Design of an internal three-speed hub for a manual wheelchair

Abstract EN

The low efficiency of manual wheelchairs makes them difficult or impossible for some individuals to use effectively.

The purpose of this study was to develop a prototype three-speed wheelchair hub that could potentially increase wheelchair propulsion efficiency and increase mobility for people who have difficulty effectively propelling a classical manual wheelchair.

The design criteria were based upon the development of a proof-of-concept prototype.

Given the design criteria it was decided to pursue a planetary type gear system.

We were able to identity a commercially available bicycle hub that met most of our design criteria.

Therefore, we decided to modify a three-speed bicycle hub for wheelchair use.

The total cost of the parts and supplies for this project were about $160.

Approximately, 40 hours of machine shop time were required.

Upon using the hubs, we discovered an unexpected problem that needs to be overcome in future design work.

The pushrim moved about 15> with each stroke prior to engaging.

This problem occurred in both the forward and reverse directions.

Studies should continue to search for viable alternatives to pushrim wheelchair propulsion.