Disturbance suppression control combined disturbance ovserber with acceleration feedback in 2-dimensional shaking table system

This paper presents a controller design approach to suppress the disturbance in 2-dimensional shaking table systems. In the system, the overturning moment of specimen generated by the centroid movement as the disturbance generally deteriorates the motion performance of the table, resulting in the lower reproducibility for the desired earthquake acceleration. In this paper, therefore, a control approach based on the disturbance observer and the acceleration feedback to compensate for the overturning moment, which is one of deterioration factors for the reproducibility of acceleration waveforms. In the controller design, the acceleration feedback using an acceleration sensor is applied to suppress the resonant vibration, while the disturbance observer is designed to improve the disturbance suppression characteristic. The bandwidth of observer can be expanded by including the acceleration feedback loop. The proposed approach has been verified by experiments using a laboratory 2-dimensional shaking table system.