A method and apparatus to safely repress disturbances from being applied
to a system from the surroundings in which the system is used. The method
of adaptively repressing disturbances includes estimating frequency
components of a disturbance applied to a system in a user environment;
and optimizing parameter values determining characteristics of a
disturbance compensating servo control loop including a disturbance
observer, based on the estimated frequency components of the disturbance.