Papers Published

  1. Gavin, Henri P., Lyapunov-based control of a base-excited structure, Proceedings of SPIE - The International Society for Optical Engineering, vol. 3325 (1998), pp. 12 - 22 [12.310606] .
    (last updated on 2007/04/09)

    Abstract:
    This study illustrates the behavior of a closed-loop vibration control system making use of electrorheological (ER) devices. Material properties of ER suspensions (primarily the yield stress, and visco-elastic properties) increase by several orders of magnitude when subjected to strong electrical fields (kV/mm). Because the electric field controls the yielding behavior of ER materials, ER devices are inherently non-linear. A Lyapunov-based controller is designed to to attenuate seismically-induced structural motions. Using this controller, the control decisions are independent of the structural model, and are therefore robust to modeling errors. Structures operated according to the control rule maintain an anti-resonant condition. This is demonstrated in the time-domain and the frequency domain. A numerical study, incorporating an evolutionary model for the ER device illustrates the robustness of this control method to model uncertainties.

    Keywords:
    Vibration control;Yield stress;Viscoelasticity;Electric field effects;Rheology;Resonance;Robustness (control systems);Friction;Earthquake effects;Model structures;Lyapunov methods;Decision theory;