Micro-Arcsecond X-ray Imaging Mission, Pathfinder (MAXIM-PF)
Download
1 / 28

Gabe Karpati May 17, 2002 - PowerPoint PPT Presentation


  • 90 Views
  • Uploaded on

Micro-Arcsecond X-ray Imaging Mission, Pathfinder (MAXIM-PF). System Overview. Gabe Karpati May 17, 2002. Outline. Requirements & Assumptions Baseline Configuration Options Considered Comments, Issues, Concerns. Requirements & Assumptions Study Overview. Mission objective

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Gabe Karpati May 17, 2002' - marvin


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Gabe karpati may 17 2002

Micro-Arcsecond X-ray Imaging Mission, Pathfinder (MAXIM-PF)

System Overview

Gabe Karpati

May 17, 2002


Outline
Outline

  • Requirements & Assumptions

  • Baseline Configuration

  • Options Considered

  • Comments, Issues, Concerns

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Requirements assumptions study overview
Requirements & Assumptions Study Overview

  • Mission objective

    • X-ray interferometry mission, a pathfinder to full MAXIM

  • Original requirements

    • As formulated in the Prework and in K. Gendreau’s “going-in-13may02.ppt”

  • Original requirements modified during the study

    • Lifetime for Phase 1: 1 yr required / 50 targets (1wk/target);

    • Lifetime for Phase 2: 3 yrs required / 4 yrs goal (3 wks/target)

  • Additional constraints, challenges

    • 2015 launch

  • Primary purpose of this study

    • Identify mission drivers and breakpoints

    • Identify technologies required

    • Subsystem configuration, mass and cost estimates

  • Length of study

    • 5 days

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Requirements assumptions major driving requirement areas
Requirements & Assumptions Major Driving Requirement Areas

  • High precision pointing

    • Centroid image of a laser beacon for microarcsec LOS alignment

    • Point by referencing microarcsec image of stars or use GPB-like microarcsec grade Super-Gyro

  • Multi s/c formation flying

    • Orbital dynamics: Formation acquisition and control; Orbits; Transfer to L2

    • Propulsion: Thrust needs to vary by several orders of magnitude

    • ACS: Position control to microns over 100’s of m, and to cm’s over 20000 km, knowledge to microns; Retargeting issues

  • Software

    • To accommodate all functions

  • Verification

    • Functional and performance verification 1 g environment

  • Thermal control

    • Handle two thermally very dissimilar mission Phases with one h/w

    • Control to .1 degree to maintain optical figure

    • “STOP” CTE effects

  • Communication

    • Complex communications web: Detector to Ground; Hub to Detector; Hub to FFs; FF to FF; Rough ranging using RF

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Baseline configuration experiment overview
Baseline Configuration Experiment Overview

  • Observatory configuration

    • One Hub spacecraft, one Detector spacecraft, six Free Flyer spacecraft

    • Hub communicates with Detector and the Free Flyers

    • Detector communicates with ground

  • Phase 1: 100 microarcsec Science

    • 2 formation flying objects at 200 km

  • Phase 2: 1 microarcsec Science

    • Hub surrounded by 6 identical Free Flyers in a circle of 200-500 m, Detector at 20,000 km

    • Distance from Hub to Detector: RF ranging course & time of flight for fine ranging and control (~5m)

    • Align Hub and Detector using Superstartracker that centroids the image at the Detector of a LISA - like laser beacon mounted on Hub (microarcsec)

    • LOS pointing: reference beacon image to image of stars in background w/ Superstartracker or use GPB - like Super-Gyro (microarcsec)

    • HUB to FF’s distance: w/ RF ranging course; Laser interferometer fine w/ corner cubes on Hub (~10 um);

    • FF position: use FF startrackers (~arcsecs)looking at LED on Hub

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Baseline configuration experiment overview1
Baseline Configuration Experiment Overview

Diagram courtesy of K. Gendreau

Optics Hub S/C

  • Pitch, Yaw, control to ~ 1 arcsec, roll control to arcmins

  • Pitch, Yaw, Roll Knowledge to +/- 1 arcsecond

  • LOS to target knowledge to ~0.1 milliarcsec (~15 microns @ 20,000 km)

  • FreeFlyer S/C

  • Pitch, Yaw control to ~1 arcsec

  • Pitch, Yaw Knowledge to arcsecs

  • Roll Control to 30 milliarcsecs

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Baseline configuration experiment overview2
Baseline Configuration Experiment Overview

  • Continuous full sun

    • Battery required for safe Phase only

  • Transfer to L2

    • Takes up to 6 months

    • All S/C are attached together

    • High thrust chemical propulsion

    • Transfer stage is jettisoned at L2

  • Communication web

    • HUB to Free Flyers

    • HUB to Detector

    • All Space-Ground communications performed by Detector spacecraft

    • IP, 50 Kbps; One contact day @ DSN 5 Mbps

    • Ranging for collision avoidance

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Baseline configuration overview
Baseline Configuration Overview

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Baseline configuration overview1
Baseline Configuration Overview

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Baseline configuration instrument resources summary
Baseline Configuration Instrument Resources Summary

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Baseline configuration metrology system resources summary
Baseline Configuration Metrology System Resources Summary

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Baseline configuration s c mass summaries
Baseline Configuration S/c Mass Summaries

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Baseline configuration mission mass summary
Baseline Configuration Mission Mass Summary

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Baseline configuration payload cost m
Baseline ConfigurationPayload Cost [$M]

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Baseline configuration hub s c subsystems cost m
Baseline ConfigurationHub S/c Subsystems Cost [$M]

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Baseline configuration detector s c subsystems cost m
Baseline ConfigurationDetector S/c Subsystems Cost [$M]

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Baseline configuration one ff s c subsystems cost m
Baseline ConfigurationOne FF S/c Subsystems Cost [$M]

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Baseline configuration overall cost summary m
Baseline Configuration Overall Cost Summary [$M]

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Additional issues to consider smaller rsdo busses
Additional Issues To ConsiderSmaller RSDO Busses

  • RSDO On-Ramp II in force

  • RSDO On-Ramp IV selection in process

    • Several new buses added, to increase choice

  • Spectrum Astro SA 200B, Bus dry mass = 90 kg

    • Payload Power (OAV) (EOL) / Mass Limit: 86 W / 100 kg

  • Orbital - Microstar, Bus dry mass = 59 kg

    • Payload Power (OAV) (EOL) / Mass Limit: 50 W / 68 kg

  • Ball BCP 600, Bus dry mass = 203 kg

    • Payload Power (OAV) (EOL) / Mass Limit: 125 W / 90 kg

  • Orbital - Leostar, Bus dry mass = 263 kg

    • Payload Power (OAV) (EOL) / Mass Limit: 110 W / 101 kg

  • Surrey - Minisat 400, Bus dry mass = 207 kg

    • Payload Power (OAV) (EOL) / Mass Limit: 100 W / 200 kg

  • TRW - T200A, Bus dry mass = 242 kg

    • Payload Power (OAV) (EOL) / Mass Limit: 94 W / 75 kg

SA 200B

BCP 600

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Additional issues to consider bigger rsdo busses
Additional Issues To ConsiderBigger RSDO Busses

  • Swales EO-SP (new in RSDO II catalog)

    • Bus dry mass = 370 kg

    • Payload Power (OAV) (EOL) / Mass : 80 W / 110kg

  • Spectrum Astro SA 200HP

    • Bus dry mass = 354 kg

    • Payload Power (OAV) (EOL) / Mass Limit: 650 W / 666 kg

  • Lockheed Martin - LM 900

    • Bus dry mass = 492 kg

    • Payload Power (OAV) (EOL) / Mass Limit: 344 W / 470 kg

  • Orbital StarBus

    • Bus dry mass = 566 kg

    • Payload Power (OAV) (EOL) / Mass Limit: 550 W / 200 kg

  • Orbital – Midstar

    • Bus dry mass = 580 kg

    • Payload Power (OAV) (EOL) / Mass Limit: 327 W / 780 kg

  • Ball BCP 2000

    • Bus dry mass = 608 kg

    • Payload Power (OAV) (EOL) / Mass Limit: 730 W / 380 kg

EO-1

Midstar

SA200HP -DS1

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Comments issues and concerns i t requirements verification
Comments, Issues and Concerns I&T, Requirements Verification

  • Environmental verification

    • Standard, per GEVS

  • Any end-to-end testing / verification of the critical subsystems is very difficult or near-impossible in a 1 g environment

    • E-E verification of orbit maintenance and formation flying capabilities near-impossible

    • E-E verification of metrology system near-impossible

    • E-E verification of X-ray beam focus and alignment is difficult

  • Reasonable trades must be made on verification approaches, goals, and requirements

    • That alone is a very significant body of work

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Maturity technologies trl
Maturity,Technologies, TRL

  • MAXIM is feasible !

    • MAXIM does not factor in any unrealistic technology expectations or technologies un-envisionable today

    • Fairly mature and serious plans, even for the metrology

  • Still, a staggering amount of technology development is required:

    • Metrology system: H/w and s/w elements

      • Superstartracker

      • GPB - like Super-Gyro for pointing

    • Software

      • Formation flying and “virtual-one-body” telescope control software

      • Analysis and simulation techniques

    • Propulsion system

      • Very low thrust technologies, extremely variable force thrusters

    • Verification approaches and technologies for FF LAI missions

      • Simulators

    • Low CTE optical/structural materials

  • General TRL Level of MAXIM key technologies today is 2-3

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Tall poles
TallPoles

  • Tall Pole 1: Multi s/c formation flying

    • ACS: Position control to microns over 100’s of m, and to cm’s over 20000 km, knowledge to microns; Retargeting issues

    • Orbital dynamics: Formation acquisition and control; Orbits; Transfer to L2

    • Metrology System: swarm sensors, interferometric range sensors, beacon detecting attitude sensors

  • Tall Pole 2: High precision pointing

    • Centroid image of a laser beacon for microarcsec LOS alignment

    • Point by referencing microarcsec image of stars or use GPB-like microarcsec grade Super-Gyro

  • Tall Pole 3: Software

    • To accommodate all required functions

  • Tall Pole 4: Propulsion

    • Continuous smooth micro-thrusters

    • Thrusters force variable by orders of magnitude

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Tall poles1
TallPoles

  • Tall Pole 5: Verification science

    • Theoretical “risk-science” assessment on feasible verification vs. available resources

    • Functional and performance verification in 1 g environment

    • “STOP” CTE effects

  • Tall Pole 6: Thermal control

    • Control to .1 degree to maintain optical figure

    • Handle two thermally very dissimilar mission phases with one h/w

  • Tall Pole 7: Communication

    • Complex communications web: Detector to Ground; Hub to Detector; Hub to FFs; FF to FF; Rough ranging using RF

  • Tall Pole 8: Mirror element actuators & software

  • General TRL Level of key technologies today is 2-3

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Additional issues to consider
Additional Issues To Consider

  • Startracker on FF opposite the Hub – Sun line would stare at Sun

    • Since 6 FF’s are 60 degrees apart, roll entire formation, to have two FFs closest to Hub – Sun line at equal 30 degrees

    • This concept doesn’t work for a higher number of FF’s, unless FF startracker FOV is sufficiently narrowed (complicates access to star-field)

  • Structural-Optical-Thermal effects

    • Not fully addressed yet

    • Thermal control to 1.5 mK required – not trivial !

    • Lower CTE optical/structural materials?

  • Structural stability between the attitude sensor and the instrument

    • It is good practice to mount the attitude sensors and the instrument on a common temperature controlled optical table

  • Free Flyers station fixed

    • Free Flyer station clocking position in circle around Hub is constrained

      • To change position, while keeping mirrors in alignment requires rolling the FF s/c

      • Rolling of FF s/c is disallowed for sun / anti-sun sides must be pointed right

    • Mounting FF Mirror Assemblies on turntable would allow repositioning of any FF s/c to any station

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Additional issues to consider1
Additional Issues To Consider

  • Other mission orbits should be fully explored

    • Earth leading/trailing drift away orbit at .1 AU/year

    • Distant retrograde orbits

    • Solar-libration: “kite-like” solar sail “floating” on a toroid-like pseudo-libration surface which envelops L1 between Sun-Earth

  • Calibration Plan

    • Calibration may be a major requirements driver, must be factored in early on

  • Communications network architecture

    • Communications between constellation elements: much refinement is required

  • TDRSS at L2? Servicing at L2?

    • Explore synergies and joint funding possibilities w/ other LAI missions at L2

  • Servicability at L2

    • Design shouldn’t of the bat preclude future serviceability

    • Coordinate w/ servicing planners

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Supporting data
Supporting Data

  • Systems spreadsheet tool: “LAI-MAXIM-PF_System_Sheets.xls”

    • System configuration summaries

    • Mass and cost rollups and detailed ISIS subsystem data

    • Quick propulsion calculator

    • Prework information

  • WBS template: “Generic_WBS_Template_by_GSFC_NOO.doc”

    • Full NASA mission’s complete Work Breakdown Structure

    • Compiled by GSFC New Opportunities Office

  • Useful web sites

    • Access to Space at http://accesstospace.gsfc.nasa.gov/ provides launch vehicle performance information and other useful design data.

    • Rapid Spacecraft Development Office at http://rsdo.gsfc.nasa.gov/ provides spacecraft bus studies and procurement services.

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center


Gabe karpati may 17 2002

System Summary

  • GSFC Contact: Keith Gendreau

  • Phone Number: 301/286-6188

  • Mission name and Acronym: MAXIM-Pathfinder

  • Authority to Proceed (ATP) Date: Dec 2007

  • Mission Launch Date: 2015

  • Transit Cruise Time (months): n/a

  • Mission Design Life (months): 48

  • Length of Spacecraft Phase C/D (months):72

  • Bus Technology Readiness Level (overall): 3

  • S/C Bus management build: TBD

  • Experiment Mass: 3000kg

MAXIM-PF, May 13-17, 2002Goddard Space Flight Center