A Compact Electromagnetic Dual Actuation Positioning System with a 10 mm Range and Nanometer Resolution

Abstract

In this manuscript, a compact electromagnetic dual actuation positioning system (CEDAPS) based on the Lorentz force principle that features a 10 mm range and nanometer-scale resolution with flexure guides is presented. Firstly, the stiffness of the flexure mechanism is modelled. Secondly, based on it, the primary coil is designed, and from its performance, a suitable secondary coil is made to compensate for the deficiency of the primary actuation subsystem. The characteristics of the forces generated by these coils are also evaluated by an electromagnetic FEA simulation. Thirdly, a control scheme is presented that combines the performances of these two actuators, and finally, a prototype is fabricated to evaluate the performance. The results show a 10 nm resolution for a 10 mm (±5 mm) stroke with low sub-micron sinusoidal tracking errors and nanometer accuracy for step tracking under the proposed control scheme. The thermal properties of the system are also presented.