Design and Development of a Wearable Device with 250 Hz White-Noise Vibrotactile Stimulation for Tremor Reduction in Early-Stage Parkinson's Disease

Abstract

Introduction: Parkinson's disease is a progressive neurological disorder affecting more than 8.5 million people worldwide, with a prevalence that has doubled over the past 25 years. Hand tremor is one of its main motor symptoms, significantly impairing daily activities such as writing, eating, and object manipulation. Wearable assistive technologies represent a promising strategy to complement pharmacological and rehabilitation treatments, particularly in resource-limited settings such as Mexico.

Objective: To design and develop a functional wrist-worn wearable prototype to reduce hand tremors in individuals with early-stage Parkinson's disease through white-noise vibrotactile stimulation targeting 250 Hz, in order to improve their performance in daily activities.

Methodology: An applied biomedical engineering approach was followed across progressive stages: literature review, requirements analysis, conceptual and ergonomic design, electronic system design, and prototype development. The device integrates inertial sensors (accelerometer and gyroscope), vibration actuators, and a microcontroller. The 250 Hz target frequency was selected based on scientific evidence: Cabral et al. (2024) demonstrated it was the only frequency that reduced both tremor peak power and amplitude even after stimulation ended. The mechanism is based on stochastic resonance: white-noise vibration introduces sub-threshold sensory noise that disrupts the abnormal sensorimotor feedback loop generating Parkinsonian tremor. The structure was fabricated using 3D printing, prioritizing portability, comfort, and low cost.

Results: A functional prototype was assembled using accessible electronic components. Preliminary tests confirmed correct sensor-actuator communication, stable signal acquisition, and structural integrity. CAD modeling optimized component distribution and ergonomics. The electronic architecture provides the foundation for future real-time tremor detection algorithm implementation.

Conclusions: The project demonstrated the feasibility of a wearable device using 250 Hz white-noise vibrotactile stimulation for Parkinsonian tremor reduction, grounded in recent scientific evidence. The prototype represents an accessible complement to conventional therapies. Future work includes clinical validation, miniaturization, battery optimization, and adaptive control algorithm development.