In this study, an effective noncontact and nonattached technique that is based on electrostatic induction current generated during walking motion is proposed for the detection and assessment of human physical activity. In addition, a theoretical model is proposed for the electrostatic induction current generated owing to variation in the electric potential of the human body. The proposed electrostatic induction current model is compared with the theoretical model, and the proposed model is shown to effectively explain the behavior of the electrostatic induction current waveform. The normal walking motions of daily living are recorded with a portable sensor located in a regular house. The obtained results show that detailed information of physical activity such as a gait cycle can be estimated using our proposed technique. Additionally, the walking signal was measured when the subject walked with the ankle and knee fastened to a splint with bandages to simulate a limp. Therefore, the proposed technique, which is based on the detection of signal generated during walking, can be successfully employed to assess human physical activity.
Cite this paper
Kurita, K. (2014) Human Physical Activity Measurement Method Based on Electrostatic Induction. Journal of Sensor Technology
, 139-147. doi: 10.4236/jst.2014.43013
 Davis, M.G. and Fox, K.R. (2007) Physical Activity Patterns Assessed by Accelerometry in Older People. European Journal of Applied Physiology, 100, 581-589. http://dx.doi.org/10.1007/s00421-006-0320-8
 Rikli, R.E. (2000) Reliability, Validity, and Methodological Issues in Assessing Physical Activity in Older Adults. Research Quarterly for Exercise Sport, 71, S89-S96.
 Plasqui, G. and Westerterp, K.R. (2007) Physical Activity Assessment with Accelerometers: An Evaluation against Doubly Labeled Water. Obesity, 15, 2371-2379. http://dx.doi.org/10.1038/oby.2007.281
 Pate, R.R., et al. (1995) Physical Activity and Public Health. A Recommendation from the Centers for Disease Control and Prevention and the American College of Sports Medicine. Journal of the American Medical Association, 273, 402-407. http://dx.doi.org/10.1001/jama.1995.03520290054029
 Ballor, D.L. and Keesev, R.E. (1991) A Meta-Analysis of the Factors Affecting Exercise-Induced Changes in Body Mass, Fat Mass, and Fat-Free Mass in Males and Females. International Journal of Obesity, 5, 717-726.
 Fogelholm, M. (2000) Effects of Walking Training on Weight Management after a Very Low Energy Diet in Premenopausal Obese Women: A Randomized Controlled Trial. Archives of Internal Medicine, 160, 2177-2184.
 Dunn, A.L. (1999) Comparison of Lifestyle and Structured Interventions to Increase Physical Activity and Cardiorespiratory Fitness: A Randomized Trial. Journal of the American Medical Association, 281, 327-334.
 Morris, J.R.W. (1973) Accelerometry—A Technique for the Measurement of Human Body Movements. Journal of Biomechanics, 6, 729-739. http://dx.doi.org/10.1016/0021-9290(73)90029-8
 Williamson, R. and Andrews, B.J. (2001) Detecting Absolute Human Knee Angle and Angular Velocity Using Accelerometers and Rate Gyroscopes. Medical Biological Engineering Computing, 39, 1-9.
 Mansfield, A. and Lyons, G.M. (2003) The Use of Accelerometry to Detect Heel Contact Events for Use as a Sensor in FES Assisted Walking. Medical Engineering Physics, 25, 879-885. http://dx.doi.org/10.1016/S1350-4533(03)00116-4
 Amoruso, V., et al. (2000) An Improved Model of Man for ESD Application. Journal of Electrostatics, 49, 225-244.
 Ohsawa, A. (2001) Electrostatic Characterization of Antistatic Floors Using an Equivalent Circuit Model. Journal of Electrostatics, 51-52, 625-631. http://dx.doi.org/10.1016/S0304-3886(01)00031-6
 Ficker, T. (2006) Electrification of Human Body by Walking. Journal of Electrostatics, 64, 10-16.
 Kurita, K. (2009) New Estimation Method for the Electric Potential of the Human Body under Perfect Noncontact Conditions. IEEJ Transactions on Electrical and Electronic Engineering, 4, 309-311.