Aer E 423 Project Katarzyna Szemplinska 12/13/2008

 Michelin’s product development ◦ Tire and wheel combined into one – Tweel TM  Tweel TM objectives ◦ Replace conventional tires ◦ Reduce maintenance costs ◦ Improve performance

 Apply Tweel TM concept to bicycle wheels  Analyze Tweel TM feasibility and performance

 Different spoke designs  Multiple composite materials combinations  Assumptions: ◦ Load is split equally between the two wheels ◦ Load is applied vertically  Initial configuration: ◦ Outer Rim Diameter = 24 in. ◦ Inner Rim Diameter = 4 in. ◦ Load per Wheel = 90 lbs.

 Spokes: Carbon fiber prepreg  4-ply layup  Cured in an autoclave  Warping  Outer and Inner Rim: Fiberglass with Epoxy  4-ply hand layup  Cured at room temperature  Spoke Reinforcement: Fiberglass with Epoxy  2-ply hand layup  Cured at room temperature  Mold Structure: Styrofoam  Hand cut

 Compression testing ◦ MTS testing machine  Preliminary testing: Spoke

 Tweel TM Compression Testing

 Spoke bending was successful  Rim/spoke interface strength was not sufficient  Outer rim flexibility needs to be eliminated ◦ Load transfer to spokes  Concept is feasible  Performance evaluation with improved design