Biomechanical treatment for rest tremor of Parkinson's patient

Vibration absorbers are effective devices used to reduce the unwanted motion of a vibrating system. It is recently used to reduce the involuntary tremor of a Parkinson's patient. The absorber can be attached to the forearm of the patient hand. Such system can be excited at resonance frequencies reflecting the resting tremor due to the shoulder and elbow muscles activation. Two single absorbers are designed and tested numerically in reducing the involuntary tremor: the conventional absorber having its spring and damper connected in parallel and the elastic-damper absorber having its spring and damper connected in series. Both absorbers are designed to satisfy the tuning conditions at the fundamental frequency of the primary system with the same total mass. The conventional absorber causes 75.5-97.4%, 11.1-48.0% and 41.2-49.7% reduction at the shoulder, elbow and the wrist joints, respectively. However, the elastic-damper absorber causes 74.0-78.7%, 5.0-35.0% and 29.3- 45.8% at the same positions, respectively. The elastic-damper absorber can cause this reduction with a device of shorter length.