We used to have the fun of getting our robot back to Vancouver, from Toronto, as FedEx would not ship east/west across Canada... only north/south to and from the States.
We were able to book space on a semi-trailer using a Freight Broker. We used
http://lantraxlogistics.com/ but there are no doubt dozens of similar companies in the Seattle or Portland area who would be delighted to help you solve your transportation issues.
You might find similar services described as a "freight forwarder" (
http://en.wikipedia.org/wiki/Freight_forwarder).
In any case, there are thousands of semi-trailers crossing the USA every day. Your robot and pit could be on one.
Heck, now that I think about it, PNW FIRST has had two semis criss-crossing the Pacific Northwest for almost two months. It might be cheapest to have two or three common loading points, and put all the PNW cargo into one big trailer. (Actually... with that many teams going, it might well take two loads...)
Jason
P.S. And if you can get it all organized to ship the robots on a private trailer, maybe there are enough people going to charter a jet.... "Hey, Boeing... any chance we can borrow a few BBJ's for the weekend?"
