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NASA NTRSDate not supplied

MSFC Thermal Testing Lessons Learned Course. Section 3: Lessons Learned from Protoflight StarBurst Instrument Thermal Vacuum Test

MSFC thermal engineers will be presenting lessons learned while preparing and conducting thermal tests. This course will cover practical real world examples of thermal chamber and vacuum chamber testing from engineering development units to system level testing on flight hardware. Special topics include large scale testing preparation, requirement tailoring from parent documents, and cryogenic development testing.

thermal discipline↗
NASA NTRS2008

Swift BAT Instrument Thermal Control System Recovery after Spacecraft Safehold in August 2007

The Swift mission Burst Alert Telescope (BAT) Detector Array thermal control system includes two propylene loop heat pipes (LHPs), eight ammonia constant conductance heat pipes (CCHPs), a radiator that has AZ-Tek's AZW-LA-II low alpha white paint, and precision heater controllers that have adjustable set points in flight. The Power Converter Box (PCB) and Image Processor Electronics (IPE) boxes (a primary and a redundant) of the BAT have Z93P white paint radiators. Swift was successfully launched into orbit on November 20, 2004. The spacecraft (S/C) was placed into a safehold mode on August 10, 2007 after an anomaly on inertial reference unit (IRU) #3. It was returned to inertial pointing on August 16 and instrument power up followed. This paper presents a thermal assessment of the BAT instrument thermal control system (TCS) shut down and recovery as a result of the S/C safehold mode. The recovery required starting up the LHPs manually.

Choi, Michael K.↗
NASA NTRS2019

Optical Instrument Thermal Control on the Large Ultraviolet/Optical/Infrared Surveyor

The Large Ultraviolet/Optical/Infrared Surveyor (LUVOIR) is a multi-wavelength observatory commissioned by NASA as one of four large mission concept studies for the Astro2020 Decadal Survey. Two concepts are under study which bound a range of cost, risk, and scientific return: an 8-meter diameter unobscured segmented aperture primary mirror and a 15-meter segmented aperture primary mirror. Each concept carries with it an accompanying suite of instruments. The Extreme Coronagraph for Living Planetary Systems (ECLIPS) is a near-ultraviolet (NUV) / optical / near-infrared (NIR) coronagraph; the LUVOIR Ultraviolet Multi-object Spectrograph (LUMOS) provides multi-object imaging spectroscopy in the 100-400 nanometer ultraviolet (UV) range; and the High Definition Imager (HDI) is a wide field-of-view near-UV / optical / near-IR camera that can also perform astrometry. The 15-meter concept also contains an additional instrument, Pollux, which is a high-resolution UV spectro-polarimeter. While the observatory is nominally at a 270 Kelvin operational temperature, the requirements of imaging in both IR and UV require separate detectors operating at different temperature regimes, each with stringent thermal stability requirements. The change in observatory size requires two distinct thermal designs per instrument. In this current work, the thermal architecture is presented for each instrument suite. We describe here the efforts made to achieve the target operational temperatures and stabilities with passive thermal control methods. Additional discussion will focus on how these instrument thermal designs impact the overall system-level architecture of the observatory and indicate the thermal challenges for hardware implementation.

Decadal Study↗
NASA NTRS2019

Optical Instrument Thermal Control on the Large Ultraviolet/Optical/Infrared Surveyor

The Large Ultraviolet/Optical/Infrared Surveyor (LUVOIR) is a multi-wavelength observatory commissioned by NASA as one of four large mission concept studies for the Astro2020 Decadal Survey. Two concepts are under study which bound a range of cost, risk, and scientific return: an 8-meter diameter unobscured segmented aperture primary mirror and a 15-meter segmented aperture primary mirror. Each concept carries with it an accompanying suite of instruments. The Extreme Coronagraph for Living Planetary Systems (ECLIPS) is a near-ultraviolet (NUV) / optical / near-infrared (NIR) coronagraph; the LUVOIR Ultraviolet Multi-object Spectrograph (LUMOS) provides multi-object imaging spectroscopy in the 100-400 nanometer ultraviolet (UV) range; and the High Definition Imager (HDI) is a wide field-of-view near-UV / optical / near-IR camera that can also perform astrometry. The 15-meter concept also contains an additional instrument, Pollux, which is a high-resolution UV spectro-polarimeter. While the observatory is nominally at a 270 Kelvin operational temperature, the requirements of imaging in both IR and UV require separate detectors operating at different temperature regimes, each with stringent thermal stability requirements. The change in observatory size requires two distinct thermal designs per instrument. In this current work, the thermal architecture is presented for each instrument suite. We describe here the efforts made to achieve the target operational temperatures and stabilities with passive thermal control methods. Additional discussion will focus on how these instrument thermal designs impact the overall system-level architecture of the observatory and indicate the thermal challenges for hardware implementation.

LUVOIR↗
NASA NTRS2011

The Prototype HyspIRI Thermal Infrared Radiometer (PHyTIR): A High Speed, Multispectral, Thermal Instrument Development in Support of HyspIRI-TIR

The Prototype HyspIRI Thermal Infrared Radiometer (PHyTIR) is being developed as part of the risk reduction activities associated with the Hyperspectral Infrared Imager (HyspIRI). The HyspIRI mission was recommended by the National Research Council Decadal Survey and includes a visible shortwave infrared (SWIR) pushboom spectrometer and a multispectral whiskbroom thermal infrared (TIR) imager. Data from the HyspIRI mission will be used to address key science questions related to the Solid Earth and Carbon Cycle and Ecosystems focus areas of the NASA Science Mission Directorate. The HyspIRI TIR system will have 60m ground resolution, better than 200mK noise equivalent delta temperature (NEDT), 0.5C absolute temperature resolution with a 5-day repeat from LEO orbit. PHyTIR addresses the technology readiness level (TRL) of certain key subsystems of the TIR imager, primarily the detector assembly and scanning mechanism. PHyTIR will use Mercury Cadmium Telluride (MCT) technology at the focal plane and operate in time delay integration mode. A custom read out integrated circuit (ROIC) will provide the high speed readout hence allowing the high data rates needed for the 5 day repeat. PHyTIR will also demonstrate a newly developed interferometeric metrology system. This system will provide an absolute measurement of the scanning mirror to an order of magnitude better than conventional optical encoders. This will minimize the reliance on ground control points hence minimizing post-processing (e.g. geo-rectification computations).

National Research Council Decadal Survey↗
NASA NTRS2011

Testing of a Wireless Sensor System for Instrumented Thermal Protection Systems

Funded by NASA's Constellation Universities Institutes Project (CUIP), we have been developing and testing a system to wirelessly power and collect data from sensors on space platforms in general and, in particular, the harsh environment of spacecraft re-entry. The elimination of wires and associated failures such as chafing, sparking, ageing, and connector issues can increase reliability and design flexibility while reducing costs. These factors present an appealing case for the pursuit of wireless solutions for harsh environments, particularly for their use in space and on spacecraft. We have designed and built a prototype wireless sensor system. The system, with capabilities similar to that of a wired sensor system, was tested in NASA Ames Research Center s Aerodynamic Heating Facility and Interaction Heating Facility. This paper discusses the overall development effort, testing results, as well as future directions.

Kummer, Allen T.↗
NASA NTRS1975

Development of TPS flight test and operational instrumentation

Thermal and flow sensor instrumentation was developed for use as an integral part of the space shuttle orbiter reusable thermal protection system. The effort was performed in three tasks: a study to determine the optimum instruments and instrument installations for the space shuttle orbiter RSI and RCC TPS; tests and/or analysis to determine the instrument installations to minimize measurement errors; and analysis using data from the test program for comparison to analytical methods. A detailed review of existing state of the art instrumentation in industry was performed to determine the baseline for the departure of the research effort. From this information, detailed criteria for thermal protection system instrumentation were developed.

Carnahan, K. R.↗
NASA NTRS1999

Significance of Landsat-7 Spacecraft Level Thermal Balance and Thermal Test for ETM+Instrument

The thermal design and the instrument thermal vacuum (T/V) test of the Landsat-7 Enhanced Thematic Mapper Plus (ETM+) instrument were based on the Landsat-4, 5 and 6 heritage. The ETM+ scanner thermal model was also inherited from Landsat-4, 5 and 6. The temperature predictions of many scanner components in the original thermal model had poor agreement with the spacecraft and instrument integrated sun-pointing safehold (SPSH) thermal balance (T/B) test results. The spacecraft and instrument integrated T/B test led to a change of the Full Aperture Calibrator (FAC) motor stack "solar shield" coating from MIL-C-5541 to multi-layer insulation (MLI) thermal blanket. The temperature predictions of the Auxiliary Electronics Module (AEM) in the thermal model also had poor agreement with the T/B test results. Modifications to the scanner and AEM thermal models were performed to give good agreement between the temperature predictions and the test results. The correlated ETM+ thermal model was used to obtain flight temperature predictions. The flight temperature predictions in the nominal 15-orbit mission profile, plus margins, were used as the yellow limits for most of the ETM+ components. The spacecraft and instrument integrated T/B and TN test also revealed that the standby heater capacity on the Scan Mirror Assembly (SMA) was insufficient when the Earth Background Simulator (EBS) was 1 50C or colder, and the baffle heater possibly caused the coherent noise in the narrow band data when it was on. Also, the cooler cool-down was significantly faster than that in the instrument T/V test, and the coldest Cold Focal Plane Array (CFPA) temperature achieved was colder.

Choi, Michael K.↗
NASA NTRS1989

NCTM workshop splinter session, IR thermal measurement instruments

The splinter session dealing with commercial industrial thermal measurement state-of-the-hardware had a total attendance of 15. Two papers were presented in the splinter session as follows: (1) Development of an Infrared Imaging System for the Surface Tension Driven Convection Experiment, Alexander D. Pline, NASA LeRC; (2) A Space-qualified PtSi Thermal Imaging System, Robert W. Astheimer, Barnes Engineering Div., EDO Corp. In addition a brief description of SPRITE detector technology was presented by Richard F. Leftwich of Magnovox. As anticipated, the discussions were concerned mainly with thermal imaging figures of merit rather than those for point measurement instruments. The need for uniform guidelines whereby infrared thermal imaging instruments could be specified and evaluated was identified as most important, particularly where temperature measurements are required. Presently there are differences in the way different manufacturers present significant performance parameters in their instrument data sheets. Furthermore, the prospective user has difficulty relating these parameters to actual measurement needs, and procedures by which performance can be verified are poorly defined. The current availability of powerful thermal imaging diagnostic software was discussed.

Kaplan, Herbert↗
NASA NTRS2018

A Thermal Imaging Instrument with Uncooled Detectors

In this work, we performed an instrument concept study for sustainable thermal imaging over land with uncooled detectors. We evaluated two different uncooled detector technologies uncooled microbolometers and thermopiles. We have also evaluated materials for use in in a uncooled thermopile detector concept.

Thermal↗