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Published on: March 14, 2017
A Mobile Application to Measure Trunk Flexion Angles in Lifting Tasks
Jeff M Barrett1, Thomas Karakolis2, Jack P Callaghan1
1Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada.
Abstract:
Occupational Abstract The aim of this project was to develop and test an application capable of quickly and repeatedly measuring trunk flexion angles during sagittal plane lifting tasks. The developed application uses the built-in accelerometer in mobile devices to approximate trunk flexion angle, as the user follows an operator as they perform a lift. A black line is superimposed over the camera feed, allowing the user to approximate the angle of inclination of a line connecting the operator's seventh cervical and first sacral vertebrae-thereby estimating the trunk flexion angle. The magnitude of this angle and its velocity have been linked to the development of occupational low back pain; thus the application provides ergonomists a more refined means of screening tasks beyond currently available survey tools.

