MAXIM

1
MAXIM

• Propulsion
• Jon Lewis
• Mike Rhee
• 8/19/99

2
Stationkeeping and Pointing Control

• Hydrazine thrusters used as much as possible
• Initial S/C separation DV 0.09 m/s (grams)
• Slew to new target (10º) requires a few kg each
  time (150 times)
• 10º change approximated by making detector S/C
  lag orbit S/C by prescribed distance and in a
  reasonable amount of time
• Finer control will require different propulsion
  device
• Short term acceleration requires constant mN
  thrust, minimal propulsion mass, may be
  accomplished with pulsing of hydrazine, possible
  use ion engine or PPT
• Longer term effects and fine control will utilize
  mN thrusters with good precision, will involve
  creative schemes with flight dynamics and
  attitude control, as well as compromise with
  science

3
Future Considerations

• Separation/Slew fairly well defined and
  understood
• Fine control will require several design
  considerations
• Knowledge of position, drift rates
• Accuracy and precision of mN thruster
• Contamination and EMI
• Integration with science duty cycles, power
  availability and overall mission requirements