Design and Experiment of Vertical Motion Dual-stage with Piezo-actuated Nanopositioning Stage

Nanopositioning stage based on piezoelectric (PZT) actuators and flexure mechanisms has been widely used in dual-stage. Its favorable positioning accuracy and dynamic response can guarantee the high performance of the dual-stage. Here the vertical axis motion dual-stage is designed with piezoelectric actuator for the fine-stage and ball-screw drive integrated with wedge sliding mechanisms for the coarse-stage. The aim of the dual-stage is to meet the stringent requirement of scanning over a relative large range with high accuracy. The design results of the piezo-actuated nanopositioning stage show good static and dynamic performance, validated by the simulation of finite element analysis (FEA). Hysteresis nonlinearity due to the use of piezoelectric stacks for actuation is studied and compensated by a proportional-integral (PI) feedback controller. To qualify the design of the motion ranges and resolutions, an experiment platform is established. The experimental results show that the proposed dual-stage has a full range of 12 mm with the resolution of 40 nm. Guideline is provided for the design methodology of the vertical motion dual-range stages.