Stakeholder-Driven Design Evolution of the Leveraged Freedom Chair Developing World Wheelchair
Name
Stakeholder-driven.pdf
Size
2.59 MB
Format
Adobe PDF
Checksum (MD5)
5adf6367d2967fd7e1ca0910800a5316
Author(s)
Mukherjee, Sudipto
Winter, Amos G.
Bollini, Mario A
Judge, Benjamin M
Scolnik, Natasha
O'Hanley, Harrison F
Dorsch, Daniel S.
Frey, Daniel
Date Issued
November 2012
Journal
ASME 2012 International Mechanical Engineering Congress and Exposition, Volume 5: Education and Globalization; General Topics
Publisher
American Society of Mechanical Engineers (ASME)
Citation
Winter, Amos G.; Bollini, Mario A.; Judge, Benjamin M.; Scolnik, Natasha K.; O’Hanley, Harrison F.; Dorsch, Daniel S.; Mukherjee, Sudipto and Frey, Daniel D.“Stakeholder-Driven Design Evolution of the Leveraged Freedom Chair Developing World Wheelchair.” ASME 2012 International Mechanical Engineering Congress and Exposition, Volume 5: Education and Globalization; General Topics, American Society of Mechanical Engineers, November 2012.
Version
Final published version
Abstract
The Leveraged Freedom Chair (LFC) is a low-cost, all-terrain, variable mechanical advantage, lever-propelled wheelchair designed for use in developing countries. The user effectively changes gear by shifting his hands along the levers; grasping near the ends increases torque delivered to the drive-train, while grasping near the pivots enables a larger angular displacement with every stroke, which increases angular velocity in the drivetrain and makes the chair go faster. This paper chronicles the design evolution of the LFC through three user trials in East Africa, Guatemala, and India. Feedback from test subjects was used to refine the chair between trials, resulting in a device 9.1 kg (20 lbs) lighter, 8.9 cm (3.5 in) narrower, and with a center of gravity 12.7 cm (5 in) lower than the first iteration. Survey data substantiated increases in performance after successive iterations. Quantitative biomechanical performance data were also measured during the Guatemala and India trials, which showed the LFC to be 76 percent faster and 41 percent more efficient during a common daily commute and able to produce 51 percent higher peak propulsion force compared to conventional, pushrim-propelled wheelchairs.
MIT Department
Massachusetts Institute of Technology. Department of Mechanical Engineering
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1115/IMECE2012-88881
