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Re: [Flightgear-devel] Autopilot and violent roll
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From: Pete M. <AC...@da...> - 2009-10-10 19:59:11
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Alan Teeder wrote: > Do you really expect much help after that "stuff you lot" remark? > Sorry.. guess it my frustration... > As a former autopilot designer I would suggest that what is needed is a rate > limit on roll angle demand within the autopilot. You could also try to add > some roll damping within the autopilot. It is possible that the FDM for your > aircraft is making the simulated aircraft over-sensitive to aileron. > Precisely the problem,. I;m readinga property tree and aparently all aircraft with new heading can Immeseatley "tip" to that bank angle,, u can so that with live controls. dot period . > How this should be implemented within Flightgear I am not in a position to > tell you as I am not familiar with the code, sorry. > > Who I'd like to engage is someone who is familiar witht eh "code", albeit c_++, py or indeed nasal.. This is a problem across the whole system and a mega fault. pete > -----Original Message----- > From: Pete Morgan [mailto:AC...@da...] > Sent: 10 October 2009 20:18 > To: FlightGear developers discussions > Subject: Re: [Flightgear-devel] Autopilot and violent roll > > Actually my motion platform is at the momnet I am taking it one step at > a time.. ie so far its banking left to right by around 10 degree's which > kinda exagarrated the sim and is useful.. > > Anyone as a pilot at the moment can tip the aircfaft to lbank.. However > this jerk needs solving.. SO what you are saying is .. stuff FlightGear > and its your problem.. > > pete > > > Curtis Olson wrote: > >> I haven't looked at these autopilot configurations (at least not for a >> long time) but off the top of my head, I think this can all be fixed >> by tuning the autopilot. >> >> For instance, lowering the max aileron deflection from (-1 ... 1) down >> to maybe (-0.1 ... 0.1) might be an interesting thing to start with. >> These are normalized values so +/-1 represents full deflection and 0.1 >> represents 1/10th of full deflection. If the autopilot is hitting you >> with full instantaneous aileron deflection that might be part of the >> issue. >> >> The other thing to look at is tuning the actual PID gains. These are >> obscured a bit given that we are using a slightly different form of >> the PID algorithm compared to what you might see in a Control >> Theory-101 class. I believe there is an autopilot tuning README and >> it just takes some fiddling around to see what changing the different >> values will accomplish. There's an art (maybe part science) to tuning >> autopilots ... I've yet to meet an expert in that area, but they must >> exist ... they are probably locked in the basement of Airbus and >> Boeing and various UAV companies and not allowed to leave their cells. :-) >> >> Curt. >> >> >> >> On Sat, Oct 10, 2009 at 1:56 PM, Pete Morgan <AC...@da... >> <mailto:AC...@da...>> wrote: >> >> I'm working on my motion sim for xmas. Its powered by a vacum >> cleaner atmo.. >> One BIG BIG problem - am basicng the cockpit on Bravo and 787 >> >> The autopilot heading bug is very violent and JERKS to direction.. >> >> How can we solve that problem please because on my motion platform, I >> cant keep up with the drastric movements. Actually I can, but this is >> where there is a problem.. >> >> the behaviour of bank is performing well with the Ardiono/pneumatics >> card firing off the valves, >> >> however the violent values from the autopilot when auto pilot is >> engaged >> is causing a problem.. >> >> I've damped it down in my arduino/python middle man code, >> >> But I think this problem is an actual flightgear problem.. >> >> Any one offer me some advice which area of code to look at please... >> >> eg I could damp it in nasal script ? >> >> pete >> >> >> > ---------------------------------------------------------------------------- > -- > >> Come build with us! The BlackBerry(R) Developer Conference in SF, CA >> is the only developer event you need to attend this year. >> Jumpstart your >> developing skills, take BlackBerry mobile applications to market >> and stay >> ahead of the curve. Join us from November 9 - 12, 2009. Register now! >> http://p.sf.net/sfu/devconference >> _______________________________________________ >> Flightgear-devel mailing list >> Fli...@li... >> <mailto:Fli...@li...> >> https://lists.sourceforge.net/lists/listinfo/flightgear-devel >> >> >> >> >> -- >> Curtis Olson: http://baron.flightgear.org/~curt/ >> <http://baron.flightgear.org/%7Ecurt/> >> ------------------------------------------------------------------------ >> >> >> > ---------------------------------------------------------------------------- > -- > >> Come build with us! The BlackBerry(R) Developer Conference in SF, CA >> is the only developer event you need to attend this year. Jumpstart your >> developing skills, take BlackBerry mobile applications to market and stay >> ahead of the curve. Join us from November 9 - 12, 2009. Register now! >> http://p.sf.net/sfu/devconference >> ------------------------------------------------------------------------ >> >> _______________________________________________ >> Flightgear-devel mailing list >> Fli...@li... >> https://lists.sourceforge.net/lists/listinfo/flightgear-devel >> >> > > > ---------------------------------------------------------------------------- > -- > Come build with us! The BlackBerry(R) Developer Conference in SF, CA > is the only developer event you need to attend this year. Jumpstart your > developing skills, take BlackBerry mobile applications to market and stay > ahead of the curve. Join us from November 9 - 12, 2009. Register now! > http://p.sf.net/sfu/devconference > _______________________________________________ > Flightgear-devel mailing list > Fli...@li... > https://lists.sourceforge.net/lists/listinfo/flightgear-devel > > > ------------------------------------------------------------------------------ > Come build with us! The BlackBerry(R) Developer Conference in SF, CA > is the only developer event you need to attend this year. Jumpstart your > developing skills, take BlackBerry mobile applications to market and stay > ahead of the curve. Join us from November 9 - 12, 2009. Register now! > http://p.sf.net/sfu/devconference > _______________________________________________ > Flightgear-devel mailing list > Fli...@li... > https://lists.sourceforge.net/lists/listinfo/flightgear-devel > |