A voltage-mode VCM controller is provided comprising an Infinite Impulse
Response (IIR) filter that modifies a servo control voltage signal to a
voltage driver in response to an adaptive compensator that configures the
IIR filter in relation to an observed VCM velocity and an actual VCM
velocity. An associated method is provided comprising modeling a velocity
response of a VCM to a voltage input; inputting the observed velocity and
an actual VCM velocity to an adaptive compensator that computes a gain
and a VCM response pole frequency in relation to the VCM resistance and
inductance; configuring an IIR filter in relation to the computed gain
and pole frequency values; and using the IIR filter to modify a voltage
command from a servo controller to a power driver.