Pull-in control during nanometric positioning by near field position sensing

Sylvain Blanvillain (1) , Alina Voda (1) , Gildas Besancon (2)

1 GIPSA-SLR - GIPSA - Systèmes linéaires et robustesse
2 GIPSA-SYSCO - GIPSA - Systèmes non linéaires et complexité

This paper deals with the pull-in control and the nanopositioning of an electrostatically actuated NEMS (Nano Electromechanical System) squeezed between two forces. It is shown that when a position sensor is driven close to a NEMS, pull-in occurs due to electrostatic forces, but also to near field forces acting at nanoscale, namely Casimir and Van der Waals forces. Pull-in conditions are investigated to find the minimum pull-in distance depending on the parameters of the system. This paper aims to demonstrate that the sensor can be driven below this minimum pull-in distance. To do so, a control strategy based on a nonlinear feedback design and on a robust pole placement/sensitivity function shaping is proposed. Furthermore, it is shown that the NEMS position can be controlled without contact while avoiding pull-in and decreasing its natural brownian motion.

Mots clés: Terms--NEMS; Pull-in; nano positioning; nonlinear feedback; robust control; stability

Domaines: Automatique

Sylvain Blanvillain, Alina Voda, Gildas Besancon. Pull-in control during nanometric positioning by near field position sensing. CDC 2008 - 47th IEEE Conference on Decision and Control, Dec 2008, Cancun, Mexico. pp.5194-5199. ⟨hal-00371264⟩