Project Title:

Magnetostrictive, Active-Member Control of Space Structures

04.14-0540
NAS7-1091
Magnetostrictive, Active-Member Control of
	Space Structures
Satcon Technology Corporation
	12 Emily Street
	Cambridge, MA 02139-4507
		Bruce G. Johnson
(617-661-0540)

Abstract:

	Large space structures--characterized by low natural frequencies, lightly damped
structural modes, and stringent shape control requirements--pose unique and difficult
control problems. One promising approach uses active truss members that incorporate
sensors and actuators and allow both closed-loop control of the space structure shape
and suppression of unwanted structural vibrations. In the past, these active truss
members have incorporated piezoelectric or electrodynamic actuators. Recent developments
in magnetostrictive materials, however, offer the opportunity for increased strain,
increased power density, and decreased hysteresis compared to piezoelectric materials.
For example, maximum strains and power densities can be over an order of magnitude
higher than for piezoelectric materials. Innovations are needed, however, to integrate
these high-performance magnetostrictive materials into active truss members. This
effort will develop advanced active truss members based on magnetostrictive materials
including the associated sensors and controller.

Potential Commercial Application:

Potential Commercial Applications: Active structure control could be applied in vibration
absorption, vibration isolation, and noise control for inertial instrument test tables,
crystal growing, optical test benches, and vibration reduction in large mechanical
systems.