Microfabricated expandable sensor networks for intelligent sensing materials

Structural health monitoring (SHM) is a technology striving to enable automated evaluation of the health condition of structures. The SHM has recently attracted significant attention in the aerospace and civil infrastructure industries because of its potential to improve operational efficiency, reduce maintenance costs, and enhance the structural reliability in a real-time operation basis. The SHM is developing to include multiple types of sensors and even onboard processing for diagnostics and decision making. Advanced multidisciplinary engineering and manufacturing technologies are being developed enabling integration of sensors, network hardware, and semiconductors into structures with minimal parasitic effects. This is precisely the foundation for developing intelligent structures. This paper highlights recent developments in microfabricated expandable sensor networks for the SHM and intelligent structures at Stanford University. Fabrication and testing of microfabricated ultrasonic and temperature sensing systems in expandable networks are discussed. These advances applied to the SHM and intelligent structures support a paradigm change in design, manufacturing, and maintenance of structures. Successful implementation of the SHM will require a close collaborative effort among academia, government, and industry.