Sensor validation for structural systems with multiplicative sensor faults

Structures with a large number of sensors and actuators are becoming more common, with applications that vary from active control to damage location. This large amount of spatial information should be used to the advantage of the analyst, which requires, for correct functioning, the continuous in-operation monitoring of the sensors. Errors introduced by faulty sensors can cause a loss of performance and erroneous conclusions. Most of the currently available techniques seem to work well under the assumption of additive fault conditions, while seem to fail under the condition of multiplicative faults. In this work, we propose a new residual generation and evaluation technique for sensor validation that works for both additive and multiplicative faults. A correlation index is proposed which isolates the faulty sensors. The approach is experimentally validated on a subframe structure.