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International Journal of AI for
            Materials and Design                                                   AI applications in composite materials



            region, as shown in Figure 11B. However, challenges remain   on the  use of a VAE combined with Bayesian neural
            in detecting more subtle defects, such as loose tows and   networks (BNN) to quantify damage in composite plates.
            twists, where boundary detection becomes more difficult   This semi-supervised learning model helps with structural
            due to minimal height variations or uneven distribution   health monitoring by effectively handling the uncertainty
            of  defects.  One  of  the  reasons  for  this  limitation is  that   and measurement errors prevalent in damage detection.
            CNNs focus on learning local regions, making it difficult   The VAE-BNN model achieved high accuracy for several
            to capture global relationships. To address this limitation,   damage types, such as cracks and delamination, offering
            many studies have explored the use of other DL models.  improved robustness against noise compared to traditional
                                                               methods.
              For instance, Liu et al.  integrated a transformer-based
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            neural network with a CNN for automatic delamination   These  studies  exemplify  the  growing  impact  of
            detection in composite curved structures. This     automation models in improving quality control in
            transformer-based model can learn correlations among   composite material manufacturing. The presence of
            elements within the entire image through a self-attention   defects, such as voids or wrinkles, can significantly
            mechanism,  enabling  the  detection  of  defects  with  high   compromise the mechanical properties of composite parts.
            accuracy by considering patterns and morphological   By  automating defect detection  and enhancing defect
            information. Moreover, by utilizing enhanced terahertz   characterization, ML/DL technologies  are transforming
            time-domain spectroscopy signals for non-destructive   the production of composite materials, ensuring better
            testing  and imaging of  hidden  delamination  defects,   quality, reducing production times, and achieving cost
            the transformer-based approach demonstrated superior   savings in the long run. Moreover, the integration of
            accuracy  and  generalization  performance  compared  to   ML/DL allows for continuous monitoring and real-time
            traditional models, highlighting  its potential  for  real-  adjustments to further enhance the precision and efficiency
            time defect detection in complex composite structures.   of the production process.
            This method could be particularly beneficial in industries   4.2. Machine learning/deep learning-driven process
            such as aerospace, where structural integrity is critical. In   automation
            addition, the potential for ML/DL-driven automation in
            the quality control of the RTM process was demonstrated   The production of composite materials has traditionally
            by Wang  et al.  The PixelRNN model, an image-based   relied on the expertise of skilled professionals. While the
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            neural network architecture, was used to predict mold   work of these skilled experts remains an effective method
            filling patterns with high accuracy given the resin   for producing composite materials, the manufacturing
            injection location, as shown in Figure 11C. This model was   process is highly dependent  on external environments
            particularly effective in handling nonlinear filling patterns   and conditions and susceptible to human error, requiring
            and significantly reduced computational costs compared   advanced technical skills and labor-intensive efforts. In
            to traditional physics-based simulations. This highlights   addition, some processes may generate harmful chemicals
            the increasing role of ML/DL in process monitoring and   that might have negative impacts on the health of workers.
            automatic  detection  of  dry  spots  in  resin  impregnation   Due to these limitations, there has been an
            processes.                                         increasing interest in automation in composite material
              In addition, as described in Sections 3.2 and 3.3,   manufacturing. However, simple mechanical automation
            generative models, such as GANs,  VAEs,  and diffusion   is insufficient considering the complex shapes and variable
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            models,  were also used to detect and classify defects   manufacturing conditions associated with composite
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            in composite materials. In contrast to the methods of   materials. In other words, advanced AI-based automation
            defect  detection,  which  require  data  from  both  normal   technology with the flexibility to adapt to diverse shapes
            and defective samples, Szarski and Chauhan  developed   and complex conditions is essential for composite material
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            a model based on NFs to obtain the image likelihood of   manufacturing.
            a new sample using the knowledge learned from input   These  innovations  are  particularly  important  in
            images  of  only  normal  samples.  Considering  the  rarity   manufacturing processes, such as AFP, RTM, and composite
            and variety of defects, collecting training data is expensive   curing, where high precision and efficiency are critical. 127-129
            and time-consuming, and supervised learning proves to be   A hybrid framework combining spatial-temporal analysis,
            difficult. Instead of detecting the presence of defects, the   thermography, and ML algorithms was recently developed
            model determines whether the sample is different from a   for process monitoring and defect detection in AFP.  In
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            set of normal samples, without requiring any data from   this framework, an extensive thermal image database was
            defective samples. Furthermore, Zhang et al.   focused   used to train the model, achieving an impressive accuracy
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            Volume 2 Issue 3 (2025)                         21                        doi: 10.36922/IJAMD025210016
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