Research Papers

Lower Limb-Driven Energy Harvester: Modeling, Design, and Performance Evaluation

[+] Author and Article Information
Jean-Paul Martin, Michael Shepertycky, Qingguo Li

Bio-Mechatronics and Robotics Laboratory,
Department of Mechanical and
Materials Engineering,
Queen's University,
Kingston, ON K7L 3N6, Canada

Yan-Fei Liu

Power Group,
Department of Electrical and
Computer Engineering,
Queen's University,
Kingston, ON K7L 3N6, Canada

1J.-P. Martin and M. Shepertycky contributed equally to this work.

Manuscript received June 4, 2015; final manuscript received February 5, 2016; published online August 24, 2016. Assoc. Editor: Carl Nelson.

J. Med. Devices 10(4), 041005 (Aug 24, 2016) (9 pages) Paper No: MED-15-1207; doi: 10.1115/1.4033014 History: Received June 04, 2015; Revised February 05, 2016

Biomechanical energy harvesters (BMEHs) have shown that useable amounts of electricity can be generated from daily movement. Where access to an electrical power grid is limited, BMEHs are a viable alternative to accommodate energy requirements for portable electronics. In this paper, we present the detailed design and dynamic model of a lower limb-driven energy harvester that predicts the device output and the load on the user. Comparing with existing harvester models, the novelty of the proposed model is that it incorporates the energy required for useful electricity generation, stored inertial energy, and both mechanical and electrical losses within the device. The model is validated with the lower limb-driven energy harvester in 12 unique configurations with a combination of four different motor and three different electrical resistance combinations (3.5 Ω, 7 Ω, and 12 Ω). A case study shows that the device can generate between 3.6 and 15.5 W with an efficiency between 39.8% and 72.5%. The model was able to predict the harvester output peak voltage within 5.6 ± 3.2% error and the peak force it exerts on the user within 9.9 ± 3.4% error over a range of parameter values. The model will help to identify configurations to achieve a high harvester efficiency and provide a better understanding of how parameters affect both the timing and magnitude of the load felt by the user.

Copyright © 2016 by ASME
Your Session has timed out. Please sign back in to continue.


Romero, E. , Warrington, R. , and Neuman, M. , 2009, “ Energy Scavenging Sources for Biomedical Sensors,” Physiol. Meas., 30(9), pp. R35–62. [CrossRef] [PubMed]
Riemer, R. , and Shapiro, A. , 2011, “ Biomechanical Energy Harvesting From Human Motion: Theory, State of the Art, Design Guidelines, and Future Directions,” J. Neuroeng. Rehabil., 8(1), pp. 22–35. [CrossRef] [PubMed]
Schertzer, E. , and Riemer, R. , 2015, “ Harvesting Biomechanical Energy or Carrying Batteries? An Evaluation Method Based on a Comparison of Metabolic Power,” J. Neuroeng. Rehabil., 12(1), pp. 30–42. [CrossRef] [PubMed]
Niu, P. , Chapman, P. , Riemer, R. , and Zhang, X. , 2004, “ Evaluation of Motions and Actuation Methods for Biomechanical Energy Harvesting,” IEEE 35th Annual Power Electronics Specialists Conference (PESC 04), Aachen, Germany, June 20–25, Vol. 3, pp. 2100–2106.
Starner, T. , and Paradiso, J. A. , 2004, “ Human-Generated Power for Mobile Electronics,” Low-Power Electronics Design, C. Piguet, ed., CRC Press, Boca Raton, FL, Chap. 45.
Li, Q. , Naing, V. , Hoffer, J. A. , Weber, D. J. , Kuo, A. D. , and Donelan, J. M. , 2008, “ Biomechanical Energy Harvesting: Apparatus and Method,” IEEE International Conference on Robotics and Automation (ICRA), Pasadena, CA, May 19–23, pp. 3672–3677.
Xie, L. , and Du, R. , 2012, “ Harvest Human Kinetic Energy to Power Portable Electronics,” J. Mech. Sci. Technol., 26(7), pp. 2005–2008. [CrossRef]
Rome, L. C. , Flynn, L. , Goldman, E. M. , and Yoo, T. D. , 2005, “ Generating Electricity While Walking With Loads,” Science, 309(5741), pp. 1725–1728. [CrossRef] [PubMed]
Niu, P. , Chapman, P. , DiBerardino, L. , and Hsiao-Wecksler, E. , 2008, “ Design and Optimization of a Biomechanical Energy Harvesting Device,” Power Electronics Specialists Conference (PESC 2008), Rhodes, Greece, June 15–19, pp. 4062–4069.
Von Buren, T. , Mitcheson, P. D. , Green, T. C. , Yeatman, E. M. , Holmes, A. S. , and Troster, G. , 2006, “ Optimization of Inertial Micropower Generators for Human Walking Motion,” IEEE Sens. J., 6(1), pp. 28–38. [CrossRef]
Romero, E. , Warrington, R. O. , and Neuman, M. R. , 2009, “ Body Motion for Powering Biomedical Devices,” Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC 2009), Minneapolis, MN, Sept. 3–6, pp. 2752–2755.
Granstrom, J. , Feenstra, J. , Sodano, H. A. , and Farinholt, K. , 2007, “ Energy Harvesting From a Backpack Instrumented With Piezoelectric Shoulder Straps,” Smart Mater. Struct., 16(5), pp. 1810–1821. [CrossRef]
Xie, L. , and Cai, M. , 2015, “ Development of a Suspended Backpack for Harvesting Biomechanical Energy,” ASME J. Mech. Des., 137(5), p. 054503. [CrossRef]
Hayashida, J. Y. , 2000, “ Unobtrusive Integration of Magnetic Generator Systems Into Common Footwear,” Ph.D. thesis, Media Laboratory, Massachusetts Institute of Technology, Cambridge, MA.
Kornbluh, R. D. , Pelrine, R. , Pei, Q. , Heydt, R. , Stanford, S. , Oh, S. , and Eckerle, J. , 2002, “ Electroelastomers: Applications of Dielectric Elastomer Transducers for Actuation, Generation, and Smart Structures,” Proc. SPIE, 4698, pp. 254–270.
Gilbert, J. M. , and Balouchi, F. , 2014, “ Design and Optimisation of a Footfall Energy Harvesting System,” J. Intell. Mater. Syst. Struct., 25(14), pp. 1746–1756. [CrossRef]
Xie, L. , and Cai, M. , 2015, “ An In-Shoe Harvester With Motion Magnification for Scavenging Energy From Human Foot Strike,” IEEE/ASME Mechatronics, 20(6), pp. 3264–3268. [CrossRef]
Dai, D. , and Liu, J. , 2014, “ Hip-Mounted Electromagnetic Generator to Harvest Energy From Human Motion,” Front. Energy, 8(2), pp. 173–181. [CrossRef]
Li, Q. , Naing, V. , and Donelan, J. M. , 2009, “ Development of a Biomechanical Energy Harvester,” J. Neuroeng. Rehabil., 6(1), pp. 22–34. [CrossRef] [PubMed]
Shepertycky, M. , and Li, Q. , 2015, “ Generating Electricity During Walking With a Lower Limb-Driven Energy Harvester: Targeting a Minimum User Effort,” PLoS One, 10(6), p. e0127635. [CrossRef] [PubMed]
Rubinshtein, Z. , Riemer, R. , and Ben-Yaakov, S. , 2012, “ Modeling and Analysis of Brushless Generator Based Biomechanical Energy Harvesting System,” IEEE Energy Conversion Congress and Exposition (ECCE), Raleigh, NC, Sept. 15–20, pp. 2784–2789.
Pozzi, M. , Aung, M. S. , Zhu, M. , Jones, R. K. , and Goulermas, J. Y. , 2012, “ The Pizzicato Knee-Joint Energy Harvester: Characterization With Biomechanical Data and the Effect of Backpack Load,” Smart Mater. Struct., 21(7), p. 075023. [CrossRef]
Donelan, J. , Li, Q. , Naing, V. , Hoffer, J. , Weber, D. , and Kuo, A. , 2008, “ Biomechanical Energy Harvesting: Generating Electricity During Walking With Minimal User Effort,” Science, 319(5864), pp. 807–810. [CrossRef] [PubMed]
Dell, 2016, “ Inspiron 1525/1526 Product Information,” Dell, Round Rock, TX, http://support.dell.com/support/edocs/systems/ins1525/en/index.htm
Nokia, 2008, “  Nokia 6301 Data Sheet,” Nokia, Espoo, Finland.
Ossur, 2009, “  Proprio Foot Technical Manual,” Ossur, Reykjavík, Iceland, http://assets.ossur.com/lisalib/getfile.aspx?itemid=12360
Shepertycky, M. , 2013, “ The Development and Performance Evaluation of an Energy Harvesting Backpack,” M.S. thesis, Queen's University, Kingston, ON, Canada.
Maxon Motors, 2016, “  Maxon DC and EC Motors,” Maxon Motors, Brünigstrasse, Switzerland, accessed June 5, 2014, www.maxonmotor.com
SKF, 2014, “ The SKF Model for Calculating the Frictional Moment,” SKF, Göteborg, Sweden.
SKF, 2010, “Needle Roller Bearings,” SKF, Göteborg, Sweden.
Shigley, J. E. , 2011, Shigley's Mechanical Engineering Design, Tata McGraw-Hill Education, New York.
Lee, S. J. , and Hidler, J. , 2008, “ Biomechanics of Overground vs. Treadmill Walking in Healthy Individuals,” J. Appl. Physiol., 104(3), pp. 747–755. [CrossRef] [PubMed]
Riley, P. O. , Paolini, G. , Della Croce, U. , Paylo, K. W. , and Kerrigan, D. C. , 2007, “ A Kinematic and Kinetic Comparison of Overground and Treadmill Walking in Healthy Subjects,” Gait Posture, 26(1), pp. 17–24. [CrossRef] [PubMed]


Grahic Jump Location
Fig. 1

(a) Schematic of a gait cycle indicating time of cable retraction and cable extension of the right leg. (b) Both left and right cable length over a complete gait cycle. (c) Cable velocity of both left and right cable and combined positive velocity of both cables. Modified from Ref. [20].

Grahic Jump Location
Fig. 2

The lower limb-driven energy harvesting device. (a) Schematic showing how the harvester is worn by the user. Modified from Ref. [20]. (b) Components of the retraction mechanism: a constant force spring exerting a force on the input pulley, while its other end freely coils about an idler pulley. Cable path: the cable passes over two sets of idler pulleys, redirecting its path to be coiled about the input pulley. Gear train: the input pulley transfers motion to an input shaft. Motion is then transferred to a drive gear via a one-way roller clutch (shown in removed section). The motion is amplified through a single stage gear ratio to the driven gear. The driven gear is mounted on the generator shaft (not shown in the figure).

Grahic Jump Location
Fig. 3

Schematic showing internal components engaged in each state. (a) Coupled state. The input shaft is engaged with the remainder of the system. Engaged components include both left and right drive gears, driven gear, generator, input shaft, input pulley, and the retraction spring. (b) Decoupled state. The input shaft is not mechanically engaged with the remainder of the gear train due to the overrun of the roller clutch. Engaged components include input shaft, input pulley, and the retraction spring.

Grahic Jump Location
Fig. 4

(a) Gear train assembly shows which components of the drive train are rotating at the same speed in each state. (b) Input and generator shaft angular velocity as a function of time. The generator shaft angular velocity is reduced by the overall gear ratio for direct comparison. Vertical dashed line indicates the time (tc) that decoupling begins, where the generator shaft overruns the input shaft. t0 indicates initiation of swing and t1 indicates the beginning of swing of the opposite limb.

Grahic Jump Location
Fig. 7

(a) The angular velocity and angular acceleration of the M2(R3.5) condition. (b) and (c) show the electrical, inertial, and mechanical force contributions to total force, for conditions M2(R3.5) and M4(R12), respectively. Data are segmented to show a single step (50–100% of gait cycle), with vertical hatched lines indicating swing, beginning of cable extension, and the end of swing for the right leg.

Grahic Jump Location
Fig. 6

(a) The measured input angular velocity amplified by the overall gear ratio, N, and the model's predicted angular velocity of the generator, showing angular velocity after decoupling. Overlaid is the measured input angular acceleration. (b) Measured and predicted generated voltage for the M1(R3.5) condition. (c) Measured and predicted force exerted on the user for the M1(R3.5) condition. The coinciding phase of gait is shown as reference. Decoupling is indicated as a vertical hatched line.

Grahic Jump Location
Fig. 5

Mechanical and electrical power produced in each test condition. Overall device efficiency (ηtotal) is the ratio of electrical power produced to the mechanical power required.




Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In