Human-powered wearable computing
by T. Starner http://www.research.ibm.com/journal/sj/353/sectione/starner.txt
Batteries add size, weight, and inconvenience to present-day mobile computers. This paper explores the possibility of harnessing the energy expended during the user's everyday actions to generate power for his or her computer, thus eliminating the impediment of batteries.
An analysis of power generation through leg motion is presented in depth, and a survey of other methods such as generation by breath or blood pressure, body heat, and finger and limb motion is also presented. Wearable computing is an effort to make computers truly part of our everyday lives by embedding them into our clothing (e.g., shoes) or by creating form factors that can be used like clothing (e.g., sunglasses) This level of access to computation will revolutionize how computers are used.
Although the computational hardware has been reduced in size to accommodate this vision, power systems are still bulky and inconvenient. Even today's laptops and PDAs (personal digital assistants) are often limited by battery capacity, output current, and the necessity of having an electrical outlet within easy access for recharging. However, if energy can be generated by the user's actions, these problems will be alleviated.