Title Calibration-free shoulder kinematics using single and dual asynchronous RGB-D cameras
Authors Abromavičius, Vytautas ; Griškevičius, Julius ; Matuzevičius, Dalius ; Maknickas, Algirdas ; Plonis, Darius ; Maskeliūnas, Rytis
DOI 10.1109/ACCESS.2026.3659738
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Is Part of IEEE Access.. Piscataway, NJ : IEEE. 2026, vol. 14, p. 17381-17394.. ISSN 2169-3536
Keywords [eng] computer vision ; human pose estimation ; motion capture ; pose estimation ; single person pose estimation
Abstract [eng] This study experimentally evaluates whether shoulder joint kinematics can be accurately reconstructed using calibration free asynchronous RGB-D cameras under rehabilitation relevant conditions. We present a markerless framework that jointly learns temporal alignment, geometric consistency, and pose reconstruction using continuous-time modeling based on Neural Ordinary Differential Equations and implicit representations, eliminating the need for hardware synchronization or manual camera calibration. The system was validated in a controlled laboratory setting against a BTS Smart-DX optical motion capture reference during five clinically relevant shoulder movements. Performance was assessed for single- and dual-camera configurations. The dual-camera setup achieved a mean joint position error of 15.4 ± 2.8 mm with low temporal jitter (5.9 ± 0.7 mm), while the single-camera configuration showed reduced accuracy and higher sensitivity to occlusion. The results demonstrate that calibration-free asynchronous RGB-D systems can provide feasible shoulder kinematics, with a clear accuracy–complexity trade-off between single-and dual-camera deployments.
Published Piscataway, NJ : IEEE
Type Journal article
Language English
Publication date 2026
CC license CC license description