Comprehensive nonlinear modeling of an unmanned-aerial-vehicle helicopter

Abstract

We present in this paper a comprehensive nonlinear model for our custom constructed unmanned-aerial-vehicle (UAV) helicopter. To minimize the structural complexity, the derived nonlinear model only focuses on the following four essential dynamics, including 1)kinematical dynamics; 2) rigid-body dynamics; 3) main rotor flapping dynamics and 4) factory-installed yaw rate gyro dynamics. One five-step identification method is proposed to identify the unknown parameters of the nonlinear model. Some key parameters are iteratively examined or tuned in multiple steps to ensure their accuracy. Both frequency-domain and time-domain evaluations have been conducted and the results show that the comprehensive nonlinear model is highly accurate in a wide range of flight envelope. © 2008 by the American Institute of Aeronautics and Astronautics, Inc.