[sanddrag]

I've seen a lot of people bring up the point of robustness in shifting transmissions. The thing is, just because it shifts doesn't necessarily mean it is less robust or less reliable. For us and many other teams, we have made a shifting transmission that has had no failures over the course of the competition and demonstration. We design things to work properly and not break, and I hope everyone else does to. And the end result is they work properly, and they don't break. As long as this step in the design process is taken, anything can be robust enough to not fail. There are plensty of single speed gearboxes out there that have had serious issues, and plenty that haven't. It all depends on the design and the quality of fabrication. Making a gearbox shift does not at all preclude that you will have problems with it's robustness or reliability.

Also, this issue of size and weight has been brought up. A shifting transmission will almost never be smaller or lighter than a comparable single speed, but the difference can be made very small. Also, say your transmissions come out to be a few pounds more. Now, would you really want those extra pounds out at the end of an arm, or don't you think they'd be better nice and low in the base. If you make one thing lighter, you are going to make another thing heavier since the total weight is almost always a constant. So, it is a matter of exactly where you want those pounds to be. And I vote for them to be nice and low in the base.