Discussions

Edit: We FLEW!!! The problem was that we didn't have the APM + IMU properly placed on the ship!! Check here for details! :) See it fly here.

About two weeks ago we had posted about a problem we were having with oscillations. Later after doing more research we realized that we had one of the Sparkfun APMs that had the fuses problem. Although we don't know how much that was contributing to our problems we thought it was worth a shot. Also we tripled checked almost everything:

• ESC calibration
• Prop types
• Prop positioning
• Motor rotation direction
• APM and IMU position on the ship
• APM and IMU vibrations (we used double sided mounting tape to attach the electronics to frame)

Also we added the DIYDrones Magnetometer, Xbee for easier tuning, a battery alarm and we burned the latest code from trunk (Beta 2 release).

Afterward we began PID tuning until we reached values where there were no oscillations and the ship seemed to respond fine to movement. At one time I was barely holding it at all and the ship was feeling pretty stable.

Here are our PID values:

pitch and roll:

P 3.5

I 0.1

D 0.5

yaw:

P 2.5

I 0.15

D 1

KP rate: 0.2

Like you can see on the video we have a problem with a motor sometimes shutting down. But we are pretty sure this is due to a bad bullet connector because after touching and moving the bullets of that motor the motor turned back on. So we will be soldering the ESCs and the Motors directly for now while some new bullet connectors and ESCs we ordered arrive.

Then we tried to take-off but we had a problem where the ship was oscillating but it wanted to go in one direction and wouldn't fly directly upwards. It would tilt itself to a side and then the props would hit the grass and they would immediately stop. Is this just a trimming problem? What are your recommendations as to where to go from here? We can post more videos if you want to see something in specific.

Any help or comments are greatly appreciated. We can't wait to see our baby fly!! :) Thanks in advance.

Another video of us attempting to fly, but it crashes :(