Irregular Drivetrain

[zachrobo1]

So this year, my team is working on a 6wd drop center drivetrain. While working on it, we realized that the belts we had were not long enough to make the distance from the back wheels to center wheels and front wheels to center wheels the same. It is probably around 6 inches of difference. So, our question is this: How big of a deal is this difference in regard to turning?

[Lil' Lavery]

Are you going to move your outer wheels towards center to allow the belts to fit, are you going to run your outer wheels without any power? What are the dimensions of your drive base? Have you considered ordering longer belts? Running chain instead of belts?

[zachrobo1]

We do want all wheels to be powered, so the back wheels are moved outwards a bit. We are using a modified (30" long 21" wide) 2013 Kitbot Chassis (Don't worry, nothing was built before Kickoff). We are considering using longer belts/chain, but were going to figure out if it made a difference before we placed an order.

[Anupam Goli]

What are the dimensions of your turning base? The only issue that presents itself with shortening the wheel base but keeping the same drop is that an 1/8" drop with a shorter wheel base is some unwanted rocking in the base. How much distance is there between the middle wheel and both outer wheels, and how wide is the distance between the two middle wheels? More than likely you should be fine with a 1/8" drop. You can also mitigate any rocking issue with clever weight distribution and CG manipulation.

One thing you may want to look into is instead of dropping the center wheel 1/8" of an inch, try raising the wheels that are farther out by 1/8", and set the weight distribution such that the CG is on the wheels that are touching the ground at all times.

[ErvinI]

You can use a combination of weight distribution and the irregular drivetrain to make your robot turn quicker/slower depending on what your goal would be.

So no, it just means that your turning will be a bit different.

EDIT: With given information.