Wireless Sensing and Decentralized Control for Civil Structures: Theory and Implementation

Structural health monitoring and control have attracted much research interest over the last few decades. With recent advances in wireless communication technology, wireless networks can potentially offer a low-cost alternative to traditional cable-based sensing and control systems. Another advantage of a wireless system is the ease of relocating sensors and controllers, thus providing a flexible and reconfigurable system architecture. In the first stage of this research, a prototype wireless structural sensing system is developed. This integrated hardware and software system is designed and implemented using low-cost off-the-shelf electronic components. Hardware drivers, data streaming protocols, and various computational algorithms (such as the Fast Fourier Transform and auto-regressive analysis) have been successfully embedded in the wireless sensor nodes. Operating deflection shape analysis of bridges spanning hundreds of feet has been successfully carried out using the high-quality sensor data collected by the wireless system.

The functionality of the wireless structural sensing system is extended to support feedback structural control. Hardware and software interfaces are designed so that the wireless sensing units are capable of processing real-time sensor data, making control decisions, and commanding structural actuators. The wireless structural feedback control system has been successfully validated using a half-scale three-story laboratory structure instrumented with magnetorheological dampers. Provided the range and bandwidth constraints of wireless communication technologies, centralized control architectures are difficult to implement in a wireless control system. As a result, also validated during the experimentation is the potential of applying decentralized control architectures, in which an actuator only requires data from neighboring sensors for control decisions. Numerical simulations have been conducted to further evaluate the feasibility of applying decentralized wireless control for large-scale building structures.