Flight Control Systems with Actuator Constraints for Helicopters used as Personal Aerial Vehicles

The global population growth and the subsequent increasing number of cars are the causes of traffic congestion issues that heavily affect the road network worldwide. Enhancing the urban aerial transportation would offer the possibility to alleviate the ground-based transportation in many cities.Integrating the vertical dimension into the current road network would require a new kind of vehicle, defined as Personal Aerial Vehicle (PAV), that is required to be easier to fly than any existing aircraft.Among the existing aerial vehicles, rotorcraft are the most suitable candidates for PAVs, due to their unique vertical take-off and landing capabilities. However, due to their complex dynamics and unstable behaviour, helicopters are difficult to control and require a long and hard training that make them not comparable to cars.This doctoral thesis shows the design process of a control augmentation system to transform helicopters into PAVs accounting for handling qualities and actuator constraints. The design and testing of a flight control system is the main objective of the work. Some of the important challenges to face when implementing a flight control system on a real rotorcraft are addressed throughout the manuscript. The control system requirements for future PAVs are investigated through pilot-in-the-loop experiments using high-fidelity motion simulators. The thesis proposes methods to simplify the design process of control systems with multiple requirements and extend the current criterion for the analysis of actuator limits. With these contributions, the dissertation aims not only at improving the state of the art of helicopters as future PAVs, but also at contributing to the research of flight control systems for helicopters.