Dissipated energy as the means for health monitoring of smart structures

摘要

NRL's Mechanics of Materials Branch has developed the Embedded Sensors for Smart Structures Simulator (ES) design tool which relates the output of a finite number of sensors to strain induced structural damage. This tool is based on the use of the dissipative part of the bulk nonlinear material behavior. The methodology used to identify this behavior has evolved at NRL over the past 20 years. This paper describes the role of strain measurements and their relation to sensor type and location, the conceptual framework of dissipated energy density as the metric employed for assessing material/structure performance, the facilities provided by the simulator and their use, as well as implementation details. Through this we hope not only to make designing and verifying embedded sensor layouts on composite material structures a tractable task, but also to promote the use of dissipated energy density as a foundation upon which to build an effective means of measuring material and structural health. 13