Engineering Students 3D Print a Mobility Device for Duck the Three-Legged Dog

Duck, a young rescue dog found abandoned along a roadside in Oklahoma, was born with only three legs. She gets around well enough on her own, but staff at Free to Live Animal Sanctuary near Guthrie noticed she tires on longer walks. So they gave a team of University of Oklahoma engineering freshmen a real design challenge: build something that helps.

The students were part of OU's Engineering Summer Bridge program, a pre-college experience for incoming engineering students who live on campus, take a math class, and solve a hands-on design project before their first semester begins. Over four weeks in summer 2026, teams of four students designed and prototyped mobility devices for Duck using CAD software, electronic circuits, and 3D-printed components. The most promising designs will continue to be refined after the program ends, with the goal of delivering a functional device Duck can use at the sanctuary on a regular basis.

What the Students Actually Built

The teams did not print a single off-the-shelf wheelchair design and call it done. Each group started by researching canine anatomy, specifically the gait mechanics of a front-limb-deficient dog, and assessed Duck's movement patterns at the sanctuary before sketching concepts. The design process included multiple rounds of prototyping, physical testing, and iteration. Several teams incorporated small electronic sensors into their designs, which suggests at least some of the prototypes included responsive elements rather than purely passive braces.

One consistent through-line across the student teams: they treated Duck as a user with specific biomechanical requirements rather than a generic case study. That framing is unusual in early engineering education, where most first projects involve abstract problems or standardized test cases.

Why the Program Structure Matters

The 2026 Summer Bridge program drew a record 160 applicants for 40 spots, and one in three participants are first-generation college students. Corporate partners including ExxonMobil and ConocoPhillips funded the program and provided guest speakers, site visits, and project mentorship. Brandon Abbott, the program director, said the goal was to give students a broader definition of engineering than the one they arrived with: technical skill is the foundation, but engineering is a service discipline, and the problems worth solving belong to people.

The Duck project is a clean example of that framing. The engineering is real: load paths, material selection, ergonomic contact surfaces, and actuation design all apply. The context makes it stick in a way that a textbook problem does not.

3D Printing's Role

Custom prosthetics and mobility aids are one of the better-documented use cases for desktop 3D printing. Commercial dog wheelchairs exist, but they are sized by weight class and fitted with adjustable straps. A 3D-printed device built around an individual dog's measurements can produce a closer fit, and the iteration cycle is fast enough that four teams can each go through multiple design generations within a four-week window. That rapid iteration is the specific advantage 3D printing brings to this kind of project.

The RIT team's multi-material prosthetic finger research, published in the same week, is the academic-scale version of the same idea: patient-specific geometry, custom materials, and rapid iteration. The OU project is smaller in scope but it runs on the same logic, and it reaches a real user sooner.

What Happens Next

Free to Live Animal Sanctuary will evaluate the prototype designs and work with the most promising teams to refine the device for Duck's everyday use. The Summer Bridge program has already opened applications for 2027, and if this year's project is any indication, the next cohort will be arriving with high expectations for what their engineering education is supposed to feel like.