This invention is a trough solar collector that uses inexpensive aluminized plastic films as the reflecting surface. The system comprises a rasping head which may be low profile and offer a flat cuttingrasping surface, and is configured to be driven by an attached hub that translates a rotational movement into a reciprocating motion. Data providing directions for traveling from said first location to said second location is collected. The second signal generation section generates an ONOFF control signal and a second light amount control signal as a pair of signals from a combination of a density modulation and an area modulation.