Design and testing of a novel, low-cost, low-voltage, functional electrical stimulator

This paper presents the design of a novel, noninvasive, low cost (<; $70), low voltage (<; 46 V maximum output, 3 V power supply), functional electrical stimulation (FES) circuit aimed at upper-limb stroke rehabilitation. The novel component of the circuit is the unique topology. This circuit uses a boost converter in series with an H-bridge to produce the required biphasic pulses. The stimulator is controllable using a range of different microcontrollers. The low voltage used makes this circuit inherently safer than circuits which use much higher voltages, up to 500 V. The circuit has been successfully tested on the bicep muscles of one healthy subject and is capable of inducing flexion of the elbow with as little as 12 V.