Design of an Ergonomic Wheelchair Drive System for Improved Shoulder Biomechanics1

Design of a Folding-Frame Ergonomic Wheelchair

“…The primary concern with reducing the spline drive used in the first design [5] to the desired size for this prototype was the capibiltiy of the smaller diameter spline to transmit the torque loading, from the hand rim to the drive wheel, during normal usage. Previous studies [6] report a peak resultant hand rim force of 225 N while propelling a chair up a 5° incline.…”

“…This feature allowed chain tension to be increased or decreased easily, even after the whole assembly was put together. This feature increased usability as compared to the previous design which used a turnbuckle to adjust chain tension [5]. The turnbuckle method did not allow for easy adjustability, as the user would need to reach completely under the chair to make any necessary changes.…”

“…To reduce shoulder pain while keeping the wheelchair stable, an ergonomic wheelchair using a chain drive system to remotely connect the hand rims to the drive wheels was designed in 2016 [5]. However, there were several improvements to be made on this design.…”

“…However, there were several improvements to be made on this design. The overall chair had a mass of 19.4 kg and was incorporated on a fixed frame [5]. This design had many positive features that were refined for the new design, including 1 Contact author: heinx092@umn.edu.…”