Remember in CSI, when Gil Grissom and Catherine Willows would trace a photocopy back to a suspect’s house? Well, unlike some of their other techniques (cough enhancing images cough), it turns out that that’s actually plausible! At least, it is for 2D prints…

Now, thanks to a research team out of the University at Buffalo, NY, it’s also possible for 3D prints! Under the leadership of Wenyao Xu, an associate professor of computer science and engineering, the group has developed a 3D printer identification system that can physically link a 3D printed object to its source machine.

They tested their system, called PrinTracker, against 14 3D printers, 10 fused deposition modeling (FDM) devices and 4 stereolithography (SLA). Each machine was made to create five typical door keys, which were then analyzed for imperfections.

To begin, the team generated digital images of the keys using an inkjet scanner. Then, by applying multiple filters to the images, they were able to identify distinct variations. Interestingly, these corresponded to patterns that were similar within but not between sets of five keys. In other words, the printers were successfully shown to have unique “fingerprints”.

The fingerprints were identified using an algorithm that the team themselves developed. Their hope is that the technique could be applied to law enforcement, especially in the context of tracking illegally 3D printed objects like guns.

“3D printing has many wonderful uses, but it’s also a counterfeiter’s dream,” says Xu. “Even more concerning, it has the potential to make firearms more readily available to people who are not allowed to possess them.”