Pixracer liftoff problems - can't get it to hover


After losing my q250 and good first impression on pixhawk on my hex I decided to go for something new for my new q250 and got the pixracer. After waiting for a long time it finally arrived two weeks ago, and I have problems getting it to start ever since.

First flashed it with PX4 - setup everything. It looks good on the bench - no errors from QGC. But I can not get it to fly.
So I at some point flashed copter 3.3. Also no problem reported from MP.

I do arm, and the motors do not spin, so I get the throttle higher - and at some point it suddenly shoots in the sky.

It will either fall - or go fast up. I can not get the copter to hover. It’s kind of stable (when it does not fall), but very hard to control.

I will put a log from a yesterdays flight on the field were I had more space to try to control it - with no luck, when I get back from the work.

On the PixRacer I would recommend to use the newer version of the Copter . currently 3.4RC1.

Redo the entire calibrations, including ESC’s

I had the same issue with my robocat 270 running 2206 motor, 6 inch props and 4s battery. I had to change thr_mid to 300, stabilize rate and roll to 3.5 and d term to .002 just to make it hover. It seems the default PID is not meant for overpowered quads.

I don’t know if it’s the new FW or something else but my quad flys again. But one big thing I did different this time was to plug in the safety switch during esc calibration. I have the safety switch taken of from the quad, and disabled from the parameters. I think that esc calibration still relays on it to be used during calibration, and the esc were calibrated wrong during the first try.

Now it’s time for tuning as it flys but is not to well in default settings :slight_smile: