Hardware design of hierarchal active-sensing networks for structural health monitoring

This paper presents the use of relay-based hardware in conjunction with piezoelectric active-sensing techniques for structural health monitoring in large-scale Structures. In many areas of active sensing technology, hundreds, even thousands, of sensors/actuators are needed to truly make health monitoring feasible in a real-world environment. Because interrogating such a large number of sensors is both time and cost prohibitive, it becomes necessary to develop a hardware system that can quickly and efficiently interrogate large numbers of the active sensors. In this work, we have developed a relay-based hardware that can serve as both a multiplexer and general-purpose signal router with special consideration given to piezoelectric active-sensing health monitoring approaches. We have also implemented this device as an expandable design that allows for easy scalability depending upon the size of the structure. Therefore, by using this hardware in Conjunction with a centralized monitoring station, any number of sensors can be monitored effectively. Preliminary testing of this hardware on a test structure has experimentally proven the feasibility and advantages. This paper summarizes the hardware design, scalability, and useful advantages given today's structural health monitoring techniques.