A Proposal for Exteriori-Interiori Integrated Structural Health Monitoring Framework

The motivation of this study is to determine a technique to completely describe the damage state of large deformed structures commonly found during forensic investigations. The combination of Laser Detecting and Ranging (LiDAR) and Piezoelectric (PZT) sensing technologies for damage quantification is suggested to generate a full-field description of a permanently deformed plate. The test subject is a 16 inch by 16 inch aluminum plate subjected to different damage scenarios. LiDAR is a static scanning laser that provides a 3-dimensional picture of the object. Smart Layer is a commercial PZT actuator/sensor network system that generates stress waves for internal damage evaluation. Both techniques have been applied to the test plate after damages were introduced. In order to effectively analyze the results, the images for each test were superimposed. Four damage scenarios were imposed on the aluminum plate including saw cuts at different depths using an electric saw. The final damage is a severe bending of the plate. The bending of the specimen produced an image that located the most severe damage directly under the left hand portion and directly above the right hand portion of the bend. We propose a structural health monitoring framework, EII-SHM (exteriori - interiori integrated structural health monitoring) that can completely quantify damage on a severely deformed structure. The EII-SHM framework involves workflow in conducting a forensic investigation where exteriori scans using scanning LiDAR is first conducted followed by interiori scan using piezo sensor network. The lidar scan can help determine critical locations of the piezo sensors, hence, optimize sensor placement and number of sensors.