[EgROS]

We have a double roller design which sounds very similar to 1730's as described above.

We also initially had only one roller. We played around with various positions but eventually settled on placing it a little bit above half way between the middle and top of the ball. It worked pretty well but we would lose the ball when we backed up to fast, pivoted on our axis or moved sideways (mecanum drive). We realized that the source of the problem was that the roller, while pulling the ball toward the robot, was also smashing the ball into the ground with considerable force (we put the robot on blocks, put a scale under the ball and measured it to be over 20 pounds!) The amount of friction between the ball and the ground prevented it from staying with us when we moved.

The solution: a double "roller" system to take most of the downward force of the ball off the ground allowing it to stay with us wherever we go. The bottom "roller" is actually just a 1/2 inch square aluminum bar which sits about a 3/4 of an inch off the ground. The bar rides up and down 7 inches on linear bearings so that it can clear the bump. Our kicker/ roller is on the long side of the robot but when we go over the bump we turn 90 degrees so that the short side is facing forward.

I can’t wait till next week to try it out in competition!