Micro-motion selective-actuation X Y Z flexure parallel mechanism: design and modeling

This paper presents the design of a selective-actuation flexure parallel mechanism that can provide three de-coupled micro-motions along the X -, Y - and Z -axes. This mechanism can be used as an ultra-precision positioning system. The modeling of this flexure parallel mechanism is then established based on a pseudo-rigid-body model with consideration of deformation of the flexure member. The factor of deformation allows us to formulate the accurate kinematics analysis of the flexure mechanism. Via this modeling, dimension and free shape of the mechanism are determined based on the criteria of isotropic resolution transmission scale. An experiment was set up to verify the modeling and the design. The experiment shows the advantage of the proposed model versus the model currently used. The similarity of the resolutions obtained from the experiment and predicted by the optimal design shows the validity of the resolution evaluation and the optimal design.