• Author(s): Akshat Dave, Tianyi Zhang, Aaron Young, Ramesh Raskar, Wolfgang Heidrich, Ashok Veeraraghavan

“NeST: Neural Stress Tensor Tomography by leveraging 3D Photoelasticity” introduces a groundbreaking approach to stress tensor field reconstruction using deep learning and photoelasticity. This research addresses the challenge of accurately measuring and visualizing stress distributions in complex 3D objects, which is crucial for various engineering applications, such as product design and failure analysis.

The proposed method, named NeST (Neural Stress Tensor Tomography), combines the principles of photoelasticity with deep learning techniques to enable non-destructive stress tensor field reconstruction. Photoelasticity is an optical method that utilizes the birefringence property of transparent materials to visualize stress distributions. By leveraging this phenomenon, NeST can capture the stress-induced changes in the polarization state of light passing through a stressed object. At the core of NeST is a deep neural network architecture that learns to map the captured photoelastic images to the corresponding stress tensor fields. The network is trained on a large dataset of simulated photoelastic images and their associated stress tensor fields, generated using finite element analysis. This data-driven approach allows NeST to learn the complex relationships between the observed photoelastic patterns and the underlying stress distributions.

One of the key innovations of NeST is its ability to reconstruct stress tensor fields in 3D. Traditional photoelastic methods are limited to 2D stress analysis, but NeST extends this capability to three dimensions by employing a tomographic reconstruction algorithm. By capturing photoelastic images from multiple viewing angles and feeding them into the trained neural network, NeST can reconstruct the complete 3D stress tensor field of the object.

The paper provides extensive experimental results to demonstrate the effectiveness of NeST. The authors evaluate their approach on both simulated and real-world datasets, showcasing its ability to accurately reconstruct stress tensor fields in various 3D objects. The reconstructed stress fields exhibit high fidelity and closely match the ground truth obtained from finite element simulations.

Furthermore, the paper highlights the practical applications of NeST in fields such as mechanical engineering, aerospace, and biomedical engineering. The ability to non-destructively measure and visualize stress distributions in complex 3D objects opens up new possibilities for optimizing designs, predicting failures, and understanding the mechanical behavior of materials.

“NeST: Neural Stress Tensor Tomography by leveraging 3D Photoelasticity” presents a significant advancement in stress tensor field reconstruction. By combining deep learning with photoelasticity, NeST enables accurate and non-destructive measurement of stress distributions in 3D objects. This research has important implications for various engineering disciplines, providing a powerful tool for analyzing and optimizing the mechanical performance of structures and components.