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Users => Vehicles - Fixed Wing => Topic started by: anypis on August 17, 2018, 11:01:40 am

Title: Air speed adding to S800
Post by: anypis on August 17, 2018, 11:01:40 am
Dear all,
I finalized building a flyingwing. I want to know, anyone flew this with librepilot revo before? If yes, can you share your experience and pids?
I activated telemetry, added power module (working great), added gps, added Ibus receiver, added OSD. I also want to add pitot tube but all ports are filled :) Can I connect to servo pins?
Title: Re: Air speed adding to S800
Post by: TheOtherCliff on August 17, 2018, 11:41:21 am
Use INS13 and enable airspeedsettings.airspeedsensortype set it to groundspeedbasedwindestimation (for use without pitot)
Everything calibrated well and green health.

I think best way to tune PIDs in a fixed wing is to:
- fly manually to trim it out
- move tx trims back to center and adjust linkages instead
- repeat till it flies with trims in center
- always work toward trims in center by readjusting linkages if you must trim it in flight
- tune Rate PIDs in Rate mode to avoid oscillation at high speed
- tune Attitude PIDs in Attitude mode, mainly for decent response
- GPS modes are basically the GPS controlling Attitude mode

Play with FixedWingPathFollowerSettings.

For waypoint flight, all waypoints should have a negative error destination to ignore all the high speed or low speed errors.

Uncentered trims are a command to roll/loop slowly when you are in Rate mode.

Beware of a windup problem when switching in air from Manual to Attitude.  Work around is throttle quick to zero, switch, throttle back up.

I fly fixed wing GPS modes both with and without a pitot tube.  Pitot connected to servo pins.  Search the wiki for pitot I guess.
Title: Re: Air speed adding to S800
Post by: anypis on August 17, 2018, 11:45:43 am
Thank you TheOtherCliff for detailed and clear explanation!
I will try and share my results.