > > Let's say I want to do a simple moving average ... so the new > > value is (let's say) 9 parts the previous filtered value + 1 > > part of the latest sensor reading. Doing that as a simple > > average though will glitch if your values are coming in around > > 0/360. > > FlightGear has an aircraft.angular_lowpass() in > $FG_ROOT/Nasal/aircraft.nas. It filters sin() and cos() > separately, and builds the angle from that again. Worked well in > my tests. > > m. Ah - that sounds good. Using an exponential filter on heading produced a glitch but as it was resolved so quickly (0.45 sec) it only resulted in a small 'twitch' in flight, in most cases, but I'm sure there would be bigger problems if I was trying to follow an exact 0 deg course. LeeE |