RC Feel parameter?


Tuning guide mentions RC feel parameter. But I can’t find this parameter in the parameter list.
Although there are sliders corresponding to this crispness/sluggishness.

To which parameter leads this slider?

Hi Pakman, The RC_FEEL parameter changed to ATC_INPUT_TC, but I do not remember from which version of copter the change happened.

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ATC_INPUT_TC = Option: 0.50 very soft, 0.20 soft, 0.15 medium, 0.10 crisp, 0.05 very crisp.

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The new parameter ATC_INPUT_TC is the time constant for the rise time to get to 63% of the requested attitude if you were to make a step input in stabilize mode. The default is 0.15 seconds. If you lower this value be sure to observe the desired pitch/roll and make sure there are no oscillations in the desired pitch/roll attitude trace. the desired trace should smoothly capture the new attitude.
The other thing to be mindful of if you make this value below 0.15 seconds is whether your aircraft can even respond that quickly. You don’t want to make a request that you can’t tune your aircraft to achieve. Remember that this parameter dictates how the ghost aircraft will fly and then the attitude and rate controllers try to drive the actual aircraft to that desired attitude.


thanks to all. very detailed.

so this will also interact with ATC_ACCEL_P_MAX / ATC_ACCEL_R_MAX, right?

If this is a timing value of 0.15s (my current setting due to standard setting) in a 500series helicopter, I should increase for bigger systems from the beginning on, right?
(3.0m mainrotor diameter)

yes the ACCEL_MAX params are used to limit the requested accels.

You could ask @ChrisOlson what he does with his bigger heli’s. In my experience with full size helicopters, 0.15s is not unheard of for helicopters with stiffer rotor heads. Most RC helicopter rotor heads are pretty stiff, so I wouldn’t think that 0.15 sec rise time is out of the question. IMHO, I would keep this as low as possible as long as the helicopter can keep up. However I don’t think you need this to be much less than 0.15 seconds.

I never touch that setting since they changed it from being “RC Feel”. It affects the autopilot as well as “pilot feel” now, and doesn’t do the same thing anymore.

I use expo in the RC these days with custom curves flipped in and out with the flight mode selector switch, on both cyclic and collective, depending on which flight mode I’m in. I tune ArduPilot “hot” and then tune my custom RC curves until it handles the way I like it in each flight mode. The autopilot likes the handling “hot”. The pilot normally doesn’t.

I even have my collective curve in the RC for acro set up to apply the curve with a 0.7 second slew rate so I get seamless transition from acro to altitude modes when I switch.