[EricH]

Originally Posted by s_forbes

In addition, it helps if the robots center of gravity is directly over the middle wheels (or as close as possible).

Yes and no. Granted, it'll turn better. It'll also rock better. Having it on one end will simply shorten the wheelbase and you'll turn on four wheels. Take a look at 330 in 2005 and 2007. The CG was aft, and they still turned well.