DARPA’s Atoms to Product (A2P) program is developing means such as microelectromechanical (MEM)-based manipulation for assembling nanometer- to micron-scale components into larger human-scale systems.
Materials Engineering (ICME). “The DARPA AIM program on the acceleration of materials technology is probably the single research program with the most impact on the field,” according to Dr. Greg Olson, Walter P. Murphy Professor of Materials Science and Engineering at Northwestern University and founder of a company based on computational materials science. “I see computational materials engineering as the greatest innovation in materials since the iron swords of the Hittites,” added Olson, referring to the anomalously early accomplishment of the Hittite culture to smelt iron some 3,800 years ago – while the world was still in the Bronze Age. Follow-on work beyond the AIM program, supported by both DARPA and the Navy, helped to establish 3-D characterization and simulation techniques for materials structure. The computational and simulation tools that emerged from these efforts made for a natural fit with DARPA’s championing of Solid Freeform Fabrication in the 1990s, a precursor of today’s rapidly advancing infrastructure of additive manufacturing and 3-D printing. “The adaptation of the AIM acceleration approach to 3-D printing technology to rapidly qualify 3-D printing technology is a tremendous advance,” Olson said, referring to the parallel need to certify the usability of 3-D parts in actual systems along with the ability to make the parts in the first place. With the growing ability to use 3-D printing to combine form and functions in ways that had not been possible before, said Vandenbrande, “we have opened up the design space significantly.” This ushers in another set of challenges, of course. 3-D printing provides the possibility of engineering the properties of each volumetric pixel, or voxel, of a part. The amount of data and computation required to do that is enormous. “What we need is a new set of maths and algorithms
that can describe materials and the shapes they comprise in one kind of cohesive way,” said Vandenbrande. Coming, he added, is the ability to design multiple functions – think here of aircraft skins that combine structural, sensing, cloaking, and antenna functions – in a fully integrated way. If materials engineers and manufacturers could master this exquisite degree of control over material structure, they could responsibly imagine such things as strong and featherweight aircraft made out of structural materials designed and grown to have massive amounts of empty interior space like the bones of birds. The current DARPA Atoms to Product (A2P) program, which is all about developing means for assembling nanometer- to micron-scale components into larger human-scale systems, heads in these directions. Which brings us full circle to Vandenbrande’s observations over a decade ago – and highlights the next great challenge that DARPA is taking on. Vandenbrande refers to this as solving “the inverse problem in design.” This is where the designers would first specify the performance values for a system and its parts – whether it is a missile, ground vehicle, or prosthetic limb – and hand those off to computational and modeling tools to generate multiple solutions that balance shape with the detailed material structures that could deliver the performance and functionality required by the design specifications. His current programs, Fundamental Design (FUN Design) and Transformative Design (TRADES), are developing the foundational mathematics and algorithms to initiate this vision. Vandenbrande envisions a time when computers become a true partner in design, capable of integrating advanced and emerging material architectures, to create systems currently unimaginable today – perhaps an aircraft additively built up of ultra-light micro-structures that resemble bird bones. When there is seamless integration of materials, design, and manufacturing, Vandenbrande will know that his vision has become reality.