Sensor Placement for Aerospace Vehicle Health Monitoring Systems

Structural Health Monitoring (SHM) systems that report in real-time a flight vehicle's condition are central to meeting the demanding goals of increasing flight vehicle safety and reliability while reducing costs. To detect damage with maximum probability, sensors must be placed optimally. This study develops a methodology for sensor placement optimization (SPO) for SHM systems under uncertainty. To achieve this, the structural component under consideration is analyzed via a finite element method (FEM) and model input uncertainties are included via random processes and fields. Probabilistic FEM analyses are performed to determine the model output variability and using their results, damage detection procedures such as feature extraction and state classification are applied to assess the current structural state of the component. Repeating these two steps using both healthy and damaged structural models allows for reliability estimates of a given sensor layout. Finally, SPO is achieved to maximize the reliability of damage detection. The sensor layout design of a thermal protection system component is presented to illustrate the proposed methodology.