Hybrid adaptive feedforward-feedback compensation algorithms for active vibration control systems

The paper adresses the problem of simultaneous adaptive feedforward compensation and feedback compensation of vibrations (or noise) when a correlated measurement with the disturbance (an image of the disturbance) is available. The study is carried in the presence of a “positive” mechanical coupling between the compensator system and the measurement of the image of the disturbance, which often occurs in practice. The positive mechanical coupling introduces a coupling between the design of the feedback loop and the stability conditions for the adaptive feedforward compensation. Modifications of the algorithms for adaptive feedforward compensation has to be considered. The new algorithms proposed are analyzed and have been applied to an active vibration control system featuring internal positive mechanical coupling.