7
● Yielding function
By having the heel land first, an amputee can
slowly flex the knee while applying body weight
to the knee. After getting familiar with the
yielding function, he or she can perform various
acts such as descending a slope and stairs.
Note: Hybrid Knee is intended to assist capability of a person who uses a
prosthesis. Without proper gait training, nobody is able to descend a
steep slope or stairs.
In order to make yielding function effective, be
sure to strike the floor with the heel first. If you
strike the floor with the toe first, hydraulic
resistance is turned off and the body weight
cannot be supported. There is a risk that knee
buckling may take place, causing falling-down. For safe use, fully understand
the operational principle and proper walking method, and provide the
amputee with instructions.
J
See
Fig. 4 Stairs
POINT 1
(page 15).
Time for one cycle
Stance phase
OFF
OFF
ON
8°
Swing phase
8°
2-4
Swing Phase Control
The microprocessor
calculates the time for
one walking cycle by
using data on knee joint
flexion as detected by
the proximity sensor.
Also, this microproces-
sor memorizes for each
amputee the adjusting
data on the maximum
10 stages which consist
of cadence and reaction
force of the pneumatic
cylinder. When cadence changes, the microprocessor commands the step-
ping motor to activate the needle valve immediately so that a swing speed of
the prosthesis is selected.
Fig. 5
WARNING
