Airframe Setup – Standard Power Pack

Make sure that the propellers are installed correctly. These photos show the direction and orientation of each prop. The top motors should spin in a CCW direction while the motors at the bottom should spin in a CW direction. The ESCs come pre-soldered to the motors so the direction of rotation is fixed (counter clockwise on top and clockwise on the bottom).

 

 

 

 

The picture below shows one way of installing the Pixhawk, telemetry radio and GPS. Note that if you place the GPS on top of the power distribution board you probably should not use it as the external magnetometer.

With the above there was significant magnetic disturbances on the in-build magnetometer. If a bench test shows a drifting heading as you throttle up (props on to get enough current flowing) you may need to use the external GPS magnetometer and move it out onto the wing as shown in this photo. Of course the cabling should be improved.

Hardware Setup

  • connect the motors to the main out rail (MAIN OUT) of the Pixhawk according to the scheme seen below
  • connect the tilt-rotor servo into AUX OUT1
  • connect the two elevon servos into AUX OUT2-3
  • connect the servo cable of the landing gear into AUX OUT4

Firmware & Settings

Flash the stable firmware using QGroundControl. For the latest Tiltorotor features you will need to flash the developer firmware (master). In QGroundControl then select the airframe configuration “BirdsEyeView Aerobotics FireFly6” under “VTOL Tiltrotor” and restart.

Should the airframe not be available set the following parameters and restart:

  • SYS_AUTOSTART to 13002
  • SYS_AUTOCONFIG to 1

After the reboot the configuration values will match the Standard Power Pack. The following table serves as a guide when using the high efficiency setup.

Parameter Standard High-Efficiency
MC_PITCHRATE_FF 0.0 0.0
MC_PITCHRATE_D 0.004 0.005
MC_PITCHRATE_I 0.002 0.09
MC_PITCHRATE_P 0.14 0.125
MC_PITCH_P 7.0 6.0
MC_ROLLRATE_FF 0.0 0.0
MC_ROLLRATE_D 0.005 0.003
MC_ROLLRATE_I 0.002 0.06
MC_ROLLRATE_P 0.19 0.125
MC_ROLL_P 7.0 6.35
MC_YAW_FF 0.5 0.3
MC_YAWRATE_FF 0.0 0.0
MC_YAWRATE_D 0.0 0.0
MC_YAWRATE_I 0.02 0.0
MC_YAWRATE_P 0.22 0.35
MC_YAW_P 4.0 2.6

 

The system should now be ready for sensor calibration, at the end of which it should allow arming.

Notes:

  • Remember to assign the transition switch for switching to fixed-wing.
  • By default permanent stabilization is enabled. If you like fully manual flying in fixed-wing, set VT_FW_PERM_STAB to 0.

The first thing to do is to try out the multicopter mode and get used to the vehicle. Also the PID attitude controllers of the vehicle should be tuned via QGroundControl before you proceed.

 

© PX4 Dev Team