Automatic tuning of finite spectrum assignment controllers for delay systems

The finite spectrum assignment (FSA) for delay systems has been proposed in the literature for many years, but its application has not been investigated. In this paper, several practical issues with the FSA are considered. First, a modified FSA (MFSA) is presented to achieve asymptotic tracking and regulation. Secondly, an automatic tuning technique is developed for the MFSA controllers using a relay feedback plus a step test. Thirdly, it is shown that the auto-tuned MFSA systems are practically stable provided that the process is stable, and therefore they are robust with respect to small perturbations in process dynamics. Both simulations and experimental results are included for illustration.