Accuracy Assessment of a 2D Phone Application with 3D Motion Capture
Faculty Mentor Information
Dr. Joshua P. Bailey, University of Idaho
Presentation Date
7-2025
Abstract
2D motion capture could be a promising improvement in rural medicine for both screening and monitoring movement quality. The purpose of this project is to assess the accuracy of a Boise-based functional movement assessment phone app in measuring movement mechanics; namely asymmetries, limitations, and providing functional movement screen scores. 20 participants (20.6 ± 1.7 yrs, 1.73 ± 0.08 m, 78.2 ± 17.8 kgs) performed lateral lunges, single-leg standing balance, hip hinge, and an overhead squat. Each participant performed between two and four trials of each task, for a total of 66 trials for comparison. The movement app collected frontal plane movement using an iPad, while the Vicon motion capture system collected 3D motion in tandem. Ranges of motion and peak angles were calculated for each joint and plane of interest The measurements from the phone app were extracted from their platform, following their proprietary calculations. 3D motion capture was extracted using custom Matlab codes used to assess the same variables extracted by the phone app. To assess the accuracy of the 2D apps measurements from the single camera, the values were compared using paired t-tests to those measured from the 3D motion tracking system.
Accuracy Assessment of a 2D Phone Application with 3D Motion Capture
2D motion capture could be a promising improvement in rural medicine for both screening and monitoring movement quality. The purpose of this project is to assess the accuracy of a Boise-based functional movement assessment phone app in measuring movement mechanics; namely asymmetries, limitations, and providing functional movement screen scores. 20 participants (20.6 ± 1.7 yrs, 1.73 ± 0.08 m, 78.2 ± 17.8 kgs) performed lateral lunges, single-leg standing balance, hip hinge, and an overhead squat. Each participant performed between two and four trials of each task, for a total of 66 trials for comparison. The movement app collected frontal plane movement using an iPad, while the Vicon motion capture system collected 3D motion in tandem. Ranges of motion and peak angles were calculated for each joint and plane of interest The measurements from the phone app were extracted from their platform, following their proprietary calculations. 3D motion capture was extracted using custom Matlab codes used to assess the same variables extracted by the phone app. To assess the accuracy of the 2D apps measurements from the single camera, the values were compared using paired t-tests to those measured from the 3D motion tracking system.