Injured sea turtle swims again with 3D printed harness

Connecticut’s Mystic Aquarium is home to thousands of aquatic animals, from penguins to beluga whales. Since 2008, Mystic has also been home to Charlotte, a green sea turtle who was rescued by the aquarium following a boat injury that left him unable to swim properly. Now, after 16 years of struggling to swim, Charlotte is regaining his abilities thanks to a custom harness realized through a partnership between New England 3D printing solutions company Adia, New Balance Athletics and Formlabs.

After being hit by a boat nearly two decades ago, Charlotte the sea turtle has been dealing with a peculiar condition known as “bubble butt” (or Positive Bouancy Syndrome). More specifically, the accident resulted in the paralysis of his two rear flippers and caused air to become trapped in the back of his shell, which has made his rear end more buoyant than normal and causes him to swim at a strange angle with his head down.

For the past five years, the Mystic Aquarium team has been working on a solution to help the sea turtle swim normally once more. In this journey, the aquarium team found a partner in Adia, a local 3D printing solutions provider, which in turn brought on specialists from Formlabs and the computational design team from New Balance Athletics to help.

Starting with a 3D scan of Charlotte the sea turtle, the team designed a series of prototype harnesses that would help mitigate the effects of “bubble butt”. Very recently, Charlotte was fitted with the latest version of the harness, which was 3D printed using the Formlabs Fuse SLS machine and Nylon 11 CF, a carbon-fiber reinforced powder that offered a good strength-to-weight ratio for the application at hand.

The harness itself integrates a special weight system that Charlotte’s handlers can adjust based on the position of the air bubble in the turtle’s shell. The weight system effectively balances out the large sea turtle as he swims as well as helps with the partial paralysis of his rear flippers. According to the team, the harness functions as a rehabilitation device, “helping the turtle redevelop lost muscle and mobility in the hind flippers and tail.” Since testing out the new 3D printed harness, Charlotte’s handler Claire has reported positive results.

With the extensive work done to develop the harness and its success so far, Adia is hoping to help more sea turtles who suffer from “bubble butt”. In fact, Adia and the New Balance team who worked on the harness have put out a call for collaborators who specialize in 3D printing, computational design and materials science in the hopes that they can develop more harnesses to help rescued turtles with the syndrome. As the partners say: “A successful effort could extend the assistance to a much broader audience of green sea turtles at both aquariums and rescue facilities, and show the potential of 3D capture, automated workflows and printing for the benefit of animal rehabilitation efforts.”