Planar motor concept for positioning with nanometer position uncertainty

摘要

The realisation of a position uncertainty in the nanometer range together with travel ranges in the order of several 100 mm is a topic that research groups worldwide are working on. As a part of the SFB 622 the IMMS takes part in research work for the realisation of nanopositioning -and nanomeasuring machines (NPM/NMM) for large travel ranges [1]. The basic concept for such machines is to position a Zerodur? reflector and to measure the movement in all axes very precisely with laserinterferometers mounted to a stable metrology frame [2, 3]. Thereby one major challenge is to provide large travel ranges for the lateral positioning of the reflector together with reproducibilities and even uncertainties in the nanometer range. Long structural loops, mechanical resonances, friction and thermal effects as well as position dependent changes in the system transfer behaviour turn out to be critical factors that determine the performance limits of conventionally structured positioning systems.