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MASTER's THESIS Re-Use of Exomars Rover on Icy Moons of Jupiter

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MASTER's THESIS Re-Use of Exomars Rover on Icy Moons of Jupiter 2010:051 MASTER'S THESIS Re-use of Exomars Rover on Icy Moons of Jupiter Abrar-Ul-Haq Khan Baluch Luleå University of Technology Master Thesis, Continuation Courses Space Science and Technology Department of Space Science, Kiruna 2010:051 - ISSN: 1653-0187 - ISRN: LTU-PB-EX--10/051--SE CRANFIELD UNIVERSITY ABRAR-UL-HAQ KHAN BALUCH RE-USE OF EXOMARS ROVER ON ICY MOONS OF JUPITER SCHOOL OF ENGINEERING Astronautics and Space Engineering (SpaceMaster) MSc THESIS Academic year: 2009-10 CRANFIELD UNIVERSITY SCHOOL OF ENGINEERING Astronautics and Space Engineering (SpaceMaster) MSc THESIS Academic Year 2009-2010 ABRAR-UL-HAQ KHAN BALUCH RE-USE OF EXOMARS ROVER ON ICY MOONS OF JUPITER Supervisor: Dr J. Kingston June 2010 This thesis is submitted in partial (45%) fulfilment of the requirements for the degree of Master of Science © Cranfield University 2010. All rights reserved. No part of this publication may be reproduced without the written permission of the copyright owner. Abstract The ExoMars Rover, developed by EADS Astrium to perform in-situ investigations into the potential existence of life on Mars, may also be exploited for use on other planetary bodies. The Icy Moons of Jupiter (JIMs): Europa, Ganymede and Callisto, are in particular also of key interest to astrobiologists and geologists. The purpose of this research was to perform a feasibility analysis on the operation of the ExoMars rover on these Icy Moons. Specifically, this involved the conduction of design/concept study to determine whether it is possible from a thermal and system power point of view with the current design and, if not, what modifications would need to be implemented for successful operation. The European Space Agency standard tool ESATAN-TMS was employed to perform a detailed thermal analysis. Initially the original model as provided by EADS Astrium-UK was simulated in the extreme environment of Jupiter’s icy moons. On the basis of findings, it was determined that alterations were necessary to the passive thermal control and power sub-system. The rover model was updated and then again placed in the environments of icy moons to be analysed over five scenarios encompassing: equatorial and polar regions of both Europa and Ganymede and on equator of Callisto. The results of these missions were post-processed in the advance post processing tool Thermal NV. It was found that major design changes were required as the original rover failed completely to work on JIMs. Key changes implemented were; the reduction of radiator areas, replacement of solar arrays with Multi Mission Radioisotopes Thermoelectric Generators and their accessories. The structural temperature was also found not to compatible with moon’s surface and a redesign of this element is recommended; however, altering the structural design was beyond the scope of this thesis. From the analysis of all defined scenarios, it was concluded that the rover need major changes in structure, power subsystem and slight changes in radiators sizing, Of key significant, however, was the finding that if the modified rover is made suitable for one moon, then it would be able to operate in the environments of all three icy moons. Consequently, it is feasible that following these design changes that the ExoMars rover concept could be employed for the exploration of JIMs, which would have significant scientific value over a range of science missions, findings of life and other geological investigations. i Acknowledgements All praise to Almighty Allah who bestowed upon me the capabilities and passions to complete this work. My sincerest thanks are due to my supervisor Dr. Jennifer Kingston for her valuable guidance, affirmative criticism, motivations and incredible encouragements. I want to say my thanks to SpaceMaster consortium for giving me this opportunity to study in Europe in the field of Space science and technology. My extended thanks are due to my friends Zhao Lei, Cheng and Karolina for their support, their critique, their help and their encouragement during days of working and anxiety. I also want to say thanks to Charlotte for her guidance and support regarding ESATAN-TMS. Finally, I am grateful to all of my family members who always supported me with love & pray for my success. I can’t forget the special attention of my father (Late) who always prayed for my triumph. It is all his encouragements and support, which made me able to reach at this stage. ii A.H.Baluch Contents Abstract.............................................................................................................................. i Acknowledgements .......................................................................................................... ii Contents........................................................................................................................... iii List of Figures.................................................................................................................. vi List of Tables................................................................................................................. viii Nomenclature................................................................................................................... ix 1 Introduction .............................................................................................................. 1 1.1 Why Icy moons of Jupiter.................................................................................. 2 1.2 Why Rover......................................................................................................... 2 1.3 Aims................................................................................................................... 3 1.4 Objectives .......................................................................................................... 4 1.5 Summary............................................................................................................ 4 1.6 Thesis layout ...................................................................................................... 4 2 Literature Review ..................................................................................................... 6 2.1 Heat transfer Modes........................................................................................... 6 2.1.1 Radiation..................................................................................................... 6 2.1.2 Conduction ................................................................................................. 6 2.1.3 Convection.................................................................................................. 7 2.2 Thermal Control System.................................................................................... 7 2.2.1 Passive Thermal Control (PTC) ................................................................. 8 2.2.2 Active thermal control (ATC) .................................................................. 12 2.3 Temperature limits and margins by ESA......................................................... 13 2.4 Power requirement by Spacecraft .................................................................... 14 2.4.1 Radioisotope Thermoelectric Generators (RTGs).................................... 15 2.5 Jupiter and Jupiter’s Icy Moons....................................................................... 18 2.5.1 Europa....................................................................................................... 20 2.5.2 Ganymede................................................................................................. 21 2.5.3 Callisto...................................................................................................... 22 2.6 Rovers and their history................................................................................... 23 3 ESATAN-TMS designing ...................................................................................... 25 3.1.1 Geometry .................................................................................................. 26 iii A.H.Baluch 3.1.2 Nodes and their types in ESATAN-TMS................................................. 27 3.1.3 Geometric mathematical model (GMM) .................................................. 27 3.1.4 Radiative Case .......................................................................................... 28 3.1.5 Matrix Method (MM)............................................................................... 28 3.1.6 Monte Carlo Ray tracing (MCRT) ........................................................... 28 3.1.7 Thermal mathematical model (TMM)...................................................... 29 3.1.8 Analysis Case ........................................................................................... 30 3.2 A few points worth mentioning for beginners in ESATAN-TMS................... 30 3.3 MORTRAN (FORTRAN-77).......................................................................... 31 3.4 Post processing with Thermal-NV................................................................... 31 4 Modification of Rover w.r.t JIMs........................................................................... 34 4.1 Why Modifications are required ...................................................................... 36 4.1.1 Mission Scenarios..................................................................................... 36 4.1.2 Original ExoMars rover at equator on Europa ........................................
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