How safe is your additive manufacturing process?

In the last 30 years, additive manufacturing (AM)/3D printing (3DP) went from scarcely known to highly hyped – a technology that was going to have people printing everything and anything they needed at home. In typical tech cycles, the hype settles down, the technology and materials advance, and manufacturers find their stride when it fits into operations.

Companies are applying AM/3DP for prototypes, tools, fixtures, and finished products, such as customization of medical implants. More information can be found in this month’s infographic, such as top processes, locations, materials, and other drivers in a market projected to reach $9.8 billion by 2025. Used consistently in the orthopedic market for nearly a decade, analysts estimate that 44% of all medical 3D printing revenues come from this sector, expecting continued growth to more than 60% of all associated revenues by 2020.

However, users need to ensure the process is safe and repeatable, protecting against malicious software attacks and unscrupulous operators. That’s the approach a group of researchers at the Georgia Institute of Technology and Rutgers University are developing with funding from the National Science Foundation (NSF).

The researchers have a developed a three-layer system that verifies additively manufactured components have not been compromised. The method uses acoustic and other physical techniques to confirm that the printer is running as expected, and implements non-destructive inspection techniques to verify the correct location of tiny gold nanorods buried in parts.

According to the researchers, who presented their findings last month at a security symposium, the system includes:

• Acoustic measurement of the 3D printer in operation – A microphone and filtering software compare the build to a reference recording of a correct print. Acoustic monitoring can detect changes in the printer’s sound that may indicate installation of malicious software.
• Physical tracking of printer components – A printer’s extruder and other components should follow a consistent mechanical path to produce parts. Sensors monitor this path as any variations could indicate an attack.
• Detection of nanorods in finished components – Using Raman spectroscopy and computed tomography (CT), researchers can detect the location of gold nanorods mixed with the filament materia. Variations from the expected location of those particles could indicate a quality problem, malicious activity, or efforts to conserve printer materials.

Researchers tested their technique on different 3D printers and a computer numerical control (CNC) machine using a knee prosthesis, proving the feasibility of the approach. Researches plan to improve their validation method to move closer to real application use. While there will be challenges to overcome – such as obtaining good acoustic data in noisy environments – researchers are continuing to develop steps to improve the security of 3D-printed parts. So, until this is market ready, how are you working to prevent malicious attacks on your AM/3DP systems? ~Elizabeth