EWA-Background and Introduction

Arm injuries and arm muscles dysfunction are common conditions that affect daily activities. Many orthotics exist to assist with recovery from such injuries. These can perform a variety of functions from providing rigid support to assisting or constraining motion. A popular constrained motion is flexing the arm. The purpose of this project is to develop a mechanism that allows the user to perform controlled hand rotation by bending his/her arm. Specifically, this mechanism would passively supinate the hand as the user flexes his/her arm.

Figure 1. Human Arm Motions [4]

This mechanism is meant to be used by patients trying to recover or maintain the coordination required to autonomously rotate the wrist. The mechanism would also be useful for patients who are able to bend their arm, but cannot rotate their hand due to a nervous system condition. Passive wrist rotation could help such patients by enabling them to perform daily activities like eating by themselves again.