Reinventing the basketball: A conversation with the creators of 3D printing’s latest sporting innovation

The NBA All-Star Weekend brought over 4 million eyes to a 3D printed airless prototype basketball in February 2023. The AT&T Slam Dunk Contest, which took place on Saturday, February 18 at the Vivint Arena in Salt Lake City, Utah, was the stage for its debut as KJ Martin of the Houston Rockets took the basketball and dunked it through the hoop.

Wilson Sporting Goods worked with General Lattice for the computational design aspect of the project, EOS for the additive manufacturing stage, and DyeMansion for finishing and adding colour to the ball.

The topic rapidly became one of the most talked about stories in both the sports world and the 3D printing industry, although many people had the same question, does it actually bounce?

The answer is, yes, it does. It also nearly meets the exact performance specifications of a regulation basketball used in the NBA.

To find out how this was achieved, let’s take it back to the beginning. Five years ago, Dr. Nadine Lippa, Innovation Manager at Wilson Sporting Goods was given a daunting task by her boss, Kevin Krysiak, Senior Director of Global Product R&D and Supply Chain Innovation at Wilson: to ‘reinvent the basketball.’

“We started with several projects with that goal," Dr. Lippa told TCT about the early stages of the project. "One of the things we wanted to improve upon was inflation. Air pressure changes over time in different environments, hot or cold, needing other pieces of equipment like a pump or a needle. One of the ways to handle that is to make an airless ball.

Wilson Sporting Goods Co

Houston Rockets' player KJ Martin holding the 3D printed basketball.

“We felt 3D printing was a very interesting approach to do that, because you can take one material and vary the properties, you have the material properties and then you have the mechanical structure. There you basically have the two levers that you can pull. When you find the perfect combination of those, you can have something that responds in different ways, a ball that when you bounce it, it stays on the ground or a ball that returns to your hands. But I think what took us five years is that second piece, getting the ball to come back to our hands, also getting it to come back to your hands without it being very hard, very rigid, something that can withstand many fatigue cycles and doesn’t break very easily.”

To achieve this level of performance, the team at Wilson trialled different 3D printing methods, including resin 3D printing, power-based 3D printing, extrusion-based 3D printing, and eventually settled on selective laser sintering (SLS). According to Dr. Lippa, the self-supporting nature of SLS was 'really helpful.'

The specifications that the ball had to meet involved physical and durability attributes. The physical attributes included circumference in all directions, and more subjective attributes such as hand field play testing. Another physical attribute was rebound, and the ball was rebounded at different points, such as the poles of the ball versus a channel.

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Dr. Lippa said the ball also performed well in durability tests, the same ones any normal products from Wilson are subjected to, due to the material and mechanical combination it was tuned into.

Wilson Sporting Goods Co

Dr. Nadine Lippa (left) Innovation Manager at Wilson.

However, the project has been strictly confidential for the past five years, so the ball could not undergo the normal player testing that products typically go through to gain useful insights.

“It’s been in relatively few hands which made it a little bit more nerve-racking once we exposed it to the public," Dr. Lippa said. "One thing we didn’t anticipate was that so many people wouldn’t believe that it bounces. I saw so many people posting when they saw a still photo of it, being like ‘Yeah, that’s a cool model, but like, does it bounce?’ and that made me laugh, because that was really the whole project, making sure that it would bounce like a regular ball.

“The people that have put it in their hands have really had the most amazing reaction, where they’ll typically hand it to someone, and they’re just impressed by the structure and the fact it’s just so different looking than a conventional ball. Then inevitably, they will look at me and say, ‘Can I bounce it?’ and I’m like, ‘Yeah, of course you can bounce it.’ Then they bounce it and there is this look on the face of everyone who bounces the ball for the first time. They all make the same face, it’s this really awesome, child-like passion look in their eyes. That’s what makes me really excited about this project. I really feel like this, in addition to trying to solve this problem about inflation, is just reigniting people’s passion about the sport, which is a really awesome consequence of this work.”

In the selective player testing that has been done, Dr. Lippa highlighted how fun it was to see how players wanted to keep playing with it.

“We’ve given it to a couple teams after they were done with practice, just to see as we were getting ready for the dunk contest to see how it would dunk and if they had feedback," Dr. Lippa said. "People were really tired from practice, and you could tell they were just ready to go home for the day, but as soon as they started playing with this ball, it was like they were re-energised. It was like watching a bunch of little kids run around on the court, trying all different things with the ball, that was really special.”

Dr. Lippa spoke to TCT about the possibility of this same process being used for balls in other sports, such as football (soccer) or tennis: "I think there's a possibility of that. In our industry, we're all still exploring what applications are the right fit for additive, and then there's probably types of additive manufacturing that we haven't even seen commercialised yet. So I certainly think it's a possibility, it's just a matter of seeing how the technology develops."

Dr. Lippa also spoke about the possibility of the ball being used in the NBA: "Eventually we would love to see the Airless Prototype ball used competitively in some capacity. However, we have no current plans to change the NBA game ball."

Wilson Sporting Goods Co

As explained by Dr. Lippa, achieving the right design was crucial. Wilson brought in General Lattice, a Chicago based, computational design and digital manufacturing company, for the design aspect of the project.

Nick Florek, Co-Founder and CEO at General Lattice told TCT what his company brought to the table: “What we do as a company is help develop digital materials and help companies integrate those digital materials into their products. In this instance, Wilson came to us with an idea for a design of an airless basketball, and we helped them execute that design through our computational tools."

According to General Lattice, achieving the concept that Wilson put forward would have been difficult to do with traditional software tools. The company provided a solution with the ability to write custom tools and custom scripts that made the creation of a complex lattice much easier, as General Lattice Co-Founder and Chief Innovation Officer, Marek Moffett explained.

“All our clients are experts in whatever they do, right, we’re not experts in basketballs or anything like that, but when you start to do something that’s extremely complex, no matter what it is, you’re going to need newer tools or different tools or better tools. That’s where we fit in. So whatever people’s most difficult problems are, we can supply some muscle for that to get where they need to be.”

Moffet shared that the Wilson basketball was one of the first commercial projects the team at General Lattice had worked on. The tools created were based on specked out parameters from Wilson. The CINO said that this allows for users to quickly explore ‘endless’ amounts of iterations and concepts that would previously have taken an ‘exuberant’ amount of time.

From the perspective of General Lattice, the project was a great success and, according to Florek, there is the possibility of the company continuing to work with Wilson in the future.

“The journey to General Lattice was a long journey," Dr. Lippa said of choosing to collaborate with General Lattice. "I had heard of them shortly after they were starting to make themselves known from going to AMUG, Rapid + TCT and the like, but there were so many companies to sift through. It was hard to know, who had what expertise, and it took time having those conversations and working with different folks.

“There were certain geometries that we were just having trouble making in some of the traditional software, and somewhere along the way, we got introduced to General Lattice. I think several people tried to introduce us at the same time because it was just converging into that solution. As soon as we started working with them, it started to make a lot more sense because what we drew or what we handed them, half-finished CAD and then explained, ‘we want it to look like this, but we want it to wrap around this way,’ they were able to implement that faster and easier than any of our other partners had.”

Wilson Sporting Goods Co

After the design of the ball was finalised, EOS 3D printed the prototype ball on an EOS P 396 system.

David Krzeminski, PhD., Senior Consultant with Additive Minds at EOS told TCT: “Wilson introduced EOS to this project several years ago, we loved the idea and knew it would be challenging project requiring new ideas. Our team understood that replacing the multiple components of a basketball cover with one SLS material, as well as ‘taking the air out’, would require a unique solution.

"From the first printed samples, we saw that SLS 3D printing technology was capable of meeting initial requirements. Then, partnering with our partner organisations, General Lattice and Advanced Laser Materials, the iterative process of adjusting design files, testing materials, and engineering printing parameters led us to success, a basketball prototype that looks and performs like a traditional ball.”

Krzeminski told TCT how EOS was able to pull some ideas from former projects. Previously, EOS had developed Digital Foam projects and products for applications in footwear and protective headgear, which Krzeminski said had allowed the company to anticipate hurdles and streamline solutions. However, the task of developing a sphere that performed equivalently in all directions was a whole new challenge.

Krzemenski explained: “The part itself, is the first of its kind, the definition of unique. Time after time during this project we had to create and engineer unique solutions for each unique challenge. The shape of a basketball is seemingly simple, yet measured against the strict requirements of professional basketball specifications and professional athletes feedback means there is nowhere to hide any manufacturing mistakes. Suddenly, simple becomes slightly complex.”

According to EOS, Digital Foam is a ‘unique’ approach to flexible applications. It was recently used for another sporting application with Bauer Hockey for the development of the Bauer REAKT helmet.

When asked about his overall thoughts on the finished project, after the dunk, Krzemenski told TCT: “So many thoughts keep going through my head these past few weeks since the Dunk Contest. I know everyone involved put in many hours to make this happen, and the passion and attention to detail across our teams is undeniable. I still get a bit speechless when I hold one of the balls, it simply becomes real and is quite amazing.

"When I look at it, I remain fascinated at the see-through lattice, but I still always review the individual cells and see all the intention placed into each lattice strut. The ball appears so elegant, and then when you bounce it you get to experience its power and resilience. In the end, the Wilson team did an incredible job creating a product and an experience that we all will never forget.”

Wilson Sporting Goods Co

For the post-processing stage of the project, EOS introduced Wilson to DyeMansion, a specialist in finishing technologies for additively manufactured parts. In a press release from General Lattice, Lester Hitch, Application Consultant at DyeMansion North America said: “With basketball being a ‘low equipment’ sport, changing the most critical element, the basketball, is no small venture. It was the focus of our team in North America to fine tune the vapour smoothing treatment creating a consistent finish that matched Wilson team’s expectations based on experience making basketballs.”

Dr. Lippa elaborated on the collaboration: “They did such a great job of handling the large influx of samples leading up to the dunk contest when we were really honing things in. They were kind of brought into the project a little bit later, so I was really impressed with how they handled that work.”

First exposed to 3D printing in 2015 during an internship at Deakin University in Australia, Dr. Lippa recalls how, at that time, people were printing solid parts, and the use of lattices was not as common.

“To see the technology advance from that stage, where we were all really impressed with it, but kind of didn’t know what to do with it to now where it’s being implemented more thoughtfully, is really great," Dr. Lippa said. "Of course, in between those two stages is experiences like prototyping and thinking ‘okay we’re just going to look at this in making a model’ but moving towards manufacturability. I really see the next frontier is right on the horizon.”

Looking to the future and further applications, potentially commercial, at Wilson, Dr. Lippa said: "We obviously don't want this to be a one and done, that would be kind of a wasted effort for all parties, we really want this to perpetuate into some kind of product or release. Because we haven't gained those insights that we normally would do, but people are aware of this project, we're like, why not put something out there?

"We're hoping to put out a release at some point. I'd say in the next 12 months would be great, but we'll see how it goes, with a short run so that more people can get their hands on the ball and tell us what they like and hate about it."

Debuting at the NBA All-Star Weekend brought millions of eyes to the product and, vicariously, to the possibilities of 3D printing. On what this could mean for attracting young people to the additive manufacturing industry, Florek said: "I think to show something as cool as this is hopefully inspiring to people, helping people from such as young age to be curious about computational design we think is such a benefit to the industry, because you have the technology but now you need people to know how to use the technology, and the more people who can do that, the more applications come to life."

The Wilson 3D printed airless prototype basketball will be going on a mini tour in the coming weeks and months. Its first stop was at the Additive Manufacturing Users Group Conference in March, but Dr. Lippa said there are also plans to showcase the ball in a more extended way at RAPID + TCT in May.

Want to discuss? Join the conversation on the TCT Additive Manufacturing Network.

Get your FREE print subscription to TCT Magazine.

Exhibit at the UK's definitive and most influential 3D printing and additive manufacturing event, TCT 3Sixty.

by Oliver Johnson

28 March 2023

18:00