Hexacopter Issues with taking off

Pixhawk
1

Hello everybody,

i have never posted to a forum before, but I’m totally lost.

There are some weird behaviors that I can not explain:

So on my first flight after upgrading to new motors, I was able to takeoff with my hexacopter. The drone was wobbly but flew. I switched to Position Mode and the drone was shaking and crashing.

So I figured to look at the PID Values in QGC. I changed the P-Value, but then the drone was not able to take off anymore. So I changed the values back to default. But the drone was not able to takeoff again.

So I reseted everything. I was able to fly again. But after landing and reconnecting the battery, suddenly only one motor was spinning according to the RC Throttle Input. The others were spinning with the default “arming” speed, they were also not responding to roll or pitch inputs.

After reconnecting the battery and trying to arm, it said that the accel Cal is inconsistent.

Im not sure of how all different errors are connected.

If it helps, here are some infos about my hexacopter:

  • Gartt 400kv Motors with 15.5 Props
  • 30A Racerstar Esc
  • Pixhawk 2.4.8
  • Custom frame

I would really appreciate any help! After many days of testing and putting props off and on again, I don’t know what to do.

Best regards,
Cornelius

2

It’s hard to say what is wrong given you did multiple tries and you are listing various issues that are not necessarily related to each other.

I generally would suggest to:

  1. Reset airframe in QGC which resets all params.
  2. Make sure all ESCs are working correctly and properly calibrated.
  3. Make sure RC is calibrated and working correctly.
  4. Do a short flight in Stabilized or altitude control to get a log file and then upload that logfile to logs.px4.io and paste the link here.

Then we can give feedback on that one flight and go from there.

3

I tried to takeoff several times now and realized several things.

When I connect a full battery, the drone is able to takeoff, but flies very wobbly(I guess I need to do some PID Tuning)
The drone is only able to fly one time. Once I land, the drone is not taking off again.
Only one motor is spinning and reacting to input controls. The others are spinning at around the same speed. In QGC the RC Inputs are displayed correct.
The log folder for the recent flights is empty. (and very old ones are corrupt) I will try to get a log file.

So when I then connect a new fully loaded battery, the drone is taking off again. But only once.

I already checked the esc calibration and reset the pixhawk.

So the battery is somewhat related, but I dont understand why the drone is not working with 90% Battery left.

4

Please share a log, otherwise we can’t really help. If no logs show up, try reformatting the SD card (FAT32) or use another card.