Comparison of two approaches for adaptive feedforward compensation in active vibration control with mechanical coupling

Adaptive feedforward broadband vibration (or noise) compensation is currently used when a correlated measurement with the disturbance (i.e. an image of the distrubance) is available. However, in most of the systems there is a "positive" feedback coupling between the compensator system and the measurement of the image of the disturbance. This may lead to the instability of the system. In a stable adaption algorithm for IIR compensators operating in the context of internal coupling has been proposed and evaluated experimentally. In a stable adaptation algorithm for a feedforward compensator having a Youla Kucera structure has been proposed. The objective of this paper is to comparatively evaluate the two approaches from theoretical and experimental points of view. An active vibration control system featuring an internal mechanical coupling will serve as a test bench.