• Stabilize Roll/Pitch P controls the responsiveness of the copter’s roll and pitch to pilot input and errors between the desired and actual roll and pitch angles.  The default of 4.5 will command a 4.5deg/sec rotation rate for each 1 degree of error in the angle.
  • The higher the P the faster the copter will be asked to turn to get to the desired angle.
  • A high P will cause the copter to oscillate back and forth like a seesaw a few times a second.
  • A low P will cause the copter to move very slowly. A very low P will cause the copter to feel unresponsive and could cause a crash if the wind disturbs it.
• Rate Roll/Pitch P, I and D terms control the output to the motors based on the desired rotation rate from the upper Stabilize (i.e. angular) controller.  These terms are generally related to the power-to-weight ratio of the copter with more powerful copters requiring lower rate PID values.  For example a copter that accelerates very quickly might have Rate Roll/Pitch P number of 0.08 while a more sluggish copter might use 0.18.
  • Rate Roll/Pitch P is the single most important value to tune correctly for your copter.
  • The higher the P the higher the motor response to achieve the desired turn rate.
  • Default is P = 0.15 for standard Arducopter.
  • Rate Roll/Pitch I is used to compensate for outside forces that would make your copter not maintain the desired rate for a longer period of time
  • A high I term will ramp quickly to hold the desired rate, and will ramp down quickly to avoid overshoot.
  • Rate Roll/Pitch D is used to dampen the response of the copter to accelerations toward the desired set point.
  • A high D can cause very unusual vibrations and a “memory” effect where the controls feel like they are slow or unresponsive.
  • Values as low as 0.001 and as high as .02 have all been used depending upon the vehicle