MIDDECK ACTIVE CONTROL EXPERIMENT-II (MACE-II)
Research Area: Small Satellites and Control Technologies
Expedition(s): 1-2
Principal Investigator(s): ● R. Rory Ninneman, Air Force Research Laboratory, Kirtland Air
Force Base, New Mexico
RESEARCH OBJECTIVES
The Middeck Active Control
Experiment-II (MACE-II) allows
engineers to design future
spacecraft and facilities with
lightweight, inexpensive structures
and materials without sacrificing
the stability demanded by sensitive
payloads. MACE-II, the first hands-
on experiment aboard the
International Space Station (ISS),
consists of 2 basic parts that are
designed to detect and
compensate for vibrations. During
experiments, scientists use a
gimbal at one end of the multi-
body platform (MBP) to create a
disturbance that is detected by the
experiment support module (ESM), which then calculates the opposing forces to be applied at
the opposite gimbal, thereby stabilizing the platform. The set of algorithms used by the ESM are
adaptable and can change because of moving parts, variations in temperature, and normal
wear and tear on mechanical systems. A collaborating team at the Massachusetts Institute of
Technology (MIT) plan to study how control systems such as that used for MACE-II can be
applied to hardware and systems that change over time, such as telescopes, antennas, and
robotic arms that must be moved to perform specific duties.
EARTH BENEFITS
The autonomous adaptive control technology demonstrated by MACE-II can be used in any
vehicle that must negotiate turbulent airstreams and atmospheric changes. It can be used to
develop smart, problem-solving auto pilots for commercial jets or better guidance and pointing
systems for military aircraft.
SPACE BENEFITS
MACE-II tested self-reliant, adaptive technologies that can detect problems with ISS hardware
and correct those problems as needed. This reduces the amount of crew and ground-based
personnel time required to monitor and repair ISS hardware. This technique is also critical for
control of large, flexible structures that must perform precision pointing and tracking.
Susan Helms, Expedition 2 flight engineer, works with Middeck
Active Control Experiment-II, which is shown "floating" in the
microgravity environment of the International Space Station.