BAI personnel presented two papers at the recent American Helicopter Society Annual Forum, the world’s leading rotary-wing technical conference. The first paper highlighted system identification of a small-scale helicopter and quadrotor UAV using the AUSPEX tool. AUSPEX is a system identification and simulation-update tool developed by Barron Associates. Flight test data were used to identify the coefficients and model structure of the vehicles. The excellent model fits exemplify the applicability of this tool to rotary-wing aircraft. The identified dynamic models are used in additional algorithms to estimate turbulence common in rotary-wing shipboard operations.
The second paper presented results of Barron Associates flight controller research to increase pilot safety and the operational envelope of rotorcraft in Degraded Visual Environments (DVE) using advanced control methods based on Receding Horizon Optimal (RHO) control. To demonstrate the controller’s performance, simulation studies using an EH-60L rotorcraft were conducted for a number of maneuvers and Mission Task Elements. The maneuvers were performed with nominal and slung-load vehicle configurations to exemplify the robustness of the controller. A mathematical pilot model was included in the simulation framework to assess preliminary pilot workload and pilot-induced-oscillations. Pilot workload and input power were evaluated with a novel technique using scalograms, a wavelet-based metric. The RHO controller was benchmarked against a baseline controller. The results show decreased pilot workload with the RHO controller and the efficacy of the RHO formulation validates its candidacy as a desirable rotorcraft control architecture.