I had a very bad vibration problem with my copter, which resulted in the well known shoot up in the sky then dip problem. I now have very different and well balanced props, as well as different motors, and the vibration seem well under control.
Today I did a test flight in high winds, and I had no canopy over the pixhawk (which I generally have).
The effect was very similar to when I had bad vibration problems, not so much shooting up but still some wobbly altitude hold, going up and down by a meter or so.
Now from the log, It looks to me that the vibration are well within the given acceptable parameters (+-3 for X and Y, and -5-15 for Z.
The barometer instead sometime goes negative altitude (I was on a flat field) making me thing that that's the problem, the wind hitting the copter is messing with the barometer.
Does anybody have a second opinion? I'd like to close the incident saying it was the wind+lack of cover on the pixhawk, but given that I haven't been flying that long maybe there's something I'm overlooking.
Thanks to whoever can give my log a look.
Replies
I had similar problems with my first cuad, flies good in calm but bad in windy days, an arm was disaligned.
Do you have .log? and perhaps is usefull if you post a photo of your cuad.
I've attached the .log, I'll take a picture in a bit.
I had aligned the motor mounts to be perfectly horizontal with a bubble lever just before the flight, so no I don't think that's the problem if that's what you mean.
[EDIT] The .log is 8.1 megabytes is does not let me attach it (limit is 7MB). What program are you using that does not read the .BIN ? All the recent 3DR tools do so just fine.
the spikes aren;t included in vibrations...so the persiods between the spikes look pretty good. But that doesn't mean that unexpected spikes should be ignored. if something is tapping the flight controller it may confuse it.
If the pixhawk was uncovered it may be light and or turbulance on the barometer chip affecting altitude. the pressure changes the baro is reading is very tiny, so turbulance and local pressure affects can affect it. Not sure on pixhawk as I use APM and VR flight controllers, but those are affected by light too....probablt the same for pixhawk.
Thanks.
I thought the spikes would be actual changes in direction, but I guess a wire might be tapping the FC in some way also.
Monday I'll fly with the canopy plus there's almost no wind in the forecast. We'll see if the problem is there again.
they look too big to be manouvering, perhaps on landing you might see spikes that big but I doubt it in the air.
yeah give that a try and see how it looks.