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Autonomous Large Distributed CubeSat Space Telescope (ALDCST). ASTE 527: Space Exploration Architectures Concepts Synthesis Studio Midterm Presentation October 16, 2012 Professor: Madhu Thangavelu Concept Presentation: Jesus Isarraras. BACKGROUND / HISTORY. NASA
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Autonomous Large Distributed CubeSat Space Telescope (ALDCST) ASTE 527: Space Exploration Architectures Concepts Synthesis Studio Midterm Presentation October 16, 2012 Professor: Madhu Thangavelu Concept Presentation: Jesus Isarraras
BACKGROUND / HISTORY • NASA • Hubble Space Telescope; ~570km LEO orbit; 2.4m mirror aperture • James Webb Space Telescope scheduled for launch in 2018; 1.5M km (Earth-Sun Lagrangian L2) orbit; 6.5m mirror aperture • Studying next generation UVOIR space observatory through the Advanced Technology Large-Aperture Space Telescope (ATLAST) • California Polytechnic State University & Stanford • Developed CubeSat Standard • Cal Tech & University of Surrey • Autonomous Assembly of a Reconfigurable Space Telescope (AAReST) Technology Development • Surrey Training Research and Nanosatellite Demonstrator (STRaND) payload development for AAReST • Naval Post Graduate School • Pseudospectral Estimation for optimal controls problems
RATIONALE • Develop key technologies and architectures for large space apertures to improve the capability of future imaging and sensing using CubeSat innovations http://www.jwst.nasa.gov/comparison.html
TIMELINE OF TECHONOLOGIES FOR ADVANCED TELESCOPES Direct Tech Insert JWTS Direct Tech Insert ARReST STRaND-2 ATLAST-8m ATLAST-9.2m ATLAST-16m STRaND-1 Payload contains Google Nexus Smartphone; Nexus will fully control nanosat S-Android Logo Kinect Kinect Tech for 3D modeling spacial awareness S-Android Logo
ASSUMPTIONS / GROUNDRULES • Time frame: 10 years • Successful STRaND – 1 mission in 2012 • Successful STRaND – 2 mission in 2014 • Successful ARReST mission in 2015 • Successful JWTS launch and mission in 2018 • Adaptive Optics • Gap size between sub-mirrors is < 0.01D; aberration is minimized
CONCEPT - PROPOSAL • Provide an alternative architecture for large primary mirror (D>20m) for space telescopes • Alternative for next generation UVOIR telescopes (e.gATLAST) • CubeSat cluster with segmented mirrors • Autonomous formation and control • Potential Benefits • Potential lower cost and mass • Mirror segment replacement • Removes human activity for fielding • Faster production/manufacturing http://www.jwst.nasa.gov/comparison.html
CONCEPT - LOCATION • Direct extrasolar planetary observations become possible with large (D>20m) apertures • Earth-Sun Lagrangian point L2 • Opportunity to study early universe phenomena, monitor extremely faint and distant galaxies, dark matter and dark energy http://www.jwst.nasa.gov/comparison.html
CHALLENGES • Deployable mirror segment alignment • Achieving high surface accuracy of a large segmented mirror (optical figuring) • Surface and structure control stabilization • Vibration isolation and potential jitter control • Control of adaptable/flexible mirrors • Wavefrontsensing and correction (sensors) • Thermal management/distortion mitigation • Power management of segmented architecture
COMPLEX SUBSYSTEMSArchitecture - Structure • Launcher to hold multiple layers • Layers deployed in sequence • Each layer contains 6 segments • Each segment contains N mirrors 2nd Inner Layer 2 1 1st Inner Layer (center) Nth Layer N Launcher
COMPLEX SUBSYSTEMSArchitecture - Structure Nth CubeSat Layer of Mirror Hex-Frame: provides stability and links Pod’s together Top view of Nth Layer Flexible joints connecting sat’s Top view of Nth Layer • Expands to create Hexagon Shape
COMPLEX SUBSYSTEMSArchitecture - Structure • Autonomous formation • Control • ADC • Advanced algorithms (e.g PS) • Sensing • Lasers, optical, IR • Actuation • Cold Gas, PPT, Hall • Comm • Short range wireless • LOS Wireless • Laser
COMPLEX SUBSYSTEMSArchitecture – Structure Layers 100 mirrors 100 mirrors 99 mirrors 99 mirrors Total Mirrors: 30,300 Total CubeSats: 30,300 Total Layers: 5,050 Total Segments: 600
CONCEPT - COMPLEX SUBSYSTEMSArchitecture – Deformable Mirror • Thin deformable mirrors with integrated actuators • >200 independent actuators • Wavefront correction for each mirror (algorithms) • Improved light gathering power • Improved resolution • Thermal management through shape/curvature correction Primary material: Polyvinylidene flouride (PVDF) 370μm http://www.kiss.caltech.edu/study/largestructure/technology.html
CONCEPT - COMPLEX SUBSYSTEMSArchitecture – Advanced GN&C • Pseudo-spectral estimation • GN&C stability of complete cluster structure • Optimal motion planning for autonomous vehicles in obstacle rich environments • Constraint Non-Linear Problems The Zero Propellant Maneuver demonstrated on the ISS. November 5, 2006 rotated 90 deg and March 3, 2007 rotated 180 degrees Autonomous Reentry and Decent of Reusable Launch Vehicles
CONCEPT - EVOLUTION • Mirror packaging • Mirror wavefrontsensors • Flight formation sensors • Adaptive optics systems • Mirror actuators • CubeSat P-POD and dimension growth • Instrumentation (cameras, sensors, etc)
CONCLUSIONS • Large apertures can be created through CubeSat Cluster design • Segmented and adaptable mirrors future of telescope design • Complex CubeSat architectures affordable options of the future
FUTURE QUANTITATIVE STUDY • Secondary Mirror Deployment • Aberration and Mirror stabilization • Orbit definition • Thermal management of cubesat’s and system architecture (e.g Passive – radiate heat to space vs active – refrigerator system) • Sun shield technology • Radiation hardening requirements • Power Management • Communication architecture
REFERENCES • Patterson, K., Yamamoto, N., Pellegrino, S. (2012). Thin deformable mirrors for a reconfigurable space telescope. Retrieved from http://pellegrino.caltech.edu/PUBLICATIONS/AIAA_SDM2012_1220023%20(2).pdf • Postman, M. (2009). Advanced Technology Large Aperture Space Telescope Study NASA. Retrieved from http://www.stsci.edu/institute/atlast/documents/ATLAST_NASA_ASMCS_Public_Report.pdf • Keck Institute for Space Studies. (2012)http://www.kiss.caltech.edu/lectures/index.html • Steeves, J., Patterson, K., Yamamoto, N., Kobilarov, M., Johnson, G., Pellegrino, S. (2012). AAReST Technology Development. Retrieved from http://kiss.caltech.edu/workshops/smallsat2012/presentations/steeves.pdf • Patterson, K., Pellegrino, S., Breckinridge, J. (TBD) Shape correction of thin mirrors in a reconfigurable modular space telescope. Retrieved from: http://www.kiss.caltech.edu/study/largestructure/papers/patterson-pellegrino-breckinridge.pdf • McClellan, J. (TBD). Aurora Flight Sciences CubeSat Cluster. Retrieved from: http://icubesat.files.wordpress.com/2012/06/icubesat-org-2012-c-3-3-_presentation_mccellan_201205251247.pdf • Padin, S. (2003). Design Considerations for a Highly Segmented Mirror. Retrieved from: http://authors.library.caltech.edu/5664/1/PADao03b.pdf • Postman, M. (2007). Advanced Technology Large-Aperture Space (ATLAS) Telescope: A Technology Roadmap for the Next Decade. Retrieved from: http://www.stsci.edu/institute/atlast/documents/Submitted_proposal_TEAM_DISTN.pdf • Fundamental Optics. Retrieved from: http://cvimellesgriot.com/Products/Documents/TechnicalGuide/Fundamental-Optics.pdf • Naval Post Graduate School. (2012). Conference Papers. Retrieved from: http://www.nps.edu/academics/gnclab/Conference.html
Thank you for your time! Jesus Isarraras isarrara@usc.edu
CONCEPT - COMPLEX SUBSYSTEMSLarge Space Aperture Architecture Comparison
Preliminary Mass Calculations • From Patterson, K., Pellegrino, S., Breckinridge, J. Shape correction of thin mirrors in a reconfigurable modular space telescope Complete mirror structure w/ areal density ~2kg/m^2:
COMPLEX SUBSYSTEMSArchitecture - Structure • Hex-Frame Contains • ADC • Comm Link Enhancement • Layer Stabilization • Network Communication
CONCEPT - COMPLEX SUBSYSTEMSArchitecture – Secondary Mirror & Instruments 10cm 10cm 6U CubeSat Focal Plane Detector Secondary Mirror Deployer Instruments (Camera, Optical/IR Sensors, etc)
Formation Flying Control Challenges • Complexity • Systems of systems (interconnection/coupling) • Communication and Sensing • Limited bandwidth, connectivity, and range • What? When? To whom? • Data Dropouts, Robust degradation • Arbitration • Team vs. Individual goals • Resources • Always limited, especially on a CubeSat
Hubble Space Telescope • Payload: Optics: The telescope is an f/24 Ritchey-Chretien Cassegrainian system with a 2.4 m diameter primary mirror and a 0.3 m Zerodur secondary. The effective focal length is 57.6m. The Corrective Optics Space Telescope Axial Replacement (COSTAR) package is a corrective optics package designed to optically correct the effects of the primary mirror's aberration on the Faint Object Camera (FOC), Faint Object Spectrograph (FOS), and the Goddard High Resolution Spectrograph (GHRS). COSTAR displaced the High Speed Photometer during the first servicing mission to HST.
Hubble Space Telescope • Instruments: The Wide Field Planetary Camera (JPL) consists of four cameras that are used for general astronomical observations from far-UV to near-IR. The Faint Object Camera (ESA) uses cumulative exposures to study faint objects. The Faint Object Spectrograph (FOS) is used to analyze the properties of celestial objects such as chemical composition and abundances, temperature, radial velocity, rotational velocity, and magnetic fields. The FOS is sensitive from 1150 Angstroms (UV) through 8000 Angstroms (near-IR). The Goddard High Resolution Spectrometer (GHRS) separates incoming light into its spectral components so that the composition, temperature, motion, and other chemical and physical properties of objects can be analyzed. The HRS is sensitive between 1050 and 3200 Angstroms.