The full squeak file can be downloaded here.
Here is the Rover by itself. Squeak identifies interactions with objects based on color...thus the multicolored variety of the model. "Depth" of vision would have been taken care of by the long lines, representing the field of view of the IR sensors, but we didn't get as far as obstacle avoidance with this model. The red and green circles are representative of the 4 LTV sensors we use to detect path boundaries.
Here is the rover scaled down and inserted into a project. This was the only path orientation we were able to test. You can also see the script code used to follow the paths here.