[Jimmy Cao]

All the mouse really consists of are two encoders, one along x, one along y. Wire both of them (to dig IO, set to in) and then set up an interrupt to count their ticks. Figure out how many ticks/inch or ticks/foot or there are (drive the robot 10 feet, and have the robot printf the ticks).

Then use that data to tell the robot to go n ticks. If you only want to travel along x, then use the y axis as "error", and if the robot picks up travel along y, have it autocorrect.

Did that make sense?