FUZZY LOGIC DETECTOR FOR AIRCRAFT PILOT COUPLING AND PILOT INDUCED OSCILLATION

This paper describes the design of a fuzzy logic based detector for Pilot Induced Oscillations (PIO), a form of Aircraft Pilot Coupling (APC). The fuzzy detector uses frequency and time domain fuzzy variables within a knowledge-based rule set to provide real-time detection of the onset of adverse Aircraft Pilot Coupling. Frequency domain preprocessing uses a recursive finite Fourier transform method to extract the primary frequencies and amplitudes from the control and state signals and determines the phase shift between them. Time domain preprocessing extracts the aircraft actuator speed, the saturation of which is known to exacerbate PIO. The fuzzy inference system will serve as a controllability limit predictor for PIO compensation systems, especially active tactile limit avoidance cueing systems.