A wonderful and simple student design for a wheelchair appropriate to the far-from-paved conditions of the developing world. It's a smart, simple design, and is made using standard bicycle parts, which should allow for easy repairs and creative modifications in the communities where they're used. In East Africa a few years back, the main wheelchair type I saw on the street were full tricycles with a longer wheelbase and an elevated bicycle crank turned by hand. The levers look to be a vast improvement, allowing the chair to be useful both indoors and out.