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Exponential for pitch/roll/rudder axes

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Unless I have not seen it, it appears that only linear relationships between controller and pitch/roll/rudder deflections can be setup. I prefer an exponential setup so the amount of movement near the centering point is much less than near the extremes. The Extra 330 is so fast in response, it is difficult to fly smoothly. I also notice that the Extra has a second order damped response (it rings/oscillates a little with a step input) - is that also for the actual aircraft?

 

Love FS2 in VR - I can get 75fps (DK2) easily - still would like to have ATW for those few times I can't maintain 75fps

 

Dave

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Conveying an answer from the Ipacs website:

 

No, there's zero input lag in the Extra IRL, or any other plane with a direct stick-flightcontrol connection.

 

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Conveying an answer from the Ipacs website:

 

I don't think the oscillation the OP is talking about is related to flight control lag, but rather to the flight dynamics per se, and specifically to the characteristics of the aircraft short period mode.

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I don't think the oscillation the OP is talking about is related to flight control lag, but rather to the flight dynamics per se, and specifically to the characteristics of the aircraft short period mode.

 

Yah, I kind of take the oscillation as a separate issue/question.

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Yes, sorry that I didn't make this into three separate points:

 

1) Would like exponential option for control setup - so that more movement is needed near the center trim position for a degree of control fin deflection than for the extreme (at least have a sensitivity adjustment)

2) The Extra330 seems to oscillate a little for a couple cycles with an abrupt control movement and is difficult to fly smoothly without the exponential setup ( or need less sensitivity)

3) Would like ATW implemented for the few times that FPS is less than 75 (or 90 for the CV1 /  Vive)

 

EDIT: How about a 4th point:  Developers, please keep the FPS high and move any added features (AI aircraft, ATC, aircraft systems, weather, multiplayer, etc) to other CPU cores - previously, War Thunder was the only flight sim that provided 90fps without ATW (super smooth!!) - now FS2 does also!!!! 

 

Dave

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Three answers from the forum: 2 from Developers. http://www.ipacs.de/forum/showthread.php/7559-Exponential-for-pitch-roll-rudder-axes?p=35224#post35224

User: Overloaded
 

Any shielded horn balances on the tail would cause a smaller control surface movement for the initial force on the fore/aft stick and the rudder.  The movement of the stick and rudder would also be small, this would be hard to reproduce on a joystick.  Very simple aeroplanes might have no balancing and complex hydraulic controls in large planes have artificial feel and trim for low and very high speed (Mach effects) flight.

If Aero has a reduced control effect for the initial movement of the stick or rudder it would be a reasonable simulation of aerodynamic balancing.  It might be better if it was adjusted in Aero for individual aircraft instead of the user only having a single broad input which would affect all of the planes.

 

Ipacs Support:
 

Creating an exponential function for some functions has indeed problems as it influences all airplanes.
 
We could instead publish simple instructions on how to tweak each airplane to have different behaviour for people who need this. It can already be done by manually editing the TMD file.

 

IPacs Developer: JetPack
 

Hey,
 
Currently Aerofly implements a proportional stick deflection ratio (simulated deflection to real control stick deflection is a constant). Actual centering forces from spring loaded trims, aerodynamic trims, aerodynamic forces and forces caused by acceleration (e.g. mass inertia of the controls), friction and so on are not simulated currently. And because only very few, mostly expensive joysticks actually have a true force feedback with a moving neutral position one can say that the hardware isn't quite there yet. Almost all devices available on the market have a spring loaded centering mechanism that brings the joystick to the exact center. However this is not how real aircraft operate. The force neutral point could be quite far forward or aft depending on the trim setting.
 
Also, the majority of input devices affordable today have a stick that is much much shorter than the in the real world aircraft. A lot of airliners in the Aerofly FS 2 have a yoke that is hinging near the flight deck floor. Unless you lengthen your joystick you will probably never get the same fine control inputs as in the real world on any desktop flight simulator.
 
Personally I have removed my joystick spring and also have abandoned any non-linear control behavior since I stared flying in the real world. The gliders that I've flown in the real world all only require very small inputs and using something like expo in the simulator would make me overcontrol the aircraft in real world. So personally for me expo is an absolute no-go. But I understand that you want to control the aircraft realistically without purchasing more expensive hardware, so maybe we can do something like expo.
 
The response of the Extra to a step-input is what I would expect. All aircraft that I have flown IRL have had such a reaction. First pitch input, then angle of attack build up, then stick release, continuation of the rotation and then return to the aerodynamical neutral position in an oscillating fashion.
 
Any input that you make will add a torque onto the airframe, which over time will start to spin the aircraft faster (pitch rate, roll rate). The speed at which the aircraft increases its pitch/roll/yaw rate depends on its inertia around the corresponding axis. Me model this inertial and the mass distribution physically accurate and in the .tmd file of each aircraft.
 
Once the input is neutralized the aircraft is still spinning and only aerodynamic effects such as the stabilizing effect of the tail surfaces are creating a stabilizing torque to dampen and counteract the rotation speeds. Depending on the type of airplane, its center of gravity location and the rotation axis an oscillating reaction can be observed, it's very typical for the pitch axis for example. With a short and abrubt input the real world aircraft and the Aerofly FS 2 aircraft (non-computer stabilized) show a brief angle of attack oscillation followed by the much longer phygoid oscillation.
 
Cheers,
Jan

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