Master Thesis - OUFTI-1

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Next year, several tests will have to be performed to validate this model and to verify the exact fulllment of the ESA requirements. Now, the last analysis which must be performed on <strong>OUFTI</strong>-1, concerns random vibrations. 5.5 Random vibration This analysis is based on the characteristics of the LV which is selected. Indeed, this study needs several information about the vibration environment that the satellite has to withstand during launch, and these information are specic to each launcher. For CubeSats, this analysis is generally limited to random vibration. These vibrations are generated by the propulsion system of the launcher and by the vibration-acoustic response of adjacent structures. Maximum excitation levels occured during the principal stage ignition. To characterize these vibrations, each launcher possesses its own PSD. The typical PSDs of several LVs, at qualication level, are given in Figure 5.14. The last version of the Vega PSD is given in Figure 5.15. Figure 5.14: PSD of several LVs at qualication level [60] 117
Figure 5.15: Precise PSD of Vega [57] The model used for this analysis is the same as the one used to perform the modal analysis. To be more accurate, this model would have to integrate the P-POD FE model, to represent accurately the boundary conditions really imposed to the CubeSat during the launch phase. To realize a random vibration analysis, the FE model of the satellite must be excited at the level imposed by the selected launcher. In the case of Vega, for qualication level (which is the most restrictive level), the PSD can be decomposed as follow: • 0.07 g 2 /Hz in the frequency range: [20 − 60 Hz] • From 0.07 g 2 /Hz to 0.1 g 2 /Hz in the frequency range: [60 − 70 Hz] • 0.1 g 2 /Hz in the frequency range: [70 − 200 Hz] • From 0.1 g 2 /Hz to 0.2 g 2 /Hz in the frequency range: [200 − 300 Hz] • 0.2 g 2 /Hz in the frequency range: [200 − 600 Hz] • From 0.2 g 2 /Hz to 0.02 g 2 /Hz in the frequency range: [600 − 2000 Hz] This particular PSD must be introduced in Samcef software through a ".psd" le. Unfortunately, due to a problem encountered with Samcef (which is not yet resolved), this analysis can not be performed this year. However, all the necessary les were created, and information were collected to facilitate the work of the next year's student. 118
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University of Liège Faculty of App
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Abstract OUFTI-1, standing for "Orb
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3.4 Initial idea . . . . . . . . .
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List of Figures 1.1 The Pumpkin's C
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4.18 MAC matrix using the simple me
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List of Acronyms ADCS Al AlNiCo ASI
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Thesis outline This thesis focuses
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of larger satellites. So, the CubeS
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1.2 OUFTI-1 project 1.2.1 Genesis O
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• XatCobeo (Vigo - Spain): Develo
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Chapter 2 OUFTI-1: Flight system co
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Figure 2.2: Product tree of OUFTI-1
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2.3.2 Solar panels The armor panels
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• We do not want to drill or manu
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In our case, because of the limited
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Figure 2.13: Magnetic eld obtained
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Figure 2.17: Pictures of the ADCS c
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consider the possibility of oshorin
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Figure 2.20: Exploded view of OUFTI
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I xx , I yy and I zz are called the
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Subsystem: Structure & Conguration
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Subsystem: Thermal Control Parts Co
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Chapter 3 Design of a new support f
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Figure 3.3: Batteries during and af
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The concept is the following one: F
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A test under vacuum conditions was
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Thermal Expansion (CTE) of the mate
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Figure 3.9: Classication by density
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The last property to determine is t
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• So, it was decided to use two t
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is to prevent the batteries' bulge.
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• Then, the thermostats, that wil
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Figure 3.23: Schematics of the cove
Page 67 and 68: • Other components, including the
Page 69 and 70: 3.9.3 Dynamic behavior Finally, it
Page 71 and 72: 3.10 Summary Through this chapter,
Page 73 and 74: Chapter 4 Electronic cards dynamic
Page 75 and 76: Figure 4.1: Example of manufacturin
Page 77 and 78: Figure 4.4: Illustration of the exp
Page 79 and 80: Figure 4.5: MAC between the two mod
Page 81 and 82: • Global mass/stiness smearing me
Page 83 and 84: 4.2.6 Modeling of the chassis A gen
Page 85 and 86: Q = ω k = 1 ω b − ω a 2 ζ ⇒
Page 87 and 88: Their study was based on the fact t
Page 89 and 90: Figure 4.14: Example of spacecraft
Page 91 and 92: Figure 4.15: Location of measuremen
Page 93 and 94: Figure 4.18: MAC matrix using the s
Page 95 and 96: 4.3.6 Application of the local mass
Page 97 and 98: ρ P C 104 connector = 10.12 × 10
Page 99 and 100: According to this particular shape,
Page 101 and 102: This is due to the fact that this c
Page 103 and 104: environment. Then, this model is ex
Page 105 and 106: 5.2.4 Antenna support For the anten
Page 107 and 108: Components Young's moduli (GP a) Po
Page 109 and 110: Components Young's moduli (GP a) Po
Page 111 and 112: 5.3 Static analysis As described in
Page 113 and 114: Figure 5.9: Illustration of the com
Page 115 and 116: Figure 5.11: Maximal Von Mises stre
Page 117: Figure 5.12: First mode of OUFTI-1
Page 121 and 122: Chapter 6 Conclusions This master t
Page 123 and 124: provided for each method used. We h
Page 125 and 126: last versions of the Verication Con
Page 127 and 128: [13] Ph. LEDENT. "Design and Implem
Page 129 and 130: [40] "Dejond - Aluminum Catalog ".
Page 131 and 132: Appendix A Schemas of solar panels
Page 133 and 134: Appendix B Schemas of electronic ca
Page 135 and 136: Appendix C Fixations of the endless
Page 137 and 138: Appendix D Datasheet of the battery
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Master Thesis - OUFTI-1

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