A kinematically decoupled 6-DOF nanopositioning stage with minimised crosstalk based on flexure hinges

Abstract Six-degree-of-freedom (6-DOF) nanopositioning stages are indispensable in precision engineering. However, these stages currently exhibit significant crosstalk, which degrades their accuracy. This study proposes a kinematically decoupled 6-DOF nanopositioning stage with minimized crosstalk based on flexure hinges, and its conceptual design, modelling, and experimental investigation are described. First, the working principle of the stage is introduced, followed by its design mechanism with flexure hinges. Second, its stiffness model is established using Castigliano’s second theorem, which is then utilized for the optimization design. Finally, an experimental study conducted based on the fabricated prototype is described. The results reveal that the positioning stage features a resolution better than 20 nm, 0.07μrad, and set-point tracking accuracy better than 0.029μm and 0.192μrad for translation and rotation, respectively. Most importantly, its static single-axis crosstalk over the full range is less than 0.81%, and its dynamic crosstalk is reduced to less than 0.103μm and 0.778μrad, using a simple proportional–integral–derivative (PID) controller and quintic polynomial trajectory planning, respectively.