1 Rationale for Human-Powered Vehicle Design and Use
This book is about the design of vehicles with wheels that are powered by human muscles alone. These can provide affordable, sustainable, and healthy transportation to people around the globe. The term Human-Powered Vehicle, or HPV, is sometimes used to denote a sub-class of vehicles including only high-performance bicycles or tricycles equipped with aerodynamic fairings. More generally, the term refer to any semi-recumbent bicycle. But the term should properly refer to any means of carriage, conveyance, or transport that is powered solely by human muscles. Manufacturers of bicycles, canoes, kayaks, and scooters do not market their products as HPVs, but surely all of these qualify for the name. Hybrid human-powered vehicles such as mopeds and electric bikes use human power in addition to other sources. While these vehicles are outside our definition of HPVs, they are certainly similar, in both technology and philosophy.