[Al Skierkiewicz]

K,
The VEX line follower uses infra red emitters and detectors. These can be overpowered in the presence of strong IR radiation such as in direct sunlight, or from security cameras close to your test station. They are programmable and to allow you to vary parameters to suit your conditions. Please follow the guidelines and keep the sensors mounted close to the line you are following, 1/8" or 3mm above the line is optimal. In the presence of strong light, it might work better if you shade the sensors so that ambient light is less of an issue.