Optimal Design, Modeling and Analysis of a 2-DOF Nanopositioning Stage with Dual-Mode: Towards High-Rate AFM Scanning

A compliant 2-DOF nanopositioning stage with a novel concept of dual-mode driven is proposed in this paper aiming to improve the scanning performance of the Atomic Force Microscope (AFM). The stage is featured with nanoscale positioning precision, high bandwidth, long scanning range and fully decoupled structure, which can be selected to work in dual working modes. Based upon the matrix method, the discussions in terms of output compliance, input stiffness and dynamics modeling via Lagrange equation have been performed in detail. Moreover, a series of optimal designs have been implemented using Particle Swarm Optimization (PSO) algorithm. The results of the finite-element analysis (FEA) indicate that the first natural frequency is approximated 583 Hz, the amplification ratio in two axes is about 4, thus the maximum scanning range can reach up to around 341 mu m x 341 mu m without material failure, while the cross-coupling between the two axes is kept within 2%. All the results indicate that the presented mechanism possesses a good performance for high-rate AFM scanning.