No Batteries Required !!!
This Photovore Robot is a capable little robot that is powered entirely by solar energy, has light-sensing directional optics (eyes), and a pair of obstacle avoidance sensors. The pair of infrared detectors on the robot give it a very directed phototropic or light-seeking behavior, making it trace outlines around shadows, and be attracted to the brightest sources of light.
The SolarBug Photovore 5.0 uses new "MillerEngine" technology to make a very dynamic light-seeking & obstacle-avoiding robot. All components necessary for the Photopopper are in the kit, including a high-quality printed circuit board, optics and motors.
The Miller solar engine uses a 1381 voltage detector (a.k.a., a voltage supervisor) IC to drive a voltage-based solar engine. The 1381 is normally used to reset CPUs and Micros when the power supply drops too low for reliable operation. So 1381s detect and switch when the input voltage crosses the rated upper and lower thresholdvoltages. The upper- and lower-switching voltages are slightly overlapped so that the turn-on voltage is a few hundred mV above the turn-off voltage. This hysteresis keeps input noise (around the switching threshold) from resulting in multiple output cycles as the transition occurs.
The Miller SE is designed to increase the 1381 hysteresis to a larger value. This is done by putting a small capacitor across the input legs of the 1381, and a diode between the 1381 and the "true" ground.
Circuit Diagram of Miller Engine