Building Adpative Bikes for Bella & Peyton (Senior Design Project)

Engineering isn't just about designing products—it’s about solving real problems for real people. One of the most rewarding projects I’ve worked on was designing and building adaptive bicycles for Bella and Peyton, two incredible girls with Cerebral Palsy. This project wasn’t just an engineering challenge; it was an opportunity to create something meaningful that would give them the freedom and joy of riding a bike.

The Challenge: Accessibility Meets Engineering

Our team of seven set out with a clear mission: build two fully functional, safe, and adaptive bicycles tailored to Bella and Peyton’s specific needs. Standard bikes weren’t an option—stability, weight, and ease of control were all critical factors. We needed to think outside the box.

We started by generating and modeling three different bike concepts in SolidWorks, eventually deciding on a tadpole tricycle configuration. With two wheels in the front and one in the back, this design provided better weight distribution and stability, making it easier for Bella and Peyton to maneuver.

Designing and Prototyping: From Concept to Reality

The project demanded a balance between precision engineering and hands-on fabrication. We adhered to top-down and parametric design principles while modeling the bikes in SolidWorks, ensuring that adjustments could be made efficiently throughout the process.

In the machine shop, we:

• Cut and welded frame components using TIG and MIG welding methods.

• Machined custom steering columns to fine-tune handling.

• Designed, 3D-modeled, and rapidly prototyped custom brake handle extensions to help Bella and Peyton grip and activate the brakes more easily.

One of the most critical engineering challenges was designing the steering system. Our team built and tested two different solutions, working through issues related to Ackermann steering and handling dynamics. At one point, we noticed the front wheels were collapsing inward during movement—a major safety concern. To fix this, I implemented positive caster, allowing the bike to naturally self-correct during turns. This eliminated the collapse issue and significantly improved handling.

Predicting and Testing Performance

To ensure safety, we developed mathematical and physical models to predict braking performance and stopping distance. By incorporating factors like mechanical advantage, user speed, weight, and friction coefficients, we could test and validate the models against real-world performance.

The final bikes were built to withstand the rigors of everyday use while remaining easy to maintain. Every design choice—from frame geometry to braking system—was made with safety and long-term usability in mind.

The Final Delivery & Seeing It in Action

After months of work, it was time for the true test: Bella and Peyton’s 5K race. Our team delivered the bikes on time, and both successfully completed the event without a single issue. Seeing them cross the finish line was an unforgettable moment—proof that engineering can have a direct and meaningful impact on people’s lives.

To top it off, our work was featured on WTHR Channel News, bringing awareness to the importance of adaptive engineering in accessibility-focused design.

Lessons Learned

This project was more than just a technical challenge. It was about working under tight deadlines, collaborating effectively as a team, and prioritizing human needs over technical constraints. It reinforced the idea that great engineering is about understanding people just as much as it is about solving problems.

Bella and Peyton’s smiles made every late night in the shop worth it. This experience reaffirmed my passion for designing solutions that merge engineering, accessibility, and real-world impact—and it’s something I strive to bring into every project I take on.