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Workshop Themes HOW TO DEFINE LOW VOLUME Two recurring question at the workshop were, How do we define low-volume production? and When would a manufacturer consider itself in the low-volume re- gime? At various points in the workshop, participants noted that variable-demand manufacturing and high-mix manufacturing should be included in the definition of low-volume manufacturing. The discussion on how to define low volume began in the presentation by Dr. Schafrik, who gave Dr. Carlson’s slide presentation. In their presentation, Dr. Schafrik showed an example of a fuel nozzle made at GE Aviation via additive manufacturing. The total production would support on the order of several thou- sand engines per year for 20-30 years, with tens of fuel nozzles per engine—in other words, a total of between one and two million fuel nozzles. Dr. Schafrik considers this low volume, especially given that many machines are required to produce this number; more production is accomplished by adding more additive machines.1 Some at the workshop concurred that this a low-volume part, while others did not. More broadly, participants then pointed out that low-volume manufacturing is characterized not by a production number, but rather by certain overarching, general characteristics. These characteristics were later discussed by two presenters, Dr. Gupta, STPI, and Mr. Schneider, Key Tech. 1Additive machines are used here in the context of 3D-printers that add material rather than ma- chines such as lathes that remove material. 4

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Workshop Themes 5 In her presentation, Dr. Gupta explained that low-volume manufacturing is used for prototyping, for complex or customized products, and for high-mix, low- volume production. It typically needs short product development and prototyping times, and it must be flexible (so that multiple product designs can use the same tooling and equipment) and agile (so that process flow can switch among different product designs). During his presentation, Mr. Schneider, Key Tech, was also asked for his defini- tion of low-volume production. He responded that he considers a project to be low volume when nonrecurring engineering (NRE) costs become a large portion of the overall product cost. He said that another criterion for defining the low-volume manufacturing regime is when a standard manufacturer is unwilling to partner with Key Tech to make a product because it is not economically feasible for the standard manufacturer. The workshop discussion also considered variable-rate manufacturing and high-mix manufacturing, both aspects of low-volume manufacturing. Workshop participants pointed out that the Department of Defense (DOD) is interested in rate-independent production more than in low-volume production. Participants noted that the workshop was in fact more focused on responding to the needs of variable demand than to the needs of low volume. A participant stated that DOD would like to see the same cost per unit rather than having the costs scale dramatically depending upon the production volume. In other words, efficient, cost-effective, variable-rate production is a key driver for DOD. It was also noted that there is a need for a multiskilled workforce that could handle this type of flexibility. Having such a workforce is important to address high mix in a cost- effective, viable manner. In the question-and-answer period that followed the presentation of Mr. Ritchie, of the Tempus Institute, Dr. Latiff, of Latiff Associates, commented that the dis- cussion of quick-response manufacturing (QRM) seemed to focus on efficient manufacturing, not variable-rate or low-volume manufacturing. He asked how this fits into the framework of low-volume manufacturing. Mr. Ritchie explained that one-off manufacturing needs to be efficient, in terms of controlling total time. REDUCING THE COST OF LOW-VOLUME PRODUCTION One of the challenges associated with low-volume production is that it typically involves high cost. Several of the speakers addressed various ways to mitigate costs. Mr. Ritchie’s talk focused extensively on how QRM focuses on reducing total lead time, which reduces total cost. He explained that QRM is a strategy that introduces specific techniques to reduce total lead time, not just eliminate direct cost. He said that QRM concepts apply throughout the enterprise, with most of the improve- ment in time savings among up-front office applications. To actually reduce cost

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6 Limited Affordable Low-Volume Manufacturing and meet schedule requirements, Mr. Ritchie said, one must focus on reducing total lead time. He pointed out that everybody wins under this strategy: Both end users and suppliers benefit from faster deliveries as well as cost reductions. In his talk, Mr. Schneider addressed what could be done to reduce the time and costs to produce tooling for injection molding in low-volume applications. Mr. Schneider said that molds can be made in about a week for a few thousand dollars, much less than in the past. He suggested that there are two primary ways for costs to continue to decrease: • Use generic components. It is best to start with standard molds and mold designs and modify them accordingly. One can trade feature flexibility against cost and time savings. • Increase automation. Use software-generated quoting and designs, increas- ing the use of data-driven three-dimensional (3D) models and automating the mold manufacturing process. Mr. Schneider said there are companies emerging in the United States and globally that are very competitive in producing low-cost injection molding tooling, which is a real game changer.2 ACCESS TO RAW MATERIALS Access to raw materials was addressed several times by workshop participants, primarily in the context of additive manufacturing. Kenan Jarboe, Athena Alliance, said that the new manufacturing paradigm would include localized production— three-dimension printing at home, for instance. However, he pointed out that ac- cess to raw materials can be difficult, so a regional printing site better fits this new paradigm than home printing; Dr. Jarboe gave the example of a local hardware store printing individual screws in response to customer needs. Dr. Jarboe also brought up the idea of a power shift from the production site to the raw materials site. As this happens, control of raw materials becomes increas- ingly important. The International Traffic in Arms Regulations (ITAR) are not relevant when the design can be sent anywhere in the world and the parts manu- factured additively there. A workshop participant pointed out that critical data are protected by ITAR as well. Dr. Jarboe replied that ITAR may not be effectively enforceable, however. Workshop participants also noted that when the power shifts to the raw materials side, there can be bottlenecks or chokeholds from the material 2Companies such as Protomold make high-quality prototypes and returns parts in as few as 3 days for relatively little cost. There are also overseas companies, such as Model Solution, in Korea, that are very competitive.

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Workshop Themes 7 suppliers. Dr. Jarboe pointed out that a range of materials might need to be kept on-site for production. He likened it to a paint shop, where the different materi- als are like the paint pigments. The paint color is custom-mixed from a formula. Likewise, a manufactured piece could be custom-made from the different materials. During the Schafrik/Carlson presentation, Dr. Schafrik also briefly noted the importance of controlling the input metallic materials used for additive manufacturing.3 IMPROVING THE EASE OF LOW-VOLUME MANUFACTURING The workshop also included discussions of possible methods to make low- volume manufacturing easier. This discussion centered on three topics: (1) automa- tion; (2) advanced data packages; and (3) modeling and simulation. Dr. Schafrik noted in his presentation that in the long term (2018 and beyond), there will be increased focus on the development of best practices and the use of automation. Mr. Schneider noted that increasing automation is an important way to improve ef- ficiency. He suggested using software-generated quoting and designs, increasing the use of data-driven 3D models, and automating the mold manufacturing process. Other participants noted that using advanced data packages was a way to im- prove the efficiency of low-volume manufacturing. A DOD participant commented that industry seems to be moving away from using annotated two-dimensional (2D) drawings or even 3D renderings and instead is using the part itself. He said that DOD is wrestling with how to move forward without needing annotated 2D drawings. The low-volume manufacturing state of the art has so much informa- tion in the 3D tech data package that it may be simpler and cheaper to use the part rather than the data package. In the final discussion period, one participant noted that there are many ways to make low-volume production easier, including the use of advanced data packages. He pointed out, however, that there are many policy impediments as well. Dr. Ritchie said that it is important for companies to learn to manage policy-related issues.4 Dr. Gupta’s presentation focused heavily on modeling and simulation tools to benefit low-volume manufacturing through very large cost reductions, lowered design cycle times, improved efficiency, and enhanced performance. To enhance access to the high-performance computing required for manufacturing modeling and simulation, she emphasized the need for the following: 3Here additive manufacturing refers to manufacturing processes that add material rather than remove material to produce the final item. 4Policy-related issues can, for example, be requirements for qualification and testing of products before use.

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8 Limited Affordable Low-Volume Manufacturing • Better usage patterns for shared access to high-performance computing, • Customized simulation tools for specific applications in different engineer- ing communities, and • Open-source, integrated, dynamic models. INCORPORATION OF COMMERCIAL OFF-THE-SHELF TECHNOLOGY AND COMMERCIAL MANUFACTURING Incorporating COTS technology into DOD systems was repeatedly discussed at the workshop. Participants discussed how the use of COTS parts could improve efficiency and decrease costs, though there are barriers to their inclusion. The presentation of David Johnson, Wright Patterson Air Force Base, focused on improving the reliability of electronics parts. He suggested that certain circuit locations be flagged to note critical parameters that should be controlled more closely than what is in the part specification. These parameters should be docu- mented and monitored with testing. This would give confidence that the system will work the first time used, and with high reliability. Dr. Latiff asked if Mr. Johnson would propose a change to military specifications on how parts are designed and built. Mr. Johnson said no, that he does not want to redesign parts. He is addressing design practices at the circuit board and above—COTS parts that, when included in systems, create instabilities. Michael McGrath (ANSER) also focused on COTS technology and commercial manufacturing, summarizing the results of the decade-old NRC study Equipping Tomorrow’s Military Force: Integration of Commercial and Military Manufacturing in 2010 and Beyond (NRC, 2002) on the integration of commercial and military man- ufacturing. His talk summarized a number of ideas to improve that integration: • Implement policies, incentives, and guidelines for integrating commercial and military manufacturing. • Contract for life-support and technology refreshment. • Establish a commercial acquisition academy at the Defense Acquisition University to augment training and education. • Fund and execute rapid-response demonstration programs to build a broad integrated computational materials for engineering (ICME) experi- ence base. • Create mechanisms to increase awareness of future commercial technology and capabilities. • Invest in research and development to increase the mutual compatibility of military operating environments and commercially produced components in order to mitigate technical barriers.

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Workshop Themes 9 The NRC report summarized by Dr. McGrath stated that there are opportuni- ties at the system, subsystem, and component level for using commercial technol- ogy in military systems. Opportunities increase as one moves down to the com- ponent level. It is rare that a commercial product could replace a military system. Dr. McGrath explained that the military acquisition spectrum tends to work at the two ends of the spectrum—purely military manufacturing or purely commercial off-the-shelf technology. Mr. Schneider also discussed the use of commercial technologies. He touched on the idea of mass customization, where one can take low-volume principles to tweak an item that comes off of the line of a high-volume process. This allows for a wider variety of products at a lower cost. He also mentioned using generic COTS parts and customizing them as necessary as a means to minimize overall costs. PROCESS QUALIFICATION AND PRODUCT CERTIFICATION Process qualification and part certification were frequently discussed as constraints to low-volume manufacturing. Several participants noted the chal- lenges associated with certifying parts made via additive manufacturing. During Dr. Schafrik’s talk, a participant asked if direct digital manufacturing could be used for replacement parts for engines. Dr. Schafrik said that qualification of the part becomes a challenge. Another participant noted that the Federal Aviation Administration has ongoing work in the certification of airline parts that have an additive manufacturing component. During Mr. Schneider’s talk, a participant asked if the recertification was neces- sary if any changes were made for production. Mr. Schneider said recertification would be needed for Food and Drug Administration (IEC 60601) safety testing but perhaps not for clinical trials if it could be documented that the changes would not have an effect on the results. The participant noted that, because of this, manufac- turing partners should probably be brought into the project before FDA testing. He agreed that the manufacturer should be brought in early, though sometimes the manufacturer is not identified prior to FDA testing. RELATIONSHIP BETWEEN ADDITIVE MANUFACTURING AND LOW-VOLUME PRODUCTION Several workshop presentations focused on additive manufacturing,5 and there was much discussion of the interrelationship between additive manufacturing and low-volume manufacturing. A participant noted that additive manufacturing 5Here, additive manufacturing refers to manufacturing processes that add material rather than remove material to produce the final item.

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10 Limited Affordable Low-Volume Manufacturing has often been equated with low volume, but that is not necessarily true: Additive manufacturing can be a useful tool in certain applications but is not intrinsically the solution for all low-volume applications. Dr. Jarboe discussed additive manufacturing as a disruptive technology, with two main characteristics: It allows for something new (not just an improvement on something already in existence), and it has spillover effects that create new activities. He pointed out that additive manufacturing is a perfect example of a disruptive technology based on this definition. First, additive manufacturing began as a technique for rapid prototyping, but it has evolved to enable 1. Manufacturing new shapes that could not be manufactured before. For exam- ple, additive manufacturing techniques can create prosthetics that would have been prohibitively expensive using conventional techniques. 2. Harnessing the new use of materials. Additive manufacturing can combine materials in ways that were not possible before—for example, making a single piece of variable density. Dr. Jarboe imagined a baseball bat made with variable density (hard at one end, soft at the other). Dr. Jarboe explained that once the materials have changed, the design process needs to change as well, and this causes a completely different approach to manufacturing. This is a hallmark of a disruptive technology. Second, Dr. Jarboe noted that additive manufacturing has several spillover effects: • Additive manufacturing is based on knowledge, not assets. As a result, the manufacturing approaches change: Manufacturing can now be accom- plished anywhere there is a printer. • The economic structure changes. Manufacturing and service are now fused together. • The innovation model changes. Manufacturing becomes more bottom-up. • Additive manufacturing enables a new step in globalization, which is local- ized production within the larger global context. One participant asked if this globalization step could occur without additive manufacturing. Dr. Jarboe responded that as additive manufacturing technologies improve, the technique will replace traditional tools in the same local geographic location(s). During the question-and-answer period, a participant pointed out that there is a long way to go before additively manufactured parts are considered reliable and durable. Dr. Jarboe said that not only does additive manufacturing create more op-

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Workshop Themes 11 tions geographically, but also it allows flexibility for hybridizing. Some components can be produced additively, others subtractively. Another participant pointed out that additive manufacturing is at a crossroads, and if the technique is not picked up soon, it will remain only a niche application. The community is still in search of that big application. Dr. Jarboe responded that this is true, there is no “killer app” right now. However, hobbyists are making inroads to develop important products. He mentioned underwater robotics again as a good example. He thought perhaps hobbyists could enlarge their business, or perhaps the hardware store model might prove successful. Dr. Schafrik discussed many issues in additive manufacturing that still must be addressed, including • Surface finish, • Modeling tools, • Diversifying input raw materials, • Improving feeding mechanisms, • Developing more consistent energy sources, • Developing industry standards, including common terminology, • Increased sophistication of additive process equipment, • Improving design practices to take advantage of direct digital manufactur- ing capabilities, • Development of the capacity to produce more complex shapes, and • Inspection and qualification techniques.