Issue link: https://wardsworld.wardsci.com/i/1507671
6 3D Printing (continued) + ward ' s science iMaterialize; customers can order 3D prints online and receive them by mail. On C2C, 3D Hubs is connecting 3D printing users and owners worldwide, such that anyone can use a 3D printer without owning one. On the B2B side, there are a few 3D-print- ing solution providers for businesses, such as 3D Systems and Stratasys. Customers Customers span across many industries. Because of its capabili- ty to produce highly complicated customized parts, 3D printing has been widely adopted in aerospace and defense, healthcare, entertainment, and jewelry industries, in which customized parts are needed in low volume. As the cost of 3D printing has come down, it has gained more users in education, consumer, automotive, energy, and other industries. The open-source community The open-source community is a very important part of the 3D printing industry. Two popular open-source projects, RepRap and Fab@Home, were started around 2006 and have fueled public interest in 3D printing and the worldwide maker move- ment. Although the Fab@Home project is no longer active, the RepRap project has catalyzed hundreds of 3D-printing-related start-up companies. Stratasys and Ultimaker were two of the most successful examples. Most importantly, the open-source projects provide precious learning opportunities and resources for new generations of 3D-printing enthusiasts. Outlook McKinsey Company predicts that 3D printing could have an economic impact of U.S. $200–500 billion annually by 2025, with 5–10% of all products worldwide being 3D printed, which would bring massive opportunities and challenges. Opportunities Touted as the technology that will lead the next industrial revo- lution, 3D printing fundamentally changes how we produce, which will lead to drastic changes in product designs and busi- ness models. Product design Limited by traditional manufacturing, the majority of existing products have suboptimal designs. 3D printing will enable new product designs in three different ways: complex geometry, material composition, and 4D structures. Complex geometry will enable optimization of the physics. For example, lattice structure can be used to optimize the strength-to-weight ratio. GE used complex internal geometry in its LEAP engine nozzle design to optimize fluid dynamics and improve fuel efficiency. Allowing precise control of the material composition provides the flexibility to easily change properties at different locations, which could significantly reduce the number of parts needed for a product and opens up possibilities of designing new meta-materials. 4D structures refer to dynamic structures that can respond to external stimuli to change their shape or functionality over time, by printing smart materials that respond to heat, electricity, or humidity. Such possibilities pro- vide opportunities to redesign almost every existing product for better performance. Business model 3D printing digitalizes the manufacturing process and makes it much easier to have generic decentralized manufacturing plants around the world, which provides opportunities to move the majority of the supply chain online. In the current model, a product is usually designed by professional designers, sent to a specialized factory for mass production, transported to a local distribution center, then to shopping centers where customers pick the products that are not designed specifically for them. In an alternative model, customers can design their own products with the help of easy-to-use professional design software and send the designs directly to a home printer or a local produc- tion center, where they can pick up the printed products. The generic decentralized manufacturing plants can serve as an infrastructure, which makes it possible for product developers to focus on product design without spending on managing a complex supply chain. The alternative model will significantly improve the efficiency of both product development and con- sumption. The AM3 Lab at the University of Arkansas is working on a vision of a generic digital manufacturing factory equipped with thousands of mobile 3D printing robots with different functionalities that work together to build different products autonomously (known as autonomous digital additive manu- facturing or ADAM). This vision is shown in Fig. 4. Challenges New technology has roadblocks, and 3D printing is no excep- tion. Three main challenges need to be overcome for 3D print- ing to become a true digital manufacturing infrastructure for our society: cost, quality, and design tools. Cost Because of the need to join material units bit by bit, 3D print- ing is currently slow compared to traditional mass production techniques, which makes it less cost-effective for high-volume production. Many solutions are being developed and have demonstrated great promise, such as the production system from Desktop Metal and the CLIP technology from Carbon.