Control system, lithographic apparatus, device manufacturing method and device manufactured thereby

摘要

A control system for positioning means 10 comprising a PID type controller 4, or other connected in a feedback loop. The controller calculates a current for supply to the positioning means 10 according to the error between the desired value of current Is and the measured value of current Im. This current is converted to a voltage by amplifier 6 and further modified by a feedforward voltage Uff calculated using mechanical and electrical characteristics of the positioning means and desired position and/or desired derivatives of position. <IMAGE>