| These are treads. Treads are an alternative to wheels for a mobile robot. Because there is a lot more surface area in contact with the ground, treads provide much more traction than wheels with tires. |
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The hubs that are used with the Lego treads spin freely on an axle. In order to lock them to an axle, you must insert a gear inside the hub. |
You should use treads when you are building a slow but strong robot. The threads will give you much more friction with the ground and will let the robot push harder.
