| Tremor is clinically described as a rhythmical, involuntary oscillatory movement of a body part produced by reciprocally innervated antagonist muscles. The current clinical treatments include a collection of prescription drugs and, in especially debilitating or non-responsive cases, neurosurgery. The adverse side effects of both methods have inspired research into a less invasive alternative, the attenuation of tremor on the musculo-skeletal level. In the field of human-machine interaction, particularly that of wearable robotics, high strength-to-weight ratio actuators are required to maximize assistive and rehabilitative potential. Magnetorheological-based actuators can potentially achieve these high ratios and have the additional advantages of rapid response time and high fidelity control. Previous applications of magnetorheological dampers (MRDs) have been chiefly limited to vehicle shock absorbers and seismic vibration attenuators. The topic at hand is the feasibility of developing MRDs that would be functionally and cosmetically adequate for actuation of an upper limb tremor suppression orthosis. A Bingham plastic model is used to determine the MRD's functional characteristics, and experimental and finite element analysis data is presented to validate the mathematical model and assess the MRD's potential in the attenuation of tremorous motion. |
