Wearable Sensors for Balance, Gait, and Mobility

Instability and lack of fluid mobility during daily activities are often prevalent among older adults and those with neurodegenerative disorders due to the combined effects of age-related changes in the body and the impact of neurodegenerative conditions on motor function. Parkinson's Disease stands out among these disorders due to its high prevalence. Consequently, individuals with this affliction face a considerable risk of experiencing falls, a situation which, in its worst forms, can lead to severe injuries or even mortal consequences. To assess instability and poor mobility, various methods have been devised. Traditionally, tools and methods such as observational assessments and bespoke lab equipment such as instrumented walkways were employed to gauge these issues. However, observational assessments can be unreliable and less accessible, while bespoke lab equipment comes with substantial drawbacks such as being expensive, being large in size, and being restricted to specialised lab environments. Therefore, modern strategies emphasise the development of more cost-efficient, broadly accessible methods. This has catalysed the rise of wearable technology as a potent toolset for assessing these motion-related difficulties. This book chapter provides an in-depth exploration of three prominent wearable devices often deployed in the evaluation of stability and mobility deficits: Inertial Measurement Units (IMUs), Insole Pressure Sensors (IPS), and Surface Electromyography (sEMG). Each of these wearables is evaluated for its proficiency in quantifying balance, gait, and overall mobility within, and beyond, the confines of the lab. The chapter also underscores the importance of shifting future research focuses on the use of smartphones as IMU devices placed in the individual's pocket. This approach has been increasingly recognized for its potential in balance and gait analysis, showing promising results, where among all methods discussed and evaluated in this chapter, this technique stands out as the most cost-effective and least intrusive, displaying impressive efficacy in both healthy and pathological populations.