Investigation of Manufacturing Techniques and Prototyping of the Smartcities Citycar Frame

A study was performed to analyze different methods of manufacturing a full scale car frame for the Smart Cities Citycar, a folding electric vehicle being designed at the MIT Media Lab, as well as a half-scale prototype for testing driving and folding systems. Through looking at two case studies for similarly sized automobiles as well as analyzing the compatibility of metal casting, stamping, composite layup, and tube welding, it was resolved that the most effective method of manufacturing the full scale Citycar frame, in the future, will be through tube hydroforming because of the optimization of strength, stiffness, and cost. It is recommended that the planned half-scale prototype be produced using composite layup techniques as the facilities for heavy machinery operations are not readily available. There will be a foam mold created on which carbon fiber will be applied to create a strong, stiff, and light model that is useful for the future of the group in its testing and prototyping. Thesis Supervisor: David Wallace Title: Professor of Mechanical Engineering