Aerobatic Maneuvers of a Conventional and Compound Rotorcraft - Flight Path Generation and Dynamic Simulation

Abstract

A flight path generation algorithm was developed to calculate control inceptor commands required for a rotorcraft in complex aerobatic maneuvers. This algorithm was used to compare the performance of a conventional and compound rotorcraft in dynamic simulations and to assess performance of a dynamic inversion control law. A non-linear dynamic inversion (NLDI) based controller was developed for the conventional rotorcraft (H-60) and a compound variant. The inner loop of the H-60 NLDI controller regulates bank angle, pitch attitude, vertical speed, and yaw rate, while the outer loop commands airspeed. The inner loop of the compound H-60 NLDI controller regulates bank angle, pitch attitude, and yaw rate, while the outer loop commands longitudinal and vertical acceleration. Redundant controls on the compound rotorcraft are scheduled with airspeed and load factor to minimize power in sustained maneuvers and enhance quickness in transient flight regimes. Three aerobatic maneuvers for both the H-60 and compound H-60 are examined in simulation: Pitch-Back Turn (PBT), Combat Ascent Turn (CAT), and Combat Descent Turn (CDT). This study seeks to illustrate the following: the development and testing of tools to generate aerobatic maneuver commands to use for non-piloted simulations, the assessment of NLDI controller performance in tracking commands, and the development of an appropriate methodology for comparing the performance of a compound and conventional rotorcraft in complex maneuvers.