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Space Elevator Systems Architecture Space Elevator Systems Architecture An initial top-level view of a space elevator concept through space systems architecture and space systems engineering Peter A. Swan, Ph.D. Cathy W. Swan, Ph.D. Space Elevator Systems Architecture Peter A. Swan, Ph.D. Cathy W. Swan, Ph.D. Space Elevator Systems Architecture Copyright © 2007 by: Peter A. Swan & Cathy W. Swan All rights reserved, including the rights to reproduce this manuscript or portions thereof in any form. Published by Lulu.com [email protected] ISBN 978-1-4303-1405-9 Printed in the United States of America Cover Figure: Space Elevator System by Bradley C. Edwards Title Page Figure: Space Elevator Climber by Bradley C. Edwards TABLE OF CONTENTS TABLE OF CONTENTS ............................................................................... III TABLE OF FIGURES ................................................................................... VII TABLE OF TABLES .......................................................................................IX PREFACE...................................................................................................... XIII CHAPTER I – INTRODUCTION.................................................................. 1 1.0 DREAMS OF MANY ......................................................................................... 1 1.1 WHY BUILD THE SPACE ELEVATOR?..........................................................2 1.1.1 Human Spirit Expansion ............................................................................. 3 1.1.2 Chemical Rocket Engines Have Failed .......................................................... 4 1.1.3 Significant Missions....................................................................................... 5 1.1.4 Expectation vs. Reality................................................................................12 1.2 MEGA-PROJECT COMPARISON ................................................................... 13 1.3 VISION DEVELOPMENT ..................................................................................... 16 1.3.1 Recommended Vision for the Space Elevator............................................. 16 1.3.2 Recommended Vision .................................................................................. 17 1.4 SPACE SYSTEMS APPROACH ........................................................................ 17 1.4.1 Space Systems Architect................................................................................. 17 1.4.2 Space Systems Engineer ............................................................................... 19 1.4.3 Architecture vs. Systems Engineering............................................................ 20 1.4.4 Space Systems Manager ............................................................................... 21 1.4.5 Systems Trade-Off Studies...........................................................................21 1.5 BOOK STRUCTURE........................................................................................ 23 CHAPTER II – SPACE ELEVATOR CONCEPT........................................ 27 2.0 SPACE ELEVATOR HISTORY........................................................................ 27 2.1 SPACE ELEVATOR SYSTEMS CONCEPT...................................................... 31 2.1.1 Phases of the Development............................................................................ 33 2.1.2 Elements of a Space Elevator System ........................................................... 33 2.2 SPACE ELEVATOR MATURITY..................................................................... 35 2.3 SPACE ELEVATOR ISSUES ............................................................................ 39 2.3.1 Selling the Project ........................................................................................ 39 2.3.2 Engineering Aspects....................................................................................40 iii 2.3.3 Testing and Deployment............................................................................... 41 2.3.4 Operations................................................................................................... 41 CHAPTER III – SPACE SYSTEMS ARCHITECTURE VIEW .................. 43 3.1 TOP LEVEL .................................................................................................... 43 3.1.1 Phases of the Space Elevator Development...................................................... 44 3.2 SPACE SYSTEMS ARCHITECTURE PROCESS – ACADEMIC APPROACH ... 45 3.2.1 Creative Process ............................................................................................45 3.2.2 Architect Waterfall...................................................................................... 46 3.3 SPACE SYSTEM ARCHITECTURE PROCESS – PRACTICAL APPROACH..... 48 3.3.1 Support for Architecture Views ..................................................................48 3.3.2 Role of the Architecture Views ..................................................................49 3.3.3 Value of Architecture Views .......................................................................50 3.3.4 Space Architecture Views ............................................................................51 3.4 APPROACH FOR DEVELOPING ARCHITECTURAL VIEWS ........................ 59 3.4.1 Guidelines for Development.......................................................................... 59 3.4.2 Application of Guidelines ............................................................................ 59 3.4.3 Interrelationship of Views............................................................................62 3.4.5 Six Step Process Applied to the Space Elevator............................................63 3.4.6 Architectural Tools......................................................................................70 3.5 SPACE ELEVATOR ARCHITECTURE VIEW-1 (AV-1)................................. 70 3.5.1 AV-1: Overview and Summary Information................................................ 70 CHAPTER IV – SYSTEMS ENGINEERING APPROACH ....................... 87 4.0 SYSTEMS ENGINEERING OVERVIEW......................................................... 87 4.1 SYSTEMS ENGINEERING PROCESS ............................................................. 88 4.2 SYSTEMS ENGINEERING PROCESS TASKS................................................. 90 4.2.1 Tools and Documents...................................................................................92 4.2.2 Responsibilities ............................................................................................ 93 4.3 HIERARCHICAL LEVELS APPROACH .......................................................... 94 4.4 SPACE ELEVATOR SYSTEMS ENGINEERING APPROACH ........................ 96 4.4.1 Comparison................................................................................................. 96 4.4.2 Goal ........................................................................................................... 97 4.4.3 Pragmatic Principles....................................................................................98 4.4.4 Initial Concerns........................................................................................... 98 4.4.6 Requirements Foundation............................................................................99 4.4.6 Systems Engineering V..............................................................................102 4.5 SPACE ELEVATOR MOTIVATION..............................................................103 4.5.1 Vision Development ..................................................................................104 4.5.2 Creating and Maintaining a Vision...........................................................105 4.5.3 Apollo Comparison ...................................................................................107 4.5.4 A Simple Vision.......................................................................................108 4.5.5 Motivation.................................................................................................108 4.6 WRIGHT-FLYER TRADE STUDY SPECTRUM ............................................111 4.7 SYSTEMS ENGINEERING CONCERN.........................................................134 4.8 TRADE-OFF STUDIES..................................................................................137 iv CHAPTER V – SYSTEMS ENGINEERING TRADE: SPACE ELEVATOR SURVIVAL .....................................................................................................139 5.0 INTRODUCTION.......................................................................................... 139 5.1 USER NEEDS – SYSTEM OBJECTIVES....................................................... 140 5.2 ESTABLISH FUNCTIONALITY .................................................................... 141 5.3 ESTABLISH PERFORMANCE REQUIREMENTS.......................................... 141 5.4 EVOLVE DESIGN AND OPERATIONS CONCEPTS................................... 142 5.4.1 Altitude Breakout....................................................................................... 142 5.4.2 Threat Breakout........................................................................................ 144 5.4.3 Survivability Remediation Techniques ....................................................... 147 5.4.4 Systems Approach for Survival................................................................... 152 5.5 SELECT A BASELINE..................................................................................
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