Multi-directional (omni) wheels provide motion in the forward and reverse direction and at the same time allow for easy, smooth-rolling sideways motion.

So how does a robot that can move in all directions work? The trick is that it uses special wheels .  The omni-wheel is not actually just a single wheel, but many wheels in one. 

There is the big core wheel, and along the edges there are many additional small wheels that have the axis perpendicular to the axis of the core wheel. The core wheel can rotate around its axis like any normal wheel, but now that there are additional wheels perpendicular to it, the core wheel can also move parallel to it's own axis.

For better understanding of how multi-directional (omni) wheels work, watch this Video first

Specifications

• Outer Diameter:  41 mm 
• Hub Width: 17 mm
• Inner Diameter:  14 mm
• Number of Rollers: 8 
• Can move in any direction
• 360 degree movement and direction

Click here for more information on how multi-directional wheels used in robots

Click here for how to calculate robot wheel diameter