INAV 9.1.0 Pitch Attitude Estimate Off when Adjusting Waypoint Altitude

[jongell]

https://youtu.be/sr_jaVwVR_w

When the Vehicle is on it's way to the 1st waypoint it climbs just fine with max 10° Pitch up.

As soon as it enters "Adjusting Waypoint Altitude" it banks hard to keep the loiter and with 10° Pitch up starts to lose a ton of altitude. I take over in Acro.

I need help to understand if this is just normal and I can just increase the Max Pitch up by 5° and it'll be fine or if there is an actual Estimation problem here.

INAV 9.1.0 config diff is added

strobediff.txt

[breadoven]

Best way of checking if the altitude estimation is wrong is to look at the baro and GPS altitudes/rates and see if they correlate with the estimation.

[jongell]

@breadoven Thanks for the Hint! I will check. I was thinking the main issue here was the Pitch angle estimate. Could it lose a ton of altitude with 10° Up Pitch while it is banked and it is just normal? Also the Pitch Angle estimate could be off due to G forces which should be compensated from INAV 6 using GPS if I remember correctly.

[jongell]

I have another theory:

Because nav_fw_climb_angle is set to 10 (too low) during bank the constant G-Forces cause the Accelerometer Pitch to drift which causes the Vehicle not to pitch up enough to slow it down making the effect worse. If I set it to 15° it should pitch up enough to slow it down making the G-Force Effects reduced and it should not lose altitude. Let's see

[jongell]

Ok it did not help really. The Pitch Angle Estimate is very off during turns causing massive overspeed. And because Throttle is controlled via Pitch2Throttle the altitude controller does prioritize Pitch over Vertical Speed which is a problem still. I will mitigate it by increasing the loiter radius so the G-Forces are just reduced.