MODEL IDENTIFICATION AND CONTROL OF A TUNED LIQUID DAMPER

Experimental studies have been conducted to investigate the feasibilit y of using active control of the tuned liquid damper for reducing the vibration of large civil structures. The results indicate that a simpl e mechanism can be designed to actively control the tuning of the syst em by adjusting the length of the liquid tank with rotatable baffles d riven by stepping motors. The tank can be permanently installed and no powerful actuators would be required to regulate its motion. As a res ult, the system can be built inexpensively and can be tested frequentl y to ensure its reliability. A control strategy based on detection of frequency content and two-state control is simple and can be easily im plemented in a microprocessor. Preliminary results of the damper model identification are provided, allowing computer simulations and the de sign of advanced control strategies for fine tuning of the liquid damp er in future studies. The performance of this novel damper is verified by computer simulations and experiments using a physical model. (C) 1 997 Elsevier Science Ltd.