Flight experiences with DLR-TUBSAT

DLR-TUBSAT is a microsatellite joint project of the Institute of Aeronautics and Astronautics at the Technical University of Berlin (TUB) and the German Aerospace Center (DLR). It was launched on 26 March 1999 with the Indian Polar Spacecraft Launch Vehicle (PSLV) as a secondary payload. DLR-TUBSAT was designed for interactive Earth observation where the target is not identified in advance; a search action is involved or a target has to be visually followed. Whereas classical Earth observation uses nadir pointing satellites, the design of DLR-TUBSAT was made for using interactive control strategies. Since the start of the operation many different strategies for different acquisition and operation modes have been developed and tested. A result of this development is new software programs on satellite and ground segment and new ground control procedures. Possible applications of the produced Earth observation data could be defined and were integrated into the new control strategies. DLR-TUBSAT showed that it can serve new market areas of Earth observation and new customers, which can not use or do not want to use classical Earth observation satellites. The main advantages are the interactive search abilities, very high repeat cycles (1 day) and the low mass and low costs of the satellite system.