Characteristics of the muscle activities for the elderly wearing the lower limb orthosis during gait on the treadmill

We have developed a gait assistance device for lower limb with a pneumatic rubber actuator, which is intended to assist and enhance lower limb muscular activities. Compared to other gait assistive devices being developed by other researchers, our device is designed especially for aged people and intended only for slight assistance so that the subjects can keep their muscular strength. For this purpose, we are investigating appropriate amount of power pattern of the device and investigating the muscular activities with and without the orthosis in gait motion on treadmill. To find out the characteristics of the muscle activities, we analyzed the gait motion of the subject and flexing and extending motion of the knees and measured muscular power in the lower limbs. The subjects wearing the lower limb orthosis were instructed to perform gait on the treadmill for monitoring of electromyogram and muscular activities. We used the C8051F Target Board (SILICON LABORATORIES, Inc., USA) for the orthosis control. The air pressure of the pneumatic actuator was varied from one kgf/cm 2 to four kgf/cm 2 to find the most suitable air pressure. Through this study, we expect to find the effect of the lower limb orthosis in the gait motion and muscular activities along with the most suitable air pressure in the pneumatic actuator of the orthosis for the enhancement of muscular power for the elderly.