Supporting Online Material

Biomechanical Energy Harvesting: Generating Electricity During Walking with Minimal User Effort
J. M. Donelan, Q. Li, V. Naing, J. A. Hoffer, D. J. Weber, A. D. Kuo

Supporting Online Material

This supplement contains:
Materials and Methods
Figs. S1 to S3
Table S1

This file is in Adobe Acrobat PDF format.

Other Supporting Online Material for this manuscript includes the following:
(available at
Movies S1 to S4

Movie S1
Generative Braking - In this mode, we programmed the harvester to engage only during the end of the swing phase, producing electrical power while simultaneously assisting the knee flexor muscles in decelerating the knee. The mask and mouthpiece measure the metabolic cost. We use the cabling and computer to engage and disengage power generation and for quantifying the amount of generated power.

Movie S2
Continuous Generation - In this mode, the device harvests energy whenever the knee is extending irrespective of whether or not the knee is accelerating or decelerating.

Movie S3
Disengaged - In this mode, we decoupled the gear train and generator from knee motion. It served as a control condition to estimate the metabolic cost of carrying the harvester mass, independent of the cost of generating electricity.

Movie S4
Normal Walking - Comparing this movie to the other movies illustrates that walking with and without wearing the device is qualitatively similar.

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