Robust Performance of Fuzzy Supervisory Control for Seismically Excited Cable-Stayed Bridge

Abstract

This paper investigates the robust performance of fuzzy supervisory control (FSC) technique for seismically excited cable-stayed bridge. The FSC technique utilizes fuzzy logic-based decision-making process to incorporate a set of pre-designed static control gains into a time-varying optimal control gain. To demonstrate the excellent robustness of the FSC technique on response control of earthquake-excited cable-stayed bridge, a conventional linear quadratic Gaussian (LQG) controller with single static gain and two fuzzy supervisory controllers are designed for the benchmark cable-stayed bridge, and their robust performances are examined under uncertainty in bridge model and against failures in actuators and sensors. Under the presence of uncertainty in the bridge model, the FSC system successfully reduces the seismic responses of the bridge without significant increase in the total amount of power and stroke required by the control system, while the LQG system exhibits a substantial increase in the seismic responses. Under conditions of sensor or actuator failures, the FSC system guarantees a more enhanced robust performance than the LQG system as well.