Designing 3D-printed foams is challenging. A range of variables must be addressed to control performance and function of these lattice structures, including size, shape, and direction of struts; geometry voids; and material, which can make engineering a digital foam expensive and time-consuming.
EOS’ Digital Foam changes this so designers can make groups of cells, creating a lattice that can be engineered with varying levels of compressibility. Applications range from protective headgear to prosthetics, insoles, and more. The material is well suited for any generatively 3D-printed object with a flexible grid-like structure or matrix, composed of open cells joined together by differing characteristics – any varying 3D-printed lattice structures morphing into each other.
“Using polymer materials, such as TPU or PA 11, you can really tune foam characteristics to the individual application,” says Fabian Krauss, EOS’ global key account manager. “Often when you hear foam you think spongy, elastic, and soft, but there are also rigid foams, such as those used in prosthetics or bicycle helmets.”
EOS’ Global Medical Business Development Manager Laura Gilmour explains this “lattice approach differs from the rigid, porous, or lattice structures medical device companies have been using for more than a decade to create surfaces for in-growth bone, such as with some orthopedic implants.”
Digital Foam is more than a 3D-printed adaptable grid. EOS’ Digital Foam program connects CAD, materials, part qualification, and additive manufacturing (AM) to accelerate implementation of new ideas and delivery to end users.
“We’re not often making new products, we’re enhancing them, personalizing them,” Krauss says. “Because we can tune the foam element to the patient and the specific need, companies are able to personalize and enhance products in a more cost-effective way.”
Krauss explains the real impact of the patent is that the component consists of various structures, which are then 3D printed, a core piece to many applications. “So, you can take a scan of a patient and make a lattice structure, but as soon as you want to customize it, you’re varying that lattice structure and that’s when our patent is so valuable.”
While Digital Foam is a relatively new technology, advanced software developments have moved it to a more friendly process.
When asked what other areas of medical use Gilmour sees for Digital Foam, she mentions diabetic patients and “a lot of really great applications to relieve pressure points” that can provide the right stiffness or softness required.
“In my opinion, the easiest pathway for a customer to try this is on a new product, not taking a CAD file for subtractive and applying it to AM,” Gilmour says, “So, for those interested in learning how this can be used in new or existing products, EOS’ Additive Minds group helps customers apply the technology very specifically to their situation.”