[dtengineering]

This is our third year. Each year we have used smaller wheels. Our first ones were monster 12" x 2" pneumatics in a 4x4 arrangment. That was done so we could climb up the 6" step.

Last year we used 8" wheels in a 4x4 arrangement with pneumatically actuated caster wheels to help with turning. That was done so we could drive over the bottom edge of the goals if we needed to (as it turned out, it would have been better if we couldn't).

This year we are down to 6"x1.5" wheels in a 6x6 arrangment.... just enough to get up the ramp.

There are many advantages to the smaller wheels, namely reduced weight and size, but also that because the radius is reduced you can put the contact point of the wheel closer to the outside of the robot, thus improving your front/back stability. The bigger wheels are better for climbing over obstacles and for ground clearance. The big wheels from our first year also gave the robot a very rugged "Moon Buggy" type look. Aesthetically it is still my favorite of our three robots, but, well... it didn't really perform all that well.

Next year we are just going to put a few skyhooks on and let it hover.

Jason