I have been playing around with my Arducopter for a month or two now and it has been performing well. However, since last week it has started yawing like crazy. It tilts while taking off and then starts spinning rapidly in the air. I have flied with and without SIMPLE in the STABILIZE mode. Here are the steps I have taken:
1) Tried Firmwares 2.3 and 2.5.3
2) Erased EEPROM, reset the board
3) Leveled the quad multiple times.
4) Calibrated the compass using the new Mission Planner with Live Data as well as with a tlog.
5) Ensured the power board is connected to the right ESCs and the right motors
6) Checked motors directions are correct
7) Motors are mounted securely and vertically on the arm
8) Made sure the center of mass is almost dead center
I am using the standard 3DR quadrotor frame. I initially suspected the magnetometer (compass) as the issue. However when I disable the compass and fly without SIMPLE it continues to yaw.
Any help would be greatly appreciated. I am losing my head over this issue.
I have same issue right now. Seems like tried everything, but it's still yawing like crazy. Did you eventually solve your problem?
If you disable the compass, it's been mentioned to disconnect GPS. Run the CLI compass test as Chris mentioned--let it run for a few minutes--I had periodic "not healthy" values reported over time on another unit. Do a wiggle test on the compass solder joints. Make sure the compass gets 4.9V or more. That other unit I had reported 4.81V and the compass normally failed over time(e.g. not healthy reports)--moved the compass to a new oil pan with the right volts and viola--compass was fine.
If you have wireless telemetry, run mission planner and generate a tlog. Observe the red and black lines. Red should follow the compass (e.g. front of the APM), black should show you the direction of your vehicle (GPS vector). In my case, the black line followed the yawing, but red held--looks like a compass issue.
If the CLI tests show nothing it's likely in-flight interference from your xbee (if you have) or battery cables. Try moving your GPS antenna, xbee or batt leads.
Hmmm. interesting. I just finished building a custom frame hexa last week, flew fine on Fri & Sat. But today was another story--same issue of yaw drift!... to the point I almost crashed in a parking lot as well as a railroad track--I was in auto and it just "spun away". I was able to go into stab mode and "circle" it back. Thank god we can fly upto 400ft!
Sounds like a hardware issue. Have you checked your sensors in the CLI test suite?