In [68], a trousers-like power assist wear for locomotion assistance
is presented. The pneumatic actuators are composed by balloon
and circular actuators which are attached by a hook-and-loop
fastener between the outer and inner wears. According to the prototype
figure, there are three actuators mounted on each leg: one
on the knee, one on the rear of the thigh and one on the rear of the
shank.
The expansion forces from actuators are applied to the knee
joint through the extensible cloth attached on the outer wear.
During leg swing, the inner pressure of actuators is decreased to
make the leg move freely; during stance phase, the pressure is kept
high; and when the heel leaves/contacts the ground, the pressure
is increased. The gait events are detected with insole sensors. The
torque executed on the knee is affected by the quality of the balloon
and circular actuators, which are characterized to be linear to the
knee angle.
Experiments testing stair ascent and descent tasks were carried
out with one subject. The subject’s EMG showed decreased peaks
during walking upstairs, but some extra peaks were recorded while
walking downstairs