In wireless structural health monitoring systems, the inherent processing power of wireless sensor nodes enables the execution of structural health monitoring tasks in a decentralized manner. Decentralization may result in non-synchronized sets of structural response data, for example due to non-simultaneous triggering of the sensor nodes. Lack of synchronization is detrimental to the output of operational modal analysis (ΟΜΑ), which is frequently applied in SHM, leading to erroneous structural mode shapes. From a computer science perspective, synchronization approaches in wireless SHM systems center around clock synchronization schemes. In this paper, an embedded algorithm is presented that enables wireless sensor nodes to detect and to accommodate synchronization problems. The proposed algorithm draws from the theory of OMA and the expected relationship between the phase angles of frequency components corresponding to mode shapes obtained from different sets of structural response data. The embedded algorithm is implemented into a wireless SHM system and validated through laboratory tests on a shear frame structure.
