Optimization of Embedded Sensor Placement for Structural Health Monitoring of Composite Airframes

This study develops an optimization method specifically for embedded sensors for structural health monitoring of a composite laminated aircraft structure. The chosen cost function is the component lifetime, balancing both the positive benefits of the condition-based monitoring enabled by the sensor information with the negative costs of the structural-performance degradation. The optical-fiber spacing is optimized, rather than the placement of individual sensors. Sensor interaction with damage and sensor-feature extraction are included into the optimization problem through experimentally derived probabilistic models. The resulting sensor-placement optimization has regions of decreasing laminate lifetime and regions of increasing laminate lifetime as a function of sensor spacing. A critical sensor spacing is also calculated, below which sensors are not recommended to be embedded.