  Additive manufacturing has the potential to become a standard method for
manufacturing products, and product information is indispensable for the item
distribution system. While most products are given barcodes to the exterior
surfaces, research on embedding barcodes inside products is underway. This is
because additive manufacturing makes it possible to carry out manufacturing and
information adding at the same time, and embedding information inside does not
impair the exterior appearance of the product. However, products that have not
been embedded information can not be identified, and embedded information can
not be rewritten later. In this study, we have developed a product
identification system that does not require embedding barcodes inside. This
system uses a transmission image of the product which contains information of
each product such as different inner support structures and manufacturing
errors. We have shown through experiments that if datasets of transmission
images are available, objects can be identified with an accuracy of over 90%.
This result suggests that our approach can be useful for identifying objects
without embedded information.
