A pseudo-rigid-body approach for determination of parasitic displacements of lumped compliant parallel-guiding mechanisms

Abstract

Parasitic displacements of a guiding plate of a lumped compliant parallel-guiding mechanism are analyzed using the pseudo-rigid-body (PRB) approach. Small deformations of flexure hinges are assumed. Each flexure hinge of the compliant mechanism is modelled by the PRB model with 3-DOF (degrees of freedom). This model allows that axial deformation of the flexure hinge to be considered. The corresponding expressions in symbolic form for both translational and rotational parasitic displacements of the compliant mechanism are derived. The obtained expressions enable the analysis of the influence of various structural parameters as well as various types of flexure hinges on the parasitic displacements of the considered type of compliant parallel-guiding mechanisms.