Open Source Printed Prosthetics

Published by Bram Geenen on 21 September 2015

One of my favourite examples of Open Making in action is the Exiii Hackberry - a 3D printable myoelectric prosthetic arm created by Exiii Inc, a Japanese robotics company that specialises in bionic arms.

The hand works by detecting when nerve and muscle tissue is stimulated by signals from the brain and sends that data to an onboard micro controller to translate into hand and arm movements. The system enables users of the prosthesis to open and close the hand and even control individual fingers.

After the initial designs were released as open source files the project created a stir on social media site Reddit. This resulted in further collaborative development of the Hackberry by a community, including highly skilled engineers, designers, medics and manufacturing companies.

Within a week of the project being posted on Reddit over a million people had heard about it. One of those people was Matt Cashman, whose brother Ryan had recently lost both his hands in an awful work accident at an oil rig in Texas.

In just two weeks a team of 40 individuals had formed to innovate the Hackberry to fit Ryan’s specifications. This team included individuals from a broad range of backgrounds, with the combined skills to make any R&D department jealous.

Take Max for example - Max is a mechanical engineer heading to a top university next fall. Max had a summer job that was not engineering related, and missed engineering and designing.
Contributing to the development of the Hackberry enables Max to grow his knowledge and skills, and work under the wing of more senior engineers.

There’s also a 3D company who jumped in to make the necessary 3D scans of Ryan’s arms, and a manufacturing company that can CNC mill the components out of solid aluminium.

Among the team is Neela, a hand surgeon (plastic) from Melbourne, who works in the team that did the first successful hand transplant in Australia. Neela had never done any engineering or making before, and never touched a 3D printer. Now her knowledge and expertise, as input for the engineers and designers on the team, is of incredible value to the newly designed product. As Neela expressed, “the power of the internet is something people talk about, sometimes you see it in action and that is really powerful!”.

Currently the original Hackberry design is spreading into multiple versions for specific use cases, and the technology is being enhanced with open source software so as to become self learning, to automate amputees movements.

A hospital in India now has plans to provide 20.000 people on their waiting list with the prosthetics because of their high quality and low cost.

This one story serves to illustrate the important part that open source hardware collaborations could play in transforming people’s lives for the better int he near future.

Other great examples of open hardware projects include:
The OpenROV underwater exploration vehicle
Ultrascope by Open Space Agency
PLEN2 - a small 3D printable humanoid robot

In studying these examples over recent years through my work at, my general reflections would be that:

  • more and more startups realise that Open Hardware is a way to grow a community that provides goodwill, engaged users and customers, an external R&D department and help in spreading the product.

  • more and more Open Hardware projects are moving out of the realm of engineers and geeks only to a diverse community including people without backgrounds in engineering and design.