Biomedical Engineering Reference
In-Depth Information
Fig. 9.2
Powered shoes
system, and were put in a backpack. The active roller skate was designed to fit in the
sole. It has three rollers, two of which are connected by a timing belt and driven by a
motor. The diameter of each roller is 16 mm and overall height of the mechanism is
20 mm. The overall weight of the mechanism is 700 g, roughly the same as a hiking
shoe. The mechanism allows the user to walk at a speed of 600 mm/s. Figure
9.2
shows overall view of the Powered Shoes.
The major limitation of this system was that the direction of the traction force
generated by the rollers is identical to the shoe, which only allows the walker in a
straight line.
9.2.3 String Walker
The String Walker is a locomotion interface based on eight strings actuated by motor-
pulley mechanisms mounted on a turntable [
16
]; see Fig.
9.3
. The mechanism enables
omni-directional walking. The device also allows the walker to perform various gait
patterns, such as side-walking.
Four strings are connected to each shoe and are actuated by motor-pulley mech-
anisms. The maximum tension of each string is 25 Kgf. A touch sensor in the shoe
detects stance phase and swing phase of walking. The signal is wirelessly transmitted
to a host computer. No force is applied to the shoe while it is in the swing phase.
