The Cubli: a cube that can jump up, balance, and 'walk'

Gajamohan Mohanarajah (Gajan) · 15.8M views · 2013-12-17 · 2:37

Open on YouTube ↗

If playback is restricted in your region, try opening the original video. Use Mark watched to add it to your marked videos.

Overview

A demo of the Cubli, a 15 cm cube that uses reaction wheels to jump up onto a corner, balance there and fall in a controlled way to move. The video shows these three abilities chained into locomotion.

On Hacker News

Brought up whenever reaction wheels or self-balancing cubes come up, with the jump-up maneuver singled out as the coolest part.

Recommended by 1 HN people across 1 months · HN mentions 2016–2024

Topics

Robotics Mechanical & precision engineering

What people said

lh7777 · 2024-02 · Recommendation
> I plan to add mechanical brakes to the reaction wheels...This enables jump-up manoeuvers which in turn enable the cube to get to its equilibrium position on its own. Looking forward to this -- I always thought that was the coolest part of the Cubli project. Here's a video: [VIDEO]
Read the original HN comment ↗

jrussino · 2024-02 · Reference
In the old Cubli videos they go further, chaining together "jumping up", balancing, and controlled falling to demonstrate locomotion! [VIDEO]
Read the original HN comment ↗

venning · 2017-07 · Reference
From a related video: the reaction wheels spin up while keeping total angular momentum at zero, then apply a rapid (magnetic) brake to transfer the momentum to the body (from the wheels). I'm assuming if you do that precisely enough (and in three dimensions), you can generate linear movement. EDIT: I'm probably very wrong about the movement. EDIT: The video: [VIDEO]
Read the original HN comment ↗

Sources

Video by Gajamohan Mohanarajah (Gajan), played through YouTube.

HN Library · Source license

Data and selection notes

HN summaries and labels may contain AI errors. HN dates refer to discussions, not video publication.

HN Library: HackerTube export (2026-10-31) and open-index/hacker-news. Upstream summaries and classifications may contain AI errors.

Views, duration and playback status refresh separately from the published catalog. When an update fails, existing data remains visible.

Selection checks

SaaS & AI candidates: Topic keywords do not match
Editor-approved picks: Editorial review is required

Rule matches identify candidates. They do not guarantee video quality or financial results.

About the library and its sources