Autonomous control of unmanned combat air vehicles: Design of a multimodal control and flight planning framework for agile maneuvering

There is a growing demand for unmanned air vehicles (UAVs) with combat capabilities in battlefield scenarios [1]. Whether this capability is for evasive maneuvers or for flying attack patterns, unmanned combat air vehicles (UCAVs) are expected to operate in dense and often threatening environments that require aggressive trajectory planning and controls [1]. These trajectories often require the use of maneuvering capability over the full flight envelope of the aircraft. Examples of such trajectories are high-g turns and high angle-of-attack maneuvers. This article presents the development of a multimodal flight control and flight path planning scheme that allows the vehicle to autonomously perform agile maneuvers over its full flight envelope. The key element of this scheme is the maneuver decomposition methodology, which aims to reduce the complexity of the planning and control problems for UCAVs. This article demonstrates how a parameterized family of maneuver modes for a UCAV can be developed systematically and how an arbitrary agile maneuver can be decomposed into simpler segments. In addition, the article presents a multimodal flight control scheme in which each of the maneuver modes is controlled locally by a sliding mode controller. The overall capability of the system is demonstrated in challenging scenarios such as navigation in dense environments and autonomous execution of aerobatics competition sequences.