Low-Cost Textile Myoelectric Control of Knee-Ankle-Foot-Orthosis

The poorest populations in the world have the highest prevalence of lower limb disabilities, and lack of access to healthcare prevents many from lifting themselves out of poverty. This is particularly true for the large population of poliomyelitis-affected inhabitants of India, whose quality of life would benefit substantially from the provision of affordable, yet modern, dynamic knee-ankle-foot orthoses to assist in ambulation. To this end, this paper reports a study into the use of a low-cost, textile-based sensor interface for the myoelectric control of lower limb orthoses in restoring gait function. It reports experiments examining the accuracy with which gait events in the healthy limb (e.g., heel strike, toe-off) can be detected through the textile interface, with a view to triggering discrete control modes of a smart orthosis (i.e., knee lock and release) to support the atrophied limb during walking. Results show that prediction accuracy through the proposed interface (~ 70%) approaches that of more traditional medical-grade sensors, despite its substantially lower cost.