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Arifian, Kenneth C.

Publications and source records attributed to Arifian, Kenneth C..

Emergency Control for a Circulation-Control Helicopter Rotor

Digital system gives pilot partial command when primary system fails. Emergency system provides digital control of rigid circulation-control rotor for experimental X-wing aircraft. In addition to centering collective-pitch control, new command provides limited roll control via collective pitch and gyroscopic decoupling in pitch and aerodynamic decoupling.

Fischer, William C.↗

Redundant control system for X-wing valve actuators

The capability of compensating automatically for a failure in an actuator and the associated drive circuit is enhanced by providing a dual channel actuator, each channel having a drive coil and a position sensor tracking the position of the actuator output shaft. A separate circuit is provided for each actuator channel to detect drive loop failures and hydraulic failures. When the drive loop of one channel fails, it is disengaged, and the gain in the remaining drive loop is doubled to maintain authority. In an embodiment, the remaining drive loop cannot disengage when certain criteria, relating to the failure of associated actuators, are met. The invention is particularly useful for aerospace applications.

Arifian, Kenneth C.↗