Exiii, a Japanese prosthetics company, has developed a smartphone-connected, EMG-controlled prosthetic arm called the handiii COYOTE. The device was developed as a low cost, highly functional myoelectric arm, but ended up as a pretty stunning piece of hardware which can be manufactured for less than $300.

The handiii was developed with three core design principles in mind:
-Outsource the sensor processing and control algorithms to a standard smartphone
-Reduce the number of motors needed to one per finger (rather than one per joint)
-Use 3D printing to reduce manufacturing costs, and enable easy repair and customization

The handiii transmits EMG sensor information from the arm to a smartphone using a wireless communication link embedded under the prosthesis. The smartphone algorithms interpret these signals to control the arm. Exiii are quick to point out that these algorithms are based on work by Mr. Noritaka Kawashima of the National Rehabilitation Center for Persons with Disablities, and Mr. Masahiro Yoshikawa of Nara Institute of Science and Technology in Japan, for their motorized prosthetic hand called the Finch.

The handii allows the wearer to toggle through a range of programmable grips such as a pinch grip, five fingered grasps etc. via a small button on the elbow. Though it has been knocking around since late 2013 as a prototype device, the latest version of the arm has a much sleeker finish and wireless functionality. Exiii has enlisted two expert user evangelists to assist them with testing and developing the arm which needs to be custom-made to fit varying arm sizes.

Without a doubt the most striking aspect of this device is its low cost and beautiful design. It is not surprising that the team have won a number of prestigious design awards for the handiii and envisage a wide range of customizable, 3D printable textured skins for their device in the future.

source:University Saarland