Today, programming got the robot for another half hour. In this time, we managed to tune both PID controllers (low and high gear). With this robot, we found that just a P controller works best, and has the least oscillations. In addition, we tested driving over the barrier - with resounding success (see video after the break).
The PID controller is based off of the robot's velocity. What does this mean? Holding the joystick at a constant position means constant movement - adapting to any changes in terrain. This allows for much easier driving, especially with obstacles. We are hoping to get the manipulator soon to test our code.