The video at this site demonstrated how to get a robot to follow a line using a single sensor. You have likely seen that this method of following a line has several limitations. Certainly you could enhance your programming to use different strategies to improve how well the robot follows the line with a single sensor, but you might also want to consider adding a second light sensor.
Following are pages at other sites with ideas on how to improve your line follower:
One and two sensor line following
http://www.geocities.com/laosoh/robots/linefollow.htm
"Toeing the Line" - a report by a 9th grader on multiple line following techniques
http://www.fll-freak.com/misc/01-jgray_report.pdf
More advanced strategies with one light sensor and an NXT
http://home.earthlink.net/~xaos69/NXT/Line_Follower/Line_Follower.html
AND, you can use three sensors - so what would you do differently if you were using THREE light sensors???
