Multi-rotor robust trajectory tracking

This paper develops a position control strategy of a multi-rotor system, which moves from an X-Y way-point to another at constant maximum-achievable velocity, and follows rectilinear trajectories between way-points with slight deviations during transients. In achieving this, 2D-spatial displacement breaks down in time domain ramp tracking on each axis through a trajectory generation block. Then, both axis set-points are driven to model matching feedback control structures that compute the roll and pitch angles commands. Main feedback control challenges are addressing a large model uncertainty identified for the inner attitude-controlled multi-copter, and a small control-bandwidth due to angle-saturation and due to processor sample-time. In this framework the Quantitative Feedback Theory has succeed in the robust design of feedback and feed-forward control elements. Some final tests demonstrate the expected spatial and time domain performances.