Pid tuning for 8kg quadcopter

Guys I need help. I tried everything but our drone is not stable. Our drone properties below:

  • 17 inch carbonfiber propellers
  • MN6700 320Kv motors
  • 8kg weight
  • Distance between motor and center of frame is 48cm
  • Orangecube+ board and PX4 firmware
  • H16 telemetry
  • Here3+ GNSS GPS
  • 6S LiPo battery

Does anyone know how to tune PIDs just enough to takeoff. If it can be stable, we will try autotune then. Can anybody help? WE NEED HELP

Hello, Can you elaborate “not stable”?
What kind of issue are you facing, is the drone wobbling, Is it overshooting on tx inputs?

Can you show your Vibration Analysis plots?

We were able to solve it once and it was able to take off and land, but when we tested it in the stadium, it suddenly hit the ground and started to rise again. Then we changed the PIDs and this time the two motors in front gave more thrust and pitched in the opposite direction. We tried very hard but couldn’t fix it.

I’m unconvinced this is an issue that is resolvable via PID tuning. In larger vehicles it is fairly common for vibration to saturate the IMU sensors, resulting in a bad state estimate.

It is entirely possible, if not likely, that the issue is that the vehicle has an incorrect attitude solution. The requested vibration plots would assist in analysis.