Alright, so here's my design.
The chassis is an old Logitec DS case. It's fairly large, about 8 by 4 by 1.5 in. It has a fliptop that can open up and allow easy acces to the things inside. Holes will be drilled through the top, front, and sides for sensors, switches, buttons, lights, servos and other things to poke out of. All of these are going to be connected to the circuit made on a breadboard. The main part of the servos will also be housed inside, allowing only the rotating part to stick out. There will be two servos and a PVC pipe cut in half for a castor. I have a broken leg right now, so I really don't have access to a computer most of the day, so I'll see if I can upload a picture.