Miniature Light Tracking BEAM Robot
In the late '90s and early 2000s, tinkers started developing “BEAM” robots. The actual definition of this is apparently debatable, but roughly stands for Biology Electronics Aesthetics and Mechanics, and the idea is to make robots that use basic elements in a clever manner to build basic intelligent robots.
Jack Spiggle (AKA NanoRobotGeek) decided to create such a ‘bot, which is solar-powered using a new IXOLAR monocrystalline solar panel. These panels produce a staggering 25% efficiency, and can even work indoors or in partial shade. So while the idea of a a light tracking BEAM photovore isn't new, Spiggle thought he could assemble one that’s better than what has come before with this tech.
His build, in keeping with the BEAM theme, doesn’t incorporate an Arduino or µC, but instead tracks light with a pair of transistors, voltage monitors, and photodiodes. When the device’s 2200µF energy storage capacitor is charged up to roughly 2.3 volts, the appropriate motor is then be activated by a photodiode, causing the ‘bot to make a small move toward the light. In turn, it’s theoretically “fed” more light as it moves closer to the light source, and starts the charging cycle over for another lurch forward.
The robot’s circuit is designed in freeform style, and the result is quite tiny and pleasing. The construction process is laid out here if you’d like one of your own.