The Rolling Spider is a nice driving base for FLL. It has a spot to mount the medium motor above the brick. The main feature of this robot design is the manner in which the wheels are turned. Since the wheels are not mounted directly to the motors and instead using a gear ratio the wheels spin 3.33 times faster than normal. This allows you to zip around the board to accomplish tasks. Adjust the power accordingly when needing to go slow or make precision turns. The two color sensors on the front allow the robot to line up with lines on the board. Add wires to motors and sensors as you see fit; my recommendation is color sensors to p1 and p2, gyro sensor to p3, ultrasonic to p4, and motors to B and C.
Already have some of the parts? Use the Build this MOC page to only show the parts you are missing.
Waiting for Inventory to load
Use LEGO Digital Designer to open these files and generate step by step building instructions.