Large dynamic range tracking of an XY compliant nanomanipulator with cross-axis coupling reduction

This paper presents a novel design on a large range compliant XY nanomanipulator with spatial constraints to reduce parasitic motions. Aiming at periodic trajectory tracking of the proposed XY parallel compliant nanomanipulating system, a disturbance observer based (DOB) repetitive control structure is developed such that the cross-axis coupling effects and the stiffness nonlinearity can be treated as disturbances with harmonic and non-harmonic components for rejection purposes. The mechanical design prototype is fabricated and the proposed control algorithm is experimentally validated, where enhanced tracking performance with cross-axis coupling reduction is demonstrated by achieving tracking errors less than 80 nm and a motion stroke over 1 mm.