Design and manufacturing proposal for a stair-climbing wheelchair without an external power source

• Main Authors: Rivera, Alfredo (Alfredo M.), Studley, Timothy
• Other Authors: Daniel Frey.
• Format: Others
• Language: English
• Published: Massachusetts Institute of Technology 2008
• Subjects: Mechanical Engineering.
• Online Access: http://hdl.handle.net/1721.1/40945

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007. === Includes bibliographical references (leaf 26). === With over two million wheelchair users in the United States, many buildings have struggled to provide accessible elevators and ramps for the disabled. The only other option for the disabled to ascend stairs is to purchase a high-tech battery-operated wheelchair with elaborate sensors and gyroscopes, which can cost around $25,000. As a result, there is a high demand for a cheap and efficient way to climb stairs with a practical wheelchair. With the safety of the user as a main concern, it is the goal of this report to provide a light-weight, inexpensive stair-climbing wheelchair. In order to significantly reduce cost of production, the wheelchair will not have any outside power source. The user's strength is the only means of energy for climbing. Our specific design relies on three critical modules: wheels with retractable spokes, a lock-in ratchet on the axel, and a seat-tilting mechanism. By focusing on integrating light-weight materials into the design, the force required to operate the wheelchair should be very manageable. The next stages of manufacturing were determined and explicitly outlined. Using SolidWorks and previously developed components, a complete manufacturing proposal has been formulated. The production calls for two additional wheels with retractable spokes, two locking mechanisms of the main axel, and a tilt-in-space feature using gas springs. The final product should provide the disabled with a safe, reliable, and inexpensive wheelchair capable of ascending nearly any staircase. === by Alfredo Rivera [and] Timothy Studley. === S.B.