Motor clipping when using vertical altitude override

[HeliHenkie]

Hi all,

Don't know for sure if it's a Quatos problem, but the problem does not appear when using PID control. I've been looking into a problem I have when changing altitude in alt/pos hold (vertical altitude override).
When I change altitude very slowly motor output appears to be normal, but when I try to change altitude fast my motor output clips. You can hear it very well. When analyzing the data you can see that even when motor output is not clipping there are little spikes on the motor ouput signal with a periodicity of 0.2 s (every 40 measurements at 200 hz).

Has anybody seens this before? Is there something I can do about it?

I'm running an AQ 6 board (latest revision), with DIMU 1.1, KISS esc's and a special firmware version compiled by Menno to enable using Quatos. My quad weighs around 770 gr.

Three pictures showing the problem are attached.

Best regards,

Jan Willem
The Neherlands

[chschmid]

Hi Jan Willem

Did you solve this? Could you share your findings?

Cheers
Christof

[HeliHenkie]

[LPR]

Jan

I had the same problem with my 4.5 Kg quadcopter while using Quatos. The motors were completely saturated to the point it caused a crash when the quad was trying to change altitude too quickly in APH or in a mission. I solved the crashing by increasing the QUATOS_MAX_OUT from 4 to 10.

I still had the very aggressive altitude changes and some motor saturation. After reading how the altitude NAV_SPEED_P and NAV_SPEED_I worked, I changed the settings.

For my quad I set NAV_ALT_SPED_P at 100 and NAV_ALT_SPED_I at .6 and that smoothed out the altitude control.

The quad flies very well now. Here's a video of the quad flying a 15 m/s mission.

https://www.youtube.com/watch?v=MT9kfbeb9Cw

Larry

[chschmid]

[aBUGSworstnightmare]

[LPR]

Joerg

There's not anything special about the Quatos parameters except the Quatos_max_out. Larger MRs may need to have a higher value for Max out.

After I lowered the Max amps setting in the ESC32 V3 from 26 to 20 I had control problems when doing aggressive flying. Increasing Quatos Max out gave me much more aggressive control for yaw and tilt.

The trick to making the fast cornering is to set the ROI for the WPs very high. I used 18 meters for the mission in the video.

QUATOS_AM1 -4
QUATOS_AM1_KNOB 0
QUATOS_AM2 -9
QUATOS_AM2_KNOB 0
QUATOS_J_PITCH 0.230733007193
QUATOS_J_ROLL 0.109981000423
QUATOS_J_YAW 0.333047002554
QUATOS_K1_KNOB 0
QUATOS_L1_ASP -10
QUATOS_L1_K1 11
QUATOS_MAX_OUT 10
QUATOS_MM_P01 0.24748699367
QUATOS_MM_P02 0.24748699367
QUATOS_MM_P03 -0.24748699367
QUATOS_MM_P04 -0.24748699367

QUATOS_MM_Y16 0
QUATOS_M_TLT_RT 1
QUATOS_M_YAW_RT 1
QUATOS_PROP_K1 4.5
QUATOS_PT_KNOB 0
QUATOS_QUAT_TAU 0.0500000007451

Larry