Disclosed is a disk drive using an accelerometer to sense linear vibration
and cancel its effects with an adaptive algorithm during track following. The accelerometer
is oriented to detect acceleration associated with torque that tends to cause the
actuator to move off-track notwithstanding the efforts of the servo control system.
The accelerometer's filtered output is used to modify the control effort. The disk
drive uses the position error signal to adaptively filter the accelerometer's output
in an effort to mathematically converge on a set of optimal filter coefficients
and thereby reduce the effect of vibration that may otherwise impose a torque on
the actuator.
