[GeeTwo]

We are at about 20 members this year, and are planning to continue doing a practice robot. Even at 10-15, we would continue doing a practice robot (at least partially) assuming we have the budget.

OK, how do you do a practice robot?

Have the same crew (or at least a common set of core members) build the practice robot as the competition robot. This is to ensure that they are as alike as possible.

One of the things which has helped us greatly is using a (modified) kit chassis. If you can build two essentially identical chassis and control systems, and can keep your manipulators down to the withholding allowance weight, you can achieve 80-90% of the benefit of two full robots. Edit: versaframe, or WCP chassis can likely be just as successful, but we've had good results with the AM14U series kits. The key is to be able to build two identical chassis that meet your needs fairly quickly.

When we had many more members, we would switch back and forth between our two robots during the end of build season, and not decide which to bag until very near the end. (In 2015, we switched around noon on bag day!). With fewer members, our top priority for "seconds" is on a drive chassis and control system; we'll be ready to only do a single version of the manipulators. Then, at bag, we can pull the manipulators, put them on the practice chassis, and continue drive practice and development until competition.