As you can see, the walker has a shell that moves around a round inner piece in a oval fassion. To see a more detailed discription of how this works, have a look at this link. This bot was not built by me, but it explains the walking method rather well. Anyway, the two pieces (circle and shell) need to have the same area, so it has equal traction when it is up as down (the importantce of this is evedent if you have ever seen two of these things push each other around (I built a similer bot using the lego mindstorms NXT system a while ago to vs against my friend in sumo, his robot had rubber on the shell, but not in the middle, and he lost ground every time his shell lifted in the air.)) So a little math (and help from a math teacher) later, and I figured out the required diamiter of the circle, and drew a scale drawing:
The bot will have almost ( the walking method requires some blank space, as evedenced by the drawing ) half of the possible area on the ground at any time, and sometimes all of it, which, if covered with an approate high-traction material will give a ridculas amount of grip.
The centre circle will be driven by a gearmotor in order to turn the bot, it does not need to be overly powerful, but fast enough to spin the bot at a good enough rate to not let it get ambushed from behind. The walking mechanisim will be driven by a cam system much the same as "clunkers" but with a much smaller cam, the bot does not need to take big steps, nor go fast when pushing, and will be able to get by with a less torquey motor.
At the begining of the match, the front plate will fold down giving the bot a nice low profile wedge front, and will also be hinged as in the picture so that if a robot hits the side of my bot instead of dead on the walker will still possibly be able to get under by continuing to rotate. As for opponent detection, just about any method will work, be it mechanical, optical, or sonic.
I know, crazy, but I think it might work.....