I stopped reading the thread at page, two it's nearing bed time for me. But I found the solution for those having a hard time
TURNING IN PLACE with Skid Steer. Turning in place in difficult enough, but remember the
TRAILOR. Not only do you have to pull the wheels sideways, but you have to pull the skid sideways. Trick for the drivers would be to drive forward and then turn. Initiate a drift and then use that to slide. The turns would be wider, but more controlled. It would take practice though.
Example of what I mean:
http://www.youtube.com/watch?v=P5aWAW2hea4
But another proble I see happening is a few teams that have no practice or experience driving with no traction will go straight forward and before even attempting to stop, they will try to stop and either lock of the wheels or put them in reverse. You will stop like this at some point, but I find it likely that the robot will veer off to one side. These are things I've experienced in trying to drift RWD RC cars with PVC Tires. It's different with Skid Steer, but the lack of traction idea is similar.
Quote:
Originally Posted by sdcantrell56
Adding more wheels does not increase traction. The maximum force you can apply to the floor is determined by the coefficient of friction and the normal force. Surface area has no influence.
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Are you sure?
I'm more involved in 1:1 cars and racing, and the general idea is that wider tire = more traction. Same reasoning behind the Bugatti Veyron's 16" wide rear tires.
But to me it would seem that having two/three wheels directly next to each other would make turning more difficult, as the mu is greater sideways than forward. And this is from my observed experience in the FLL....
Another thing I noticed today is that the Rover Wheels aren't true. What I mean by this is that they're completely uneven all the way around. Try rolling one forward, it will fall over to one side real quick. I'm sure mounting them normally and giving them a good once over on a good surface (concrete?) will level it out nice, and prove more surface area. But acording to the guy in quotes, this would be useless?
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Me and my AP Physics teacher had brief discussion on using fans or duct fans (I would prefer the later for a few other reasons) to aid in propulsion. You could possibly add another 10N for acceleration, but you also forget you can
possibly use this to steer the robot. Mount a few small duct fans here and there that generate say 3N each, and you can help correct a drift or even slow down in a straight line....