Foldable cycle for hikers

As a part of our group project, we were given a task to design a foldable cycle for hikers under 4 kg, with which the hikers can climb up the hill with the cycle in their backpack, and while returning they can unfold the cycle and come down by cycling. It was a cool and fun project, the most difficult task was to keep it foldable and most important, under 4 kg.  We used the CATIA student version at our university TH Ingolstadt. we started with the concepts and some rough drawing, but CATIA made is very easy to shape up out ideas into realities.  At the end, the professors were really satisfied with our work and they appreciated our efforts.