H _∞ loop-shaping controller synthesis for a 3-DOF helicopter system

This paper investigates a robust controller solution for the position and attitude control problem of 3degree of freedom (DOF) helicopter system. The model of the elevation, roll and travel rate dynamics is considered as a single-input single-output linear system with external disturbances. The article adopts ℋ _∞ loop-shaping based robust control concept for the helicopter model to achieve desired attitude (elevation and roll angles) and position (travel rate). The robust properties of the closed-loop system are proven, and simulation results of the paper shows that robust stability and robust tracking property can be achieved simultaneously.