Imagine a worker being able to print specialized parts while on a construction site, or a mechanic being able to manufacture a replacement for a faulty engine part with the click of a few buttons. Sound like science fiction? Maybe, but these scenarios are rapidly becoming the new reality thanks to additive manufacturing (AM).
AM—a technology that builds 3D objects by adding layer upon layer of material regardless of whether that material is plastic, metal, concrete, or even human tissue—is fundamentally changing how companies manufacture, distribute, and maintain products. Because AM allows parts to be manufactured at the place and time of need, more and more companies are moving toward a decentralized manufacturing model freed from its traditional geographical restraints.
This shift dramatically alters the nature of supply chains, by replacing traditional networks consisting of a few original equipment manufacturers (OEMs) and suppliers with vast ecosystems of potential manufacturers and subcontractors. It also makes supply chains increasingly dynamic and offers requestors/customers a convenient source of supply. Product lifecycles are significantly shorter, while ramp-up and ramp-down periods are more intense.
Yet while additive manufacturing offers all of these benefits, it does not come without added risk. The digital nature of the AM supply chain can also make it more vulnerable to cyberattacks, counterfeiting, and tampering. The answer to these concerns may lie in another new innovative technology: blockchain.
A growing risk
Even in its more traditional format, manufacturing is one of the most targeted sectors for cyberattacks. A recent study by LNS Research indicates that more than half of the manufacturers participating in the survey experienced cyber-security breaches over the past year.1 These attacks are usually focused on industrial control systems at manufacturing sites and machines.
AM provides cyber criminals with a new potential target: the parts themselves—or more specifically, their "digital twin," a digital file that contains the parts' specs and manufacturing instructions. That's because the effectiveness of AM depends almost entirely on the integrity of digital files to tell the 3D printing mechanism what to do. Quite simply, the finished state of the printed item can only be as good as the digital instructions the printer receives to manufacture it. As a result, the delivery and security of those digital files is paramount.
Additive manufacturing increases not only the importance of digital files but also the number of organizations receiving highly sensitive product data. In the traditional manufacturing model, the company that creates the design files would also handle manufacturing and then shipping of the final product. In the AM supply chain, however, this is no longer the case. In an AM ecosystem, numerous product variations move through multiple parties, all of which are attempting to coordinate work together. All of these transmissions could be compromised or hacked, and the design files could fall into unauthorized hands and/or be used to create counterfeit, maliciously modified, or uncertified parts.
The power and potential of blockchain
To ensure the integrity and traceability of digital files and assure their secure delivery at each stage in the supply chain—from the file developer all the way to the end user—more companies are turning to blockchain. Blockchain functions like a distributed database that maintains a continuously growing list of ordered records ("blocks"). Because blockchains time stamp each record and link it to a previous block, they are inherently resistant to modifications of data.Â Â Â Â Â Â Â Â Â
Blockchain works by storing information (such as design files) across each phase of the digital supply chain—design, distribution, manufacturing, and in-field—on participating nodes. A node is any electronic device connected to the blockchain network that automatically downloads and stores a copy of the blockchain. All transactions (such as the transfer of a file from one entity to another or a modification to a design file) within a block of data are cryptographically hashed (or given a unique digital fingerprint) along with the previous block to form the current block. As a result, any data modifications would result in a new digital fingerprint and—since the blockchain network is governed by consensus—the authenticity of any transaction can be rejected as fraudulent.
Bottom line? While blockchain technology has taken on many different forms and has had many distinct applications, the underlying concept of all blockchain-based systems is similar. While blockchain does not directly keep the data it transmits secure, it does have the ability to indicate when files have been tampered with and to expose when a file has been corrupted.
So, if an additive manufacturing supply chain implemented blockchain at the transactional node level, it would assure that all assets were traceable and their provenance known and that users could see the full lifecycle of the part.Without blockchain, security relies on encryption alone, and there is no way to really determine if a digital file has been corrupted. Blockchain grants authenticity by exposing if a file has been corrupted or changed.
To be effective, though, it is essential to secure supply chain data at each phase of the AM digital supply chain. This begins with the design phase, where both the final design of the part and all of its associated engineering data need to be considered highly valued assets that require protection. Securing supply chain data could require file encryption, digital licenses and smart contracts, and digital references as well as the use of blockchain.
By encrypting the design files, part designers ensure that only authorized users will have access to the information enclosed. Doing so blocks access to the design files until they are decrypted by a designated AM machine. A smart contract then acts as a licensing mechanism, that will allow the owner of the intellectual property to define who can have access to that data, for what length of time, and how and where that data is to be used in manufacturing the part.
In the traditional manufacturing model, the company that creates the design files would also handle manufacturing and then shipping. In the AM supply chain, however, this is no longer the case. Instead the parts designer transmits the encrypted design files—along with an accompanying digital license—to downstream companies that are part of the supply chain via email, an offline system, or direct access to the company's server from one system to another, depending on the level of security measures required.
Given the potential for such measures to be compromised, using a smart contract-enabled blockchain here is essential. Doing so allows the digital distribution license to be authenticated, transported, and recorded by blockchain transactions. It also enables all members of the blockchain to participate in and substantiate design data provenance, while simultaneously enforcing the distribution and asset management rules set by the smart contract.
Engineers can also use blockchain to apply business and production rules to the encrypted design files that will specify the make and model of the machine allowed to execute the design, the types of build materials permitted, and various other build parameters. Manufacturers will only be able to decrypt the design files once these specifications are met. Moreover, production rules will control the number of parts each manufacturer is licensed to print. This ensures quality standards are met and prevents counterfeits from being made on authorized equipment. Additionally, the blockchain ledger will track and store all events associated with the lifecycle of the part design so the provenance of each part can be verified and any errors detected in end products can be traced to their source.
Finally, when a physical part is manufactured, it should be tagged with a digital reference and recorded in the blockchain ledger. For example, parts could be coded with a chemical tracker, radio frequency identification tag, or serialization number that can then be matched to information stored in the digital ledger. Doing so provides a link between the digital and physical thread that can be used to trace any part back to its manufacturer, the machine that created it, the conditions under which it was created, and the original design creator. The blockchain ledger can also be used for performance modeling, failure simulation, and overall performance improvement of a specific part.
"An elegant solution"
As more industries realize the benefits of AM, it will become important for companies to recognize that the products of AM are only as viable as the integrity of the digital files and the printers that create them. Clearly, securing the digital supply chain with blockchain technology is critical. Blockchain serves as a hedge against lost revenue caused by intellectual property (IP) theft.
For manufacturers in the government and military space, the benefits go even beyond protecting against IP theft, as counterfeit parts could threaten safety and national security. The Department of Defense (DoD) named supply chain integrity and counterfeit parts as two of its top concerns for the electronics sector in its Fiscal Year 2017 Annual Defense Industrial Capabilities Report.
According to the DoD report, one of the key reasons that counterfeit parts enter the supply chain is technological obsolescence, where the equipment is no longer manufactured by the OEM and must then be purchased from third party. According to the DoD report, between 50 percent and 80 percent of suspected counterfeit parts were for obsolete equipment at the time of discovery.
One of the benefits of AM in the defense space is that it allows suppliers to store designs for replacement parts that OEMs have stopped manufacturing and produce them on the spot. Blockchain can validate that suppliers are using the correct design file.
For these reasons, the Department of Defense is very interested in the potential of blockchain to be used in AM supply chains. "Blockchain is an elegant solution," said Steven Dobesh, Commander, U.S. Navy, Technology & Innovation Branch Chief, Joint Chiefs of Staff-J4.Â "It will address the concerns of securing the digital thread of AM. I think it is the best answer to the important issue of traceability and provenance. We must have the same level of confidence when we pull a part off the printer that we currently have when we pull a physical part off the shelf. Blockchain will help us to achieve this through an append-only immutable ledger of transactions."
With any new technology comes disruptions to culture, thinking, and the supply chain. Additive manufacturing paired with blockchain technology is just this kind of disruption. While best practices for securing and authenticating data and ultimately improving the digital supply chain through blockchain-enabled security solutions still need to be determined, blockchain technology undoubtedly holds the key to counterfeit mitigation, data integrity, compliance rights, and feedback monitoring.
In the end, incorporating blockchain into the manufacturing cycle will lead to faster production by accelerating time to market and reducing physical storage requirements. This will enable additive manufacturing to live up to its full potential.
1. Matthew Littlefield, Putting Industrial Cyber Security at the Top of the CEO Agenda,Â LNS Research and Honeywell, 2017.