Control Algorithm for Taking off and Landing Manoeuvres of Quadrotors in Open Navigation Environments

This paper presents a control algorithm for the taking off and landing manoeuvres of a quadrotor aircraft in open navigation environments. For this purpose, a combination of controllers based on nested saturations and a generalised proportional integral (GPI) controller is used. The first controller limits both the angular positions and angular velocities in a small compact set, which defines the closed-loop stability domain and guarantees the total convergence of the state, whereas the second is designed for the translational aspect, considering the presence of disturbances during landing. The proposed controller is designed considering the presence of disturbances; therefore, greater robustness is obtained regarding perturbations that may occur in open navigation environments. The algorithm convergence is proven by means of Lyapunov’s second method. Several numerical simulations are presented to demonstrate the effectiveness of our proposed algorithm, and a comparison test against an effective method for indoor environments is provided to illustrate its superior performance.