ZOLOTAS, A.C. and HALIKIAS, G.D., 1999. Optimal design of PID controllers using the QFT method. IN: IEE Proceedings - Control Theory and Applications, 146 (6), pp. 585 - 589
An optimisation algorithm is proposed for designing PID controllers,
which minimises the asymptotic open-loop gain of a system, subject to appropriate robuststability
and performance QFT constraints. The algorithm is simple and can be used to
automate the loop-shaping step of the QFT design procedure. The effectiveness of the
method is illustrated with an example.