Design and Construction of an Artificial Thumb Prosthetics Controlled by Index Finger

Abstract

The main scope of this article is to present design and fabrication of a simple active robotic prosthetics thumb which is activated by the motion of the index finger. In the proposed single degree-of-freedom mechanism output signal of the strain gauge attached to the index finger is utilized to activate the driving mechanism of the assistive robotic thumb. Stepper motor is employed as a driving system in the proposed mechanism. Experimental investigation was performed to evaluate the performance of the constructed prototype for catching, grasping, and lifting activities of various objects with different weights and shapes. The experimental results indicate very good performance of the proposed artificial thumb prototype and illustrate the assistive system's action is very compliant to the motion of the able-bodied hand. As a result, it can be mentioned that the key factor for successful design of a portable in-home robotic-assistive prosthetics is to consider the anatomy compliancy in actuation system guarantees the opportunity of successful post-stoke treatment.