Performance-robustness trade-off in the control of a CD player using mixed objectives design

The purpose of the paper is to investigate the possibilities offered by multi-objective control in performing a systematic trade-off between performance and robustness issues in the control design of a CD player. In this control design problem the main goal is to keep the time domain amplitude of a tracking error signal bounded in the presence of disturbances and norm bounded uncertainties. Since these two requirements are conflicting, it is interesting to investigate what are the achievable trade-offs between them. Using a mixed objective approach, we construct Pareto optimal curves for this control problem, in correspondence to different choices of norms to represent the specifications. In this way we gain a considerable insight on what is achievable in this design. The resulting controllers are digitally implemented on the real system and validated on the basis of experimental results