(Additively manufactured cleat positioned between shoe and pedal on Stevin Creegan’s race bike. Image Credit: NZDF)

Ten years after a helicopter crash changed air force veteran, Stevin Creeggan’s life. Now a team of New Zealand Defence Force engineers is using additive manufacturing to help change it again. 

In 2010, Stevin Creeggan’s life changed forever. He was the sole survivor of a helicopter crash at Pukerua Bay, north of the New Zealand capital, Wellington. Stevin was left with multiple injuries including self-fused vertebrae in his neck and lower back, and severe damage to his right leg which has been reconstructed with plates, screws, and rods to hold his femur and lower femur together. It is also now shorter than his left leg by 2.5 centimeters. 

After the accident Stevin found it difficult to find a way to maintain his fitness so turned to cycling, eventually putting his name forward to compete in the Invictus Games, founded in 2014 by Prince Harry, for current and former service personnel who have been wounded or injured. He is due to compete next year in archery, wheelchair basketball and cycling events. 

(Stevin Creegan in the saddle during Invictus Games training.  Image credit: NZDF)

With one leg shorter than the other Stevin first made himself a spacer, a thin or often tapered material used to fill small gaps or spaces between objects, to fill the gap between his right foot and his bike pedal. “I first used bog; the material that panel beaters use when they fill a dent in a car. It’s strong but very heavy. I spoke to my Invictus sports team manager, David Pilgrim, who took it to the NZDF engineering design team without me knowing. When I found that out you could have knocked me over with a feather, I was so surprised!”

Ewan Conaghan and Martin Campbell were the New Zealand Defence Force mechanical engineers at the receiving end of David’s request to make something lighter and more resilient to aid Stevin on his Invictus Games journey. An avid cyclist himself, Martin jumped at the opportunity. “I have a long history with pushbikes and when this job came in, I jumped at the chance, it was just made for me.” 

But, as Ewan explained, it was a little out of the ordinary for a design engineering team more used to designing military vehicle parts through to tentage and bespoke prototypes and , “We are mechanical engineers, but people will knock on our door with all sorts of ideas. As soon as we saw David’s request, we knew immediately that 3D printing was the way to go.” 

Stevin’s bog-crafted spacer and shoe cleat, to attach to the bike pedal, weighed 250 grams, “that is ridiculously heavy and so one of our primary tasks was to work out how to significantly reduce its weight, whilst maintaining its strength and resilience to the outdoors,” said Martin. The team designed and printed a couple of carbon fibre prototypes, working with Stevin to perfect the piece, “with GE’s additive technology, using titanium we were able to reduce the weight to 50 grams which was just great for Stev and the design is specific to his shoe,” he continued.  

 
(L-R: Martin Campbell and Ewan Conaghan, NZDF engineers adjusting the PLA 3D printed prototype to ensure good form and fit. Image credit: NZDF)

Zenith Tecnica, an Auckland-based manufacturer, printed the final piece in titanium using a GE Additive Arcam Electron Beam Melting (EBM) Q10plus machine. Zenith’s technical manager, Peter Sefont, said the design was simply beautiful, “we only had to suggest a few small tweaks to get to the final design and it allowed us to get the most out of the additive technology.” Stevin agrees, “I have had quite a few comments on how beautiful the design is and questions as to how it keeps its strength. A lot of people don’t realize there is a spacer there at first and that’s a testament to 3D printing technology and titanium.” 

Zenith Tecnica usually works on parts for the aerospace, motorsports, marine and medical sectors so this was a foray into something new, “Our GE Additive EBM machines are certified to 3D print titanium aerospace and medical parts. We make quite a few customized patient specific implants and prosthetics, as mass customisation is one of the key benefits to 3D printing, but the pedal spacer and cleat is not something we have manufactured before so it was great to be a part of it,” Peter continued. 

Whilst the 2020 Invictus Games, scheduled for May, did not go ahead due to COVID-19, they are expected to take place next year and the titanium spacer and cleat has given Stevin added confidence, “the design team found that sweet spot in the middle of being light, functional and strong. My right leg is now ergonomically correct so it is now at the point where I can stand up to pedal and I have trust in my leg and my bike to push harder than I have been able to before. I am now doing 23 kilometers in 30 minutes in the track criterium, up from 18 kilometers.” 

Beyond the rescheduled Invictus Games Stevin will continue with cycling, “since the accident, the spacer and cleat have been the biggest game changer for me for sport or anything else. I had the chance to go in and say thank you to the design team and their pride in helping to create something for me on my Invictus journey just blew me away. It was awesome.” 

(Stevin Creeggan, back row, second from left with the NDZF Invictus Games cycling team. Image credit: NDZF)

CINCINNATI, OH – Cincinnati Zoo & Botanical Garden is home to 2,000 animals, including world-famous hippo Fiona, and is committed to providing each one with excellent care.  Thanks to a novel partnership with GE Additive, known for pushing the boundaries of industrial 3D printing (often referred to additive manufacturing), some of the animals are getting meals from a fabricated feeder that encourages natural foraging behaviors.   

“Something that we often think about is how to mimic natural feeding behaviors in the animals that we care for. In the wild, animals are adapted to find, acquire, and process food – and it’s not always easy! In human care though, food is always available and of good quality and balance, and in many cases, it’s consumed quite quickly,” said David Orban, Cincinnati Zoo’s animal excellence manager.

“For example, one challenge that we often see when we offer live insects to some of our birds or small mammals is that they are captured and consumed in a matter of five to ten minutes. We’ve had the idea to create a more complex feeder that will extend foraging duration, in turn, extending animals’ physical activity and mental stimulation, leading to more naturally behaving wildlife,” added Orban.

Orban heads up a team that observes and documents how animals are spending their days and how they interact with their environments and with each other.  This data is used to better understand animals’ experiences at the Cincinnati Zoo and can be used to inform facets of animal care, including husbandry, diet, habitat design, and innovative enrichment solutions.

Engineers from GE Additive’s AddWorks consulting team in Cincinnati used data collected by the Zoo’s animal researchers and keepers to imagine how metal 3D printing technology could help give animals the opportunity to find their food as they would in the wild.

“To kick things off, the Zoo team showed us around and explained their goal to keep animals engaged and enriched. We were thrilled to be working with such an atypical customer and challenge that would allow us to demonstrate that, with additive technology, the sky really is the limit”, said Shannon Jagodinski, lead engineer at GE Additive in Cincinnati.

One of the challenges in this pro bono project was learning how to communicate with each other – engineer to zoologist and vice versa. Another was helping the Cincinnati Zoo team understand the possibilities that 3D printing creates.

“Additive technology allows a design to incorporate any shape, angle, structure or texture that is needed, with metal or plastic. The first thing that we considered was safety for the animals, keepers, and visitors and then the Zoo’s request that the animal enrichment device look natural within the environment,” added Jagodinski.

After their initial meetings, the engineers at GE Additive and the enrichment team and keepers at the Zoo began exchanging their design thoughts for a new feeder.  The Zoo collected as many ideas as possible from the animal care staff for new enrichment experiences for the animals.

The GE engineers assessed these concepts for design feasibility, bearing in mind the specific considerations that go into designing an additive part - everything from part orientation on the additive machine build plate to powder removal. They presented two ideas to the Zoo team, who then selected the design they thought would provide the biggest benefit to the broadest group of animals. The first part was printed, using recycled Titanium powder, in February this year. 

The final product is a device that disconnects the keepers from feeding the animals, disbursing food into habitats at random times, which is more like an experience that the animals would have in the wild. The exterior of the device replicates a tree trunk with a bark-like texture, and the inside of the feeder has a central enclosure to house crickets, which is connected to varying length tubes that exit the device at different points along the exterior.

Depending on which tube the cricket selects, it takes a different amount of time to leave the device, which therefore provides crickets to the animals at varying times.

“After this feeder concept was selected, my initial questions were ‘how big is a cricket and what size tube do they need to crawl through?’ We got some feedback from the Zoo’s insect team and tried three different tube sizes. We printed prototype tubes with three different diameters and tested them in a cricket enclosure at the zoo to see which size worked best,” said Jagodinski.

Despite Zoos all over the world being temporarily closed due to the COVID-19 pandemic, the GE Additive team in Cincinnati was able to deliver one finished device before lockdown. Zookeepers have been able to use this time to experiment with, and test, the efficacy of the feeder first with birds, then with smaller insectivorous mammals such as meerkats.

“We have seen that foraging time and the animals’ investigation and interaction last for up to a few hours in our tests compared to a few minutes, which is really exciting for us because that means we can utilize it multiple times a day and in different habitats. We have really seen that a lot of animals have been interested in it and continue to stay interested in it, which is exactly what we wanted,” said David Orban.

GE Additive will be delivering several more of the feeding devices to the Cincinnati Zoo, including one for education around animal enrichment and 3D printing capability. This demo piece will remove a portion of the bark textured exterior to expose the complex and intricate internal passageways made possible with metal 3D printing to teach school groups and other visitors.

“If there’s one thing I continue to learn with additive is that every customer has their own unique challenges. It is amazing to see the positive impact that this unique partnership has had for the animals,” said Dave Chapin, leader of the AddWorks consulting team at GE Additive.

As for Jagodinski, she’s looking forward to the day the famous Cincinnati landmark re-opens its gates, post Coronavirus, “I’m excited to be able to go to the zoo with my family and friends and to point into a habitat and say hey I worked on that, that’s a titanium additive part, and that was created using 3D printing technology.”

CAD models of metal 3D Printed cricket feeder for Cincinnati Zoo

Inside the metal 3D printed cricket feeder. Device installed at the Discovery Rainforest at Cincinnati Zoo

Animals at Cincinnati Zoo engaging with the metal 3D printed cricket feeders.

Callaway Golf Company the leading manufacturer of high-performance golf equipment has signed a consultancy agreement with GE Additive’s AddWorks team to help it harness the potential of additive manufacturing. Shown at formnext, the first project resulting from the agreement is a redesigned Odyssey R-Ball putter.