Not trying to pick a fight at all. Just bringing in a discussion about a subject which there seems to be much passion.
I have a mechanical engineering degree for starters so I have been through all the proper training/schooling for this discussion.
I also know that racers of any kind, or even car manufactures who make high powered vehicles, always spec their tires to be wide to allow for better traction. Also any type of belt driven sheaves on high powered machines are wide for two main reasons. Strength and the larger the surface area the less likely to slip. The diameter of the sheave has a direct correlation to this as well.
I agree about the responses to the question. The first two are silly.
Since our robots do not do burnouts prior to a match the section about negative static friction coefficeint does not apply. This section also speaks to the type of material being used. In our application this is not a concern as well. We dont leave rubber down the playing field
A couple of things I got from the posted article
Friction is surface-area independent in only a few ideal examples. The real world is more complicated. Especially for tires that are made of rubber
“You want to choose a width, height, and tire compound that gives the best friction for the duration of the race.”
“Increasing tire diameter and tire width increases the contact area.”
It does speak to downward force due to a wing attached yet this does not apply either as we have weight limits and cannot go fast enough in the limited space even if we did have a mechanism to give downward force.
So the only parts of this article which directly apply to us is the width, height, compound and contact area.
I know I could never win a race if I had a skinny tire on my motorcycle.
If even everything else were the same, the burnout, the compound, the track conditions, same powered vehicles. The one with the RIGHT width tire will always win.
Numerous real world examples are before us as to why width, using ruber wheels, does in fact increase traction.
I guess one more way I can put it is this. If you had to move a piece of 4x8 plywood and could not carry it and the only two options you had were to
- Lay it on the ground flat and try to push it?
- Lay it on its edge and push it?
Same amount of weight. one has a bigger contact patch then the other. Which one will be easiet to move?