A novel direct drive tail for miniature flybarless helicopters

This paper develops a novel mechanism of direct drive tails for miniature helicopters. The developed tail employs a brushless motor mode and outperforms the traditional torque tube tails with less vibration and prompter responses. Mechanism design and implementation of the direct drive tail is presented at first. A nonlinear model is adopted into analyzing the direct drive tail's influence on kinematics and dynamics of miniature helicopters. Control parameters are optimized by online testing and experience as well. Experiments with an Align T-REX 450L helicopter and a Pixhawk autopilot are conducted to validate the effectiveness of the developed new-type direct drive tail mechanism.