Application of ensemble training of a structural controller to the AMD benchmark problem

Abstract

A benchmark structural control problem has been proposed in an attempt to evaluate the effectiveness of various control algorithms. The problem encompasses the design of an Active Mass Damper (AMD) control system for a Multi-Degree-Of-Freedom (MDOF) building type structure subjected to earthquake-type excitation. In vibration control for civil structures, linear quadratic optimal control is among the most popular techniques. Normally, this approach ignores the external excitation in the time-domain design process. In addition, this technique requires a full-order dynamic observer which is often unattainable. This paper focuses on the development of a new optimal control algorithm which includes the earthquake-type exctitation explicitly in the design of control systems and the use of prescribed-order, output feedback controllers. In addition, this approach allows the inclusion of open-loop (feedforward) as well as closed-loop (feedback) control terms in the controller design. The authors have previously designed an algorithm for full state feedback controllers trained on an ensemble of earthquakes. A cost functional is minimized on an ensemble of ‘known’ earthquakes, using analytic gradient information, in order to determine constant control gains. The gradients are obtained in explicit form. The control system is then validated by testing on ‘unknown’ earthquakes. The algorithm is now modified to develop a prescribed-order, output feedback controller for a specific MDOF system model. © 1998 John Wiley and Sons, Ltd.