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16 MEMS and Microstructures in Aerospace Applications

providing this sampling of developments is to provide the reader with insight into
the current state of the practice as an aid to predicting where this technology might
eventually take us. A vision will then be presented, from a NASA perspective, of
application areas where MEMS technology can possibly be exploited for science
and exploration-mission applications.

2.2 RECENT MEMS TECHNOLOGY DEVELOPMENTS FOR
SPACE MISSIONS
It is widely recognized that MEMS technology should and will have many useful
applications in space. A considerable amount of the literature has been written
describing in general terms the ways in which MEMS technology might enable
1
constellations of cost-effective microsatellites for various types of missions and
2
highly miniaturized science instruments as well as such advancements as ‘‘Lab on
a Chip’’ microsensors for remote chemical detection and analysis. 3
Recently, several of the conceptual ideas for applying MEMS in future space
missions have grown into very focused technology development and maturation
projects. The activities discussed in this section have been selected to expose the
reader to some highly focused and specific applications of MEMS in the areas of
spacecraft thermal control, science sensors, mechanisms, avionics, and propulsion.
The intent here is not to provide design or fabrication details, as each of these areas
will be addressed more deeply in the following chapters of this book, but rather to
showcase the wide range of space applications in which MEMS can contribute.
While there is clearly a MEMS-driven stimulus at work today in our community
to study ways to re-engineer spacecraft of the future using MEMS technology, one
must also acknowledge the reality that the space community collectively is only in
the nascent phase of applying MEMS technology to space missions. In fact, our
community probably does not yet entirely understand the full potential that MEMS
technology may have in the space arena. True understanding and the knowledge it
creates will only come with a commitment to continue to create innovative designs,
demonstrate functionality, and rigorously flight-validate MEMS technology in the
actual space environment.

2.2.1 NMP ST5 THERMAL LOUVERS
The Space Technology-5 (ST5) project, performed under the sponsorship of
NASA’s New Millennium Program (NMP), has an overall focus on the flight
validation of advanced microsat technologies that have not yet flown in space
in order to reduce the risk of their infusion in future NASA missions. The NMP
ST5 Project is designing and building three miniaturized satellites, shown in
Figure 2.1, that are approximately 54 cm in diameter, 28 cm in height, and with a
mass less than 25 kg per vehicle. As part of the ST5 mission these three microsats
will perform some of the same functions as their larger counterparts.
One specific technology to be flight validated on ST5 is MEMS shutters for
‘‘smart’’ thermal control conceptualized and tested by NASA’s Goddard Space Flight

© 2006 by Taylor & Francis Group, LLC