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Helen Hayes marker set. To track the motion of the subject, 19 reflective markers with a diameter of 20 mm were affixed to specified locations. The hip joint center (HJC), knee joint center (KJC) and ankle joint center (AJC) of both legs were calculated using the Cortex software package.

Helen Hayes marker set. To track the motion of the subject, 19 reflective markers with a diameter of 20 mm were affixed to specified locations. The hip joint center (HJC), knee joint center (KJC) and ankle joint center (AJC) of both legs were calculated using the Cortex software package.

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For robot-assisted rehabilitation and assessment of the patients with motor dysfunction, the parametric generation of their normal gait as the input for the robot is essential to match with the features of the patient to a greater extent. In addition, the gait needs to be in three-dimensional space, which meets the physiological structure of the hu...

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... the coordinates of the world (van Kammen et al. 2016), calibrated by a motion capture system. A homogeneous coordinate transformation was performed to translate the position of the ACP ( Meuleman et al. 2016;van Asseldonk and van der Kooij 2012) to the coordinates of the hip joint, {H}, following which the features of the ACP in {H} were analyzed (Fig. 5). The AJA and ACP of all the subjects were obtained and normalized as a function of the gait cycle percentage, which was 0% corresponding to the initial contact of the concerned leg. The initialcontact and toe-off events were detected by a phase detection method ( Zeni et al., 2008). The FPA was calculated as the angle between the foot ...
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... this study, the coordinates of the pelvis, {P}, were used to establish {H} because the directions of the axes of the two coordinates were the same. The positions of the markers on the pelvis were used to establish {P}. The origin was the middle point from the R.Asis to the L.Asis in the Helen Hayes marker set as shown in Fig. 5. The positive direction of the y axis was directed from the R.Asis to the L.Asis. The z axis was directed inferiorly as the vector that intersects the y axis and perpendicular to the plane containing the L.Asis, R.Asis and sacral markers. The x axis of the pelvis (directed anteriorly) was determined as the cross-product of the y and z ...

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