Re: [Flightgear-devel] Autopilot and violent roll

2009-10-14 Thread Pete Morgan
leee wrote: > On Saturday 10 Oct 2009, Pete Morgan wrote: > >> Roy Vegard Ovesen wrote: >> >>> On Saturday 10 October 2009 22:33:01 Curtis Olson wrote: >>> Really, this is all in how the autopilot is tuned and configured. FlightGear doesn't model realistic control

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-14 Thread leee
On Wednesday 14 Oct 2009, Alan Teeder wrote: > > -Original Message- > > From: leee [mailto:l...@spatial.plus.com] > > > > > Did you try scheduling your autoplilot´s height-error to > > > pitch demand gain with 1/V (speed inverse) ? > > > > > > Alan > > > > Re-read the end of the paragraph a

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-14 Thread Alan Teeder
> -Original Message- > From: leee [mailto:l...@spatial.plus.com] > > > > Did you try scheduling your autoplilot´s height-error to pitch > > demand gain with 1/V (speed inverse) ? > > > > Alan > > Re-read the end of the paragraph after the one you quoted above ;-) > > LeeE Red Face (me

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-13 Thread leee
On Monday 12 Oct 2009, Alan Teeder wrote: > > -Original Message- > > For the faster and more > > > maneuverable military jets though, I found that I really needed > > guaranteed higher rates to both ensure a crisp response and > > avoid instabilities. For example, I could tune an > > altit

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-12 Thread Alan Teeder
> -Original Message- For the faster and more > maneuverable military jets though, I found that I really needed > guaranteed higher rates to both ensure a crisp response and avoid > instabilities. For example, I could tune an altitude-hold cascade > that would work fine at speeds up to 40

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-12 Thread leee
On Sunday 11 Oct 2009, Roy Vegard Ovesen wrote: > On Sunday 11 October 2009 14:04:19 Kishore wrote: > > Not having a common time base reference for the various > > subsystems can lead to varying performance based on the > > underlying hardware on which flightgear is run. The > > PID/Autopilot tunin

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-12 Thread leee
On Sunday 11 Oct 2009, Alan Teeder wrote: > > -Original Message- > > From: leee [mailto:l...@spatial.plus.com] > > > > > ie if u stick in a new value to the FDM then it will react.. > > > That sucks in my oioiion.. I how have to create my own craqo > > > to make the model. that sucks to me.

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-11 Thread Roy Vegard Ovesen
On Sunday 11 October 2009 14:04:19 Kishore wrote: > > Not having a common time base reference for the various subsystems can lead > to varying performance based on the underlying hardware on which flightgear > is run. The PID/Autopilot tuning for a given model should not vary based on > the hardwar

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-11 Thread Kishore
On Sunday 11 Oct 2009 4:30:08 pm Curtis Olson wrote: > > I think that your premise that autopilots need to run at very high frame > > rates is not realistic. > > > > When I first got into autopilots and simulation, back in the 60´s, all of > > our models had as the final element a 0.1 second low pa

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-11 Thread Curtis Olson
On Sun, Oct 11, 2009 at 3:39 AM, Alan Teeder wrote: > First, thanks for the quick into to Flightgear´s autopilot. > > I think that your premise that autopilots need to run at very high frame > rates is not realistic. > > When I first got into autopilots and simulation, back in the 60´s, all of > o

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-11 Thread Alan Teeder
> -Original Message- > From: leee [mailto:l...@spatial.plus.com] > > > > ie if u stick in a new value to the FDM then it will react.. That > > sucks in my oioiion.. I how have to create my own craqo to make > > the model. that sucks to me.. > > > > pete > > You really need to chill a bit

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-10 Thread leee
On Saturday 10 Oct 2009, Pete Morgan wrote: > Roy Vegard Ovesen wrote: > > On Saturday 10 October 2009 22:33:01 Curtis Olson wrote: > >> Really, this is all in how the autopilot is tuned and > >> configured. > >> > >> FlightGear doesn't model realistic control surface deflection > >> rates so it's

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-10 Thread Jon S. Berndt
> From: Roy Vegard Ovesen [mailto:roy.v.ove...@haugnett.no] > > Control surface deflection rate can be limited by inserting a low-pass > filter > between the output of the final PID-controller and the control surface. > THis > is done in the autopilot config file. > For JSBSim aircraft, you also

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-10 Thread Pete Morgan
Roy Vegard Ovesen wrote: > On Saturday 10 October 2009 22:33:01 Curtis Olson wrote: > >> Really, this is all in how the autopilot is tuned and configured. >> >> FlightGear doesn't model realistic control surface deflection rates so it's >> possible to command an instantaneous deflection of the c

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-10 Thread Roy Vegard Ovesen
On Saturday 10 October 2009 22:33:01 Curtis Olson wrote: > > Really, this is all in how the autopilot is tuned and configured. > > FlightGear doesn't model realistic control surface deflection rates so it's > possible to command an instantaneous deflection of the control surfaces. Control surface

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-10 Thread Curtis Olson
On Sat, Oct 10, 2009 at 3:23 PM, Heiko Schulz wrote: > If you mean this sudden banking when after reaching a new wayoint: yes. It > is known and is still on the bug-list on flightgear.org anywhere. > > There were some aircraft authors who had a workaround with nasal- to my > knowledge the 787 For

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-10 Thread Heiko Schulz
> > This is a problem across the whole system and  a mega > fault. > If you mean this sudden banking when after reaching a new wayoint: yes. It is known and is still on the bug-list on flightgear.org anywhere. There were some aircraft authors who had a workaround with nasal- to my knowledge t

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-10 Thread Pete Morgan
t;, 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...@daffodil.uk.com] > Sent: 10 October 2009 20:18 > To: FlightGear developers discussions > Subject: Re: [Flightgear-d

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-10 Thread Alan Teeder
er 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 usef

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-10 Thread Pete Morgan
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 y

Re: [Flightgear-devel] Autopilot and violent roll

2009-10-10 Thread Curtis Olson
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