College - Author 1

College of Engineering

Department - Author 1

Mechanical Engineering Department

Degree Name - Author 1

BS in Mechanical Engineering



Primary Advisor

Sarah Harding


Nathan’s Mobility Device is a California Polytechnic State University senior project composed of a team of four mechanical engineering students that designed, built and implemented a specialized seat on an existing mobility device. Nathan, the sole beneficiary of this project, is an 11-year-old boy afflicted with a condition known as Spinal Muscular Atrophy (SMA) which causes him extreme muscular weakness. In this report, the team discussed the problem at hand, provides preliminary research and product benchmarking (evaluation and comparison to specific criteria), and described the ideation, prototyping, testing, and iteration plan. In addition, the team explored the final design in detail while confirming that each component was within the specified budget, meets Nathan’s required criteria, and functions safely and appropriately. This final design review discusses the final design choices incorporated into the mobility device and the manufacturing and testing procedures done to achieve the final product. Manufacturing and testing were divided into mechanical and electrical subgroups and have their respective risk assessments and critical tests outlined in the sections six and seven.

In the first two months of receiving this project, the team was undecided between modifying an existing power scooter that either focused on comfort or building a mobility device from scratch that focuses on aesthetics at the expense of reliability. In analyzing the hierarchy of Nathan’s needs and collaborating with his mother, Amy, team members decided to forfeit the latter idea and settle on a mobility base to build upon. This report spans the period before, during, and after this choice was made.

The report also identifies the constraints that will be considered for the design to ensure that the project is within the scope of the team’s expertise. Some of these constraints include: budgeting, working within the scope of work, and modifying the mobility base without damaging existing components.