Title
Spatio-Temporal 3-D Residual Networks for Simultaneous Detection and Depth Estimation of CFRP Subsurface Defects in Lock-In Thermography
Abstract
Nondestructive thermography is a high-speed, low-cost, and safe solution for subsurface defects detection of carbon fiber reinforced polymer (CFRP) materials, providing essential quality control in aerospace, automobile, and sports industries. In this article, we build a reflective lock-in thermography system and construct a dataset that contains real-captured thermal image sequences of CFRP samples with various simulated internal defects under different excitation frequencies. Then, we present a novel 3-D convolutional neural network (CNN) model incorporating a combination of spatial and temporal convolutional filters and batch-size independent group normalization (GN) as a unified framework to process thermal image sequences captured by lock-in thermography for simultaneous subsurface defect detection and depth estimation. Finally, we define a multitask loss function to perform end-to-end training of both defect detection and depth estimation tasks based on the real-captured infrared sequences. Comparative experiments are carried out on CFRP specimens with artificial defects of various sizes/shapes and at different depths. Qualitative and quantitative results illustrate that our 3-D CNN model is capable of predicting accurate locations and depths of subsurface defects and performs favorably against the hand-crafted and CNN-based methods in lock-in thermography for individual defect detection and depth estimation tasks. The captured dataset and the source codes will be made publicly available.
Year
DOI
Venue
2022
10.1109/TII.2021.3103019
IEEE Transactions on Industrial Informatics
Keywords
DocType
Volume
Carbon fiber reinforced polymer (CFRP),defect detection,depth estimation,lock-in thermography,nondestructive testing,spatio-temporal 3-D convolution
Journal
18
Issue
ISSN
Citations 
4
1551-3203
0
PageRank 
References 
Authors
0.34
0
6
Name
Order
Citations
PageRank
Yafei Dong100.34
Chenjie Xia200.34
Jiangxin Yang3407.68
Yaolong Cao4167.86
Yanpeng Cao5306.32
Xin Li632.48