The Quantitative Feedback Design of the Benchmark Problem

The quantitative feedback theory (QFT) is applied to the benchmark problem [1]. The key idea is to synthesize controllers that meet the time domain design specifications by satisfying an approximately "equivalent" set of frequency domain constraints on the magnitude and phase of a nominal loop transfer function at each frequency. In addition, the effects of the sensor noise are minimized by minimizing the cost of feedback or the bandwidth of the controller transfer function. It is shown that the devised control system meets all the frequency domain design specifications for all possible plants P in the plant set P.