Patent ID: 6465981
Filing Date: 2002-10-15
Classification: G05B,G11B

Abstract:
A servo loop in a disc drive for positioning a head over a disc while maintaining servo loop stability, the servo loop comprising:an actuator-head assembly comprising the head, a large-scale actuator, and a micro-actuator, both the large-scale actuator and the micro-actuator configured to move the head over the disc, and the head configured to generate a position value based on its location over the disc; a micro-actuator controller configured to generate a micro-actuator control value to control the micro-actuator based on a position error value; a saturation adjustment component coupled to the micro actuator controller and configured to generate a saturation error value based on the micro-actuator control value; and an adaptive anti-windup circuit coupled to the saturation adjustment component and configured to transfer control to the large-scale actuator in response to the saturation error value generated by the saturation adjustment component.