Nonlinear robust control design of a small-scale helicopter

In this paper, we focus on the design of a nonlinear robust controller for a small-scale helicopter. A three-layer control architecture is adopted: the inner loop controller is designed combining second-order sliding mode control with extended state observer to control the angular rates and yield good robustness properties with respect to model uncertainties and gust disturbances; the middle loop controller is used to control the attitude; the...