- Preston Tobery
PuppyCow Farm Goat Rescue - Prosthesis devices for Alice
Hello friends! Let me tell you about the unbelievable week that I had with Alice the goat and her momma, Shawna Riche of PuppyCow Farm Goat Rescue. If you haven't heard of this amazing rescue, please pause and watch The Dodo's video about Betsy the PuppyCow and learn all about Shawna and her love of special needs animals. The short time that I spent out in Iowa was both challenging and life changing. I compare it to my trip last year to Nicaragua. Like that trip, I was hesitant to take the challenge at first, but I am so happy that I agreed. I learned so much while there and it gave me the confidence to grow into helping special needs livestock.
Alice, the troublemaker - photo @puppycow
Leading up to the visit
Around 8 months ago, Shawna reached out to me to ask if I would ever consider creating prosthetic devices for a special needs goat. I was very hesitant in the early stages. I'm a cat guy, and I know dogs as well... but a goat? Yeah, it took me a little while to warm up to the idea. Shawna was very understanding and considerate, but she is, let's just say compassionate about helping all animals and didn't give up on me or Alice. We chatted periodically for a few months and basically started a friendship, all the while I know that she was warming me up to idea of helping Alice. After about 2 months of research, consulting with veterinarian friends, more research, and the occasional picture of Alice stuck in a cart I finally agreed. Alice unfortunately lost her legs from frostbite as a baby. But, it didn't hurt her fantastic spirit. This girl is a laser focused fighter with a heart of gold. And, she's pretty damn cute too!
Beautiful Alice - Photo @puppycow
Using my knowledge of creating a lower arm prosthetic for a friend of mine a few years ago, I decided to first task Shawna with creating molds of Alice's rear legs. This was the same method that I used for my friend Charles. For human's this is not a big deal, but working with a squirmy goat, I am sure that Shawna had a fun time with that. After receiving instructions from me, Shawna was able to create exact replicas of Alice's legs that she then sent my way. I received them a few days later, and holding those little casts in my hands warmed my heart. I knew at that very moment that I made the right decision. Shortly after that the unfortunate world event came, which was Covid-19. I had to pause my work with Alice, close my business, and completely focus on creating 3D printed face shields for our front line heroes. (Look for that blog post in the future, it was yet another life changing moment for me.) A few weeks later I was able to reopen my business, so I reached back out to Shawna and let her know that I would be continuing the process. The next step of the plan was to take those casts and 3D scan them to make digital copies that I would then be able to build the devices around in CAD (computer aided design software). This was the exact method that I used for Charles' prosthetic arm. Like human's that require prosthesis, Alice needed a comfortable fit, and for her back to be completely straight to make sure that she is able to get the most out of the devices. Turns out that a 3D scanner wasn't the best method for this, so I resorted to taking about 300 pictures from all angles of the casts and splice them together in a program called Autodesk ReCap. It was a lot of work, but totally worth it. Now that the casts were in digital form, I was able to create Alice's sockets using Matterhackers Pro series flexible filament. The material is fantastic and provides just a little "squish" for Alice's comfort.
Measuring and Test fitting the casts to flexible 3D printed sockets
Designing the Main Devices
During the very little downtime that I had during face shield production, in the late evenings I did watch many videos of goats walking, running, and climbing. I wanted to be as prepared as possible before I started on the initial design. I also found a few other really wonderful makers that are helping larger animals for design inspiration. I primarily use a CAD program called Autodesk Fusion 360. I taught myself this really involved program a few years ago and I am constantly learning new things about it that I hope to someday be able to teach others. If you didn't know this about me already helping animals and teaching are my biggest passions. I decided to focus on what I called the "rocking chair" design for the prototype knowing that it may be a while before Alice is able to run or climb. I felt that it would provide the most support while keeping it lightweight and somewhat easy to 3D print. It would also have an upper section that would hopefully provide a way to attach the devices to her and provide support right above her hock and along her thighs. The initial design work took me about 30 hours, and the test 3D print was around 7 hours. The best part was that the 3 pieces together only weighed around 300 grams including the stainless steel nuts and bolts!
Version 1 - "Rocking Chair"
Version 1 - "Rocking Chair" test 3D print
Road Trip to Iowa!
After I was finished the initial design work and 3D prints and speaking with Shawna, we decided that it would be best if I were to drive out to Iowa from Maryland for the fitting. This was my very first venture into special needs livestock and I honestly wanted to experience it all in person and have the ability to change things on the fly. This was also my first experience with animal prosthesis. I try my best to be present for most carts that I create just in case things need to be changed for a better, more customized fit for that specific animal. So, I packed up two 3D printers, lots of plastic filament, Alice's devices, some tools, and I hit the road. 14 hours later I arrived at the beautiful PuppyCow Farm Goat Rescue located near Riverside. It's been almost 30 years since I was last out this way, and I had forgotten how gorgeous it is in the mid-west. It was truly amazing to finally meet Shawna and Alice in person after all of this time.
Day 1 - Morning
Fitting day! WooHoo! The first thing that Shawna and I did was to test fit the flexible 3D printed sockets onto Alice's legs. They were a tight fit at first using baby socks. We thought we may need to reprint them with slightly larger leg holes. Fortunately, it turned out that Shawna is pretty handy with tools. She worked hard using a Dremel rotory tool with a round rubber attachment to both smooth the insides while providing an extra millimeter or two for Alice's leg hair which wasn't present on the leg casts. We also discovered that we didn't need to use the baby socks after all because the fit was pretty good.
Test fitting the flexible 3D printed sockets
After the sockets were ready, we worked on figuring out the best way to attach the devices to Alice's legs. In the initial design, I created a place for a Velcro strap to be used, and Shawna had a bunch of vet wrap ready to assist with the connection. The fit was almost perfect. We were definitely into Alice matching her devices as seen by the cute bows on Alice's horns!
After Alice was ready, it was time. To be completely honest my heart was pounding. I was so very excited to see what would happen! And then, that moment came...
Alice stands!! As you can see in the video, her rear legs went up right in the air, she had no idea what the heck these things attached to her were and why things felt different. But when she put them down, ate a little grass, and what I think realized that they were there for assistance, she slowly started walking around and headed directly towards her goat friends in a pen a short distance away. Her tail was waging and she seemed to understand that the devices were her "legs". In case you were wondering by now, yeah, I did cry a little. This is a big deal for such a wonderful goat who has never walked this way before, and a big deal for me to step out of my comfort zone. We decided that a few minutes was enough and that we wanted to do a small redesign to remove the "rocking chair" part as you might have heard us talking about in the video. So, back to work on version 2 the Ballet Slippers!
1st trial - 15 minutes and Alice was tired
Day 1 - Evening
After a late lunch, I got to work on version 2 which we called the "ballet slippers". This version would remove the rounded bottom to hopefully mimic Alice's hooves a little more. The redesign took me about 2 hours, then I got the file ready to print overnight on my old school Makerbot Replicator 2, which I named Phoebe some time ago. I usually name all of my 3D printers. It makes it easier for me to create software profiles for them and remember exactly which printer that I am setting things up for. And, for all of my maker friends reading this, I was using ProtoPasta's HTPLA filament because... sparkles, who doesn't like sparkles? They also create a fantastic product that is easy to use and produces amazing prints. That evening, we also talked about a slight redesign of the flexible sockets. But, more on that later.
Phoebe printing Version 2 - The Ballet Slippers.
Yet another beautiful day in Iowa! Today, Shawna and I placed Alice's ballet slippers on to see if this version would be better for her. We also noticed that we should definitely pursue the idea of an alternative method for the sockets. Maybe 3D printing a new flexible version wasn't the way to go. The sockets were difficult to slip onto Alice's legs, probably because she grew a bit since I received the casts months ago. The fitting went well, and after about an hour we though maybe we should add some grip to the bottoms of the design.
V1 & V2 together, and wrapping Alice up for her walk
The previous evening, Shawna and I created new sockets using Alice's casts and a product called Sugru moldable glue. It comes in 2 parts that you knead together and you have around 15 minutes to work with before it starts hardening. The end result is flexible and really easy to shape with a hobby knife or Dremel. I will definitely utilize this stuff in the future. Unfortunately, we didn't come up with a catchy name for version 3. And though she was able to walk in them, it seemed that they didn't quite have enough mass on the bottom to give Alice the proper support. They seemed to make Alice bend her hocks (knees) in an odd way. But damn, she looked so cute!
Sugru molded sockets, Version 3 with bottom grips, and gorgeous Alice!
While watching Alice walk around for about an hour, Shawna and I discussed version 4. Maybe a hybrid of the Rocking Chair and Ballet Slippers? Could we redesign the flexible 3D printed sockets for an easier placement? The blue Sugru sockets worked, but they seemed to slip quite a bit. Shawna did come up with a brilliant idea to put 4 channels into the original socket design to allow them to open up like a flower while placing them on Alice. So, back to work for me and another few hours of design and 3D printing.
Today was a good day! Version 4, a hybrid of the previous versions. In the pictures below you will see a smaller rocking chair and the 4 channels in the flexible, 3D printed socket. The red socket opened up like a flower and made for a very easy way to connect to Alice. She was able to walk around for quite some time, as well as lay down on her own! Being in a wheeled cart, Alice has never really been able to lay down periodically through the day on her own. Shawna does take her out for rest a lot, but it does take time and now she has comfort in knowing that Alice can do just a little more independently. We were extremely happy with this version and are looking forward to Alice strengthening her muscles to be able to someday run and play!
Version 4 - Hybrid
Version 4 Hybrid with "flower" sockets
"Flower" vs Static Flexible Socket
Day 5 - A Realization
Working alongside Shawna for those several days had been amazing. She is an extremely hard working and caring advocate for special needs (and all) animals that I have a lot of respect for. We discussed a lot of things throughout the week and we almost immediately realized that we would make a really great team if we were to partner up really soon. We are still working out the details of an Adaptive Tech / PuppyCow partnership, but me having a smooth way of expanding into special needs livestock sounds both challenging and exciting! Having a person that knows these animals so well would help me with the design work even more than I could imagine. The proposed idea would be for PuppyCow to acquire a 3D printer and she would be able to print the designs that I create out in Iowa and possibly deliver and fit them to animals in need.
We are super excited to start this adventure and look forward to helping so many animals! We thank you for reading this post and we will definitely keep everyone updated as we go.
If you would like to provide a tax deductible donation to PuppyCow, you can find all of the information at https://linktr.ee/puppycow.
Here's a few amazing pictures of the many animals that I was able to spend time with during the week!