Annals of Biomedical Engineering

, Volume 44, Issue 4, pp 1246–1256 | Cite as

Laboratory Evaluation of the gForce Tracker™, a Head Impact Kinematic Measuring Device for Use in Football Helmets

  • Kody R. CampbellEmail author
  • Meagan J. Warnica
  • Iris C. Levine
  • Jeffrey S. Brooks
  • Andrew C. Laing
  • Timothy A. Burkhart
  • James P. Dickey


This study sought to compare a new head impact-monitoring device, which is not limited to specific helmet styles, against reference accelerometer measurements. Laboratory controlled impacts were delivered using a linear pneumatic impactor to a Hybrid III headform (HIII) fitted with a football helmet and the impact monitoring device (gForce Tracker-GFT) affixed to the inside of the helmet. Linear regression analyses and absolute mean percent error (MAPE) were used to compare the head impact kinematics measured by the GFT to a reference accelerometer located at the HIII’s center of mass. The coefficients of determination were strong for the peak linear acceleration, peak rotational velocity, and HIC15 across all impact testing locations (r 2 = 0.82, 0.94, and 0.70, respectively), but there were large MAPE for the peak linear acceleration and HIC15 (MAPE = 49 ± 21% and 108 ± 58%). The raw GFT was accurate at measuring the peak rotational velocity at the center of mass of the HIII (MAPE = 9%). Results from the impact testing were used to develop a correction algorithm. The coefficients of determination for all impact parameters improved using the correction algorithm for the GFT (r 2 > 0.97), and the MAPE were less than 14%. The GFT appears to be a suitable impact-monitoring device that is not limited to specific styles of football helmets, however, correction algorithms will need to be developed for each helmet style.


Concussion mTBI Head acceleration Head impact biomechanics Impact monitoring Helmet sensors 



The authors would like to thank Artaflex Inc. for providing the gForce Tracker equipment used in this study. The authors would also like to thank the efforts of Chris Withnall and Michael Wonnacott at Biokinetics & Associates, Ltd., Ottawa, Ontario, Canada, for their assistance and expertise during data collection. A NSERC Engage Grant supported this study. None of the authors have any financial interest in any of the systems used in this study.

Supplementary material

10439_2015_1391_MOESM1_ESM.pdf (1.8 mb)
Supplementary material 1 (PDF 1843 kb)


  1. 1.
    Allison M. A., Y. S. Kang, M. R. Maltese, J. H. T. Bolte, and K. B. Arbogast. Measurement of hybrid III head impact kinematics using an accelerometer and gyroscope system in ice hockey helmets. Ann. Biomed. Eng., 2014.Google Scholar
  2. 2.
    Beckwith, J. G., R. M. Greenwald, and J. J. Chu. Measuring head kinematics in football: correlation between the head impact telemetry system and hybrid III headform. Ann. Biomed. Eng. 40:237–248, 2012.CrossRefPubMedPubMedCentralGoogle Scholar
  3. 3.
    Bland, J. M., and D. G. Altman. Measuring agreement in method comparison studies. Stat. Methods Med. Res. 8:135–160, 1999.CrossRefPubMedGoogle Scholar
  4. 4.
    Camarillo, D. B., P. B. Shull, J. Mattson, R. Shultz, and D. Garza. An instrumented mouthguard for measuring linear and angular head impact kinematics in American football. Ann. Biomed. Eng. 41:1939–1949, 2013.CrossRefPubMedPubMedCentralGoogle Scholar
  5. 5.
    Cichos D., D. de Vogel, M. Otto, O. Schaar, and S. Zölsch. Crash analysis criteria description. In: Workgroup Data Processing Vehicle Safety, 2006.Google Scholar
  6. 6.
    Cobb B. R., A. MacAlister, T. J. Young, A. R. Kemper, S. Rowson, and S. M. Duma. Quantitative comparison of hybrid III and National Operating Committee on Standards for Athletic Equipment headform shape characteristics and implications on football helmet fit. Proc. Inst. Mech. Eng. Part P 1754337114548245, 2014.Google Scholar
  7. 7.
    DiMasi F. Transformation of nine-accelerometer-package (nap) data for replicating headpart kinematics and dynamic loading. Technical Report, 1995.Google Scholar
  8. 8.
    Gurdjian, E. S., H. R. Lissner, F. G. Evans, L. M. Patrick, and W. G. Hardy. Intracranial pressure and acceleration accompanying head impacts in human cadavers. Surg. Gynecol. Obstet. 113:185–190, 1961.PubMedGoogle Scholar
  9. 9.
    Guskiewicz, K. M., S. W. Marshall, J. Bailes, M. McCrea, R. C. Cantu, C. Randolph, and B. D. Jordan. Association between recurrent concussion and late-life cognitive impairment in retired professional football players. Neurosurgery 57:719–726, 2005.CrossRefPubMedGoogle Scholar
  10. 10.
    Guskiewicz, K. M., S. W. Marshall, J. Bailes, M. McCrea, H. P. Harding, Jr, A. Matthews, J. R. Mihalik, and R. C. Cantu. Recurrent concussion and risk of depression in retired professional football players. Med. Sci. Sports Exerc. 39:903–909, 2007.CrossRefPubMedGoogle Scholar
  11. 11.
    Hanlon, E., and C. Bir. Validation of a wireless head acceleration measurement system for use in soccer play. J. Appl. Biomech. 26:424–431, 2010.PubMedGoogle Scholar
  12. 12.
    Langlois, J. A., W. Rutland-Brown, and M. M. Wald. The epidemiology and impact of traumatic brain injury: a brief overview. J Head Trauma Rehabil 21:375–378, 2006.CrossRefPubMedGoogle Scholar
  13. 13.
    Manoogian, S., D. McNeely, M. Goforth, G. Brolinson, and S. Duma. Head acceleration is less than 10 percent of helmet acceleration during a football impact. Biomed. Sci. Instrum. 42:383–388, 2006.PubMedGoogle Scholar
  14. 14.
    Marar, M., N. M. McIlvain, S. K. Fields, and R. D. Comstock. Epidemiology of concussions among United States high school athletes in 20 sports. Am. J. Sports Med. 40:747–755, 2012.CrossRefPubMedGoogle Scholar
  15. 15.
    McAllister, T. W., J. C. Ford, L. A. Flashman, A. Maerlender, R. M. Greenwald, J. G. Beckwith, R. P. Bolander, T. D. Tosteson, J. H. Turco, R. Raman, and S. Jain. Effect of head impacts on diffusivity measures in a cohort of collegiate contact sport athletes. Neurology 82:63–69, 2014.CrossRefPubMedPubMedCentralGoogle Scholar
  16. 16.
    McCrea, M., T. Hammeke, G. Olsen, P. Leo, and K. Guskiewicz. Unreported concussion in high school football players: implications for prevention. Clin. J. Sport Med. 14:13–17, 2004.CrossRefPubMedGoogle Scholar
  17. 17.
    Mihalik, J. P., K. M. Guskiewicz, S. W. Marshall, J. T. Blackburn, R. C. Cantu, and R. M. Greenwald. Head impact biomechanics in youth hockey: comparisons across playing position, event types, and impact locations. Ann. Biomed. Eng. 40:141–149, 2012.CrossRefPubMedGoogle Scholar
  18. 18.
    National Committee on Standards for Athletic E. Nocsae standard linear impactor test method and equipment used in evaluating the performance characteristics of protective headgear and faceguards. Document #: 1–6, 2006.Google Scholar
  19. 19.
    Newman, J. A., M. C. Beusenberg, N. Shewchenko, C. Withnall, and E. Fournier. Verification of biomechanical methods employed in a comprehensive study of mild traumatic brain injury and the effectiveness of American football helmets. J. Biomech. 38:1469–1481, 2005.CrossRefPubMedGoogle Scholar
  20. 20.
    Pellman E. J., D. C. Viano, A. M. Tucker, I. R. Casson, and N. F. L. Committee on Mild Traumatic Brain Injury. Concussion in professional football: location and direction of helmet impacts-Part 2. Neurosurgery 53: 1328–1340; discussion 1340–1321, 2003.Google Scholar
  21. 21.
    Rowson, S., J. G. Beckwith, J. J. Chu, D. S. Leonard, R. M. Greenwald, and S. M. Duma. A six degree of freedom head acceleration measurement device for use in football. J Appl. Biomech. 27:8–14, 2011.PubMedGoogle Scholar
  22. 22.
    Rowson, S., and S. M. Duma. Brain injury prediction: assessing the combined probability of concussion using linear and rotational head acceleration. Ann. Biomed. Eng. 41:873–882, 2013.CrossRefPubMedPubMedCentralGoogle Scholar
  23. 23.
    Rowson, S., S. M. Duma, R. M. Greenwald, J. G. Beckwith, J. J. Chu, K. M. Guskiewicz, J. P. Mihalik, J. J. Crisco, B. J. Wilcox, T. W. McAllister, A. C. Maerlender, S. P. Broglio, B. Schnebel, S. Anderson, and P. G. Brolinson. Can helmet design reduce the risk of concussion in football? J. Neurosurg. 120:919–922, 2014.CrossRefPubMedGoogle Scholar
  24. 24.
    Signoretti, S., G. Lazzarino, B. Tavazzi, and R. Vagnozzi. The pathophysiology of concussion. PMR 3:S359–S368, 2011.CrossRefGoogle Scholar
  25. 25.
    Sullivan, S., S. H. Friess, J. Ralston, C. Smith, K. J. Propert, P. E. Rapp, and S. S. Margulies. Behavioral deficits and axonal injury persistence after rotational head injury are direction dependent. J. Neurotrauma 30:538–545, 2013.CrossRefPubMedPubMedCentralGoogle Scholar
  26. 26.
    Takhounts, E. G., S. A. Ridella, V. Hasija, R. E. Tannous, J. Q. Campbell, D. Malone, K. Danelson, J. Stitzel, S. Rowson, and S. Duma. Investigation of traumatic brain injuries using the next generation of simulated injury monitor (SIMon) finite element head model. Stapp Car Crash J. 52(52):1–31, 2008.PubMedGoogle Scholar
  27. 27.
    Unterharnscheidt, F., and L. S. Higgins. Traumatic lesions of brain and spinal cord due to nondeforming angular acceleration of the head. Tex. Rep. Biol. Med. 27:127–166, 1969.PubMedGoogle Scholar
  28. 28.
    Versace, J. A Review of the Severity Index. Warrendale: SAE, pp. 771–796, 1971.Google Scholar
  29. 29.
    Weaver, A. A., K. A. Danelson, and J. D. Stitzel. Modeling brain injury response for rotational velocities of varying directions and magnitudes. Ann. Biomed. Eng. 40:2005–2018, 2012.CrossRefPubMedGoogle Scholar
  30. 30.
    Society of Automotive Engineers (SAE). Instrumentation for Impact Test Part 1: Electronic Instrumentation, SAE J211/1. SAE, 2007.Google Scholar

Copyright information

© Biomedical Engineering Society 2015

Authors and Affiliations

  1. 1.Joint Biomechanics Lab, School of KinesiologyWestern UniversityLondonCanada
  2. 2.Injury Biomechanics and Aging Laboratory, Department of KinesiologyUniversity of WaterlooWaterlooCanada
  3. 3.Mechanical and Materials Engineering, Thompson Engineering BuildingWestern UniversityLondonCanada
  4. 4.Department of Allied Health SciencesThe University of North Carolina at Chapel HillChapel HillUSA

Personalised recommendations