Chapter 6. Light-Sensitive Navigation with Phototransistors

Light sensors have many applications in robotics and industrial control: finding the edge of a roll of fabric in a textile mill, determining when to activate streetlights at different times of the year, when to take a picture, or when to deliver water to a crop of plants. 

The light sensors in your Robotics Shield Kit respond to visible light, and also to an invisible type of light called infrared.  These sensors can be used in different circuits that the Arduino can monitor to detect variations in light level.  With this information, your sketch can be expanded to make the BOE Shield-Bot navigate by light, such as driving toward a flashlight beam or an open doorway letting light into a dark room.