I wanted to start a conversation around the roll and pitch of Arducopter drifting as you fly.
The reason is I just assembled new hardware and problems that weren't there before have now shown up in a bad way. Flying indoors in a 5ft space I was able to get up to 30° error in roll and around 10-15° in pitch. I was able to control it and it flew perfectly level the whole time, I just had to hold the stick into the corner of the radio. Lading and waiting corrects the issue.
What could cause this. I had been flying an older version of the IMU this whole time. This version has an analogue filter for the gyros where the new hardware has it as an option. You must solder the pads around the gyros to enable them. I was also flying with two slightly tweaked motors giving off a lot of vibration. This could affect the accels.
My question is: If you have a problem like this, what is the vibration level on your copter, and do you have the filter pads soldered?
And notice I didn't say "loss of control" or "it didn't fly stable". I had control, and it flew perfectly. It just lost it's reference to the ground and I had to compensate with the stick. Had it been worse than 45° I would have lost control.
There are three pairs of pads, each with a white outline. (look for GYRO-XY near the relay).
Jani Solders his to enable the filter. I have never flown this board until now. I will solder them to test the filters this week.
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the discussion and the the amount of responses is a big surprise to me.
i thought i was the only one having the problem ...
in 0.23 yaw causes low frequency oscilations.
will test with the pirates trunk - that code base is rock stable.
Wanted to add to this, just in case it's useful information: each time I lift off I start stable, and immediately the copter begins adding progressive drift and I need to deflect the sticks more and more to hold position. I believe but can't swear that the initial drift comes from ambient wind, but (as an example, velocity is totally made up though) if the copter begins by drifting with the wind at ~0.5 knots and I spend a few minutes holding it in position with the sticks, when I release the sticks it heads off in the same general direction at ~4 knots. At this point the copter is not level and is clearly heading in that direction because of the airframe's tilt.
If I engage GPS loiter mode just after taking off but before the drift starts to be a problem, it holds fairly well, but the drift starts again aggressively as soon as I go back to Stable mode. If there is a bunch of drift present and I engage GPS loiter mode it does not work, the just copter drifts off in the same direction in that mode as well and doesn't seem to do anything to conteract it. I've let it get 30' to 40' from the position where I engaged Loiter to see if it was planning to correct and it doesn't.
Hope some of this helps make sense of it.
ok, i soldered the pads and flew for a few minutes.
i have a normal drift because my copter is in a bad shape - perfectly for testing because i don't care about landing belly up.
i did not notice any bad behaviour - so no warning because of soldering the two pads - for those worried.
i know exactly the behaviour of bad gyro drift because i lost one copter.
up to now i did not notice a gyro drift. i need nice wind to fly - then i can tell if the gyro drift is gone because of the soldered pads.
Is their another way besides the ch7 trim (details are nowhere to be found), to adjust the acc so that tx trimming won't be used?
i was flying the latest code yesterday, and there was a noticable drift to the left, (stable mode) so i did an aileron trim and it was flying a bit better but it still drifts on roll and pitch.
filter pads are not soldered, and there is no damping on the board.. i would say there is a sight vibration detected on the imu.
I have the same issue using 2.0.23, starts off dead stable and as I fly I have to use more and more stick to keep it in place. It looks like the drift tends to start off in a random / wind-driven direction, but as it compensates for the stick the direction stays constant. Eventually, I have to land; landing for 10+ seconds seems to fix the problem.
I have a stock frame + sonar, magnetometer, and GPS, don't have the pads soldered, and don't fly with R/C trims.
"but arms and engine direction can change after a bumpy landing etc."
Dude, that's a crash :)
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