Invented in 1981, the Walking Gyroscope is a cool toy that uses centrifugal force to move. Here’s an open source 3D printable version.

Join us on a journey through the misty ruins of time. To the ancient past where Ronald Reagan was President, Michael Jackson was about to become King, and dinosaurs roamed the Earth (possibly). The year is “1981”.

Robotics Engineer John Jameson has invented a tiny gyroscope with feet, which uses a metal flywheel and pivoting legs to create forward motion. The design for the walking toy wins plaudits, and is a big seller in Japan, where it’s licensed by Tonka for their GoBot line of transforming robot toys.

In the US, the same design was patented by toy giant Mattel. But lo! Tragedy strikes when the company decides to shelve plans for mass-production. American childhoods were deprived of the joy and delight that comes from seeing a wobbly walking gyroscope. They make do with ‘Masters of the Universe’ and ‘My Little Pony’ instead.

Snap! Back to the present day. More than 30 years later — and with the patent now expired — John’s good friend Jeffrey Kerr has modified the design for 3D printing. The result is a fully open-source 3D printed toy design, downloadable (and remixable) from Thingiverse. A step-by-step tutorial is available on Instructables.

Gyroscope Uses 104 Pennies for Balance

The modification of the design takes one ingenious, delightful turn. Where the average person wouldn’t have access to a perfectly balanced metal disc to use as a flywheel, this version uses a plastic flywheel weighed down with 104 pennies as substitute.

The heft of the pennies, in tandem with the magic and mystery of centrifugal forces, is what allows the tiny toy to veer from side to side and walk all by itself. Think of it as a piggy bank with legs.

As Kerr further explains on the instructables page:

But what if you don’t live in the United States, or don’t have US currency in your pockets? The Thingiverse community has remixed the design to account for other sizes of coin. Ranging from Taiwanise dollars to UK pennies, this is open source design in action.

And what about the original designer, John Jameson? Rumours are circulating that he’s assembling a giant gyrobot to take revenge on Mattel and conquer the Earth. From small acorns, spring mighty (gyroscopic) oaks.