The aim of this study was to assess the precision and accuracy of an action sport camera (ASC) system (4 GoPro Hero3+ Black) by comparison with a commercial motion capture (MOCAP) system (4 ViconMX40). Both systems were calibrated using the MOCAP protocol and the 3-dimensional (3D) markers coordinates of a T-shaped tool were reconstructed, concurrently. The 3D precision was evaluated by the differences in the reconstructed position using a Bland–Altman test, while accuracy was assessed by a rigid bar test (Wilcoxon rank sum). To examine the accuracy of the action sport camera with respect to the knee flexion angles, a jump and gait task were also examined using 1 subject (Wilcoxon rank sum). The ASC system provided a maximum error of 2.47 mm, about 10 times higher than the MOCAP (0.21 mm). The reconstructed knee flexion angles were highly correlated (r 2 > .99) and showed no significant differences between systems (<2.5°; P > .05). As expected, the MOCAP obtained better 3D precision and accuracy. However, the authors show such differences have little practical effect on reconstructed 3D kinematics.
Gustavo Ramos Dalla Bernardina, Tony Monnet, Heber Teixeira Pinto, Ricardo Machado Leite de Barros, Pietro Cerveri and Amanda Piaia Silvatti
Melissa M.B. Morrow, Bethany Lowndes, Emma Fortune, Kenton R. Kaufman and M. Susan Hallbeck
, Caravaggi P . Validation of the angular measurements of a new inertial-measurement-unit based rehabilitation system: comparison with state-of-the-art gait analysis . J Neuroeng Rehabil . 2014 ; 11 : 136 . PubMed doi: 10.1186/1743-0003-11-136 25212257 17. Bouvier B , Duprey S , Claudon L
Moataz Eltoukhy, Christopher Kuenze, Jeonghoon Oh, Eryn Apanovitch, Lauren Butler and Joseph F. Signorile
– 2H ). Table 1 Between-System Comparison of Kinematic Variables During the Stance and Early Deceleration Phases 3DMA, mean (SD) Kinect, mean (SD) P value Absolute meandifference Relativemeandifference SEM (95% CI) Agreement ICC (95% CI) Consistency ICC (95% CI) Correlation r (95% CI) Stance phase