Design of a digital controller for a rotary wing comprehensive flight simulator

The thesis work has been partially developed at the Centre for Aviation (ZAV) of the Zurich University of Applied Sciences (ZHAW) where a flight simulator called ReDSim is available for research and didactics purposes. A control loading system (CLS) purchased by the ZAV from an external company is the component on which the work focuses on. Control loading systems are fundamentals in flight simulation since they are connected to the aircraft control members and provide the force feedback to the pilot’s actions. A model-based approach is used to drive the CLS, on which a collective lever-like grip is mounted. A MATLAB/Simulink model is developed to implement the features of a collective lever and make the system respond realistically when operated. A C++ project already written at the ZAV has been modified, the project is inserted in a MATLAB S-function responsible for data and commands exchange between the adopted CLS and the MATLAB/Simulink model. The model has been integrated with the model of the aircraft, a tiltrotor, in the software environment of the ReDSim, which is MATLAB/Simulink. Modelling and experimental activity have been carried out to estimate the relevant parameters of the system such as friction and damping, to perform gravity compensation, to provide force and position gearings for unit measurement transformations, to tune the system characteristics thanks to the control loading system’s settings and control loop parameters that can be changed from the communication software. The CLS parameters tuning has been performed after an insight into Permanent Magnet Synchronous Motor control with Field Oriented Control technique, which gives the theoretical foundations to the control schemes of the adopted CLS. Several simulations of flight manoeuvres have been performed in the ReDSim by a pilot, so that the correctness of the implementation is tested. Some features of the MATLAB/Simulink model have been changed during the pilot-in-the-loop simulations according to the pilot’s indications.