Performance-recoverable intelligent digital redesign for fuzzy tracking controllers

Performance-recoverable intelligent digital redesign (IDR) in a fast sampling limit is proposed for fuzzy tracking controllers with time-varying references. IDR uses a delta operator and a piecewise linear—rather than constant—approximation of the reference improve the state-matching performance for both an extremely small and a large sampling period T∈R>0T∈R>0, respectively. It is proved that the analog control performance is recovered by the proposed intelligently digitally redesigned sampled-data controller in three perspectives—controller gain, stability, and closed-loop trajectory—when T goes to zero.