Optimal Reference Allocation of Dual-Stage Measuring Machines

The dynamics of measuring machines are typically limited and do not suffice to fully exploit state-of-the-art metrology concepts. Therefore, dual-stage approaches become increasingly popular in this field. This paper uses a modeling approach including the lumped dynamic deviations and couplings between the actuators based on which optimal design paradigms are derived. Furthermore, the model is used to exploit the degree-of-freedom in the reference allocation considering the dynamic characteristics and limitations of each stage in a model predictive control fashion. A simulation study shows the benefits of the dual-stage approach as well as the proposed two-degree-of-freedom optimal reference allocation control structure.