The growing versatility and accessibility of Additive Manufacturing (AM) has led to increasing usage in criminal activities. In this presentation we provide an overview of recent research to forensically link AM parts to the three-dimensional (3D) printers or printer models that fabricated them. Here our focus is on the objective comparison of printer toolmarks or signatures in the surface texture of the manufactured parts.
AM parts are increasingly used in criminal activities. Of particular concern is the use of AM to fabricate illegal weapons at home. Examples are parts that illegally modify pistols for automatic fire or firearm components that circumvent serial number and background check requirements (i.e., “Ghost Guns”). Criminal uses have increased interest in forensic techniques that can link an AM part to a particular 3D printer or printer model.
One approach to this source attribution challenge is to identify and compare features in the geometry of fabricated parts, similar to the comparison of marks left by a firearm on a bullet or cartridge case. These features can be divided into class characteristics that are specific to a particular printer model and individual characteristics that are specific to a particular printer.
The National Institute of Standards and Technology (NIST) is conducting research to identify possible class and individual characteristics that are generated by consumer-level 3D printers. Examples are marks on the part left by the build plate or printer nozzle, or irregularities in deposition patterns. Optical profilers are used to acquire high-resolution 3D topography maps of part surfaces. Maps of part surfaces made by the same printer and by different printers are compared to identify possible class or individual characteristics and to evaluate their reproducibility. Results are used to define objective metrics that may enable linking an AM part to a particular printer or printer model.
Learning Objectives:
- Upon completion, participants will understand the importance of the research being performed in identifying class and individual characteristics of 3D printed parts.
- Upon completion, participants will be able to describe technology being researched for use in linking 3D printed firearm parts to the 3D printers they were printed from.
