Apparatus and method for adaptive suppression of vibrations in mechanical systems

DETAILED DESCRIPTION In a broad aspect, the invention involves a method and apparatus for stabilizing at least one element of a mechanical system against echo-like responses to mechanical disturbances.
One or more error signals are provided by sensing the motion of the system at one or more points.
At least one adaptive filter is operated in response to the error signal or signals, and in response to at least one non-advanced reference signal that is directly related to some motion of the system.
The adaptive filter produces a corrective signal for driving a mechanical actuator, thereby to apply to the element a stabilizing generalized force.
By non-advanced is meant that there is a zero or negative time-delay between the presence of a given signal at the reference-sensing location and the arrival of the same, or a similar, signal at the error-sensing location.
In particular embodiments of the invention, the reference-sensing location is the same as the error-sensing location.