Micropropulsion is an enabling technology for microspacecraft operations by
making missions possible that otherwise could not be performed. For example,
the formation and maintenance of platoons of microspacecraft will require a maneuvering
capability to counter orbital perturbations. Microspacecraft missions
involving large spacecraft resupply, repair, or surveillance will also require maneuverability.
The mission requirements for microspacecraft will be varied and, in
some cases, a large range of capability might be required on the same spacecraft.
Micropropulsion systems must be extremely versatile to address these requirements.
It is clear that there is a need for these systems-from high thrust chemical
engines to high specific impulse electric thrusters-to fulfill specific missions, just
as there is a need for larger spacecraft.
This volume was envisioned to show the state-of-the-art in micropropulsion
concepts and activities at the early stages in the development of this new and exciting
research area. It is the editors' hope that the task of updating the technological
advances in micropropulsion be taken up some years from now and compared with
this early work.