Our deteriorating civil infrastructure faces the critical challenge of long-term structural health monitoring for damage detection and localization. In contrast to existing research that often separates the designs of wireless sensor networks and structural engineering algorithms, this paper proposes a cyber-physical codesign approach to structural health monitoring based on wireless sensor networks. Our approach closely integrates 1) flexibility-based damage localization methods that allow a tradeoff between the number of sensors and the resolution of damage localization, and 2) an energy-efficient, multilevel computing architecture specifically designed to leverage the multiresolution feature of the flexibility-based approach. The proposed approach has been implemented on the Intel Imote2 platform. Experiments on a simulated truss structure and a real full-scale truss structure demonstrate the system's efficacy in damage localization and energy efficiency.

We propose a new adaptive modeling algorithm, nonlinear multidegree-of-freedom (NLMDF). The underlying idea is to assimilate the adaptive modeling process of iteration for the optimal solution to a particle's movement on the mean-square error (MSE) surface geometry, which is imagined to be located in the gravitational field. The new algorithm is derived by incorporating a viscous damping force in the particle movement differential equation. A new variable step size least mean square (LMS) algorithm-new variable step LMS (NVLMS)-is derived from the NLMDF algorithm by choosing specific value for the damping parameter in the NLMDF recursion. The simulation results show a faster rate of convergence for the new algorithms as compared with the damping force LMS (DFLMS) algorithm and the LMS algorithm with a white or colored noise input signal.