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Brief Description of theMicrogravity Analysis Software System (MASS)

Alan ChmielKen Hrovat

Brad Humphreys

Acronyms & AbbreviationsGRC Glenn Research Center

ISS International Space StationSAMS Space Acceleration Measurement SystemMAMS Microgravity Acceleration Measurement SystemMASS Microgravity Analysis Software System

RF Refrigerator/FreezerTSC Telescience Support Center

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Simplified Data Flow Diagram

Measurementdevice

Dataacquisition

Downlink

Archiver

Real-timeprocessing/

analysis

Display(internet or

intranet)Database

Massstorage

Off-line (in-depth)analysis/display

Knowledge base,technical papers,

etc.

SAMSMAMS

onISS

MASSat

GRC TSC Database/archive rely on good time stamps. For high-rate data, mass storage can be huge. Archiver can be configured to seek “power of two”

file lengths.

Interactive,specialized

analysis.

Questions: Number of channels? Sample rates per channel? Recording spans per channel? Where would we break into your data flow?

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Archive File Pair Example

Each archive file pair consists of data and header parts:– Data part stored in (efficient) binary format– Header part stored in human-readable text format– Routine that writes these archive files can be configured for “power of two”

data length or other considerations

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Qualify Disturbances

Analysis Example

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Quantify DisturbancesShuttle Primary

Reaction Control System (PRCS) Thruster Firing

~ 50 mg

Analysis Example

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12

12 hours

Spectrogram boundaries & structure in time and frequency

Why is RF # 2 working so much?

over 2 hours!

Analysis Example

7Principal Component Spectral Analysis: summarize acceleration spectrum

Exercise

Vehicle structural

modes

SLEEP

WAKE

Centrifuge

Antenna dither1

2LSLE refrigerator compressors

span > 15 days

Analysis Example

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Screenshot of Off-Line Analysis Tool