Trajectory Tracking for Tilted Hexarotors with Concurrent Attitude Regulation

Focusing on tilted hexarotors, we propose two control architectures that can tackle the position trajectory tracking task, ensuring also the attitude regulation. One is designed resting on the differential flatness property of the system, overcoming the standard implementation for under-actuated multi-rotors, and the other is a hierarchical nonlinear controller, building upon an advanced state-of-art hovering regulator. We comparatively discuss the performance of the two control schemes, in terms of the accuracy of both the tracking control action and the attitude regulation, the actuators effort, and the robustness in windy flight conditions. Numerical results reveal both the robustness of the hierarchical approach in the presence of external disturbances and the accuracy of the differential flatness-based controller in ideal flight scenarios.