A mechanical prosthetic arm born out of rejection – Meet Ian Davis

Like many people interested in robotics, DIY, engineering, and just making epic stuff, we love Ian Davis’ YouTube channel. We could not wait to host Ian and have a chance to see his mechanical prosthetic arm when he said he was coming to the UK for a bit of a maker / engineering tour.

Ian has a larger than life personality, he is super warm, funny, generous, and brave! For those of you who know the Bristol area in England you will be familiar with the famous party hostel, Blue Moon, which is where Ian arrived from yesterday morning after an interesting night.
 

Ian’s story is as incredible as it is ingenious. In 2018 Ian was undergoing some extremely intense treatments to fight cancer. The treatments targeted the cancer but also compromised his immune system. With his immune system compromised, Ian had to undergo a surgery to repair his broken hand after an accident. The surgery resulted in multiple infections which developed into sepsis. Ian then had to undergo his first finger amputation in a bid to stop the infection from spreading. He thought he was winning the fight but at every check-in came the news that another finger had to be removed until he had amputated all four on his left side. 

While in hospital and recovering from surgery his family brought him his Makerbot 3D Printer, and that’s where his personal journey with prosthetics began. He started designing in his hospital bed, and was soon printing ABS parts and prototypes on the Makerbot in his room. This was not super difficult for Ian because as luck would have it, Ian had experience building prosthetics at college. 

‘Fingers are a luxury – have a nice day’

Ian applied to his insurance company for funding to cover a partial hand prosthesis. “My application was denied with one letter stating that fingers were considered a luxury and therefore not necessary.” recalled Ian. 

He proceeded to appeal the decision three times and eventually won his insurance fight (we’re impressed with his sustained advocacy and while not ok, this is the reality of what a patient will need to do if they receive a denial from their insurance). 

Having won his lengthy battle with insurance Ian was super excited to head to Ohio to pick up his new powered digits.

However the excitement was short lived.

The chicken accident and an epiphany 

With his fingers newly fitted Ian headed back through the airport to catch his flight home to Oregon. His flight was called right after he had picked up some tasty orange chicken. With his tickets in his human hand and his chicken grasped by his robotic digits he quickly headed to his gate when his fingers lost power and opened his fingers. Ian watched in horror as his chicken flew across the airport. 

This was embarrassing and devastating for Ian who realized that these new bionic fingers may actually not be the best option for him. 

While a disappointment, it did provide a spark that would go on to ignite a project that has won him fans all over the world (over half a million on YT!! Go Ian!). It was then and there that Ian decided partial hand prosthetics, for him, had to be 100% reliable. They needed to be battery and power free. No sensors. No motors. Just strong, reliable, mechanical engineering.

These are some of the tenets Ian abides by religiously when it comes to his mechanical prosthetic arm design, and it produces great results. 

Ian admits that the powered digits have their place, as do other designs available that cater to different lifestyles and activity needs. However, there was nothing available at all for people like Ian. 

Ian runs a heavy machinery workshop. He spends all day heavy lifting in an industrial setting working with expensive equipment and tooling on projects that require precision. Ian needed a design that could handle lifting 400lbs, that could deal with fine particles, dirt, heat, and water, while being robust against the knocks of the job. Ian believes that his mechanical arm design is the only design available that caters to people who are really going for it in an industrial setting like a factory, metal workshop, or farm.

The learning curve

But even the ingenuity of the design cannot solve for the potential apathy of the user. Ian says that he can build you a mechanical prosthetic arm that can handle a load of 400lbs, but can your body lift that weight? He says people forget that the device spec potential is only fulfilled by the person who wears it. It is attached to your human body, can your human body lift that weight? Do you have the bicep, chest, and shoulders? Is your socket fitting well enough to transfer the loads? Some people forget that the body needs to do the work, and without a well-fitted socket, you won’t be able to make the most of the prosthesis. 

The other challenge Ian sees a lot is people with limb differences who want a device that they can operate smoothly and intuitively but they don’t want to practice with the device. “Mastering any device means failing a lot. It means approaching the same object over and over until you know exactly when to trigger your sensors or when to start activating your fingers. You need to practice different grips on different objects at different speeds so you work out which methods are most effective for you. You have to be ok with dropping a lot of objects if you want a bionic hand or a mechanical hand to feel fully embodied and operate like second nature.”

The Kit

Ian is working on developing 10 kits for 10 participants to DIY their own mechanical prosthetic arms based on his ideas. He hopes this kit will make life easier for people missing fingers looking for a solution outside of insurance battles and the medical device industry. This is not a medical device. This is a maker device.  

Is the Hero Gauntlet for Ian? 

We laughed with Ian at the idea of him using the Hero Gauntlet to lift 400lbs of metal. Ian pointed out that the Hero Gauntlet is not made for him, it is for lightweight activities, lifestyles that are outside of the rugged terrain of his workshop. We were happy with this summary. Ian is not the user demographic we worked with in developing the Hero Gauntlet. It’s a tool used for carrying shopping, pulling your suitcase, and handling two objects at the same time, like enjoying fried chicken while holding plane tickets. We prioritized making it as simple and lightweight as possible so it’s comfortable for a range of users to wear all day. Ian’s work is specialized and we’re excited to see the first 10 – 20 people benefit from it!