combination of ultrasonic C-scan and finite element analysis (FEA) the defects were undetectable. What they discovered is that 3D printers are capable of either being intentionally or inadvertently instructed to create defects in products – meaning hackers could intentionally alter a print to ill effects or manufacturers could unintentionally do it themselves by adopting practices that result in products being printed in less than ideal conditions. According to the paper, these attacks could take the same form as hardware trojan attacks that go after the integrated circuit (IC) process chain, but would require very different defenses because of the small-batch nature of AM.
“These features may be introduced by several reasons which include undesired features in the STL file due to the gaps caused by the tessellation process, printer skipping a print step due to mechanical issues, or a hacker intentionally introducing a sub-detection limit feature to compromise the product quality,” according to the paper.
Explore The 3D Printing Revolution
Prior research, including as a study conducted by researchers at the University of California, Irvine as well as separate research done by the University at Buffalo have shown 3D printers can be hacked through various methods (including recording the acoustic waves made by the printer) to steal or replicate the design files the printer is using. For Gupta this, combined with his own research, represents a significant danger for AM. “If someone steals CAD files or files used for 3D printing there's nothing that stops people from reprinting those parts in very high quality,” Gupta said. “They can create a product as good as the original.
“The problem comes from two sides: There may be malicious persons or someone may counterfeit a product. And owners of the IP can't distinguish original from knock off.”
Securing 3D Printing
So what then are the solutions? Gupta said there is the possibility of using and creating new a better materials. However he said, “There are printing techniques that only work with certain materials. At this point AM is limited to using a certain variety of materials, so you have to look at a combination of materials and printing to tackle the problem.”
What about new detection methods? It's possible, but it might not be the most cost-effective solution. “ There are these methods that are already in line,” Gupta said. “Testing every product for every possibility of defect is very expensive. You can use something like a CT scan that will give more defects, but it's more expensive because of time and cost constraints.
“Testing methods we have now are optimized for traditional manufacturing methods so what we are thinking is these methods have to evolve and keep pace with 3D printing. There is no one solution that will work in all cases.