Design and Analysis of Flexure Mechanisms for Human Hand Tremor Compensation

Abstract

Tremor is an involuntary action and a common problem for elderly people and other age groups to perform daily activities. To assist those people in conducting daily activities, suppressing hand tremors is necessary. A flexure mechanism system can be placed as a tabletop device on which the elbow can be positioned to compensate for the tremor. Using this methodology, in this paper, flexure-based mechanisms for the hand tremor are proposed to help people perform eating activities easily. Flexure mechanisms with three different connection arrangements are designed, modeled (as pseudo-rigid bodies), analyzed, and developed. Finite element analysis is conducted to verify the results of the pseudo-rigid models for passive conditions. An experimental setup is accessed for both passive and active schemes, consisting of two link mechanisms, having a precise one-DOF tremor generated at the end-effector of the experimental setup arm. Gyroscope sensors are used to monitor the tremor present. A series of experiments are conducted for two cases: when flexure mechanisms are connected passively and when flexure mechanism is connected actively. It was found that the flexure mechanism can compensate for the tremor in passive and active mode by approximately 75% to 90%, respectively.

Keywords

• Curved flexure
• hand tremor
• pseudo-rigid model
• passive and active tremor compensation