@inproceedings{fd48547216534c20a2ae0aeb4729b9ce,
title = "On the accuracy of low-cost motion capture systems for range of motion measurements",
abstract = "In this paper, we study low-cost motion tracking systems for range of motion (RoM) measurements in the tele-rehabilitation context using Augmented Reality. We propose simple yet effective extensions of the Microsoft Kinect SDK 2.0 skeleton tracking algorithm. Our extensions consist of temporal smoothing of the joint estimates as well as an intuitive, patient-specific adjustment of the bone lengths that is implemented as a quick, one-Time calibration performed by the therapist. We compare our system to the Kinect v1, the non-modified Kinect v2, a marker-based optical tracking system, and the clinical gold standard set by two subject-matter-experts using a goniometer. We study the accuracy of all systems in RoM measurement on the elbow joints. We quantitatively compare angular deviation from the expert measurements and perform analysis on statistical confidence. The results indicate, that the proposed personalized setup substantially outperforms all competing systems and effectively corrects for the systematic error of the skeleton tracking, particularly at full flexion. The improved system matched the observations of both experts with a mean error of 3:78° We conclude, that the proposed, personalized method for RoM measurement with Augmented Reality feedback is promising for tele-rehabilitation scenarios. Future work will investigate whether similar strategies can be applied to more complex joints, such as the shoulder.",
keywords = "Goniometer, Kinect, Optical tracker, Polaris Vicra, RoM, Tele-rehabilitation, Vicon",
author = "Kevin Yu and Roghayeh Barmaki and Mathias Unberath and Albert Mears and Joseph Brey and Chung, {Tae Hwan} and Nassir Navab",
note = "Funding Information: ACKNOWLEDGElbENTS This work was partially financed by European Community programme STEP (under contract n9CT090-110) and by Programa Mobilizador de CiGncia e Tecnologia (JNICT, Portugal) Publisher Copyright: {\textcopyright} 2018 SPIE.; Medical Imaging 2018: Imaging Informatics for Healthcare, Research, and Applications ; Conference date: 13-02-2018 Through 15-02-2018",
year = "2018",
doi = "10.1117/12.2293670",
language = "English (US)",
series = "Progress in Biomedical Optics and Imaging - Proceedings of SPIE",
publisher = "SPIE",
editor = "Po-Hao Chen and Jianguo Zhang",
booktitle = "Medical Imaging 2018",
}