Vibration Control of Uncertain Based Steel Structures with Quantitative Feedback Theory and H Infinity Norm

Quantitative Feedback Theory, QFT, is frequency-domain-based robust control design methods that can conquest to structured uncertainty. In the last few years, its application to several control systems design such as flight control, hydraulic actuator control, etc., has been widely investigated but this theory has not been developed in the structural control field. The QFT method offers a direct design technique for satisfying a set of robust performance and stability objectives over a given range of plant parameter uncertainty based on Nichols Chart. In this paper firstly the QFT design methodology is presented through one illustrative example in order to make easy understanding of the basic principles and characteristics for single-input single-output system. Afterwards, feasibility and the efficiency of new structural control method are demonstrated by numerical simulation in multi degree of freedom structure and compared with the robust design approach. Simulation results show that the lower order of QFT controller is important feature of QFT controller in civil engineering.