Discussions

I started into quads last year with Quanum Nova. aka Cheerson CX20. While I enjoyed a few flights, I also had times where I was not in control and ultimately the beast flew off on its own and I just let it go. I did learn the basics during this somewhat brief ownership and I think I know what to expect of a quad can and should do. So I started off this spring on building a new quad based on all the new features of Arducopter, especially the EKF and redundant GPS etc. that should make it a safer and more reliable flyer.

My equipment:

• RCTimer Spider
• RCTimer 2212 920KV motors
• RCTimer 30A NFS SimonK ESCs
• Fixhawk
• Lemon Rx DSMX PPM 8-Ch Receiver +  Satellite with Failsafe
• Spektrum DX7 transmitter

I have it all together and at first loaded with Arducopter 3.2.1. using the default PIDs of 3DR_QUAD_X4_RTF. I have gone through all the calibrations such as Accelerometer, Radio, Compass, and ESCs. With my problem, I have upgraded to the latest Beta but experience the same conditions. I have been playing around with this for 3 weeks without much progress and can't find the solution on the web that would fit my problem.

When I arm the quad, the motors start up at low speed (MOT_SPIN_ARMED = 50). All motors spin at equal speed. In Motor Test of Mission Planner, all motors respond at throttle setting of 8% and each motor runs correctly according to A=1 B=4 C=2 and D=4. So everything appears to be correct at this point.

When I arm and then tweak in a little throttle the motors immediately run at different speeds. The motors on the left turn quickly (3 & 2) and the right side (1 & 4) is either off or very slow. Holding the quad in my hand and tilting it to the right slows the left motors down and the rights pick up a bit. With about a 30 degree rotation, it seems to be happy. If I tilt more to the right, it will fight my movements. If I tilt it towards level, it will again fight to get back to the 30 degrees right. Tilting forward and rear also fights against the movement and  I sense that the quad is happier with a little forward tilt too.

The Flight Data display shows level when the quad is level and tilts right, left, up and down as expected. I think that means the sensors are operating correctly but the quad isn't in sync with level.

I don't know where to proceed from here. It could be bad hardware or it could be a PID that is out of wack. I would love to get it to the point where I could fly in Stabilized and then AutoTune.

Help!