Design of a Portable Assisted Mobility Device — A sustainable urban transport

A Portable Assisted Mobility Device (PAMD) is being investigated for future transportation by the Partners for the Advancement of Collaborative Engineering Education (PACE) Program. PACE is a consortium of 37 universities from several countries sponsored by the General Motors (GM) Company and a number of its key suppliers. The PACE program strives to educate and inspire students to design future transportation systems with appropriate economic and social constraints all the while fostering global collaboration among participants. In this article we describe the work performed by students of Tuskegee University as part of this design project. Literature search on current PAMD and similar devices has been completed. The literature search included the Honda UX-3, YikeBike, Volkswagen Bike, and Toyota iReal. After the literature search, customer surveys and possible risk analysis were completed to help develop design specifications. The results conclude that our design needed to be user friendly, foldable, lightweight, and economical. Three different possible device concepts were developed using the NX7.5 software. A comparison of each concept to the existing devices was conducted and iterated to select the final design parameters. From these specifications, a detailed computer-aided design was developed. Engineering analysis on the strength of the structure was made using the Nastran software. The maximum speed and traveling distance of the PAMD were calculated. The results showed that a carbon fiber composite frame with a safety factor of 5 would be strong enough for the average sized customer. The maximum stress was observed to be 380,000 psi at the main folding joint of the frame. The highest speed of the PAMD was determined to be 11.2 m/s and the device was capable of traveling a distance of 18 km.