Accumulative drift

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ziss_dm
Posts: 529
Joined: Tue Mar 08, 2011 5:26 am

Re: Accumulative drift

Post by ziss_dm »

Hi Noctaro,

Can you connect GUI after flight without re-connecting power and check gyro values?
If they not 0 - problem with gyro, if not somethere else.

regards,
ziss_dm

Noctaro
Posts: 280
Joined: Thu Sep 08, 2011 11:15 am
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Re: Accumulative drift

Post by Noctaro »

hey ziss_dm,
thanks for your advise. I did a testflight, did not reconnect power and connected programmer. As i connect it, Arduino seems to reinit, so i am not sure if i would get the correct inflight data. But as far i could test it, Gyro was at constant 0(rolling and pitching worked as it should). Same with I2C errors. What else could cause a drift over time that will influence acro mode? By over time i mean, the drift starts suddenly, but everytime around 8-10 minutes of flighttime. Its predictable, it will start drifting front right. Sometimes more front sometimes more right. Intresting thing, if i roll left at 30°, it compensates nearly like in stable mode and goes nearly back to level(Rolls faster right). Then slowly starts to drift right again(Rolls slowly right). Feels a bit of a "left roll stable to right" mode :D I don´t get it. Any ideas are welcome. Feel free to ask for more infos if needed :)
greetz
noc

btw. handling the drift in acromode is not a big problem, but in stable mode its hard to compensate, as if drift occurs, new leveled positions is constant right front around 10° i guess.
The overall performance with 1.9 is impressing. I now can fly my quad through doors if i want to because its that precise inflight. Thanks to all for development!

Noctaro
Posts: 280
Joined: Thu Sep 08, 2011 11:15 am
Contact:

Re: Accumulative drift

Post by Noctaro »

Hi,
doing the gyro calibration routine when drift starts does solve it in both acro and stable mode.
But i have to do it around every 6 minutes. Is my gyro damaged?

I think i did not see the drift of gyro with my old akkus because they only supplied me for around 7 minutes of flight.
Now i got around 18 minutes of flighttime and can see acro mode drifting away again and again. Predictable to front right.
As some variable would run away and keep increasing. But maybe it is really depended to my wmc+

Noctaro
Posts: 280
Joined: Thu Sep 08, 2011 11:15 am
Contact:

Re: Accumulative drift

Post by Noctaro »

Hey,
i found out, that if i hit start in gui and then disconnect my quad without hitting stop, it will not reinitalize if i reconnect. So now i am sure i will get the correct inflight data, but gyro does not show up drift, before or after flight. (Constant 0 if not moving)
Also temperature,light and wind should not be the cause, because i also get the drift indoors.
Am i the only one who got this problem using WMP+?
Are there any other tests i could do?

please help

Noctaro
Posts: 280
Joined: Thu Sep 08, 2011 11:15 am
Contact:

Re: Accumulative drift

Post by Noctaro »

Solved a big mystery.
Replacing the WMP+ with a ITG3200-breakoutboard(defualt lpf set), did the trick. No accumulative drift in acro or level mode(BMA180). Everything working fine, tested both sensors with mw2.0pre2 (wmp+ still caused a drift).

greetz
Noc

btw. never touch your mag with a soldering iron, it may cause i2c errors afterwards. 8-)

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