DIY – Arduino Based Solar Tracker

Art emulates nature or nature emulates art? This arduino based solar tracker would be considered a result of craft and knowledge, but it emulates nature and art beautifully. Like a sunflower, the arm in this project looks out for and tracks the sun, or the most radiant light source in an arena. It is a lovely DIY that is cheap, fun, and can be installed on your rooftop or window with good effect.

Geo Bruce, an instructable user, made a sensor of 4 LDRs with sheets between them. As can be seen in the image, the white strips are the LDRs . When the arm is pointed to the light source, the four LDRs receive the same amount of light on them. So, say, if the sun is on top-left position w.r.t. the arm, the top-left sensor gets most light and the right-top, the right-down and the left-down sensors are in the shadow.

Using this difference, a code is written on arduino to figure out the most radiant light source and then instruct the motor to point the attached arm in that direction. Simple and effective.