Optimal design of a 6-dof parallel measurement mechanism integrated in a 3-dof parallel machine-tool

This paper presents the design and the optimization of a parallel machine-tool composed of (i) an 3-dof actuated parallel mechanism (a linear Delta) and (ii) a 6-dof measuring parallel mechanism (a Gough platform).The measuring mechanism is used to control the actuated mechanism. The interest to use a measuring device independent of the actuation device is shown and the modeling of both devices used for the optimization is explained. Then, the optimization of both mechanisms is presented. The optimization of the actuated mechanism is performed to have an homogeneous behavior in velocity while the goal of the measuring device optimization is to obtain the best resolution for the measuring system evaluated at the tool level.