Modern control theory for designing lateral autopilot systems of UAV

This paper addresses the L₁-optimization concept advanced in the modern control theory with an application to the design of the L₁-optimal lateral autopilot system. The control objective is to maintain the desired roll orientation of an UAV in the presence of external unmeasurable disturbances, in particular, of a gust. To achieve a high performance index, the two separate control algorithms are proposed. The first algorithm is designed in order to implement the L₁-optimal PI control for the stabilization of a given roll velocity. The second algorithm ensures the L₁-optimal P control necessary to stabilize the roll of the aircraft. Simulation results are given to demonstrate the properties of the proposed control method.