At the Cincinnati Zoo and Botanical Garden, keeping animals fed and physically cared for is only part of the zookeepers’ responsibility. Engaging those animals and providing mental stimulation as well is an ongoing challenge. One method of enrichment is interactive feeders—devices that encourage an animal to engage with its food in a way that imitates how that food would be acquired in the wild. 

The Cool Parts Show traveled to the Cincinnati Zoo to see one such enrichment device, a metal 3D printed feeder made by GE Additive (another Cincinnati-based organization) designed to provide a more natural hunting and eating experience for insectovores. The feeder resembles a tree stump but contains an internal chamber and winding passageways that allow live crickets to make their way out of the device and into an animal’s enclosure at their own speed. Using this device,  birds, foxes and the meerkats featured in this episode can be fed and mentally challenged with minimal human involvement. | Season 3 of The Cool Parts Show brought to you by Carpenter Additive

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Resources and links

• The Cincinnati Zoo and Botanical Garden
• GE Additive
• Initial announcement of the feeder project
• More on electron beam melting (EBM)

Considerations When 3D Printing for a Zoo

• Animal safety. To keep the animals safe, the team considered how the animal’s body parts and movements would interact with various geometries. Could a tooth get stuck, for instance?
• Human safety. What are all the ways humans will need to interact with a part? Will a human pick it up? Carry it? Clean it?
• Aesthetics. Does the part need to visually fit into a certain environment or look a certain way to invite or deter animals (or guests)?

Transcript

Pete Zelinski 

Additive manufacturing applications improve the lives of people. But what about animals?

Stephanie Hendrixson 

We'll look at a case where 3D printing is improving the lives of animals here at the Cincinnati Zoo in this episode of The Cool Parts Show.

Season 3 of The Cool Parts Show is brought to you by Carpenter Additive. The company's Athens, Alabama Emerging Technology Center is an end to end additive manufacturing production facility, with everything from materials development through post processing under one roof, ready to help you with your next metal 3D printing job. Check them out at CarpenterAdditive.com. Now back to the show.

Pete Zelinski 

I'm Pete.

Stephanie Hendrixson 

I'm Stephanie.

Pete Zelinski 

We're with AdditiveManufacturing.media and this is The Cool Parts Show, our show all about cool, amazing, interesting 3D-printed parts.

Stephanie Hendrixson 

This is our first on-site episode of The Cool Parts Show we are here at the Cincinnati Zoo and Botanical Garden and we're going to be talking about a 3D printing application here that's used for the animals with the help of some special guests.

Pete Zelinski 

We're going to talk about meerkats, because who wouldn't want to talk about meerkats? But we're also going to talk about something bigger, which is additive manufacturing has potential to solve problems, including problems you didn't even imagine could have a connection to 3D printing.

Stephanie Hendrixson 

So while you're enjoying the antics of these little guys behind us, we're going to be talking about a 3D printed enrichment device that was made right here in Cincinnati.

Pete Zelinski 

Yeah, this is a great hometown story for us. We are based in Cincinnati. This involves GE Additive, a company based in Cincinnati, and the Cincinnati Zoo and Botanical Gardens is a real source of local pride for us. But this is also a story about building bridges between different disciplines. And as we'll explore this one was a pretty big bridge.

Stephanie Hendrixson 

Yeah. So before we get too far into this, the part that we're going to be talking about is actually behind us in the meerkat enclosure. So regular viewers of the show are used to seeing us sitting behind a table handling the part, today the meerkats are gonna be doing the handling. And what we're looking at is this thing that kind of looks like an upright tree stump in here.

This is a 3D printed enrichment device. It's three pieces of titanium assembled together, and it looks solid, but actually like there's this internal chamber where a zookeeper can add crickets. And there are all these different channels on the inside, where the live crickets can kind of make their way out slowly into the enclosure, where they then are eaten by the animals.

Pete Zelinski 

Slowly, slowly is the key to the enrichment, the crickets coming out at their own natural pace as they would find their way out. So the challenge of feeding animals in a zoo is it's possible to feed them too easily and too quickly. These mere cats could get fed physically and wouldn't be stimulated mentally. And the feeder is all about that making eating a little challenging for the meerkats. So before we go farther: meerkats. What can you tell us about these animals?

Stephanie Hendrixson 

So meerkats are from Africa. They are part of the mongoose family. And they're burrowing creatures, so you'll see them digging around behind us. And fun fact, the group or the “mob” that we have here in Cincinnati actually came from Disney's Animal Kingdom. And they're all related.

Pete Zelinski 

What do they eat?

Stephanie Hendrixson 

They are omnivores, but I believe that one of their favorite foods is bugs.

Pete Zelinski 

And so that gets to the story that we want to tell, how these animals eat, how to feed the meerkats naturally. Somebody who thinks a lot about that, how to replicate the natural experience of animals is Cincinnati Zoo's animal excellence manager, David Orban. Let's hear from him.

David Orban 

So I would describe this as kind of a slow cricket feeder, almost. Really, we have a lot of animals here at the zoo that we care for that consume insects as part of their diet. And so what we wanted to do is have a way to slowly disperse live crickets into the animals' environment, and therefore extending the foraging behavior that an animal might be doing. So this device, it has a central vessel in it that crickets can be placed into and then from that central vessel, there is a network of basically maze like tubes that lead to the exterior of the device. So crickets can then move their way from the center of the device to the exterior of it, kind of at their leisure and when they choose. So this allows crickets to be slowly dispersed into the environment, and for there to be some randomization in terms of location and time.

So we've now tested the device with a few different species, including meerkats, sandcats and Fennec foxes, as well as multiple different species of birds, including blue crowned thrushes and white crown shama thrushes, and we've noticed amongst all of those different animals, different investigative behaviors, foraging behaviors. We're happy to see that our animals were spending a lot of time searching for, and digging around and listening for crickets, and then consuming them when they did see them.

Stephanie Hendrixson 

Okay, so David talked about what is going on the inside of this feeder. And I actually talked to Shannon Jagodinski, who's an AddWorks engineer at GE Additive. She worked on this and here's how she described the design.

Shannon Jagodinski 

The exterior of this device has a tree bark-like structure printed into the outside so that it looks natural and fits into the environment. The top and bottom lids even have rings from a tree printed into them to make it look pretty natural, which is pretty neat. But the inside is way more complex than you would think just by looking at this replicated tree trunk. So we actually used internal fuel nozzle, winding passageway-type thought process to create all these tubes that wind in throughout the tree trunk. And the tubes are different lengths because the zoo had asked us to create a sort of delayed timing feeder. So depending on which tube a cricket will select, it'll take the cricket a different amount of time to walk through a shorter tube versus a longer tube. And then the tubes are even big enough that the crickets can turn around if they want and crawl back into the device. And they can stay in the device as long as they want. Eventually they'll come out and search for food.

Pete Zelinski 

So man with GE, it always comes back to the fuel nozzle doesn't it?

Stephanie Hendrixson 

It totally does. Yeah.

Pete Zelinski 

But this is not an aircraft part. It nevertheless, it's made out of titanium. Is there any sense where this is a little over engineered?

Stephanie Hendrixson 

You know, okay, that's what I thought too at first. But there's actually a couple of good reasons that this is made out of titanium and some of them are the same reasons you would make aerospace parts out of titanium. It's lightweight, it's easy for the keepers to handle; it's strong, it's durable, it's going to hold up to a lot of different animals using it in different ways. But also kind of the bigger reason is that titanium is a pretty safe material. So we use it for medical implants, we use it for surgical instruments. It's safe for humans to be in contact with and it's likewise safe for animals to be interacting with like this.

Pete Zelinski 

So isn't that funny? Because the animal enrichment team here at the zoo, they're used to making things by hand right? Making things out of wood or paper maché or PVC pipe. I bet they never imagined they would have a 3D printed titanium enrichment component. And it sort of gets at the gulf between these two disciplines. And it was a pretty wide gulf that was that was bridged by this collaboration. First, okay, we're talking about additive, we've got to cover the the technology right? What was the additive process used to make this?

Stephanie Hendrixson 

So GE Additive used electron beam melting or EBM, specifically an Arcam Q20 Plus. So you might remember, GE acquired Arcam a couple years ago. And this is, it's a powder bed technology, it's really similar to laser sintering, which we've talked about before. The main difference is that instead of a laser as your power source, you have an electron beam and that whole bed of powder is preheated. So you have to kind of break your parts out of this cake of powder instead of just lifting them out of the loose powder. So that technology allowed GE to build this device out of titanium so it's really strong and durable. But also allowed them to incorporate those really interesting internal features that kind of show off what additive can do.

Pete Zelinski 

Yeah, so turning to additive manufacturing gave the zoo access to all this capability, all this design freedom. And then from that point, this sort of turned into the kind of story we see with additive right, trying to solve a new problem with it. The problem in this case, how to get crickets to naturally exit the device the way crickets want to do. A problem never before confronted, never before addressed by additive manufacturing. And the team had to get together to work that out and there was prototyping, there was iteration, there was exploring ideas. David Orban spoke about that.

David Orban 

Originally when we started designing, I think there was really the idea to have that central chamber be a lot smaller, the tunnels inside were a lot longer and had a lot more different angles. So one thing that we did is we started to test some of those different features of the device before actually building the whole unit itself. So working with actually one of our insect team here at the zoo,we brought some different pieces that were kind of test prints to that building and we tested some of those basically different sizes and textures of tunnels. We wanted to see, you know, what crickets would use and what they would feel most comfortable with to either turn around or maybe to bypass one another or could they even navigate up a steep tunnel itself. So really working through that together, we made some adjustments to the diameter of the tubes to the size of the internal vessel.

Stephanie Hendrixson 

Wow. So that's funny, like the first beta users for this feeder were actually the food. So okay, in addition to the cricket experience, GE had to consider a couple of other things in building this feeder. And so here's what Shannon had to say about that, kind of starting from maybe the predator’s perspective.

Shannon Jagodinski 

In addition to animal safety, we had to consider all of their body parts, which sounds kind of weird. But we had to think about nails, claws, beaks, teeth, things that could get stuck in certain geometries that we could create with additive. We had to make sure that we are avoiding any type of geometry that could lead to an animal injury. And then in terms of safety for the humans interacting with the device, we had to keep the device within a maintainable weight to pick up and carry in and out of the enclosure. And then also had to make sure that the keepers had a way to keep the device clean. So we had to think about that when we were designing it as well.

One of the other requirements that the zoo wanted us to use in this project was to make something that looked natural in the animals enclosure. They wanted something that wouldn't stick out like a sore thumb for people that were coming to the zoo. Something to look sort of like trees or foliage that an animal would see out in the wild. And then the last set of restrictions and requirements that we had, were just in terms of the technology side. We had to make sure that whatever we came up with had to fit inside of one of our additive machines.

Pete Zelinski 

Alright, so I listened to them speak, I hear Shannon talk, I hear David talk. And they're describing the same application and the same set of problems, but from the framework of their two different perspectives. And both of them I'm hearing them sort of alluded to part of the challenge of this, and really, part of the fun of this was these two different disciplines and these two different organizations kind of understanding each other and understanding how to communicate with each other about this application, about solving this problem. Like so this is an additive manufacturing story. This is meerkat story, but like really, this is a people story, ultimately.

Stephanie Hendrixson 

Yeah. So you know, there are these two organizations, they are both in Cincinnati, very close geographically, experts in their fields. And the challenge here is not so much the design or the manufacturing of this device, it's how do we talk to each other? How do we express what it is that the problem we need to solve on the one hand, and how do we explain what it is that we can do and how additive can solve this problem on the other hand?

Shannon Jagodinski 

So the first couple times we met with them, we really just kind of explained where each side was coming from. So we would explain the benefits of additive technology, we would explain the limitations of additive technology. And the zoo team would explain to us what they needed help with, why they had certain problems. And once we gained a deep understanding of both sides of the story, we are able to mesh together and do a bunch of brainstorming sessions. And the most important part of those brainstorming sessions was having people at the zoo that would actually interact with the animals and could give us firsthand experiences of what they needed help with.

David Orban 

You know, we had a lot of fun just learning from each other and I think also challenging one another to think a little bit more creatively and outside the box. You know, I know that just even when they first came out to our Zoo to meet with our team they brought, they brought like two or three boxes of just different things that they've been able to print. From like a flexible chainmail to, you know, a metal ball within a ball, like the opportunities that can come from additive technology seem endless, at least from my perspective. So that was exciting for us. And I know when they came out when a few of those interviews came out to test the textures and the sizes of some of those 3D printed parts with crickets. I know a few of the members were not big fans of insects. So being in a room filled with insects all around you in different terrariums is a little bit nerve wracking for them. But again, they were a great sports about it and I think we learned a lot from each other through that experience.

Stephanie Hendrixson 

Pete, you know what, other than the bugs like this story really isn't that weird.

Pete Zelinski 

How so?

Stephanie Hendrixson 

So I think about previous people that we've talked to and like I think a lot of additive manufacturers have been in Shannon's shoes, where you're sitting down across the table from a new customer and you know, maybe they're just learning about 3D printing for the first time or they're not fully aware of all the things it can do and you have to kind of just talk it out. You know, what is 3D printing? What are its capabilities? How is it going to help in this situation? At the same time I think we've spoken to a lot of people kind of like David who have some sort of problem, and maybe they don't even see it as a problem, and somehow they find their way to 3D printing as the solution.

Pete Zelinski 

Yeah, so we're here at the zoo, we're at an unusual place, but really, we could be anywhere because the story of additive really has this potential for solving problems  and really just the connection has to be made. Just the organization with that problem somehow has to recognize that 3D printing holds the solution.

Let me see if I've got all this okay. All right, so we're at the Cincinnati Zoo and Botanical Gardens. 3D printing was used to make this feeding device. It has internal passageways that encourage crickets to find their way out, as crickets will ,according to cricket agendas, at cricket speeds, so that the meerkats are enriched. The device is titanium. And titanium was the material chosen for several reasons, including its safety for the animals, its ruggedness and durability for the long term It was made through electron beam melting, a powder bed fusion process, on an Arcam machine from GE Additive, and GE Additive engineers and animal personnel with the zoo worked together to explore the solution and find the right feeder design. And part of the challenge of it was these two organizations, one that's very concerned with and understands the well-being of animals, and one that is focused on engineering and 3D printing. Them talking together, coming together to find this successful feeding device that's now enriching our hosts the meerkats.

Stephanie Hendrixson 

Yeah, so I think that's it. But there's one more kind of communication aspect to this story. So Shannon told me that GE Additive is actually working on making a couple more of these feeders, and there's going to be one that has sort of this like cut-out section so you can see what's happening on the inside. And the zoo is going to use that as a demo piece for school groups and other visitors so that while people are here learning about animals, they can also be learning about 3D printing at the same time.

Pete Zelinski 

Okay, so let's make a promise when that's here at the zoo and available we'll update the audience so you all can come see it.

Stephanie Hendrixson 

Yeah, and if you ever find yourself in Cincinnati, highly recommend visiting the zoo and you know, take a look around see if you can spot some of these cool parts.

Pete Zelinski 

So that does it. Thank you for watching. Thanks for watching The Cool Parts Show. If you have a cool 3D-printed part you're working on that tells an interesting story maybe like this one, contact us. We might feature it in an episode, CoolParts@AdditiveManufacturing.Media.

Stephanie Hendrixson 

If you liked the show, subscribe. You can find all of the past episodes on YouTube or TheCoolPartsShow.com and more about industrial 3D printing at AdditiveManufacturing.media. Thanks for watching.

Thank you to our sponsor Carpenter Additive. Listen to additive manufacturing podcasts, attend webinars and learn more at CarpenterAdditive.com.