Industrial Electronics

Video: Could You Use a Third Thumb?

07 July 2017

The Third Thumb could be used as a natural extension of the human body or for disabled people. Image credit: Danielle ClodeThe Third Thumb could be used as a natural extension of the human body or for disabled people. Image credit: Danielle Clode

Think of how often you use your thumb. Unless you really pay attention, it is remarkable how often your thumb is used for everything in life.

Now imagine what you could accomplish with a third thumb. That’s the idea behind The Third Thumb Project, which just recently won the Helen Hamlyn Design Award for Creativity from the Royal College of Art’s annual awards.

The Third Thumb is a prosthetic additional digit that is controlled by the feet allowing the wearer to strengthen and enhance natural dexterity through a combination of robotics and wearable technology. While this is a no-brainer for disabled people, the Third Thumb could also be used as a tool to extend human augmentation or to enhance productivity.

How It Works

The Third Thumb replicates the movements of a human thumb using two motors pulling against the natural tension of flexible 3-D printed material. The motors are controlled by two pressure sensors located in shoes and under the toes that communicate via a Bluetooth connection.

The foot control was inspired by the strong connection between a human’s hands and feet such as driving a car or using a sewing machine or playing a piano.

The Third Thumb consists of a 3-D printed structural cover for the hand and wrist made from formlabs grey resin. The thumb is a live-hinge based design made of 3-D printed 85a shore flexible filament. These parts are connected via a Bowden cable system that is made of Teflon tubing and wire.

Danielle Clode, a New Zealand designer that created the Third Thumb says 3-D printing makes the project essential because it enables quick prototyping and the ability to customize designs for various hand sizes and one-off production.

“By extending the body I see it creating a similar trajectory for prosthetics as glasses or plastic surgery,” Clode said. “Creating a shift from medical device to positive body image statement. Success is widespread social engagement with The Third Thumb, from a jewelry designer, to a falcon handler, to a tattoo artist, to a toddler, the more people who experience it, the better, framing it in different functions and aesthetics.”

To contact the author of this article, email

Powered by CR4, the Engineering Community

Discussion – 0 comments

By posting a comment you confirm that you have read and accept our Posting Rules and Terms of Use.
Engineering Newsletter Signup
Get the Engineering360
Stay up to date on:
Features the top stories, latest news, charts, insights and more on the end-to-end electronics value chain.
Weekly Newsletter
Get news, research, and analysis
on the Electronics industry in your
inbox every week - for FREE
Sign up for our FREE eNewsletter
Find Free Electronics Datasheets