Concept design of a new space telescope with deployable composite booms Student project Course: “Strutture per veicoli spaziali” Politecnico di Torino A.A. 2020/2021 AUTHORS Team #1 (Chapters 1, 8) Ainardi Alessandro Alleruzzo Gianluca Barca Emanuele Bona Davide Cisternino Luigi Delpiano Davide De Stefano Matteo De Trane Giorgio Filippi Matteo Forte Piermatteo Guidi Manuel La Bella Emanuela Maffucci Marco Maldera Federico Martín Velazquez Antonio Mazza Cesare Mugoni Chiara Paschero Matteo Pennisi Andrea Santoro Alessandro Scalise Antonio Scancella Lorenzo Sibilla Mario Sica Andrea Siena Andrea Tagliani Gianluca Tarditi Simone Team #2 (Chapters 2, 7 and Appendices) Barberis Beniamino Biddau Luca Bronca Pietro Bruno Michele Cisaria Pietro Ciuffreda Samuele Favia Alessandro Friolotto Vittorio Iapichello Andrea Mai Cosimo Luigi Malagni Ludovica Manganiello Alessandro Marampon Davide Meloni Francesco Moreno Toledo Sonsoles Parrinello Domenico Peluso Alessandro Pipolo Serena Pistone Vittorio Revilla Veleda Javier Russo Emanuele Speziale Alessia Stella Giovanni Ungaro Francesco Viola Pasquale Vottero Davide Team #3 (Chapters 3, 6) Amore Daniele Amorosino Simone Antetomaso Valentina Barletta Stefano Bosi Rossella Breda Alessandro Carlucci Alessio Coco Stefano Cossu Antonio D'Agostino Simona Di Donna Arsenio Maria Dinolfo Giuseppe Fabro Davide Felli Ivan Florea Alexandru Folcarelli Lorenzo Gedda Giacomo Grasso Davide Grimaldi Giovanni Gutierrez Gabriel Jose Iannotta Domenico Andrea Lezzoche Domenico Morello Angelo Luca Musacchio Andrea Urso Elisabetta Vinella Emanuele Team #4 (Chapters 4, 5) Martina Cappa Enrico Edoardo Zini Enrico Rutigliano Serena Campioli Donato Russo Giorgio Chiofalo Andrea Pandolfo Adriano Palumbieri Simone Antonino Valeria Dessanti Federica Cardinale Ciccotti Francesco Lucia Rosa Tarda Ludovico Pernazza Daniele Greco Mariano Oliva Michele Pepe Francesco Manconi Rebecca Masia Giovan Battista Alogna Francesco Laudadio Tommaso Zanatta Vincenzo Alberto di Michele Christian Di Sannio Giuseppe Azzarelli SUPERVISORS Prof. A. Pagani Prof. E. Carrera Prof. M. Filippi Dr. A.R. Sanchez-Majano TABLE OF CONTENTS 1 State of the art of telescopes with tape spring-based secondary mirrors and active correction capabilities .......................................................................................................................... 1 1.1 Space Telescopes .................................................................................................................... 1 1.1.1 Space Telescope’s Traditional Configuration ................................................................... 1 1.1.2 Advantages and Disadvantages of Space Telescopes ...................................................... 2 1.1.3 Missions ........................................................................................................................... 3 1.1.4 Active Space Telescopes .................................................................................................. 5 1.2 Deployable Telescopes............................................................................................................ 8 1.2.1 Tape Spring Hexapod for Deployable Telescope Dynamics ............................................. 9 1.2.2 Halca .............................................................................................................................. 10 1.2.3 DISCIT ............................................................................................................................ 12 1.2.4 Low cost Deployable Telescope for Small Satellite ........................................................ 13 1.2.5 FalconSAT-7 ................................................................................................................... 13 1.2.6 Collapsible Space Telescope for Nanosatellites ............................................................. 14 1.3 Active Control System for Telescope Mirror ......................................................................... 15 1.3.1 Active optics .................................................................................................................. 15 1.3.2 VST – Solutions for the positioning of the secondary mirror ......................................... 16 1.3.3 W.M. Keck Telescopes – Segmented primary mirror active control system ................. 19 1.3.4 SOFIA Telescope – Extremely compact secondary mirror unit ...................................... 21 1.3.5 The Deployable Telescope PistonCam ........................................................................... 24 1.3.6 ATLAST – Hybrid Sensor Active Control (HSAC) Architecture ........................................ 26 1.3.7 Adaptive optics .............................................................................................................. 30 1.3.8 MMT – Unconventional secondary mirror used as corrector for the adaptive optics system 32 1.4 Passive Control System – Pointing ........................................................................................ 34 1.4.1 Gravity Gradient ............................................................................................................ 34 1.4.2 Magnetic Stabilization ................................................................................................... 35 1.4.3 Spin Stabilization ........................................................................................................... 36 1.5 Passive Deployment of Space Telescopes ............................................................................ 37 1.5.1 Spring Hinge .................................................................................................................. 37 1.5.2 Shape Memory Alloys .................................................................................................... 38 1.6 Future trends ........................................................................................................................ 38 1.6.1 James Webb Space Telescope ....................................................................................... 39 1.6.2 LUVOIR .......................................................................................................................... 40 i 1.6.3 HabEx ............................................................................................................................ 41 1.6.4 Lynx X-Ray Observatory ................................................................................................. 41 1.6.5 Origins Space Telescope ................................................................................................ 42 1.6.6 WFIRST .......................................................................................................................... 43 2 Booms: Materials and Configurations ........................................................................................... 45 2.1 Woven materials ................................................................................................................... 45 2.2 Fabrication procedures ......................................................................................................... 46 2.2.1 Resin impregnation ....................................................................................................... 46 2.2.2 Lay-up ............................................................................................................................ 47 2.2.3 Vacuum Stage ................................................................................................................ 47 2.2.4 Autoclave curing ............................................................................................................ 47 2.2.5 Hinge fabrication ........................................................................................................... 48 2.3 Common Materials for Deployable Structures ..................................................................... 48 2.3.1 Materials models and stability....................................................................................... 48 2.3.2 Flexible Composite Tape Springs (FCTS) ........................................................................ 50 2.3.3 Carbon Fiber Reinforced Polymer (CFRP) ...................................................................... 50 2.3.4 Large Strain Composite Materials ................................................................................. 52 2.3.5 Future Large Strain Materials ........................................................................................ 54 2.3.6 Deployment Repeatability Testing of Composite Tape Springs for Space Optics Applications ................................................................................................................................... 54 2.3.7 EMC material s .............................................................................................................. 55 2.3.8 Micro-Structural model ................................................................................................. 56 2.4 Boom Configurations ............................................................................................................ 57 2.4.1 Tape springs .................................................................................................................. 58 2.4.2 Storable Extendible Tubular Member (STEM) booms ................................................... 60 2.4.3 Bi-STEM ........................................................................................................................