ernstock

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Yaw acro+
« on: January 20, 2017, 10:41:06 pm »
Hi
Has anyone any comment on /experience of using acro+ on yaw ?

Re: Yaw acro+
« Reply #1 on: January 21, 2017, 05:40:17 am »
If you try it, mount the FC accel chip on the center of rotation or don't use any self leveling mode for roll / pitch.

Mount everything very firmly.  The first thing to fly off when it spins fast will be the battery.

Probably not good with INS13 / GPS flight modes like VelocityRoam.

If you have problems that it tries to spin up too fast and some props almost stop, reduce your Yaw PID 'P' value down fairly low so that it takes longer to spin up to full speed.

Did you know that you can use normal Rate or AxisLock and just increase the rotation rate up to 2000 degrees per second?  Better to keep it lower than that, maybe 1800 max.  1800 is 5 revolutions per second.  You want to go faster than that?

ernstock

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Re: Yaw acro+
« Reply #2 on: January 21, 2017, 09:47:03 pm »
Thanks.
As per your last para , I was wondering what the difference would be between higher yaw rate or some acro+.
Or maybe I was also wondering : ' acro+ on yaw .... why ? '
Am happy with acro+ (at 55) on roll and pitch - it does give much snappier rolls and flips .
Just can't get my head round it's effects / reasons on yaw.
Having said as much , tried it today and it poss helped alleviate the wobble-on-hard-180-turn that I suffer with.
Mind you I've persuaded myself that I've found the cure for that before.

Re: Yaw acro+
« Reply #3 on: January 22, 2017, 07:04:24 pm »
Thanks.
As per your last para , I was wondering what the difference would be between higher yaw rate or some acro+.
Or maybe I was also wondering : ' acro+ on yaw .... why ? '
Am happy with acro+ (at 55) on roll and pitch - it does give much snappier rolls and flips .
Just can't get my head round it's effects / reasons on yaw.
Having said as much , tried it today and it poss helped alleviate the wobble-on-hard-180-turn that I suffer with.
Mind you I've persuaded myself that I've found the cure for that before.

I can believe that.  Rate / AxisLock tries hard to obey the commands you give it.  If you move the stick quickly from 0 to 1000 degrees per second, it will try hard to do that, and currently yaw command/stabilization is equal to roll/pitch command/stabilization, so when it can't jump instantly from 0 to 1000 degrees per second yaw, everything suffers.

The correct solution is to drastically reduce yaw PID so that it spins yaw up/down more slowly.  Before you do this, you should understand that this will make yaw react more slowly.  A quick motion on the yaw stick will act like you moved the stick slowly.  I haven't tried this, but I would drastically reduce yaw PID P and perhaps I too.  Maybe cut P in half to start with, then if it needs more, cut both P (again) and I in half.  Repeat cutting P and I in half till it works as desired.  If cutting in half (multiply by 0.5) is too much of a cut, try multiplying by something between 0.5 (in half) and 1.0 (no change).

I think that our command and stabilization should prioritize roll and pitch first, but that can cause other issues...

ernstock

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Re: Yaw acro+
« Reply #4 on: January 22, 2017, 08:52:32 pm »
Thank you for taking the time to give such valuable advice. Will give the yaw pids a tweek.
Will report findings here.

Have previously enabled default tps which seemed to help the fast-yaw-wobble issue a bit .

ernstock

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Re: Yaw acro+
« Reply #5 on: March 12, 2017, 10:44:18 am »
Reducing yaw P has helped , thank you.
Part of trying to fine tune the issue ( wobble , possibly in roll axis , experienced on fast 180 turns) is the difficulty in exactly re-creating the actions that cause it.
Some of it seems to be caused by fpv cam shaking - if I make sure the cam is 'tight' then it's harder to re-create the issue.
Poss it is entirely prop wash ?
Anyways , still awesome control system.
( am still sort of wondering about - " acro+ on yaw ..... why ? " )