Autotune suggestions

Hi

Tomorrow morning i am going to do autotune on my f450 quadcopter. i have read the wiki and followed all steps and the drone is quite well flyable with the default tune. Now, my drone is underpowered on 3s lipo, hovers around 1560us, which is on the higher side. the quadcopter has 920kv motors with 9.4x5.0 propellers.

  • Strong wind
  • High levels of gyro noise
  • Non-linear ESC response caused by the incorrect value of
    MOT_THST_EXPO
  • Flexible frame or payload mount
  • Overly flexible vibration isolation mount
  • Very low setting for MOT_SPIN_MIN
  • Overloaded propellers or motors

The wiki mentions the above as issues, and I dont think any of these is a big issue, except slight flexiblity of f450 (its not those extreme cheap, sort of a modified version with “better” materials). Now, if it crashes, its gonna be a good expense (atleast for me) so I need to avoid crash in this process. So, what would be the safest value of agressiveness parameter to get tune close to final pids, but also not too aggressive to cause crash. Also, any other suggestions/experiences are welcome.

Thanks

…

Default.

I read that some people had crashes with that so thats why asked

Lot’s of things have happened to “some people”. Default is not that aggressive. Recommendation used to be 0.1, and it was the default, which is what I use when I run Auto Tune. Too low of an aggressiveness can result in a slug of a tune.

The last time I ran Auto Tune was on V4.7-beta and I used the new AUTOTUNE_GMBK parameter at 10%. Seemed to work out OK with an aggressiveness of 0.1

ok. thanks for the help. so i will try autotune with default aggressiveness and will share the log here for further fine tuning and review, since I might judge performance incorrectly

It is extremely important to do a good job before attempting an autotune.

AMC tells you exactly step-by-step how to do that. I’m not going to repeat the entire process here. But I’m going to ask you, have correctly done all the steps before autotune?

2 Likes

yes, I have followed the wiki, and little exploration in the edit param on disk feature of amc.

Initial mandatory configuration done ?

How good are the notch filters? All post filter below -50dB?

Did you di a QuickTime to speed up autotune?

Did you do the flight with FF = 0 ? , what were the results?

mandatory configuration done - quad already flies quite well in loiter, smart_rtl, stabilize, althold.

Notch filters are good and in other post you had suggested only.

Pixhawk 2.4.8 issues (no Quiktune)

this was not done as defaults were doing quite well. If needed, I can share log and video from camera of current tune flights in althold.

Do the FF 0 flight.