Research and development of pulsed plasma thruster systems for nano-satellites at Osaka Institute of Technology

In the Project of Osaka Institute of Technology Electric-Rocket-Engine onboard Small Space Ship (PROITERES), a nano-satellite with electrothermal pulsed plasma thrusters (PPTs) will be launched in the end of 2012, because the launching was delayed due to change of schedule of Indian PSLV launcher. The main mission is powered flight of small/nano satellite by electric thruster. This study aims at improvement in discharge stability by changing detailed configuration of PPT system. As a result, a new PPT head Flight-Model (FM), i.e., a nearly-optimized PPT head with high discharge stability was designed. From endurance tests with the two PPT head FMs connecting the PPU FM, the total impulse of each PPT head reached 5.0 Ns with no miss-firing. Finally, all interfaces among the PPT system, the onboard computer and the satellite electric-power BUS unit were completely accepted. An unsteady numerical simulation was also carried out to investigate physical phenomena in the discharge system including plasma and discharge electric circuit and to predict performance characteristics for electrothermal PPTs. Both the calculated impulse bit and mass shot agreed well with the measured ones. The calculated results of 40,000-shot endurance test agreed with the measured ones. Furthermore, the research and development of the 2nd PROITERES satellite with high-power and large-total-impulse PPT system are also introduced.