In 2015, a startup called Voxel8 wowed attendees at CES in Las Vegas with a desktop 3D printer capable of 3D printing electronic circuits into thermoplastic parts. The firm demoed its Developer’s Kit system by fabricating a quadcopter live at CES and flying it directly off of the print bed.
Though Voxel8 continued to make announcements, mostly related to the sales of its Developer’s Kit 3D printer, for some time after that, it soon went radio silent. We did catch a brief discussion by the company at AMUG in 2017, but it wasn’t until just this past October that it made its first big announcement in years: Voxel8 has created a system for 3D printing shoe uppers.
To help the company along in its development of a machine capable of 3D printing 350,000 pairs of shoe uppers per year, DSM Venturing, along with the venture arm of HP Inc., have invested in Voxel8. To learn more, we spoke to Voxel8 CEO and co-founder Travis Busbee.
3D Printing Shoes
3D printing footwear components or even complete shoes has been an active area for some time, with New Balance working to additively manufacture midsoles years ago. Now, nearly every major athletic shoe brand is working to 3D print midsoles, including Adidas with Carbon, New Balance with Formlabs and 3D Systems, Under Armour, and Nike. Insoles, too, have become an area of active interest, with both startups like Wiivv and giants like HP participating.
What has been more difficult, however, is 3D printing the actual uppers of shoes, where all of the aesthetic appeal is and the bit that actually makes the shoe wearable. A startup called Feetz once tried to tackle this terrain using fused deposition modeling-style 3D printing, but it seems to have gone defunct in late 2018.
Busbee thinks his company can succeed where others have been unable to.
“These footwear brands are really looking for an automated digital supply chain to allow them to get their products to market much more quickly and to do so without extravagant tooling costs,” he said. “That way, they can introduce small batches of products to market, analyze the demand and then respond to it in real time. Ultimately, in order to get there, they have to have a solution for both the top and the bottom of the shoe. Currently, they only have a digital solution for the bottom, but no one has come up with a solution for the top until we came around and created this solution specifically tailored to address the top portion of the shoe.”
The Active Lab Digital Fabrication System
Currently, shoe uppers are made using a labor- and material-intensive process that includes die cutting, tooling, stitching, finishing, gluing and assembling components. Voxel8 has developed a method for automating and streamlining the fabrication of uppers via 3D printing.
“If you just took a piece of textile and sewed it into the shape of a shoe, you wouldn’t have enough structure to really have the shoe stand up and look good and keep your foot centered on the cushioning elements of the shoe. You wouldn’t have any logos or text or branding,” Busbee said. “Ultimately, the things that go on top of that textile create the structure that give the shoe its functional performance and also create the design language and style or at least play a huge role in it.All of those components that go on top of the shoe are the parts that are the most difficult to make.”
Using a multi-input active mixing printhead, Voxel8’s Active Lab Digital Fabrication Systemis capable of either spraying or extruding liquid polyurethane elastomers onto a textile that then solidify as the elastomer reacts. This gives structure to the otherwise two-dimensional and flimsy fabric, allowing it to become a three-dimensional cloth.
While the extrusion nozzle may be used to build up 3D structures similar to FDM-style 3D printing, a spray nozzle enables conformal coatings on top of textiles or the ability to actually penetrate the textile to add a significant amount of support without adding too much weight. Though the print nozzles described above can be swapped out manually in about 30 seconds, Voxel8 is working on automating this feature in the near future.
Key to the technology is the active mixing printhead, which makes it possible to tune the composition of the elastomers on the fly. In turn, the system can change the material properties of a given region, making it soft and stretchy like a rubber band in one area and more rigid and supportive in another.
Additionally, an inkjet head, similar to what might be found in a traditional 2D printer, provides digital coloration into the polyurethane and the fabric itself.
“We’re basically putting a pigment into this polyurethane using an inkjet process,” Busbee said. “That gives us photo-quality control of color inside of the digitally tunable material property structures.”
Whereas the Active Lab system is meant for product development, wear testing and limited production runs of athletic footwear, the company is developing what it calls the ActivePro system, meant for volume production of 350,000 pairs of shoes per year per system. This, Busbee believes, will be ready by the end of 2020.
Once it is released, shoe manufacturers may be able to overcome a number of obstacles. Time to market, according to Busbee, is key for large athletic footwear brands because it currently takes about 12 to 18 months from the time a shoe is designed to when it makes it onto shelves. Moreover, the mass manufacturing paradigm requires that these companies anticipate what the demand will be for a given design and produce hundreds of thousands if not millions of those designs. By the time the product is on the market, fashion trends may have already changed significantly from the time the item was conceived.
On-demand manufacturing, the goal of a large majority of 3D printing-focused businesses, could theoretically put an end to excessive waste due to inventory overstocking. If distributed properly, it could even reduce greenhouse gas emissions associated with shipping and reshore manufacturing jobs currently being performed by underpaid laborers, often children, in third-world countries at the behest of some of the brands discussed in this article and more.
Voxel8’s Evolution
Born out of the multi-material additive manufacturing (AM) research being performed under Harvard professor Jennifer Lewis, Voxel8 spun out of Harvard with the goal of commercializing Lewis’s research. Among the verticals being explored within the lab was 3D electronics printing. To test the commercial possibilities of 3D electronics printing, the startup released the Developer’s Kit, hoping that its customers might find a killer application for the technology.
“We had a ton of inbound interest from major Fortune 500 companies that were interested in exploring aspects of that technology. As a result of that, we anticipated that electronics printing would be where we would find this killer application,” Busbee said.“We built and shipped over 100 of these to many Fortune 500 companies across the world. Ultimately, we meant for it to be a market discovery tool where we would get it into the hands of customers and work with them to figure out what problems they were trying to solve and essentially how we could develop a next generation product that would enable them to solve their real problems in volume production.”
Among the parties that took an interest in the Developer’s Kit was the MITRE Corporation, which manages federally funded research and development centers for such federal agencies as the Department of Defense and Department of Homeland Security. Using Voxel8’s technology, the non-profit developed a low-profile, wideband phased-array antenna for the U.S. military. The benefit of this type of antenna was that it, unlike reflector dishes, does not have to be pointed at a signal to receive it and can capture a broad range of signals without moving.
MITRE team members were able to 3D print a prototype of this complex antenna design to determine that it was feasible. Though Voxel8 has shifted its public focus to consumer goods, MITRE was able to purchase a customized Developer’s Kit system with more capability.
Voxel8 had another U.S. government connection via In-Q-Tel, the venture capital arm of the CIA, which participated in a $12 million Series A funding round for the startup. Its interest in the technology was obviously not disclosed. Of the investment, a Voxel8 Technical Support Engineer told CrunchBase, “In In-Q-Tel’s [IQT] case, I can mention that their requests aided us in the development of the Voxel8 Developer’s Kit 3D Printer. IQT was interested in specific capabilities that we provided through the DK units, and their funding aided us in bringing this product to market. As you may have noticed, we have since discontinued the DK (due to further development), and I cannot comment on current IQT relations.”
Ultimately, these developments related to 3D electronics printing were purportedly shelved in favor of developing the ActiveLab series. Along the way, Jennifer Lewis, formerly the CEO of the startup, took an advisory role so that she could continue to teach and manage her Harvard lab.
“There’s still a lot of potential in the 3D electronics printing market,” Busbee said, “but, really for us, the level of potential in athletic footwear uppers exceeded the potential that we saw in the short-term in electronics.”
Busbee did not confirm, but one can assume that because the capabilities for 3D electronics printing still exists within Voxel8, it’s not out of the question that wearable electronics might someday emerge from the startup. In fact, if you combine its experience with MITRE, you might even imagine wearable electronic antennas being developed behind closed doors.
For Voxel8, however, the focus is on athletic footwear before the company ventures into other athletic wear and possibly even medical devices. To help spur them along is the Series B investment recently led by DSM Venturing, with participation from HP Tech Ventures and existing investors Braemar Energy Ventures and ARCH Venture Partners.
DSM is the Dutch materials company that has quickly been increasing its presence in 3D printing. Interestingly, it was HP’s 2D printing team that took an interest in Voxel8, likely for the inkjet capabilities of the startup’s technology.
To learn more about the firm, visit the Voxel8 website.