Inverse Simulation of Autogyros

Abstract

The high fatality rate of autogyros in the 1990s sparked academic research into autogyro performance, stability and control, and handling qualities. This has included limited study on the inverse simulation of autogyros. The conducted research relied on the use of a modified version of the Generic Inverse Simulation Algorithm (GENISA), which used an iteratively recalculated inverse simulation time step to account for the variability in rotor speed throughout maneuvers. This does not allow for prediction of maneuver completion time, though, significantly increasing computational workload when developing ADS-33E mission task element maneuver models. The research conducted in this article presents a further modified inverse simulation algorithm, based on GENISA, which allows a constant inverse simulation time step to be utilized. Robustness analysis of the inverse simulation algorithm, using a mathematical model of the longitudinal dynamics of a two-seat Montgomerie–Parsons autogyro, showed it is robust enough to analyze realistic medium (60 mph) and high-speed (80 mph) longitudinal pop-up and pop-down maneuvers. More importantly, the constant time step in the algorithm allows for prediction of maneuver completion time, significantly reducing workload when conducting handling qualities assessment.