Challenge: Obstacle Course

My Lego Robotics team (yet to be decided) has been presented with the challenge of building a robot that will be able to navigate an obstacle course with several kinds of obstacles; in this challenge our robot will have to use most of the sensors we have been taught to use so far.
The robot must first travel forwards and stop within a boxed out region for five seconds, a light sensor will be used here, after this the robot must ram in to a wall and activate a touch sensor before reversing and turning right. After this the robot will travel forwards and use its ultrasonic sensor to detect a wall, and turn right again. The final leg of the course calls for the robot navigating a randomly placed obstacle; this would probably be done with the use of a ultrasonic sensor and if time allows, some sort of lego 'missile' that will remove the obstacle from the course.

(All of the above while smoking the competitors' robots navigation times of course)

Essentially I am only brainstorming as to the actual design of the robot at the moment...and I'm clueless...so far:

• The robot should be low to the ground - probably longer than taller for balance and aerodynamics :O
• Will need multiple appendage like structures to hold variety of sensors in place and to prevent overlapping of sensors
• May use gear trains to juice all of the possible speed out of the robot (losing torque shouldn't be an issue as it is a flat course)
• The largest Lego wheels possible should be used for additional speed.
• The touch sensor will have to be mounted on the front, as well as the ultrasonic sensor, so some variations in height will be necessary.