Build: Convergence Tiltrotor (Pixfalcon)

The E-Flite Convergence can easily be converted to a fully autonomous VTOL with PX4. There is not much space but it's enough for a Pixfalcon flight controller with GPS and telemetry.

The original Horizon Hobby E-Flite Convergence frame and Pixfalcon have been discontinued. Alternatives are provided in the Purchase section.

Purchase

Vehicle frame options:

• WL Tech XK X450 - Banggood, AliExpress

• JJRC M02 - Banggood (AU), AliExpress

Flight controller options ():

• Pixhawk 4 Mini

• Holybro Pixhawk Mini.

• Any other compatible flight controller with small enough form-factor.

Hardware Setup

The vehicle needs 7 PWM signals, which must be connected to the flight controller outputs as specified in Airframe Reference > VTOL Tiltrotor > E-flite Convergence. This mapping is reproduced below.

Port	Connection
MAIN 1	Motor right
MAIN 2	Motor left
MAIN 3	Motor back
MAIN 4	empty
MAIN 5	Tilt servo right
MAIN 6	Tilt servo left
MAIN 7	Elevon right
MAIN 8	Elevon left

Note that left and right in the reference are defined from the perspective of a human pilot inside a real plane (or looking from above, as shown below):

Flight Controller

The flight controller can be mounted at the same place the original autopilot was.

Telemetry Radio

The telemetry module fits into the bay meant to hold FPV transmission gear.

GPS

For the GPS we cut out a section of foam inside the "cockpit". That way the GPS can be put inside the body and is nicely stowed away without compromising the vehicle appearance.

PX4 Configuration

Follow the Standard Configuration in QGroundControl (radio, sensors, flight modes, etc.).

The particular settings that are relevant to this vehicle are:

• Airframe
• Flight Modes/Switches

  • As this is a VTOL vehicle, you must assign an RC controller switch for transitioning between multicopter and fixed-wing modes.

By default permanent stabilization is enabled. To fly "fully manual" in fixed-wing mode, set VT_FW_PERM_STAB to 0.