Design and experimental verifications of the high-speed turn flight control of single-rotor helicopters by the combination of the backstepping method and optimal servo system

Abstract

Aiming at the realization of agile autonomous flight for the extension of the flying range of single-rotor helicopters in the limited flight time, the flight control system design and the control performance verification for the high-speed turn flight are conducted. To achieve the reference following control for large attitude angles and the rotor thrust, the control system is composed of the main-rotor thrust and body torque centralized controller based on the MIMO (Multiple-Input, Multiple-Output) helicopter model including the blade motion dynamics, rotor speed proportional-integral controller, the attitude controller designed via the backstepping method based on the quaternion attitude model, and the guidance controller based on translational motion model. Simulation results show that the hovering and 10-m/s straight cruise flight followed by over 45-degree bank turn is feasible by using the proposed control system. In addition, flight tests have been conducted using the experimental small unmanned electric helicopter equipped with the flight control computer, and the high speed turn agile autonomous flight was successful in the real environment.

Keywords

• helicopter
• unmanned aerial vehicle
• agile flight
• thrust control
• backstepping
• optimal servo system