Schall et al.
Publisher: Taylor & Francis Journal: Ergonomics DOI: http://dx.doi.org/10.1080/00140139.2015.1079335
Accuracy and repeatability of an inertial measurement unit system for field-based occupational studies * Mark C. Schall, Jr., Ph.D. Auburn University Department of Industrial and Systems Engineering 3301 Shelby Center for Engineering Technology Auburn, AL 36849 Email: [email protected] Nathan B. Fethke, PhD University of Iowa Department of Occupational and Environmental Health S347 College of Public Health Building (CPHB) Iowa City, IA 52242 Phone: (319) 467-4563 Email: [email protected] Howard Chen, MS University of Iowa Department of Mechanical and Industrial Engineering 3131 Seamans Center for the Engineering Arts and Sciences Iowa City, IA 52242 Phone: (319) 335-4996 Email: [email protected] Sakiko Oyama, PhD, ATC University of Texas at San Antonio Department of Health and Kinesiology One UTSA Circle, Main Building Room 3.324 San Antonio, TX 78249 Phone: (210) 458-5435 E-mail: [email protected] David Douphrate, PhD, MPT, MBA University of Texas School of Public Health, San Antonio Regional Campus Department of Epidemiology, Human Genetics and Environmental Sciences 7411 John Smith Drive, Suite 1100 San Antonio, TX 78229 Phone: (210) 562-5508 E-mail: [email protected] * Corresponding author Submitted to Ergonomics
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Schall et al.
Initial Peer Review Submission Date: December 10, 2014 Revision Submission Date: June 15, 2015 Acknowledgements This work was supported by three extramural research grants of the Centers for Disease Control and Prevention / National Institute for Occupational Safety and Health (NIOSH) including the Great Plains Center for Agricultural Health and Safety (Grant no: 5U54OH007548-13A), the High Plains Intermountain Center for Agricultural Health (Grant no: 2U54OH008085-08), and a pilot project research training grant from the Heartland Occupational Safety and Health Research Center (Grant no: 5T42OH008491-08).
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Schall et al.
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Accuracy and repeatability of an inertial measurement unit system for field-based occupational studies Mark C. Schall, Jr. a, Nathan B. Fethke b, Howard Chen b, Sakiko Oyama c, David I. Douphrate d a
Department of Industrial and Systems Engineering, Auburn University, Auburn, AL, USA Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA, USA c Department of Kinesiology, Health, and Nutrition, University of Texas at San Antonio , San Antonio, TX, USA d Department of Epidemiology, Human Genetics and Environmental Sciences, University of Texas School of Public Health,, San Antonio, TX, USA b
The accuracy and repeatability of an inertial measurement unit (IMU) system for directly measuring trunk angular displacement and upper arm elevation was evaluated over eight hours (i) in comparison to a gold-standard, optical motion capture (OMC) system in a laboratory setting, and (ii) during a field-based assessment of dairy parlor work. Sample-tosample root mean square differences (RMSD) between the IMU and OMC system ranged from 4.1°-6.6° for the trunk and 7.2°-12.1° for the upper arm depending on the processing method. Estimates of mean angular displacement and angular displacement variation (difference between the 90th and 10th percentiles of angular displacement) were observed to change
Publisher: Taylor & Francis Journal: Ergonomics DOI: http://dx.doi.org/10.1080/00140139.2015.1079335
Accuracy and repeatability of an inertial measurement unit system for field-based occupational studies * Mark C. Schall, Jr., Ph.D. Auburn University Department of Industrial and Systems Engineering 3301 Shelby Center for Engineering Technology Auburn, AL 36849 Email: [email protected] Nathan B. Fethke, PhD University of Iowa Department of Occupational and Environmental Health S347 College of Public Health Building (CPHB) Iowa City, IA 52242 Phone: (319) 467-4563 Email: [email protected] Howard Chen, MS University of Iowa Department of Mechanical and Industrial Engineering 3131 Seamans Center for the Engineering Arts and Sciences Iowa City, IA 52242 Phone: (319) 335-4996 Email: [email protected] Sakiko Oyama, PhD, ATC University of Texas at San Antonio Department of Health and Kinesiology One UTSA Circle, Main Building Room 3.324 San Antonio, TX 78249 Phone: (210) 458-5435 E-mail: [email protected] David Douphrate, PhD, MPT, MBA University of Texas School of Public Health, San Antonio Regional Campus Department of Epidemiology, Human Genetics and Environmental Sciences 7411 John Smith Drive, Suite 1100 San Antonio, TX 78229 Phone: (210) 562-5508 E-mail: [email protected] * Corresponding author Submitted to Ergonomics
1
Schall et al.
Initial Peer Review Submission Date: December 10, 2014 Revision Submission Date: June 15, 2015 Acknowledgements This work was supported by three extramural research grants of the Centers for Disease Control and Prevention / National Institute for Occupational Safety and Health (NIOSH) including the Great Plains Center for Agricultural Health and Safety (Grant no: 5U54OH007548-13A), the High Plains Intermountain Center for Agricultural Health (Grant no: 2U54OH008085-08), and a pilot project research training grant from the Heartland Occupational Safety and Health Research Center (Grant no: 5T42OH008491-08).
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Schall et al.
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Accuracy and repeatability of an inertial measurement unit system for field-based occupational studies Mark C. Schall, Jr. a, Nathan B. Fethke b, Howard Chen b, Sakiko Oyama c, David I. Douphrate d a
Department of Industrial and Systems Engineering, Auburn University, Auburn, AL, USA Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA, USA c Department of Kinesiology, Health, and Nutrition, University of Texas at San Antonio , San Antonio, TX, USA d Department of Epidemiology, Human Genetics and Environmental Sciences, University of Texas School of Public Health,, San Antonio, TX, USA b
The accuracy and repeatability of an inertial measurement unit (IMU) system for directly measuring trunk angular displacement and upper arm elevation was evaluated over eight hours (i) in comparison to a gold-standard, optical motion capture (OMC) system in a laboratory setting, and (ii) during a field-based assessment of dairy parlor work. Sample-tosample root mean square differences (RMSD) between the IMU and OMC system ranged from 4.1°-6.6° for the trunk and 7.2°-12.1° for the upper arm depending on the processing method. Estimates of mean angular displacement and angular displacement variation (difference between the 90th and 10th percentiles of angular displacement) were observed to change
