Simulation, Flight Dynamics, and Control Design for a Coaxial Rotorcraft

A 600kg helicopter drone was developed at the Technical University of Munich based on the edm aerotech GmbH CoAX 600 rotorcraft. In this work, a simulation model for the helicopter was developed and validated for control design and pilot training purposes. The simulation model consists of a physics-based model structure, developed by coupling a dynamic rotor model with a rigid body fuselage. Both the rotor aerodynamics, which utilizes the blade element momentum theory to compute the rotor forces and moments, and the fuselage aerodynamics include unknown parameters, which are estimated based on flight test data, using the Output Error Method of the Maximum-Likelihood parameter estimation method in the time domain. The proof of match for the model is provided in the time and frequency domains. The nonlinear model was linearized at hover and the linearized model was utilized for control design and stability analysis. The design and validation of the flight controller is also discussed in the paper.