[Interactive Devices] Device of the Week II – The Third Thumb

The Third Thumb Project
By Dani Clode

The 3D-printed thumb prosthetic, created by product designer Dani Clode, is capable of carrying out an impressive range of motions designed to extend the wearer’s abilities. It is easily attached to the hand and is controlled by the feet. Through this project, Clode wanted to demonstrate how human body responds to wearable prosthetic technology.

How It Works?

The flexible thumb has two joints which is attached to a wristband. Two servos located in the wristband receive bluetooth signals from pressure sensors in the user’s shoes. The thumb’s 3D parts are connected using a Bowden cable system, similar to a bike brake.

Once the pressure sensors are pressed down with one foot, the thumb gets the signals and makes a grasping movement. Lift up the foot to let go of the pressure, and the extra thumb returns to its normal position.

“..when we reframe prosthetics as extensions, then we start to shift the focus from ‘fixing’ disability, to extending ability.” – Dani Clode

The Pros

The Third Thumb allows for a variety of designs and customisations for different types of people. It can actually be a positive body image statement and symbolise someone’s personality. The mechanism of the whole device is very straightforward that it should not be difficult to fix should there by any damages or errors. The learning curve is also rather minimal and people are able to get used to the controls quickly.

3D printing used as a medium enables quick prototyping, customized designs for various hand sizes and one-off production.

The Cons
The concept of ‘prosthetic’ is meant to be an “addition to”. Over time, this idea of prosthetic seems to have morphed into being a way to fix a broken body. This product should just be an extra part to use as a tool and not to replace a missing or broken body part.

Control-wise, it should be tiring after lifting and putting down our foot multiple times just to grab something. One needs to be able to focus and multi-task while having the thumb on them.

An Alternative Application
The goal for The Third Thumb is to provoke society to consider human extension created in an approachable design. This extended thumb could be a widespread social engagement – from a jewelry designer, to a falcon handler to a tattoo artist to a toddler. Almost everyone are able to experience this piece of device.



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Believes in creating works that someone can not only see or touch but be part of, to be within them.

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