Adaptive Sliding Mode Control for Structural Vibration Using Magnetorheological Damper

This study presents the design of a new adaptive sliding mode controller to mitigate building vibrations induced by earthquakes, utilizing a semi-active magnetorheological damper (MRD) positioned on the top floor. This damper operates as a passive damper under low-intensity vibrations and transitions to an active damper during high-intensity vibrations, facilitating optimized performance according to vibration severity. The efficiency of the proposed controller was assessed by comparing it with two other robust controllers established in previous studies. This comparison was performed on a prototype three-story structure, subjected to a severe earthquake called El Centro 1940 with an acceleration of 3.9 m/s². The simulation results demonstrated that the proposed controller effectively reduced vibrations significantly. The proposed controller demonstrated enhancement in control effort 660N compared to 751N for first methodology and 722N for second methodology from the literature. The proposed method offers the advantage of reduced design requirements relative to the first and second methods from literatures. Moreover, the proposed method eliminates the necessity for filter adjustments, hence simplifying its implementation. All controllers utilized for comparison are robust and do not require prior knowledge of disturbance bounds. Moreover, the damper was positioned on the top floor in all the procedures analyzed. The results indicate that the proposed controller significantly reduces control effort relative to alternative controllers in addition The proposed method reduces the displacement of the upper floor by 89% compared to other methods, rendering it an effective choice for vibration control and enhancing building reactions to earthquakes.