@inproceedings{DachwaldWurm2009,
  author    = {Dachwald, Bernd and Wurm, P.},
  title     = {Design concept and modeling of an advanced solar photon thruster},
  series = {Advances in the Astronautical Sciences},
  booktitle = {Advances in the Astronautical Sciences},
  publisher = {American Astronautical Society},
  address   = {San Diego, Calif.},
  isbn      = {978-087703554-1},
  issn      = {00653438},
  pages     = {723 -- 740},
  year      = {2009},
  abstract  = {The so-called "compound solar sail", also known as "Solar Photon Thruster" (SPT), holds the potential of providing significant performance advantages over the flat solar sail. Previous SPT design concepts, however, do not consider shadowing effects and multiple reflections of highly concentrated solar radiation that would inevitably destroy the gossamer sail film. In this paper, we propose a novel advanced SPT (ASPT) design concept that does not suffer from these oversimplifications. We present the equations that describe the thrust force acting on such a sail system and compare its performance with respect to the conventional flat solar sail.},
  language  = {en}
}
@inproceedings{DachwaldWurm2009,
  author    = {Dachwald, Bernd and Wurm, P.},
  title     = {Mission analysis for an advanced solar photon thruster},
  series = {60th International Astronautical Congress 2009, IAC 2009},
  volume    = {Vol. 8},
  booktitle = {60th International Astronautical Congress 2009, IAC 2009},
  publisher = {Elsevier},
  address   = {Amsterdam},
  isbn      = {978-161567908-9},
  pages     = {6838 -- 6851},
  year      = {2009},
  abstract  = {The so-called "compound solar sail", also known as "Solar Photon Thruster" (SPT), is a solar sail design concept, for which the two basic functions of the solar sail, namely light collection and thrust direction, are uncoupled. In this paper, we introduce a novel SPT concept, termed the Advanced Solar Photon Thruster (ASPT). This model does not suffer from the simplified assumptions that have been made for the analysis of compound solar sails in previous studies. We present the equations that describe the force, which acts on the ASPT. After a detailed design analysis, the performance of the ASPT with respect to the conventional flat solar sail (FSS) is investigated for three interplanetary mission scenarios: An Earth-Venus rendezvous, where the solar sail has to spiral towards the Sun, an Earth-Mars rendezvous, where the solar sail has to spiral away from the Sun, and an Earth-NEA rendezvous (to near-Earth asteroid 1996FG3), where a large orbital eccentricity change is required. The investigated solar sails have realistic near-term characteristic accelerations between 0.1 and 0.2mm/s2. Our results show that a SPT is not superior to the flat solar sail unless very idealistic assumptions are made.},
  language  = {en}
}