A control strategy for forming arbitrary formations of multiple autonomous helicopters

The thesis presents a leader-follower control strategy for forming arbitrary formations of multiple autonomous helicopters. A six-degree-of-freedom dynamic model is considered for the helicopters. Sliding Mode Control is employed due to its robustness to the model uncertainties and perturbations. The first version of the controller produces four inputs, the main rotor thrust, the roll and pitch moments, and the tail rotor thrust. In the second version of the controller, the rotors' aerodynamic model and the main rotor's actuation mechanism model of the helicopter are incorporated in the controller design, in which the rotor's mechanism actuation commands are considered as the controller inputs. The controllers can successfully control an autonomous helicopter such that it follows another helicopter with any specified spatial distance. The controllers perform well even in the presence of unknown bounded external disturbance, and are robust to norm bounded dynamic model parameter uncertainties. Numerical examples and simulation results are given to illustrate the effectiveness and robustness of the designed controllers.