Role of Control-Structure Interaction in Protective System Design

Abstract

Most of the current research in the field of structural control for mitigation of responses due to extreme environmental loads does not directly account for the effects of control-structure interaction and actuator/sensor dynamics in analysis and design. The importance of including control-structure interaction when modeling a control system is discussed herein, and a general framework within which one can study its effect on protective systems is presented. A specific model for hydraulic actuators typical of those used in many protective systems is developed, and a natural velocity feedback link is shown to exist which tightly couples the dynamics of the hydraulic actuator to the dynamics of the structure to which it is attached. Experimental verification of this model is given. Numerical examples are provided that use seismically excited structures configured with active bracing, active tendon, and active mass driver systems. These examples show that accounting for control-structure interaction and actuator dynamics can significantly improve the performance and robustness of a protective system.