Classifying Gait Alterations Using an Instrumented Smart Sock and Deep Learning

Abstract

This paper presents a non-invasive method of classifying gait patterns associated with various movement disorders and/or neurological conditions, utilising unobtrusive, instrumented socks and a deep learning network. Seamless instrumented socks were fabricated using three accelerometer embedded yarns, positioned at the toe (hallux), above the heel and on the lateral malleolus. Human trials were conducted on 12 able-bodied participants, an instrumented sock was worn on each foot. Participants were asked to complete seven trials consisting of their typical gait and six different gait types that mimicked the typical movement patterns associated with various movement disorders and neurological conditions. Four Neural Networks and an SVM were tested to ascertain the most effective method of automatic data classification. The Bi-LSTM generated the most accurate results and illustrates that the use of three accelerometers per foot increased classification accuracy compared to a single accelerometer per foot by 11.4%. When only a single accelerometer was utilised for classification, the ankle accelerometer generated the most accurate results in comparison to the other two. The network was able to correctly classify five different gait types: stomp (100%), shuffle (66.8%), diplegic (66.6%), hemiplegic (66.6%) and "normal walking" (58.0%). The network was incapable of correctly differentiating foot slap (21.2%) and steppage gait (4.8%). This work demonstrates that instrumented textile socks incorporating three accelerometer yarns were capable of generating sufficient data to allow a neural network to distinguish between specific gait patterns. This may enable clinicians and therapists to remotely classify gait alterations and observe changes in gait during rehabilitation.

Functional performance of low-cost electronic yarn for E-textiles

“…5 Most importantly, studies have integrated vibration, motion, and accelerometer sensors to produce e-yarns to detect fall or near fall, monitor vibration in the index finger and palm to classify gait alterations, respectively. [6][7][8] Other notable e-yarns are the development of light-emitting diode (LED) e-yarns, which are embedded into clothing for applications in health care, art, fashion, entertainment, and road safety (to make pedestrians visible). 9 LED e-yarns are usually fabricated by embedding LEDs into thin wires or conductive yarns to produce light when supplied with an external source of power.…”