Time-delayed decentralized H₂/LQG controller for cable-stayed bridge under seismic loading

Abstract

SUMMARY Consistency of real‐time data transmission is an important factor in active and semi‐active control of structures. Recent advances in wireless sensors and their reliable data communication have attracted many attentions in structural control engineering. Wireless sensors have been also preferred to wire‐base types because of problems associated with installing extensive length of coaxial wires. In addition, embedded computing technologies in wireless sensors as local controller reduce size of transferring data and provide stable transmission. However, there are some issues in implementation of wireless connection like communication range and latency. This study presents the feasibility of developing a decentralized controller by using H2/LQG as robust‐optimum algorithm in cable‐stayed bridge. Because of large scale of structure, the order of model is reduced by using two different reduction methods in finite time and frequency. The controller is developed in centralized and decentralized solutions. The decentralized controller through developing a gradient‐based method is designed to efficiently solve system of closed‐loop H2 optimization problem. The structural responses in centralized and decentralized solutions are compared with each other under three different earthquake records considering time delay in data transmission. Results indicate that for large‐scale bridges with time‐delayed data communication issue, H2/LQG controller in decentralized solution gives maximum reduction of response indices in comparison with other strategies. Copyright © 2011 John Wiley & Sons, Ltd.

Recent advances in control algorithms for smart structures and machines

“…Fallah and Taghikhany () use the time‐delay H 2 /LQG control strategy to study decentralized control performance of a cable‐stayed bridge subjected to seismic loading. They reduced the large‐scale structure to a simpler model using information from the dominant frequencies of the structure.…”

Experimental investigations on seismic control of cable-stayed bridges using shape memory alloy self-centering dampers

“…De et al studied the efficient optimal design under uncertainty of passive control devices for a cable‐stayed bridge. To overcome the shortness of the passive dampers, active control devices, including the active tendon control methods and time‐delayed decentralized H2/LQG controller, were investigated. Although the active methods have high control performance, the necessity of the power supply and signals feedback makes the system too complex.…”

Online self‐tuning mechanism for direct adaptive control of tall building

“…In recent years, complex and large‐scale civil infrastructures with innovative uncertainty in the model of their structures, such as tall building and long bridges, have been attractive cases to control engineers. () Therefore, to overcome the challenge of uncertainty, some of the researchers have concentrated on designing control algorithms that are robust, such as H 2 or H ∞ controllers,() while others have tried to design controllers that can be adaptively updated to achieve the desired performance. These algorithms have drawn much attention to mitigate the negative influence of uncertainty on the gain of the control system.…”