AutoTune unsuccessful

ArduCopter Traditional Helicopter
1

I tried my 1st AutoTune flight.
Most of the time the log shows message “AutoTune: pilot overrides active”.

I made corrections whenever the heli drifted too far away..

Was it too much ?

Log file

2

Sounds like the trims on your controller arent neutral.

edit: hmm, they are all within the deadzone of your RC channels though…

3

… except for throttle (1607 throughout the entire autotune attempt, trim 1500, deadzone 10).

(But maybe I have no idea how TradHeli works)

4

C3 is collective pitch, not throttle.
AutoTune was started in AltHold mode.
1607us is mid stick.

5

The heli autotune webpage says:

  1. Power up the controller.
  2. Set the flight mode to either stabilize or AltHold (Althold recommended).
  3. Enable motor interlock and allow rotors to complete runup.
  4. Lift off and establish stable hover approximately 3-5 meters above the ground.
  5. Switch into AutoTune and center all sticks.
  6. AutoTune will start conducting the maneuvers.

Point 5 says “center all sticks”. More precisely, the code common to both helis and multirotors uses the following predicate to determine whether pilot override is active:

if (!zero_rp_input || !is_zero(desired_yaw_rate_rads) || !is_zero(target_climb_rate_ms)) {
   ...
}

that is, the target climb rate should be zero. This goes all the way to Copter::get_pilot_desired_climb_rate_ms(), which uses variable channel_throttle for the source value, get_throttle_mid for the middle value, and THR_DZ for the deadzone. (Yes, this controls collective pitch further down the chain in Heli. The code is slightly convoluted because of the toy mode, but I guess you are not using it).

Your RC3_TRIM is 1500, and your THR_DZ is 100. So, 1607 is just a notch higher than 1600 which is the upper bound for what the system considers “mid stick”. A bit of bad luck, if you wish.

6

Yeah, that makes sense.
I will try again tomorrow paying attention to a centered collective stick.
Thank you very much!

7

I have just repeated the AutoTune flight and successfully completed it.
This time, I made sure to keep the collective stick centered.
5 flights to follow…

Log file