Path Tracking of a UAV via an Underactuated Control Strategy

In this study, a nonlinear robust control strategy designed for underactuated mechanical systems is proposed in order to solve the path tracking problem for a quadrotor unmanned aerial vehicle. An underactuated nonlinear controller based on the six degrees of freedom dynamic model is designed to control the helicopter attitude and altitude in the inner-loop. The outer-loop control is performed using a model-based predictive controller (MPC) to track the reference trajectory. The robust performance achieved with the proposed control strategy is checked by simulation in the presence of aerodynamic disturbances, unmodelled dynamics and parametric uncertainties.