Fuzz01

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Fixed Wing Return To Base - Setup
« on: April 16, 2017, 04:43:27 am »
Hi, I have a wing wing z 84

Setup:
Dx8
cc3d Reno Board
3dr gps
Lemon satllite

Everything is working but RTB. All green lights. My questions are -
Do I need to have GPSAssist marked in assisted controls? if I mark it and save it I get a con fig error.
So I goto the flight data screen, it tells me to set Attitude Estimation Algorithm to GPS Navigation (IN13)
BUT it already is. What am I missing? Home location is set.

are my update rates at 50hz ok?

Stabilized mode does not seem very happy either, it does work. It seems to give me enough throw on the
elevons on the ground but in the air it does not want to bank.

I have also adjusted my thrust down to 0.4 so it not on full throttle for RTH

Is somebody able to send me a file I can upload to the board? Is this possible?
« Last Edit: April 16, 2017, 04:56:42 am by Fuzz01 »

Re: Fixed Wing Return To Base - Setup
« Reply #1 on: April 16, 2017, 06:34:48 am »
Have you tried any other GPS mode, like PositionHold?

GPSAssist is only used for non-GPS modes such as Attitude (Stabilized1).

I see that you changed the min satellites from 7 to 6,  Be careful about changing these things, especially making them use poor satellite locks.

INS13 error may just be a generic error.  Remove GPSAssist from your flight modes.

Update rates of 50Hz are normal and correct for fixed wing (servos).  Except if you have digital servos.

Do you realize that Stabilized1 is Attitude mode where as soon as you release aileron it goes back to self level, so you must hold aileron for the whole turn?

Good luck!  :)

f5soh

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Re: Fixed Wing Return To Base - Setup
« Reply #2 on: April 16, 2017, 11:09:40 am »
Hi,

GPSAssist is not needed above a GPS mode. Anyways GPSAssist is only supported by Multirotors.

Seems you changed many Thrust parameters/range inside AltitudeHold/GroundPathFollower/VTOLPathFollower settings.
The only used by Wing frame is FixedWingPathFollowerSettings where you reduced the thrust between 0.1 and 0.3

You should keep default settings at first, and try to get a decent working Attitude mode stabilization.
Before using Attitude you should try Rate, check if you got oscillations and reduce PID if needed (inner loop)

For a more reactive attitude mode you should increase:
Stabilization > Settings Bank1 > Advanced > Attitude mode response
Stabilization > Settings Bank1 > Advanced > Attitude (Outer Loop)
https://librepilot.atlassian.net/wiki/display/LPDOC/Attitude+Setup#AttitudeSetup-Advancedtab

For better turns you can adjust the Vehicle > Roll diff to reduce adverse Yaw
https://en.wikipedia.org/wiki/Adverse_yaw#Differential_aileron_deflection

While flying in Attitude and you increase Throttle the wing should climb a little : Adjust Attitude > Pitch rotation.
After you got a good Attitude stabilization you can try RTB.

Be sure the Mag still without Red alarm when you apply power.