A couple of BEAM robots
For anyone unfamiliar with the acronym, BEAM stands for Biology, Electronics, Aesthetics, and Mechanics. The idea behind these robots is to use the fewest number of parts possible while achieving the greatest functionality. This is a picture of two BEAM robots I’ve built within the last few years as weekend projects.
The one on the left is known as a “Photovore” due to it’s tendency to move toward the brightest light source. It uses two circuits called a “solar engines” to charge the capacitor on the back using the solar panel, and then discharge it into a motor once it reaches a certain voltage level. The motor chosen depends on which of the phototransistor “eyes” on the front is receiving more light. It is based on the Photopopper from solarbotics, and uses this circuit from the photopopper PDF:
The one on the right is a flasher. It simply discharges it’s capacitor into the two LED “eyes” on the front repeatedly, causing it to flash at different rates depending on the brightness in the room. It uses the solar engine below, found at BEAM Online: