C. Data collection
Vicon® T40 3D Motion Capture with 10 cameras were
used to capture the body posture of the subjects at 100Hz.
Two forceplates (AMTI® OR6-7) were placed front and back
to register the ground reaction force at 1000Hz. (Subjects
were asked to step on the forceplates one by one when they
walk across the walkway.) The cameras and forceplates were
time-synchronized.
39 reflective markers were placed on the subjects’ bodies.
Most of the markers were placed on the anatomical landmarks
of the caregivers along with the rest to form the rigid bodies to
track: head, left and right upper arms, left and right forearms,
left and right hands, upper trunk, pelvis, left and right thighs,
left and right shanks, left and right feet. Thus A 3D full body
model with 15 segments was constructed.