Thread: Smaller Diameter Wheels - What's the advantage?
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Unread 05-04-2010, 21:30
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Re: Smaller Diameter Wheels - What's the advantage?
There are many things that are the same or can be made the same (like speed or torque -- this can be made the same using ratio) with small wheels but others cannot be so easily made the same.

There are two that come to mind.

1) the radius that hits the floor is one difference that is mostly a negative (even with "rigid" wheels there is some deflection and the smaller the radius the smaller the patch on the ground -- generally speaking)

2) smaller tires are ... smaller. That matters in several ways. It means you can put contact point closer to the frame perimeter. It means that the wheels can be below something that a larger wheel would hit. It means that there is the potential for less weight. etc.

The best engineers I know (in FIRST or out of it) are not dogmatic about things like this. In some cases smaller is better in others larger is better. What "better" means varies from game to game and from robot to robot.

Joe J.
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Last edited by Joe Johnson : 05-04-2010 at 21:42.