we have built a prototype for the past 5 - 6 years.
we first build prototype parts and small systems, then get them sorted.
then we build a prototype robot, based on the emerging design we are creating. we build it with the intent to be funcationally equal, but it is often heavier and uglier than the competition robot. it has extra holes, used parts, etc. After it is built and tested, we then finalize the design and buid the competition version.
we have learned to go back and rework the prototype to make it work like the competiton robot where it is needed, otherwise there can be subtle differences that can cause great pains.
it also makes building the competition robot faster and it is more durable because it only has to be assembled once, since all (most
) of the lessons are learned on the prototype.