AltitudeHold - PID to maintain height during maneuvers
« on: August 29, 2016, 10:32:11 am »
In Attitude Flight Mode and using Altitude Hold for Thrust, I have already tuned the VerticalVelPIDs for AltitudeHoldSettings. So no oscillations and smooth altitude hold when hovering and if I move slowly with roll/pitch/yaw - all is fine on stable height. However, I am observering now the following when doing a more quick and aggressive stick push (like 45% roll):

If I start to add a quick and more high roll or pitch the quad looses height and ony very sloooowly regains the height (no oscillations anyhow). So it looks like the altitudehold functions only very slowly starts to power up to regain the height during more aggressive manoevers.

Any idea on which PID setting should be adjusted to ensure a more quick reaction to maintain/regain height from the altitude hold feature when entering more strong roll/pitch?

Re: AltitudeHold - PID to maintain height during maneuvers
« Reply #1 on: August 29, 2016, 05:06:33 pm »
Addition:

When I roll right: height decreases. A quick/fast roll left: height increases. Same with pitch: fast/quick pitch forward height decreases; fast/quick pitch backward height increases.

However, quad does stable hover and stable height when doing smooth/soft moves on roll and pitch.

f5soh

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Re: AltitudeHold - PID to maintain height during maneuvers
« Reply #2 on: August 29, 2016, 07:04:31 pm »
Is the barometer sensor protected from sunlight ?

Re: AltitudeHold - PID to maintain height during maneuvers
« Reply #3 on: August 29, 2016, 07:33:43 pm »
yes. foam + cover. normal position hold height during hovering works with stable height. height up/down only during quick/fast manoevers. It looks like it takes too long until more power is added to maintain height. It should more quickly add thrust and not wait until height drops down if a quick/fast/more agressive maneuver is started.

f5soh

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    • LibrePilot
Re: AltitudeHold - PID to maintain height during maneuvers
« Reply #4 on: August 29, 2016, 11:38:26 pm »
If you want quicker response you should increase the P term.

Try using Attitude + CruiseControl doing same maneuvers, and maybe adjust the PowerTrim value.
CruiseControl is also used with AltHold/Vario modes.