Sensor Validation in Damage Locating Vector Method for Structural Health Monitoring

The reliability of a structural health-monitoring system is very dependent on the quality of signals that are acquired and fed into the damage detection algorithm. Developed herein is an algorithm for sensor validation in the context of the damage locating vector (DLV) method for detecting damage in structures. Given the signals from ns sensors, ns combinatorial sets of signals from (ns - 1) sensors are formed. For each set, the change in the flexibility matrix relative to that of the reference or undamaged structure is computed and singular value decomposition is performed to estimate the number of nonzero singular values (NZV). The set that produces the smallest NZV is associated with healthy sensors whereas sensors that do not belong to that combination are suspected to be faulty. The performance of the proposed algorithm is illustrated using both simulated and experimental data obtained from a 3D modular truss structure monitored by sensors, some of which are faulty.