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.
- 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 beta Firmware using QGroundControl - In the setup view → Advanced Parameters, set:
- SYS_AUTOSTART to 13002
- VT_TYPE to 1 (tiltrotor airframe)
- SYS_AUTOCONFIG to 1
- VT_MOT_COUNT to 6
- Click on “Set” - Click on “Write” - Reboot (power-cycle)
The system should now be ready for sensor calibration, at the end of which it should allow arming.
In QGroundControl assign a switch of your remote to channel aux1 during the RC calibration step. This allows you to switch between the multicopter- and fixed wing mode. The switch in the off-position means that you are flying in multicopter mode. 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.