[EricH]

I think there are 2 things to be standardized.
1) Minibot activation.
2) Minibot-pole transition device.

#2 is the simplest. The drawbridge or a platform device is simple: move ramp/robot to either the base or the pole and let it do its thing. Telling it when to go could be as simple as a bar across the end that when released turns the minibot on or lets it go.

#1 is harder. NXT device, pure mechanical, non-NXT... Ideally, the start trigger is contained on the minibot and is "running" when the minibot is loaded onto the hostbot.

The 30" height might be tricky--it depends on whether the minibot is allowed to be above the line. But substitute your favorite height in there as you need to.