Applications of mixed H2 and H-infinity input design in identification

The objective of this contribution is to quantify benefits of optimalinput design compared to the use of standard identification inputsignals, eg PRBS signals for some common, and important, applicationareas of system identification. Two benchmark problems taken from processcontrol and control of flexible mechanical structures are considered.We present results both when the design is based on knowledge of thetrue system (in general the optimal design depends on the systemitself) and for a practical two step procedure when an initial modelestimate is used in the design instead of the true system.The results show that there is a substantial reduction in experimenttime and input excitation level. A discussion on the sensitivity ofthe optimal input design to model estimates is provided.