Design and analysis of a new compliant XY micropositioning stage based on Roberts mechanism

The demand for a compliant micropositioning stage with a large workspace and high precision is increasing. This paper presents a new design of XY micropositioning stage based on Roberts mechanism, which is a traditional linear guiding mechanism. By extending the traditional rigid-body Roberts mechanism, two kinds of new compliant guiding mechanisms are designed and a novel parallel-kinematic XY compliant guiding stage is synthesized. Pseudo-rigid-body model (PRBM) is developed to build the quantitative models of the compliant Roberts mechanisms. In addition, finite-element analysis (FEA) is carried out to validate its performance. A prototype is fabricated and tested through experimental studies. Results show that the XY stage delivers a work range larger than 12 mm in each axis. Moreover, the parasitic motion of the stage in the non-working direction is less than 1.7% of the motion stroke. It indicates that the designed stage meets the requirements of a large stroke and high precision linear guiding mechanism, which demonstrates the feasibility of the proposed design ideas using the Roberts mechanism.