It is always amazing how many contestants wind up putting the final touches on their robots the day before the competition. By completing your robot early, you will have time to practice driving and time to work out the numerous glitches and bugs that your robot is sure to have. Many competitors believe that there is a line of corporations just waiting to shower money on them if they declare they are building a robot and looking for sponsorship. It just ain't so. Most of the sponsored competitors have relationships with their sponsors that were formed over time, and usually the result of a business transaction.
Few people are willing to sponsor intent.
So don't rule out that in your first year, you alone will have to pay all of the bills in order to have something to take around and show off for the next year. Other things to consider when looking for sponsorship are your team's reputation, whether you have a website and if so how it can enhance the image of the sponsor, and finally your performance at the event. As this new sport gains visibility the top sponsors are going to have their pick of teams, so you want to work on something that makes yourself stand out. There are as many combinations in use as there are competitors. This is not intended to be an exhaustive resource on radios but here are the basics.