Nonlinear Modeling and Flight Validation of a Small-Scale Compound Helicopter

The compound configuration is a good option for helicopters to break through speed limitation and improve maneuverability. However, the compound configuration applied on the small-scale helicopter has not been investigated in detail. In this study, an 11-state nonlinear dynamics model of a small-scale compound helicopter was established with the help of first physical principles and linear modification method. The ducted fan, free-rotate wing and horizontal stabilizer were considered in the compound configurations. To validate the accuracy of the model, high-quality flight data were obtained in hover and forward flights from 15 m/s to 32 m/s. Results show that the overall responses of the developed nonlinear model matched the hover data. In forward flight, it was proved that the nonlinear model has high accuracy in agreement with trim results and time-domain simulations. The wing model works well below 27 m/s. Furthermore, the effectiveness of the elevator and aileron in high speed was also verified in the simulation of a coordinated turn.

[1]  Bernard Mettler,et al.  System identification modeling of a small-scale unmanned rotorcraft for flight control design , 2002 .

[2]  J. Gordon Leishman,et al.  Principles of Helicopter Aerodynamics , 2000 .

[3]  Chen Ming,et al.  Identification of flight dynamics models of a small-scale unmanned helicopter in hover condition , 2019 .

[4]  Hyeonsoo Yeo,et al.  Design of a Slowed-Rotor Compound Helicopter for Future Joint Service Missions , 2010 .

[5]  Pablo Romero,et al.  Feasibility Study of a Novel Asymmetric Rotorcraft Configuration: Single-Rotor Advancing Blade Concept , 2013 .

[6]  Kevin Ferguson,et al.  Flight Dynamics Investigation of Compound Helicopter Configurations , 2015 .

[7]  Douglas Thomson,et al.  Maneuverability assessment of a compound helicopter configuration , 2016 .

[8]  Sepehr P. Khaligh,et al.  A System Identification Strategy for Nonlinear Model of Small-Scale Unmanned Helicopters , 2016 .

[9]  Devesh Pokhariyal,et al.  Aircraft flight dynamics with simulated ice accretion , 2001 .

[10]  Fan Yang,et al.  Nonlinear system modeling and identification of small helicopter based on genetic algorithm , 2013, Int. J. Intell. Comput. Cybern..

[11]  Subodh Bhandari,et al.  High-Order Dynamics Models of a Small UAV Helicopter Using Analytical and Parameter Identification Techniques , 2015 .

[12]  Zhiqiang Zheng,et al.  Nonlinear system identification of a small-scale unmanned helicopter , 2014 .

[13]  Mark B. Tischler,et al.  Aircraft and Rotorcraft System Identification: Engineering Methods with Flight-Test Examples , 2006 .

[14]  Sangho Kim,et al.  Configuration design and optimisation study of a compound gyroplane , 2011 .

[15]  Eric Feron,et al.  Control Logic for Automated Aerobatic Flight of a Miniature Helicopter , 2002 .

[16]  M Orchard,et al.  The fundamental configuration and design of the compound helicopter , 2003 .

[17]  Sky Sartorius.  Optimization and Design Space Visualization Applied to Early Conceptual Design of Compound Helicopters , 2011 .

[18]  Hyeonsoo Yeo,et al.  Aeromechanics Analysis of a Heavy Lift Slowed-Rotor Compound Helicopter , 2007 .

[19]  Tong Heng Lee,et al.  Comprehensive Nonlinear Modeling of an Unmanned-Aerial-Vehicle Helicopter , 2008 .

[20]  Tong Heng Lee,et al.  Unmanned Rotorcraft Systems , 2011 .

[21]  Hyeonsoo Yeo,et al.  Optimum Design of a Compound Helicopter , 2009 .

[22]  R. A. Ormiston,et al.  Revitalising advanced rotorcraft research – and the compound helicopter , 2016, The Aeronautical Journal.

[23]  Bernard Mettler,et al.  Identification Modeling and Characteristics of Miniature Rotorcraft , 2002 .

[24]  George Done,et al.  Helicopter Flight Dynamics: the Theory and Application of Flying Qualities and Simulation Modelling – Second edition G.D. Padfield Blackwell Publishing, 9600 Garsington Road, Oxford, OX4 2DQ, UK. 2007. 641pp, Illustrated. £129. ISBN 978-1-4051-1817-0. , 2009, The Aeronautical Journal (1968).