About the project


The project has been started about 2 years ago in June 2007. Flying flybarless became famous around this time. In September the same year, the maiden flight took place with the first Hardware Revision.

The second Revision became available in the end of 2008. Compared to the first, the size of the Sensor- and Processing Unit has been dramatically reduced, so that it fits into smaller Helis as well.

Below you'll find some of the Hard- and Software Features:


  • Separated processing and sensor unit
  • Software-update by user
  • 3 MEMS sensors, digitally read
  • Sensorunit can be mounted 90° rotated (connectors to the side, front or rear)
  • Size processing unit ca. 54x30x20mm
  • Size sensor unit 25x25x25mm
  • Total weight ca. 40g
  • USB connection
  • Required power supply voltage from 3,5V to 9V

6 input channels:

  1. Roll or serial input
  2. Nick
  3. Pitch
  4. Tail
  5. ParSet (3 parameter sets selectable)
  6. Sensitivity (configurable for yaw and/or roll and/or nick)

6 output channels:
1-4: swashplate
5: tail
6: AUX channel (power if serial output receiver used)

Mounting in T-Rex 500

  • swashplate servos: digital or analog, triggered by 50Hz or 100Hz
  • tailservo: many popular servos selectable
  • tail servos analog or digital, triggered from 50Hz to 333Hz, various neutral impulses


Firmware features

  • 3 independent, selectable parameter sets
  • Free configurable swashplate mixer with 3 or 4 servos
  • Filter/deadband for RC and sensors
  • Freely configurable 3 axis control loops
  • I-proportion curve for roll/nick (headingHold-/rate-mode depending on pitch position)
  • Start-/stop- and left/right sensitivity for tail separately adjustable
  • Torque compensation
  • Pirouette optimization
  • Cyclic ring

PC software

  • Windows GUI
  • All setting programmable via PC software
  • Expert and beginner mode
  • Loading and saving of parameter sets
  • Tableview to diff parameter sets
  • RC/sensor data/control loop data testing
  • Firmware update

Flight logging

  • Logging of all relevant steering and control data
  • Adjustable log time and resolution
  • Control response analysis and optimization
  • Flight pattern analysis and optimization