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Detection and Estimation of Helicopters Vibrations by Adaptive Notch Filters

This paper addresses online vibration detection in helicopters using Adaptive Filters. Adaptive Notch Filters (ANF) are used to estimate and track the time varying frequencies of the vibrations. We estimate and track the amplitudes and phases of time varying frequencies of the vibrations. This allows the detection of abnormal oscillations in the helicopter flight to keep control of the aircraft. In the application presented, we show the detection of severe vibrations that occurred during a helicopter flight test. This proves the effectiveness of proposed ANF to track and reject narrow band perturbations.