[Gary Dillard]

Originally Posted by JamesCH95

Polymers as traction surfaces generally lose traction efficiency as normal force is increased. Search CD or any tire test data if you don't believe me. I would anticipate some specific traction (tractive force per unit weight) loss as you add on weight. You will have more total tractive force, but relatively more mass to move.

While that may be true for "frictional traction", it's not necessarily true on carpet where a considerable amount of the tractive force is actually a normal force between projections on the wheels and fibers on the carpet. The reason brekoflex type belting and some mechanums get such good traction is the amount of embedded overlap when edges on the wheel surface dig down into the carpet, which is a function of weight but more importantly an inverse function of contact area. Our previous testing and data has shown this.