How many wheels are you going to use this year

[midway78224]

My team is testing a six to eight wheel drive this year. We are planning on useing only 1 motor on each side and chain them together with a toughbox that came in the kit. We still testing and prototypeing that right now.

We've got 4 wheels on the robot, and 6 spares. I expect them to wear down quite a bit this season...

[Pjohn1959]

Based on the coeffienct of friction, we are using 4 wheels this year. The less points of contact on the new floor, the better.

[midway78224]

We are not sure what we are going with right now. Were still testing. So far we figure out less motors is better but we still testing a four, six, and eight wheel drive

[Matt C]

6wd but only 4 points of contact with the floor at a time.

[qwertyuiop[]\]

3wd with 4 wheels but only 3 on the ground at a time

[Andrew Bates]

Originally Posted by Matt C

6wd but only 4 points of contact with the floor at a time.

So you're dropping the middle wheel?

[ComradeNikolai]

4 for the simplicity it affords; adding wheels would not, by our calculations, provide any benefit, but it does benefit us to have the simplicity of only driving two wheels on each side.

[SpaceOsc]

no 14WD option?

[excel2474]

Originally Posted by Pjohn1959

Based on the coeffienct of friction, we are using 4 wheels this year. The less points of contact on the new floor, the better.

Why is this the case? Is it because there is more wheight on individual wheels?

[GarrettF2395]

Originally Posted by excel2474

Why is this the case? Is it because there is more wheight on individual wheels?

To give you the short answer... yes!

My team is going with a 6WD dropped center wheel for added maneuverability.
We are still playing around with how the wheels will be powered, but as of right now,
they are hooked up via Toughbox with a single motor per side.

[Bob Steele]

Originally Posted by Pjohn1959

Based on the coeffienct of friction, we are using 4 wheels this year. The less points of contact on the new floor, the better.

You get the same traction no matter what number of wheels you use. It is just split between all of them... the total is the same...

In order for this to be true, force has to be able to be applied by all the wheels in contact with the floor. Any non-powered wheels will decrease the amount of force you can apply by lowering the normal force of the powered wheels.

The force you can apply to the floor is contingent in this game simply on the coefficient of friction and the normal force. These two do NOT change when you add more wheels.

In a game with a non-slippery or non-smooth surface I would agree that you MIGHT be able to influence the force you can apply to the floor ( and therefore the acceleration) by adding more wheels or more surface area...but in this game you can only apply the force you are "allowed" to apply by friction.

good luck in your designs!!!

[SuperBK]

On our team, I have voted for 4 wheels, each side driven by a motor. We have another contingent that wanted to have 8 wheels (2 in each corner). I say that won't help traction (for reasons stated above) and will make turning even harder because now you have two wheels locked together so one will have to slip in the direction of rotation during turns. It would be better to have three to a side, since the center wheel would take weight off the outside ones and help the robot to turn, but that complicates the drive train and we are running out of time.
Brian

[MrForbes]

Four, because it's probably not gonna make a difference...the chassis is already built, we have a LOT of work to do to get the ball handling stuff designed, built, programmed, tested and practiced. No time left for chassis this season for us...except for the traction control programming....

[sdcantrell56]

We're going with 6wd with a dropped center wheel on a wide oriented frame for maximum turning. We are also directly driving the center wheels off of a modified toughbox and chaining the outer wheels.