Victor, In your video the robit moved around a fair amount, did you program it with a specific set of instructions of were you typing the directions off to the side? When I built mine i did everything throught he serial monitor. But if seems like...

Something that i did whilst playing around was add the buzzer to the robot and had it go off anytime the robot reversed in direction. I also add elastic bands to the wheels to provide more traction. This also created it's own problems with...