Model Based Roll Controller Tuning and Analysis for Small UAS in Turbulent Environments

Abstract

Wind and turbulence in the atmosphere have a big impact on the performance of small UASs during missions such as remote sensing, disaster response, or meteorological measurements. The roll attitude controller is focused in this paper for the purpose of turbulence rejection investigation using a first order model, high order model, state-space model, 6-DOF model, and UAS flight analysis. System identification was successfully performed on the KHawk-55 flying wing UAS with only aileron inputs to excite the aircraft modes. Roll controller design specifications for small UAS requirements are proposed and validated in simulation including calm wind conditions and continuous turbulence. The controller performance is analyzed using user chosen frequency and time domain specifications. UAV flight test results showed the effectiveness of the proposed controller tuning approach using flight identified models.