Thrust Vectoring Control of a Novel Tilt-Rotor UAV Based on Backstepping Sliding Model Method

Area of Science:

• Aerospace Engineering
• Control Systems
• Robotics

Background:

• Tilt-rotor UAVs with blended wing body (BWB) designs offer stealth and VTOL capabilities for reconnaissance.
• Conventional position-attitude control (CPAC) struggles with crosswind disturbances and mission interference, causing touchdown issues and compromising stability.
• BWB UAVs face challenges with high aspect ratios, leading to wingtip touchdown problems.

Purpose of the Study:

• To develop and validate a novel control method for a tilt-rotor UAV with a BWB layout.
• To address the limitations of CPAC in handling crosswind disturbances and mission-related interferences.
• To enhance landing accuracy, speed, and overall flight control during the VTOL phase.

Main Methods:

• Proposed a direct thrust vectoring control (DTVC) scheme by incorporating rotor tilt mechanism control authority.
• Designed a robust UAV controller using backstepping sliding mode control to manage nonlinearities, uncertainties, and perturbations.
• Utilized Lyapunov functions to determine control system stability and Monte Carlo simulations for statistical landing accuracy testing.

Main Results:

• The DTVC scheme significantly improved landing accuracy and speed compared to the CPAC scheme.
• DTVC successfully decoupled the position control loop from the attitude control loop.
• The proposed controller demonstrated enhanced response rate and bandwidth for flight trajectory control.

Conclusions:

• The DTVC scheme is effective for tilt-rotor UAVs with BWB configurations, especially during VTOL.
• The developed robust controller ensures stability and accuracy despite system nonlinearities and external disturbances.
• This advancement enables reliable carrier-borne reconnaissance missions with enhanced stealth and operational capabilities.