Innovative Rotorcraft Control for Shipboard Operations

A prototype adaptive flight control concept was developed in Phase I which better compensates for dis-turbances on the rotorcraft due to ship airwake effects and the moving ship deck during helicopter or tiltrotor shipboard operations. It is proposed to further mature the algorithms associated with this control approach in a limited-scope Phase II program. A parameter identification algorithm and an on-line learning approach will be further matured to deliver in-flight estimates of important effects of the ship airwake and ship motion. The system identifies both the statistical properties of the apparently random characteristics of the airwake as well as the repeatable and deterministic disturbances of the airwake due to the ship’s geometry and motion. The Phase I flight controller was designed to use the information from the on-line identification/learning algorithms to improve disturbance rejection properties of the aircraft. The system provides enhanced feedback compensation to improve rejection of disturbances due to random airwake forces impinging on the vehicle, and feed-forward compensation to help compensate for deterministic airwake disturbances. We will focus application on a tilt-rotor UAV model. However, the flight controller could also be applied to manned rotorcraft.