Design and Optimization of a Long Travel, Two-Axis Flexural Nanopositioning Stage

Abstract Multi-axis nanopositioning stages based on compliant mechanisms are a common topic within modern precision engineering due to their high accuracy, repeatability, and low cost compared to industry positioning stage alternatives. This paper details the design, computational optimization, and result evaluation of a two-axis flexural nanopositioning stage based on a modified version of the classic double parallelogram flexure (DPF) bearing (e.g. an underconstraint-eliminating DPF (UEDPF)). The two-axis flexural nanopositioning stage was optimized using response surface model with seven inputs and two outputs. The seven input parameters were the most sensitive geometric parameters for the UEDPF identified in previous work, and the two outputs were the flexure’s peak stress at maximum deflection and the force reaction felt by the 25mm displacement boundary condition. This paper shows that through design optimization, the first resonant mode of a long travel, two-axis flexural nanopositioning stage that has previously been reported in literature can be improved by a factor of two while still maintaining the higher-order resonant modes to be at least an order-of-magnitude higher than the fundamental mode of the stage. This is critical because increasing the fundamental mode without sacrificing the higher order modes will allow for a higher bandwidth controller to be implemented on this nanopositioning stage. The end goal of the positioning stage detailed in this paper is to be implemented within a micro-SLS 3D printer.