1. Structural health monitoring (SHM) involves observing a structure over time using sensor data to detect damage and assess structural condition and performance. 2. Vibration-based SHM techniques analyze changes in dynamic characteristics, like natural frequencies and mode shapes, detected from sensor data to identify damage existence, location and severity. 3. Model updating is a key SHM technique where an initial finite element model is updated by identifying parametric changes that minimize differences between sensor measurements and model predictions, potentially locating damage.