Counterfeit parts and materials pose a serious threat to the United States defense supply chain. The National Defense Authorization Act (NDAA) of 2012 (Section 818) laid out strict guidelines for DoD prime contractors for detection and avoidance of counterfeit electronic parts1. The Defense Logistics Agency (DLA) identified six federal supply groups in their supply chains that are at high risk for counterfeiting including electrical and electronic components, bearings, hardware and abrasives, pipes and fittings, engine accessories, and vehicle components2. DLA is championing development of anti-counterfeiting technologies that also provide traceability for the parts in its supply chain. A solution called QuanTEK developed by Chromo Logic LLC, involves novel optical imaging methods and has been found to work on a broad class of the DLA identified high-risk federal supply groups.
Concept of Operation
The QuanTEK system exploits the fundamental fact that all items exhibit unique, information-rich surface features as a consequence of the normal manufacturing process. These micron-scale surface features on each item, like a fingerprint or iris pattern used to authenticate humans, are highly random and impossible to forge or copy3. QuanTEK obtains these patterns with a non-contact imaging system and, using proprietary algorithms, tracks products back to an enrollment scan at an approved source to verify authenticity of the product.
As shown in Figure 1, the QuanTEK system consists of a camera system with built-in adaptive lighting/magnification, a raised base for placing the parts, a mini-PC for the control and image processing algorithms, and a tablet with a Graphical User Interface (GUI) to operate the system. The concept of operation is a two-step process. Step 1 consists of taking an optical image (noncontact) of the surface of the part in an enrollment scan carried out at the start of the supply chain, for example at an original component manufacturer or at an authorized distributor. This Step 1 may also occur at an independent distributor who complies with the appropriate provenance processes with the parts tested at an authorized test laboratory. From the enrollment scan, QuanTEK’s proprietary algorithms choose several regions of interest (ROI’s) in the image and convert those ROI’s into a first virtual tag or vTAG™ stored in a secure cloud database.
Step 2 occurs at the end of the supply chain where the user, the original equipment manufacturer, the depot, or the Services, takes a second optical image as a verification scan and generates a second vTAG for cloud storage. The two vTAGs are compared and if they match, the part is declared as secure. If there is no match for the second vTAG, the part is suspect.
As shown in Figure 1, the matches and non-matches are quantified by a metric called the normalized Hamming distance (NHD). In the case of a perfect match, all the ones and zeros of the two vTAGs will be identical, giving a normalized Hamming distance of zero. If there is a perfect non-match, on average half the bits will match and half of them will not match, giving a normalized Hamming distance of 0.5. In most real cases, the matches and the non-matches will fall within a slight distribution reflecting hardware noise and variation between units. An appropriate threshold setting is selected that gives low false positive and false negative rates, then a normalized Hamming distance below the threshold is declared as a match, and the normalized Hamming distance above it declared as a non-match.
The QuanTEK system parts handling capability is robust, is not affected by the material of the part and it performs in both dry and damp heat conditions, including thermal and humidity cycling. The system does not require any special treatment of the parts under test. More importantly, QuanTEK eliminates the need to mark a part – a process that could potentially violate its intellectual property or its function.
Multiple verifications can be carried out whenever a part changes custody establishing traceability of parts through the supply chain, and the database may also contain time/location stamps and other information.
Successful testing was done on commonly used washers with no identifiable external markings. Figure 2 shows an uncoated steel washer with results from tests consisting of ten such identical washers. All ten washers were enrolled using the QuanTEK system. Each enrolled washer was verified with itself, and the results showed a low NHD as represented by the blue bars. When any one of the enrolled washers was verified against any of the other nine washers, the results showed a high NHD represented by the red bars.
A level 2 test is done using the same QuanTEK unit but at different times with potentially different orientations, while a level 3 test represents two different QuanTEK units, one for enrollment and the second for verification. The results show negligible unit to unit differences and the separation in the average NHD values between the blue and red bars shows the ability to clearly differentiate between similar looking washers.
Comparing this result with an actual use case, if ten washers were enrolled at a manufacturer, and if somewhere in the supply chain, a few of those washers were removed and substituted with similar looking washers, then at a downstream verification point, the QuanTEK system would be able to correctly identify the similar looking unenrolled suspect washers. Similar successful results have been obtained for chrome plated washers, case hardened steel washers with blackoxide finish, and painted washers.