Biomechanical energy harvesting: Apparatus and method

A biomechanical energy harvester is presented that generates electricity during human walking. The key feature of this device is that the power generation adds only a minimal extra effort to the user. The knee-mounted devices accomplish this by selectively engaging power generation at the end of the swing phase when knee flexor muscles act to brake knee motion. Analogous to regenerative braking in hybrid cars, the device assists deceleration of each leg within each stride while generating electrical power. We developed a control system to engage/disengage power generation based on the measured knee kinematics during a gait cycle. Experimental results show that generative braking generated 4.8 plusmn 0.8 W of electrical power with a minimal increase in metabolic cost.

[1]  R M Enoka.  Load- and skill-related changes in segmental contributions to a weightlifting movement. , 1988, Medicine and science in sports and exercise.

[2]  Joseph A. Paradiso,et al.  Human Generated Power for Mobile Electronics , 2004 .

[3]  P Webb,et al.  The work of walking: a calorimetric study. , 1988, Medicine and science in sports and exercise.

[4]  Roger M. Enoka.  Load- and skill-related changes in segmental contributions to a weightlifting movement. , 1988 .

[5]  A. Hof,et al.  Speed dependence of averaged EMG profiles in walking. , 2002, Gait & posture.

[6]  Arthur D Kuo.  Harvesting Energy by Improving the Economy of Human Walking , 2005, Science.

[7]  N. Demirdöven,et al.  Hybrid Cars Now, Fuel Cell Cars Later , 2004, Science.

[8]  Taeseung D. Yoo,et al.  Generating Electricity While Walking with Loads , 2005, Science.

[9]  J. Donelan,et al.  Mechanical work for step-to-step transitions is a major determinant of the metabolic cost of human walking. , 2002, The Journal of experimental biology.

[10]  Thad Starner,et al.  Human-Powered Wearable Computing , 1996, IBM Syst. J..

[11]  Rodger Kram,et al.  Simultaneous positive and negative external mechanical work in human walking. , 2002, Journal of biomechanics.

[12]  J A Hoffer,et al.  Biomechanical Energy Harvesting: Generating Electricity During Walking with Minimal User Effort , 2008, Science.

[13]  L. Pugh.  The influence of wind resistance in running and walking and the mechanical efficiency of work against horizontal or vertical forces , 1971, The Journal of physiology.

[14]  R. Kram,et al.  Mechanical and metabolic determinants of the preferred step width in human walking , 2001, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[15]  Joseph A. Paradiso,et al.  Energy scavenging for mobile and wireless electronics , 2005, IEEE Pervasive Computing.