A markerless estimation of the ankle-foot complex 2D kinematics during stance

Surer E., CEREATTI A., GROSSO E., DELLA CROCE U.

GAIT & POSTURE, vol.33, no.4, pp.532-537, 2011 (SCI-Expanded, Scopus) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 33 Issue: 4
  • Publication Date: 2011
  • Doi Number: 10.1016/j.gaitpost.2011.01.003
  • Journal Name: GAIT & POSTURE
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.532-537
  • Keywords: Markerless, Human movement analysis, 20 joint kinematics, Ankle-foot complex, MOTION CAPTURE, MOVEMENT
  • Middle East Technical University Affiliated: No

Abstract

A markerless technique is proposed and applied to estimate the two-dimensional joint kinematics of the shank and foot complex during the stance phase. Image sequences were acquired with a single camera from three healthy subjects while walking barefoot and with socks. Automatic segmentation of the shank and foot was performed to isolate the moving body from the background. A multi-rigid body model for the shank and foot complex, with the relevant segment anatomical axes, was defined and an image cross-correlation technique was applied to detect the anatomical axes locations throughout the movement. The proposed markerless technique was validated by acquiring the same trials also with a stereophotogrammetric marker-based system and a simple marker set. Differences in the joint kinematics estimates obtained with the two techniques fall in most cases within the intra-subject variability showing that, in selected applications, the markerless technique may replace more expensive and more experimental time demanding marker-based techniques. (C) 2011 Elsevier B.V. All rights reserved.