Model uncertainties and actuator delays are two factors that degrade the performance of active structural control systems. A new robust control system is proposed for control of an active tuned mass damper (AMD) in a high-rise building. The controller comprises a two-loop sliding model controller in conjunction with a dynamic state predictor. The sliding model controller is responsible for model uncertainties and the state predictor compensates for the time delays due to actuator dynamics and process delay. A reduced model that is validated against experimental data was constructed and equipped with an electro-mechanical AMD system mounted on the top storey. The proposed controller was implemented in the test structure and its performance under seismic disturbances was simulated using a seismic shake table. Moreover, robustness of the proposed controller was examined via variation of the test structure parameters. The shake table test results reveal the effectiveness of the proposed controller at tackling the simulated disturbances in the presence of model uncertainties and input delay.

SummaryThe active disturbance rejection control of a delayed 2-degree-of-freedom structure against earthquake motion force is investigated. A shaking table that resembles the acceleration profiles of most known earthquakes is used to generate the horizontal force. To compensate the motions caused by the earthquake simulator, an active tuned mass and damper system is attached to the structure. Due to the strong effects of the motion forces as a disturbance input, an active disturbance rejection controller including an extended state observer is designed and implemented. The controller designed is modified with including a state predictor to address the control input delays induced by the remote networked control or actuator delays. The stability of the whole system is verified via Lyapunov analysis and tested on the structure sample including shaking table. The results show the effectiveness of the proposed approach to regulate the structure motions in different earthquake scenarios.