US Navy reinvents the wheel

As if following the adage “everything can be improved”, the US navy has reinvented the humble wheel.

It looks like any other wheel from outside. But the similarities end right there.

This wheel is so different from its long standing predecessor, that the patent actually describes it as a fully sufficient propulsion system.

While a regular wheel is driven from an external force such as a rotating axle, this patented wheel is driven internally.

But that’s not all, it does not use any mechanically moving parts like gears that are subject to wear.

So how does it work?


Inside the wheel, electromagnets are arranged around the periphery while a magnetic fluid is situated in the central region. When these electromagnets are selectively turned-on, the magnetic fluid gets attracted and moves towards those electromagnets. As a result, the center of gravity of the wheel shifts causing the wheel to rotate. By controlling the sequence of activating these electromagnets, a sustained rotation can be imparted to this wheel in any direction. So not only is this a self-propelling wheel, but also an omni-directional wheel.

While this could in principle replace wheels everywhere, for now the US navy intends to use them for Robots.

Patent Information
Publication number: US 9,390,847
Patent Title: System and method for electromagnetic-based propulsion
Publication date: Jul 12, 2016
Filing date: Feb 19, 2015
Inventors: Nghia X. Tran; Hoa V. Phan; Anhtuan T. Ton;
Original Assignee: The United States of America as represented by the Secretary of the Navy