> Thanks for your comments - they fit with what I'm finding & > thinking. > > Sure, in piloted aircraft takeoff is handled by the pilot, who is > able to cope with a wide range of possible failures at this > critical phase of flight, but I'm trying to work towards a UAV > control framework, from takeoff roll to landing stop, so that's why > I'm messing about with automated takeoffs, landings and scripted > flight etc. > > I also find auto takeoffs, landings and scripted flight useful for > general FDM config & controller tuning for piloted aircraft - it > eliminates variations due to the pilot, in this case me:) > > LeeE >
My experience with UAV control systems is that scheduling gains with airspeed is a good idea if you want control over a wide envelope. It is difficult enough to make the vehicle stable over the entire flight envelope. If you want anything approaching optimum control, you need to have gain settings for at least 2 different airspeed regimes. The discontinuities that cause the "kick" can be eliminated by doing a smooth interpolation between the gains (rather than suddenly changing them when airspeed crosses a given threshold). I've had success using a "low speed" and "high speed" set of gains with linear interpolation between them. Of course, I don't know how you could do this in flightgear. Perhaps a nasal script could do the interpolation and update the PID gain properties? -Jeff ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
