Flexible and Self-Powered Wearable Sensors for Tremor Monitoring in Parkinson'S Disease: Recent Advances in Materials and Device Architectures

Abstract

Parkinson’s disease (PD) is a progressive neurodegenerative disorder where tremor remains one of the most prominent anddisabling motor symptoms. Traditional clinical rating scales for disease severity rely on clinician observation and patient self-report, often failing to capture the dynamic and continuous nature of tremors in daily life. This drives the development of objectivemonitoring technologies, such as wearable sensors, for more accurate evaluation of PD severity. However, many existing systemsuse rigid materials that lack the mechanical compliance and skin conformability required for stable biointegration. This reviewsummarizes advances in flexible wearable sensors for PD tremor assessment from material innovations to a device engineeringperspective, covering inertial measurement units (IMUs), electromyography (EMG), and emerging self-powered systems such astriboelectric (TENG) and piezoelectric nanogenerators (PENG). This review highlightshow functional materials, microstructuraldesign, and device architectures govern sensing mechanisms and performance, with particular emphasis on the transition fromrigid components to soft, skin-interfaced technologies. Recent patent activity reflects a shift toward multimodal, wireless, andclinically integrated platforms. Despite progress, challenges remain, including motion artifacts, durability, and limited large-scale clinical validation. Integration of flexible materials, self-powered designs, and AI-driven analytics enables continuous,personalized monitoring, moving closer to real-world clinical deployment and improved patient care.