Mecanum wheels, also known as Ilon wheels for their inventor Bengt Erland Ilon, are wheels designed to move a vehicle in any direction. Japanese pro LEGO builder Yoshihito Isogawa has been building vehicles with different configurations of mecanum wheels, like the epic LEGO Mindstorms Mecanum Rings vehicle above. Watch the video to see how different wheel combinations on his remote control change the vehicle’s direction.
A bit more about the engineering from Wikipedia:
It is a conventional wheel with a series of rollers attached to its circumference. These rollers typically each have an axis of rotation at 45° to the plane of the wheel and at 45° to a line through the centre of the roller parallel to the axis of rotation of the wheel…
Moving all four wheels in the same direction causes forward or backward movement, running the wheels on one side in the opposite direction to those on the other side causes rotation of the vehicle, and running the wheels on one diagonal in the opposite direction to those on the other diagonal causes sideways movement. Combinations of these wheel motions allow for vehicle motion in any direction with any vehicle rotation (including no rotation at all).
For other examples, see Isogawa’s LEGO Mindstorms EV3 Mecanum Car:
And his LEGO Mindstorms EV3 Mecanum Crawler, too: