Here is Simple Electronic Solar Project of Top Robot (1) Make a Robot is not easy, but also not very difficult. Here we start from an easy example – Solar Top. It has below function: Rotator under sunshine Come back if meet Obstacle Keep stay in no sunshine place. This is a simple automatic robot. It don't need people maintance. The life is depend on the environment and mechanical wear. The parts cost is very low. The following is the parts you need: Clip 6 units Mini Motor 1 unit Capacitor 3 units NPN Triode 1 unit PNP Triode 1 unit 2.2K resistance 1 unit LED light 1 unit Some Wire Small Solar Panel ( >4V, 10mA) 1 unit Some Solder Wire Perforated Board 1 unit Below is the robot circuit diagram: