#332 | Project ITO

Project ITO is a DIY adjustable arm prosthetic for bowing the violin with only the shoulder movement. Inspired by and named after Manami Ito, the one armed violinist.

Its length is adjustable for growing children. A kid as young as 3yo can start to learn violin and continue past adulthood without ever needing to replace it.

A DIY project with limited ready-made parts that anybody could afford; Building it by hand or by using other publicly available technologies such as 3d printing & laser cutting.

For the plans and the original open source page, please use this link.

Disclaimer

Project ITO is specifically designed for bowing the violin in mind and it’s function and will be described as such; However, this does not change the fact that it can be used for any other application as the user sees fit.

I’ve personally used the earlier prototypes as a third arm for holding a magnifying glass & flashlight, go wild!

Item #332 is consisted by 6 elements:

-Shoulder “Tendon”

_This is the part where the regulating wire anchors itself, the left shoulder.

-Shoulder Mount

_Is the point where the user can manually lock the position of the 360° prosthetic shoulder angle (similar to setting up a tripod with a setscrew)

-Forearm Drive Anchor

_Is a two sided setscrew lets the user adjusting both the cable length and the distance from the elbow pivot. This greatly reduces the strain on the shoulder use while giving the option for fine tuning.

-Wrist Rail

_It is a J shaped hard wire lets a violin bow mounting adapter freely slide by the range of a human wrist. Combined use of gravity and the elbow/shoulder positioning creates the requires bowing motion and angle

-Bonus: Alignment Rod Clamp

_The violin certainly requires a fixed vertical rod to prevent the bow going astray. (I’ve seen cheap net holders for table tennis tables of all things can provide an easy ready-made piece for it, modifying a cheap C-clamp with a rod could easily give simillar results)

On my second year in NABA, in FAB Lab class, we were assigned to replicate someone else’s DIY project or make one if it doesn’t exists.

At that time I’ve seen the viral videos of Manami Ito with her custom prosthetic arm bowing the violin. I wanted to replicate the prosthetic and possibly more.

I couldn’t find proper close up shots of the said viral video and my attempts to contact with Manami Ito herself was unsuccessful but I was dedicated to build it no matter what.

I was also thinking about what size to build it since, as many of you guessed, people comes in different shapes and sizes; Then it occurred to me to make it adjustable and even better, finding the earliest age to learn the instrument and making the minimum size compatible with the age group, making the entire prosthesis a one-time, life-long investment.

The design process was a grueling one, just because the year was 2020 and I was stuck with only small needle-files rather than my usual tools, I’d kill for a rasp. Shaping those prototypes took literal weeks of sleepless hand grinding instead of being done hours, regardless of how simple they looked.

Every iteration felt high stakes. But I wanted to make it easy to make, cheap to buy and intuitive to use; I’ve made 3 complete redesigns total, which only the final prototype survived as I achieved my goals. It still works to this day.

This was my first introduction to bowden cables and truly mechanism oriented designs, I’ve never stopped since and I probably wouldn’t be making #338 as my thesis the very next year.