From April 13 to 17, 2025, the Polytechnic University of Bari took part in the SPIE Thermosense – Defense and Commercial Sensing Conference held at the Gaylord Palms Resort & Convention Center in Orlando, Florida, presenting cutting-edge research in structural health monitoring (SHM) through thermal methods applied to 3D-printed composite materials.
The participation was part of the activities of CO-SMART, a national project supported by the Center for Sustainable Mobility (MOST) and funded by the Italian Ministry of University and Research through PNRR – NextGenerationEU resources.
The study was led by the Mechanics Group of the DMMM Department (Structural Diagnostics and Thermal Methods), with a team composed of Ester D’Accardi, Davide Palumbo, Rosa De Finis, and Umberto Galietti, in collaboration with the University of Salento and the Polytechnic University of Turin.
Thermography and 3D printing: toward accessible, real-time monitoring
The research introduced innovative strategies for damage monitoring in additively manufactured composite materials, leveraging Thermoelastic Stress Analysis (TSA) — a non-contact, rapid, and full-field technique capable of detecting thermal variations caused by cyclic loading.
The main goal was to assess the effectiveness of low-cost infrared sensors — such as the FLIR BOSON and FLIR Lepton — as alternatives to the expensive cooled cameras traditionally used (e.g., FLIR X6540sc).
Experimental tests were performed on 3D-printed composite specimens with different laminate configurations (Quasi-Isotropic, Cross-Ply, and Angle-Ply), purposely designed with central holes to trigger crack initiation.
Damage monitoring was conducted during accelerated fatigue tests, with real-time acquisition and analysis of thermal sequences processed through signal analysis algorithms and Matlab post-processing techniques.
From lab to application: SHM for the new manufacturing era
Results show that using compact and affordable microbolometric sensors enables the quantitative assessment of damage evolution even in dynamic and in-service conditions.
In particular, the BOSON sensor — low-cost and small-sized — proved capable of detecting quantitative thermal signals associated with the initiation and propagation of structural damage, in good agreement with traditional cooled systems.
The Lepton 3.5 sensor, although limited in resolution and acquisition rate, also provided promising qualitative insights, especially in the final stages of the tests, paving the way for low-cost rapid screening applications.
A step forward for the sustainable mobility industry
This research aligns with the strategic goals of Spoke 11 of the CO-SMART project, focused on innovative and lightweight materials, and addresses the growing demand for intelligent and scalable monitoring technologies for complex structural components used in automotive, aerospace, and railway sectors.
Through this initiative, the Polytechnic University of Bari reaffirms its role as a leading institution in thermal diagnostics and structural health monitoring, contributing to the transition toward a more sustainable, efficient, and safe mobility future.
