Patent ID: 8179751

Claim:
A method for generating a control voltage for a position actuator of a disk drive system for displacing a lens of a pick-up unit to a given position, wherein the actuator is operated by an open loop control system, said method comprising: calibration of the control system for producing only a single control voltage (Va) from an input position signal (Xact_setp) to the control system; processing only said single control voltage (Va) in a feed forward system for generating only a single processed control signal (Va_p), wherein said processing of only said single control voltage (Va) is performed as a function of the present axial (Z) position of the actuator, the present temperature, the (Z) position of the actuator during calibration, and the temperature during calibration, feeding only said single processed control signal to said position actuator for displacing said lens to said given position wherein said calibration step calibrates at least one of parameters K, R and C, where K=property of ‘actuator’: Newton/Ampere R=resistance of ‘actuator’ coil C=Spring constant in Newton/meter.