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

2011-04-01
Sürer, Elif
GROSSO, Enrico
DELLA CROCE, Ugo
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.

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Citation Formats
E. Sürer, E. GROSSO, and U. DELLA CROCE, “A markerless estimation of the ankle-foot complex 2D kinematics during stance,” GAIT & POSTURE, pp. 532–537, 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/31309.