Engineering in Tandem: Mines Students Design a Dog-Powered Cart System for Navy Veteran MaryRita Emmerick

When Navy veteran MaryRita Emmerick began training her new service dog, M.E., she knew he would eventually help her with daily tasks that are becoming harder to manage alone: carrying groceries, transporting household items, and hauling the sewing materials she uses to volunteer with Quilts of Valor. What she didn’t expect was that a team of engineering students from the Colorado School of Mines would step in to design a fully customized system that would help the two of them work as one.

This year, a group of seniors in the Human-Centered Design Studio chose MaryRita’s project for their capstone assignment through Project S.E.R.V.E. They even gave themselves the perfect team name: D.A.W.G.S. — the Dog Assistive Work Gear System. Their challenge is deceptively complex: create a lightweight, foldable wagon and attachment harness that M.E. can safely pull, while ensuring the system is easy for MaryRita to load, store, and use in the flow of everyday life.

But the heart of the project is even more nuanced. They aren’t designing for one user. They’re designing for two — a veteran and her trained service companion — each with their own comfort, safety, and mobility needs.

From the outset, the students immersed themselves in MaryRita’s world. They visited the spaces she navigates most often, including her local library, where tight corners, ramps, and elevators can pose real challenges. They studied clearances, slopes, and turning radii, learning quickly that a dog-powered cart must be more stable and intuitive than the typical consumer wagon. They also spent time with M.E., assessing how weight transfers through a dog’s body and how to distribute load without causing strain or restricting movement.

This early research shaped the core design direction: a tactical-style vest for M.E. with reinforced connection points, paired with parallel aluminum sidebars that transfer pulling force safely from the dog’s shoulders to the redesigned cart. The team is crafting a system that stays under 20 pounds, can carry 50 pounds of groceries or sewing supplies, and folds down small enough to slide into the trunk of MaryRita’s car without hassle.

The cart itself is being reimagined from an existing model — a blend of familiarity and new functionality. The students are adapting it for improved stability on inclines, smoother indoor maneuvering, and easier cleaning. Every detail, from the handle height to the wheelbase, is being reconsidered through the lens of someone relying on the system daily.

What’s remarkable in watching this project unfold is how deeply the students have internalized the dual-user nature of the design. They’re not only thinking about tensile forces, load limitations, and ADA considerations; they’re thinking about how MaryRita will carry the cart to her vehicle, how M.E. will feel when walking downhill, and how the pair will communicate through the harness. They’re designing for safety, but also for dignity, independence, and confidence.

For MaryRita, this system represents much more than a cart. It’s a way to stay active, maintain her routines, and continue contributing to her community. For the students, it’s a chance to build something that will matter immediately and tangibly in someone’s life — the kind of engineering students remember long after graduation.

This is the essence of Project S.E.R.V.E.: practical, compassionate innovation that restores freedom and resilience for the people who have served all of us.