Project Title:

High-Precision Spectrometer Movement

08.17-0540A
911685
High-Precision Spectrometer Movement
Satcon Technology Corporation
12 Emily Street
Cambridge
MA
02139-4507
Richard L.
Hockney
617-661-0540
GSFC
NAS5-31922
164

08.17-0540A
911685

Abstract:

High-Precision Spectrometer Movement
Many spacecraft optical/mechanical applications such as spectrometers require high
levels of precision in positioning, precision that is unobtainable with conventional
approaches. Extremely high reliability is also required. A high-precision movement
for spacecraft spectrometers and other optical applications that will satisfy both
of these requirements will be developed and demonstrated. The device will use a two-stage
mechanism combining a novel locking, electromechanical coarse stage with a piezoelectric
fine-pointing stage. The movement has complete rotational freedom about the yaw axis
and allows 5 degrees of motion about the pitch and/or roll axes. Optical components
can be aligned quickly to any orientation within the allowed range of angular motion
with a precision greater than .0007 arc-seconds in roll, pitch, and yaw, and held
in that position indefinitely with negligible power consumption. The coarse stage
combines a novel angular contact ball bearing with spherical symmetry, a spherical
toque motor, and a piezoelectric locking mechanism. The fine stage is based on an
extremely simple six-degree-of-freedom piezoelectric actuation system. Phase I will
include design definition of the device. Phase II will construct, test, and evaluate
a prototype system.
A high-precision optical positioning system combining precision with small-size,
low-noise, low-friction, high-stiffness, and low-consumable requirements would find
immediate acceptance for both instruments and process devices in many specific industrial
and military applications.
spectrometer, gimbal, ultraprecision, optical, interferometer, adaptive, control