Stability Analysis & Development of a Control Strategy for a Small UAV

Developing a suitable Flight Dynamics Model (FDM) by assessing the stability and controllability characteristics of the aircraft is essential during the conceptual and preliminary design phase, as it enables us to proceed with further analysis of loads endured and maneuverability aspects. In this paper, a strategy for computing the stability parameters of a Small-Scale Loitering UAV with a selected wing span employing two different stability analysis tools is presented that provides a quick approach for analyzing the stability characteristics of any UAV; this is followed by the implementation of a sizing methodology for control surface sizing; which were selected as Ailerons, and Ruddervators. Subsequently, the control integrated dynamics model is subjected to control input testing to evaluate the stability and control capabilities and later to develop suitable stabilization augmentation using state-feedback control. The results indicate only a minor discrepancy between the stability results of both the tools, with the overall aircraft being statically, and dynamically stable. Furthermore, the designed control surfaces satisfy the critical requirements and can adequately follow, and react to the input commands. This study carries a great deal of significance for the stability and especially control design engineers working in the domain of UAV design as it presents a simple method for developing a complete 6-DOF FDM