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George C. Marshdll Space Flight Center Marshail S'dce Flight Center, Ahbnmd https://ntrs.nasa.gov/search.jsp?R=19760019165 2020-03-22T13:53:19+00:00Z NASA TECHNICAL MEMORANDUM NASA TM X-73314 (NASA-TZI-X-73374) TE'IHEXED SUESATELLITE N76-26253 STUDY (NASA) 343 p HC $6.00 CSCL 22A Unclas G3,'15 42351 TETHERED SUB SATELLITE STUDY By William P. Baker, J. A. Dunltin, Zzchary J. Galaboff, Kenneth D. Johnston, Ralph R. Kissel, Mario H. Rheinful'tn, and Mathias P. L. Siebel Science and Engineering March 1976 NASA George C. Marshdll Space Flight Center Marshail S'dce Flight Center, Ahbnmd htSFC - Fcrm 1190 (Rev Junc 1971) TECHNICAL REPORT STANDARD TITLE PAGE i REPOST NO. 72.GOVERNWENT ACCESSICN NO. 3. RECIPIENT'S CATALOG NO. NASA- .. Thl X -73314 -- I 1 TITLE AN0 SUBTITLF 5. REPORT DATE March 1976 Tethered Subsateaite Study 6. PERFORMING ORGANIZATION COOE 7. aUTHOR(S) 8.PERFORMING ORGAN1 ZATION REPOI, T X See Block 15 I 3. PERFORMING CRGAHIIATIOH NAME AND ADDRESS lo. WORK UNIT, NO. - 1 George C. Marshall Space Flight Center 11. CONTRACT OR GRANT NO. Marshall Space Flight Center, Alabama 35812 - .3. TYPE OF REPOR; 8 PERIOD COVERECI 2 SPONSORING AGENCY NAME AND ADDRESS I Technical hlemorandum National Aeronautics and Space Administration Washington, D. C. 20546 1.1. SPONSORING AGENCY COOE I 5. SUPPLEMENTARY NOTES, .-.-9, William p. Baker ,' J. A. Dunkin, Zachary J. ~alaboff,"':: Kenneth D. ~ohnston,'~':'~ Ralph R. Kissel?" Mario H. Rheififurth?:::: and Mathias P. L. ~iebelt Prepared by Space Sciences Laboratoly, Science ard Engineering 6. ABSTRACT This report presents the results of studies performed relating to the feasibility of deploying a subsatellite from the Shuttle by means of a tether. The report addresses the dynamics, the control laws, the aerodynamics, the heating, and sonle cornmumication considerations of the tethered subsatellite system. Nothing was found that prohibits the use of a subsatellite joined to the Shuttle by a long (100 lan) tether. Further, more detailed studies directed at specific applications are recommended. :: Structures and Propulsion Laboratory g::: Electronics and Control 1,nborntorg ::::::::: Systems Dynamics Laboratory Space Sciences Laboratory - - 7. KEY WORDS 18. DISTRIBUTION STATEMENT Unclassified .- Unlilnited - 9 SECURITY CLASSIF. (4this reput)-VLACU.ITISLL (01 th~. P.0) 21. NO. OF PAGES 22. PRICE Unclassified Unclassified 14 4 NTIS -4 ISFC- Form 3191 (Rev December lP11) For S.lle I>y Natioiial reclinical I~~formationService, Sprii~gfield.Virginin 22 151 ACKNOWLEDGMENTS The Tethci-ed Subsatellite Study was perfonlled by a group drawn from Illany disciplines at the Marshall Space Flight Center. The principal restfits of the study are presented by the authors in this report; many others, however, participated in defining the questions to be addressed and in bringing the study to a meaningful conclusion. Appreciation for their participation is ex%ended to the following individuals: J. C. Blair (ED11) J. L. Burch (E~23) F. Ilugg (ED23) C. S. Jones (1'223) In addjtjon, Mr. Rhcinfurtll griltcfully acknowledges the helpful ant! stimulating discussions which he had with Dr. John Glaese on orbital tether dynamics during the conduct of this study. TABLE OF CONTENTS Page I . INTRODUCTION ............................... I1. I)YNAT\IICS ANALYSIS OF A TETIJERED SURSATELI.ITE ... Sr~mrna~y................................. 1nt ~~otlrrc~tion............................... I.aKr.nilgo' s Id:qr~ntioas......................... Coortlinat.~Sysl. cms .......................... Kinc'tic: T<li~~g:.y............................. J. .rlii.rIions of Motio~i .......................... (;CIICI ..I lixcrl 1:orccs .......................... 'l'c?lllc!r Conf-1-01Laws ......................... R(tsr11l-sol Coiiip~~tctrSimulations ................. SIC~rtl y-State I.nlcral Tcll~or1)cflcclion .............. C'oilcliisions ant1 Itcco~n~~~cncI:ilions................ I11 . INVJ~:S'I'I(;I\TION OF A TETI1~;IIEDSI'BSATEI. LI'J'IS CON'I'JIOL LAW ............................... A . 'I'nlllc~r Wi I-(! ............................... 3 No~i~oI:ii:~lI Sailixccl S:11Ili 1s ............ C . i\c~i~otlvn:~~nicalIySI:il)ilizotl Salcllilcs .............. 1 . S:~l(!llilcinl(~~~fct~'r~lc-c \villi Atnrosl~l~cric Mcasu~.c~lionl.s ... 1 . Jtc~fc?rc~iic.c~s................................ TABLE OF CONTENTS (Concluded) Page V . THERMAL STUDIES ............................ V-1 A . Summa;-y ............................... V-1 B . Introduction .............................. V-1 C . Analysis .................................. V-1 D . Results and Graphs ........................... V-2 E . Conclusions ................................ V-4 F . Iiefercnccs ................................ V-il VI . TETHERED SUBSATELLITE COMnllINICATIONS SYSTEM DESIGN ............................... VI-1 A . Summary ................................. VI-1 B . li~t~ocluction................................ VI-1 C . Rlcthod .................................. VI-2 D . Conclusion ................................ VI-3 APPENDIX: COMPUTATIONAL IiOUTINE 1:OIi ELIMINATII<G 'LTNKNO\VN LAGRANGE MULTIPLIERS ............ A-1 LIST OF ILLUSTRATIONS Titlc Coortlinntc systom ............................ Exponential atmosphcre model .................... Exponcnlinl dcploynlent law .'atc of tethcr dcploymcat versus tilnc ................................ Exponential rleploymcnt law .tether lengtl: versus time ..................................... Optimal yo-yo control (out-of- i~!ane motion) .......... Deployment dynamic stability behavior .............. Pitch angle versus time -- equatorial orbit ........... Roll angle versus time -- equatorial orbit ............ In-plane motion (x-z plot) -- eq,uatorial orbit .......... Out-of-plane motion (y-z plot) -- equatorial orbit ....... Equatorial motion (x-~plot) -- equatorial orbit ........ Tether elongation versus time -- equatorial orbit ....... Tether tension versus time -- equatorial orbit ......... Pitch angle versus time -- polar orbit ............... Roll angle versus time -- polar orbit ............... In-plane motion (x-z plot) -- polar orbit ............. LI ST OF ILLUSTRATIONS (Continued) Fig~~re Title Page II.17 . Out-of-plane motion (y-z plot) -- polar orbit .......... 11-50 II.18 . Equatorial motion (x-y plot) -- polar orbit ............ 11-51 II.19 . Tether eloilgation versus time -- polar orbit .......... 11-52 II.20 . Tether tension versus time -- polar orbit ............. 11-53 11.21 . Steacly state nlodal cleflcctions -- 1 aild 2 modes ........ Ii-64 II.22 . Steady state nlodal deflections -- 3 and 4 modes ........ 11-55 11.23 . Steacly state l~~oclaldeflections -- 5 and G modes ........ 11-56 11.24 . Steady state modal deflectioils -- 7 and 8 modes ........ 11-57 II.25 . Steady state modal deflections -- 9 and 10 modes ........ 11-58 III.1 . Deployl~lentand retrieval side view ................ 111-11 m.2 . Retrieval froi~tview ........................... 111-12 111- 3 . Deployment (to 100 lun) ........................ 111-13 III.4 . Retrieval (from 100 Itm) ........................ 111-14 III.5 . Station kccping frolit view ....................... 111-15 1II.G . Station Iteeping front view ....................... 111-1G 111.7 . Reel co~~trolsystem l~loclcdiagram ................. 111-17 111.8 . Flow chart to find I<i. I<, for P = Kt* P .I- I<, TII-18 C .......... 111.9 . Conceplual tncchanization ....................... In-18 Li ST OF ILLUSTRATIONS (Continiredl 1:i XI 11-e Title Paqe 1 4% IV-1. Acrocl\m:imic Sol-c-c conllx)ncnts on tclhr~~.\\ire in <- 1 hvparvclocity, free molcc~tlnrIlo\\? . w-$]i-! -2 Acro(1ynnmic licnting or tctlicr \\.ire at, a - DOo . IV-10 IV--1. Dl-a;:' cocfficicnt or sphcrcs in ol-l)it . N-12 N-9. D1.:1g ccorl'l'ic.icnt (11' sp1icl.c \villi conc-Sri~stum nl'l.crl)ntlg in c11'l)it :IL zero :lnxlc ol' ntt:~c.l.; . IV-17 1-1 1\\-i:11force cocl'l'ic~ic:nl(11' sl)l~rl.c\\,jlh corio-l'~.~~slri~~i ;~fl.c.~~l)ocl\. , . , . , . TV-10 JV-].,I. N:ili~~-nll'~-c,cjtrc~nc.y 01' oscj 1 l:~l.iollof sl)lic~~'c-co~ic-fl.~~slurn strl~s:rlcll ilo as I'unc*tion01' :ilti ltrtlc . Ill-22 LI ST OF I LLU STRATIONS (Continued) Title Page Maximum a111plitucle of spl~e'e-cone-lrustu~lm subsatellitc oscillation as function of initial ang111ar speed disturbance ata=O0 .................................. Maxiil?uill amplil~~cleof oscillation of sphere-cone-fi~~stum subsatellitc as function of altituclo ................. Decay lime for ampliluclc ol oscillation of sp11ci.e-cone- frustuln~su1)satcllitc as function or allitudc ............ Aerorlynamic hcnting for cones. ................... Ec~uilibriumlcmpcmturc of conical allerl~odyat a - 0" ................................... Interfcrolcc or sntcllilc ~vilhalmospl~cric mcaslrrci~ienls . Density, tci~ipcralure,and atomic osjrgen (~nass fraction) profiles on stagnation slrc::imli~~callcad of 1 m clian~clersphere ............................. Acrocly~lamicheatin:; ralc vcrsus allilutlc ............. ~-\erotly~~a:nic.ancl solar l~cal:as ~xrccnlilcsof lots1 cxtcrnal heat ................................ Salcllitc csl.craal tcm)~c~ralurcvc.1-sus allilurlc .......... IIig11 pcrfornlatlcc insulation vcrsus llcal Ira11srcr ralc for spherical tclllc~*cc;s:~tcllite ...................... Ii~tcrnalhcat up rate versus 01-l~ilaltluratiol~ al' 107 Irm for Lcll~crctlsalcllilc ............................. v-ti. LIST OF ILLUSTRATIONS (Concluded) Figure Title Page V.7 . Antenna temperature versus time .................. V-11 V.8 . HRSI (L1900) tile - basic construction .............. V-12 V.9 . Wire temperature versus height ................... V-13 VI.1 . Plasma cutoff frequency
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