J151024 Decision technique of the most suitable placement of the stimulation electrode for limbs control using surface electrical stimulation : Design of a pulse select circuit selecting the most suitable electrodes from many electrodes

Precise motor point stimulation is needed for efficient functional electrical stimulation (FES) because the stimulation of the motor point makes the muscle to contract the most. However physical therapists have difficulties of determining the position of motor point, because the position of motor point is different about 20% of muscle length among individuals. Therefore the purpose of this paper is to develop the automated FES electrodes positioning system which can stimulate the motor point precisely. This research deals with this purpose by developing the pulse select circuit, which can allocate FES stimuli to the multiple arbitrary electrodes. Therefore this circuit can search the most efficient pattern of electrodes positions by selecting stimulating electrodes in various patterns. Thus developed circuit can change position and area of stimulation at once: a wide variety of muscles are applicable. Moreover, developed circuit can be applied to other bio-instrumentation system which searches the best stimulation position. The developed pulse select circuit consists of a microcomputer, demultiplexers and photo-MOS relays, and it can select one arbitrary FES output line out of four output lines, and assign the selected output line to multiple arbitrary electrodes.