MEMS Mega-Pixel Micro-Thruster Array

摘要

Small satellites flying in clusters require periodic 'stationkeeping' to keep them in place. The required impulse is very small - the goal is not to keep the individual satellites in rigid formation, but only to keep them in well-defined orbitals with respect to one another. The necessary impulse, therefore, is only the amount needed to overcome the difference in drag between the most-affected and the least-affected satellites in the cluster. Estimates are that the differential drag can be overcome by providing -l uNsec (micro- Newton second) to -l mN sec (milli-Newton gecond) every 10 to 100 seconds throughout each satellite's mission. The system we are developing will do that. The thrusters have very low power and energy thresholds for ignition ( 10 mWatts, 100 Joules), and no moving parts so they are expected to be highly reliable. A single thruster array contains a quarter of a million separate thrusters.