Hi all. I posted this in the wrong forum yesterday, so I just edited it to post it to the 3.x forum. I am hoping someone can help me out. I appreciate any help that you can provide. My quadcopter flies fine except for the issue noted below. The problem I have is when I start autotune, everything goes fine until usually a minute or two in. The quad then pitches or rolls as it normally does in autotune but it doesn't come back to horizontal and just takes off full throttle holding the pitch or roll autotune had the quad perform. I have been lucky to recover from all of these unexpected maneuvers. There was one time that the quad did this and flew a good 50 yards away before I was able to get control again. I just don't know what is wrong with it. I have never been able to complete an autotune. It always fails after one of these maneuvers. I was reading that there are a few things that can cause an autotune to fail. One is flexible arms on the quad. I tested mine and they do flex a bit, but I am not sure if it would be enough or even the reason the quad does this in autotune. The specs for my quad are listed below.
In stabilize, the quad flies great except when I initiate an oscillation by moving the pitch/roll stick back and forth. The quad then goes into an oscillation that is almost unrecoverable. The only way I can recover from it is if I lower the throttle and gently increase it. If I give it more throttle or adjust throttle to keep the same altitude, the quad will most likely crash. I tried re-tuning the quad but it does the same thing.
I have completed several planned missions with the quad. I wanted to complete an autotune before putting my camera gimbal on the quad. I am uneasy about putting it on because of the oscillations that can be induced and potentially causing a crash.
My son took a video of the problem but he's only 5 so the video isn't all that great and didn't capture the problem the second time it happened. You will see the quad take off to the left during auto tune but I recover quickly in the video.
Hobbyking AQ-600 frame
Sunnysky X2216 1100KV motors
Turnigy Plush 30A ESC's
APM 2.5 with external compass
3DR uBlox GPS with compass
Arducopter firmware version 3.1.5
5000mAh 3S battery