LPV System Identification of VTOL Aircraft With Hybrid Configuration

Abstract This paper presents the modeling and system identification of a Vertical Take-Off and Landing (VTOL) aircraft with a hybrid configuration of tilt-rotors and fixed-wing. The hybrid VTOL design combines the hovering capability of multicopters with the aerodynamic efficiency of fixed-wing flight, enabling smooth transition between these flight modes. A nonlinear dynamic model is derived for the longitudinal motion with a focus on the transition phase. Using experimental flight data, unknown aerodynamic parameters are identified through a grey-box modeling approach, which employs a modified Least-Squares Regression (LSR) method that incorporates constraints to ensure physically meaningful parameter estimates. Both constant and polynomial parameter models are developed and validated, demonstrating good alignment with experimental results. This study provides valuable insights into the dynamic behavior of hybrid VTOL systems and offers a foundation for advanced control design to support the development of Urban Air Mobility (UAM) solutions.