Hi All,
i have been struggling with a loiter issue for and i wanted to try and get some feedback.
Im running APM 2.5 with external compass mod. (compassmot ~5%)
NEO-6 rev2 GPS
F450 frame, 900kv motors 9-10" props depending on payload.
I have had the unit since march with little problems. I also have had a few crashes from flying a bit to aggressive sometimes.
Basically the quad flies very well in stab and alt hold, but sometimes when i flick it to loiter it shoots off in a random direction. You can see this is the attached logs around 12642 and 13810. Its easy to see if you graph pitch in and pitch and see a big difference between them. And it takes off pretty quick sometimes. (faster then it should go in nav). i can save it by switching back to stab or alt hold.
If it is loitering ok, i will fly it around in loiter and after a bit it likes to wander off, but not as fast as above. i have control input but sometimes it wanders faster then the speed it will let me correct. again if i switch to stab or alt hold it it fine.
I have tried to look at the logs, but the only thing that stands out to me is right after i switch to loiter, the WPdis shoots up to 2.5m. when its working properly it floats between 0-1m.
I thought it might be related to # of sats, but doesn't seem to be. however less sats may make it worse.
My guess right now is a flacky GPS unit. I have tried mounting it iin diff spots and 3" off the main board to see if that helps, but does not seem to change the behavior. I will get another gps unit and see if that helps.
I also tried to reload the firmware and restore defaults. no change.
Thanks in advance2013-08-15%2000-15%20114.log.
Replies
You seemed to have fixed this issue, but I was experiencing this for a bit and found I left my Data logging under Bitmask on and I believe I was overloading the processor. I turned it back to default and cleared my logs and have not had a bit of an issue since.
I had similar experience with my f450. This post solved my problem :http://diydrones.com/forum/topics/apm-2-9-loiter-alt-hold-vibration...
Look at your HDOP value. It jumps around quite a bit. So during the period you mention it goes from 1.78 to 3.29. You typically want to see this consistently under 2.0. Could something be interfering with the GPS receiver?