I tested autotune (build r1212-gb5890b9) on three different copters:
1. NightHawk 200 with EMax 2204 2300kv motors with Dalprop 50x45x3 props, 20A BLHeli ESC (not OneShot), 3S 1500 mAh battery, Revolution FC, weight 540g with bat.)
2. NightHawk 280 clone with RS2205 2300kv motors, GemFan 60x40x2 props, 30A BLHeli ESC (One Shot), 3S battery, Revolution FC with GPS and external mag, total weight 780 g with 4000 mAh batt.; and 700 g with 2200 mAh batt.
3. 380 quad with EMax MT2208-II 2000 kv motors with 60x40x2 props (with 70x45 props hovering was at 10% throttle), 30A BLHeli ESC, 4S battery 2650 mAh, Sparky-2 FC with GPS and external mag, total weight 960 g.
On 200 quad autotune process was smooth. Although copter is not very agile even at SmoothQuick Accessory at 100% (I set it to Accessory 1 slider). There are very minimal difference in the copter reaction between 0 and 100% slider position.
Minimal PID (smooth) Roll Pitch Yaw
P 0.00052 0.00098 0.00148
I 0.00058 0.00110 0.00134
D 0.000045 0.000085 0.000102
Max (agile) Roll Pitch Yaw
P 0.00185 0.00350 0.0042
I 0.00408 0.00773 0.00661
D 0.000080 0.000151 0.000168
Tuning of the second copter was not successful at all. With big battery (4000 mAh, 770g) it run through half of tuning process and start falling. I had to jerk throttle up to keep it flying. After two or three jerks it fall. Restart at default settings (Bank 1) was OK, it flew smooth.
With 2200 mAh batt. 700 g same copter went through autotune a bit longer but did not finish, just fell.
I have to do some more tests, I am not sure that it is autotune fault, it may be calibration or setup, or ESCs – this copter gave me headaches before too.
Third (380) copter with Sparky 2 flight controller went through autotune without any problems. Right after original assembly, it was its maiden flight (with Sparky 2).
Results were the most impressive. Big difference between smooth and agile modes. Very fast reaction without jerks and noticeable overshoots (even in most agile form). Very good feeling to fly it.
Minimal PID (smooth) Roll Pitch Yaw
P 0.00183 0.00254 0.00634
I 0.00401 0.00555 0.01209
D 0.000030 0.000041 0.000082
Stab P 4.28 4.28
I 2.248 2.248
Max (agile) Roll Pitch Yaw
P 0.00498 0.00690 0.01250
I 0.01883 0.02606 0.03238
D 0.000060 0.000083 0.000135
Stab. P = 6.695 and I = 3.516 (same for Roll and Pitch)
I am a bit surprised that in agile set derivative term is lower than in smooth mode. D, generally allow damping overshoots faster. Any way, it fly very well.
Would be happy to hear suggestions and questions.