Quote:
Originally posted by Kevin Ray
It seems to me that many teams who have successfully run in the past with belts have this year opted for wheels. Can any of you that fall into this category give me any ideas why?
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The problem with belt is that it can have a very high coefficient of friction. Most teams are going for high-speed, low torque robots this year. They wouldn't have enough torque to turn the robot without tripping breakers. Either that or you'd see a lot of drill motors frying. Not to mention most teams aren't very experienced in using treads. Without all the proper safety mechanisms in place, they are prone to fall off or rip.
Belt isn't always a good thing. The amount of traction your robot will have depends on three things, the traction material, surface area, and robot weight.
The type of traction material comes into play because if you look at the carpet, it's made up of many, many strands called fibers. These fibers need somewhere to go. If you have deep grooves in your wheels/treads, the fibers will go there. The edge of the tire treads are what actually give much of the traction.
Surface area does come into play becaus you get traction when the carpet fibers interlock with the treads on your belt/wheels. The more surface area, the more weight for every square inch of traction material touching the ground. If you put enough weight, you'll squish the carpet fibers entirely, and there won't be anything for the wheels/treads to grab onto.
In normal physics, surface area is not a factor when calculating friction. However, when surfaces have the ability to deform, surface area (more importantly, pressure) does come into play. Moving something accross a hard floor versus the carpet is different.