Parkinsons Disease: Tremor Suppression With Wearable Device

Parkinson’s Disease (PD) is a neurodegenerative disorder that affects nearly a million people in the United States. Hand tremors are a well-known symptom associated with PD and result in anxiety, frustration, and malnutrition. While there is no cure, several approaches attempt to treat the symptoms. Many are invasive, including the use of pharmaceuticals and surgery [1]. Noninvasive technologies are often cumbersome and do not address the conspicuous nature experiencing tremors in public. This study is motivated by design criteria established from previous research [2], with a goal of an affordable, purely mechanical solution. In both cases, human subject testing echoed lab tests in effective tremor reduction. The extension to a wearable device gives the user the ability to hold or handle any object, or no object, with a significant reduction in tremor. Two separate wearable devices were tested for effectiveness while the simulated user ‘held’ two different objects to simulate different applications. Biomechanical modeling of the human hand informed the development of an adjustable mechanical hand-tremor system for testing. Models of the devices and the hand-device interface were used to simulate the dynamic response of the coupled systems. Each device was secured to the mechanical hand-tremor system and harmonic stimulus and response data was collected over the range of typical tremor frequencies. The results demonstrate the versatility of both designs for reducing the oscillations associated with tremors. The Ratio of Reduction (RoR) was defined to compare the tremor amplitude of the hand-tremor system with and without the device. Both designs were considered effective for each object with a max RoR of 28.09 for Device A and a max RoR of 99.32 for Device B.