The starlight metrology subsystem
Describes a metrology subsystem for NASA's Starlight mission, a space-based separated-spacecraft stellar interferometer.
metrology, stellar interferometry↗
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Results for “METROLOGY”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Metrology sensor characterization and pointing control for the Formation Interferometer Testbed (FIT)
In this paper, the metrology pointing sensor of the Starlight ground instrument prototype is characterized and a siderostat pointing control loop is closed between two optical benches with a 10 meter separation.
interferometry starlight pointing metrology↗
First Tests of the Interferometer in the Micro-Arsecond Metrology Testbed (MAM)
The Space Interferometry Mission (SIM) relies on interferometry and metrology capable of measuring the change in the optical path difference with picometer accuracy.
intrferometry SIM astrometry picometer metrology↗
SRTM metrology system: flight results
An assessment of the inflight performance of the Shuttle Radar Topography Mission (SRTM) Metrology System, also known as the Attitude and Orbit Determination avionics (AODA), is presented. The assessment is based on analysis of raw sensor data obtained during the mission.
IFSAR metrology↗
The SRTM sub-arcsecond metrology camera
This paper provides a description of the metrology camera, the process used to prepare it for flight on SRTM, the LED target development effort, test and alignment issues, and the observed in-flight performance.
metrology interferometry SRTM↗
Antenna auto-calibration and metrology approach for AFRL/JPL space based radar
We present an auto-calibration and metrology system concept to correct for phase errors and mechanical deformation during the misssion.
radar antenna autocalibration↗
Signal processing for order 10 pm accuracy displacement metrology in real-world scientific applications
This paper describes heterodyne displacement metrology gauge signal processing methods that achieve satisfactory robustness against low signal strength and spurious signals, and good long-term stability. We have a proven displacement-measuring approach that is useful not only to space-optical projects at JPL, but also to the wider field of distance measurements.
metrology↗
Signal processing for order 10 PM accuracy displacement metrology gauges in real-world scientific applications
The Space Interferometry Mission (SIM), Terrestrial Planet Finder (TPF) and James Web Space Telescope (JWST) need stable, reliable distance metrology with subnanometer accuracy.
interferometry↗
Absolute optical metrology : nanometers to kilometers
We provide and overview of the developments in the field of high-accuracy absolute optical metrology with emphasis on space-based applications. Specific work on the Modulation Sideband Technology for Absolute Ranging (MSTAR) sensor is described along with novel applications of the sensor.
optical metrology↗
L2 Earth Atmosphere Observatory: Formation Guidance, Metrology and Control Synthesis
The Earth Observatory Formation at L2, a Lagrange libration point, is a unique large aperture (25 m diameter) space telescope concept that will improve the knowledge and understanding of dynamic, chemical and radiative mechanisms that cause changes in the atmosphere, and can lead to the development of models and techniques to predict short and long-term climate changes. The results of this concept definition study show that the telescope concept is feasible, and can have technology readiness in the 2020 time frame. Further advanced development in several subsystems is needed, such as higher efficiency Xenon ion thrusters with throttling, and optical quality large membrane mirror with active shape control. It presents an analysis and solution of guidance, sensing, control, and propulsion problems for a formation of two spacecraft on the Sun-Earth line in the neighborhood of the Sun-Earth L2 point, that observes Earth s atmosphere during continuous solar occultation by the Earth. A system architecture is described for the observatory, and its components that include unique mission specific metrology. The formation must follow a powered trajectory with strictly limited fuel use to observe solar occultation. A configuration of ion thrusters and reaction wheels for translation and attitude control is designed along with algorithms for orbit following and formation control. Simulation results of the orbital and formation dynamics are presented that verify performance of the control systems.
Earth Atmosphere Observatory Formation↗
Large Volume, Optical and Opto-Mechanical Metrology Techniques for ISIM on JWST
The final, flight build of the Integrated Science Instrument Module (ISIM) element of the James Webb Space Telescope is the culmination of years of work across many disciplines and partners. This paper covers the large volume, ambient, optical and opto-mechanical metrology techniques used to verify the mechanical integration of the flight instruments in ISIM, including optical pupil alignment. We present an overview of ISIM's integration and test program, which is in progress, with an emphasis on alignment and optical performance verification. This work is performed at NASA Goddard Space Flight Center, in close collaboration with the European Space Agency, the Canadian Space Agency, and the Mid-Infrared Instrument European Consortium.
ISIM↗
Metrology for Spatial Interferometry
The accuracy of the relative metrology gauge developed for the proposed OSI and SONATA missions is improved to sub-picometer level.
surface↗
SIM internal metrology beam launcher development
In this paper, we present some of the experimental results from a laboratory demonstration unit and design considerations for SIM's internal metrology beam launcher.
metrology↗
Sensitivity of optical metrology calibration to measured corner cube retroreflector parameters for Space Interferometry Mission
Picometer scale optical metrology specifications for the Space Interferometry Mission require precision calibration functions involving the optical and orientation characteristics of corner cube.
corner↗
Demonstration of nm-Level Active Metrology for Long Range Interferometric Displacement Measurements
We report on the laboratory demonstration of an active linear metrology scheme using two separate lasers.
Active↗
Two-Laser Heterodyne Metrology for a Separated Spacecraft Interferometer
The proposed New Millenium Interferometry consists of three spacecraft separated by up to several kilometers. A heterodyne laser metrology system is proposed to measure the relative distances between the spacecraft.
New↗
Metrology system for Space Interferometry Mission system testbed 3
In a 3-baseline interferometer fourteen metrology gauges are used to monitor changes in the two baselines and calculate the length of the third. Simulation for estimating the third baseline indicates measurement capability of better than 1 nm error.
interferometry↗
Deep Space 3 Metrology System
A metrology subsystem on board the Deep Space 3, a separated interferometer mission, is used to determine stellar fringe delay jitter, delay rate, and intial delay.
Deep↗