ai-aerospace/ams_data_full_2000-2020 huggingface dataset:
Thecablepulleyandweightsystem wasthefirstonedesigned intoaCADmodel,sinceitwaslesscostly andeasiertobuild.Butmoving theweightsystem required alotofspaceandthedetailed designwork wouldhavetakenalotmorehoursthanthespringmotoroffloading system. Oncethemainstructure and 90°turnsystem designwascompleted, thespringmotoroffloading system cametoourattention andthe designwasquicklyswitched toFigure7. .....---;i:_::--:-- ...._Pl,_,]:N.,SUPPORT ..<.-.-_i:,£C:-_-::::-.......-"" :,-:.TP..Ui-TUTP...E ::'::i:;_;__]il]"__,,--:zPRIN,s HnTnR ';'.,',",:.t,'-':"':.""_,",y.:-....-::<;.< ",=,,,' ?-:.3,,,_- ...-.-.. :-",";',:'[]].-.-:::- '_,--FLI5HTr]:It,IE',,_,L ....:% 2;:-:-_:';:'_';-,'"-,'".... _',"h'::,-'-:2;"[_[_;.;.:"1__ ,_r,',.L----_,_____"Tf-S:..,., '..._:r_.nF I},:",',uW,,'I1",,",_"?._/11_,,::":,;', ;,,_::,,_.:--"-",, ,_  ,,'I_?J"","'P ,:,',,"__:;_.r,.L_--_r',," IB-.N,','"¢.7/_ ";-"-L£'%"',,;_-_ ",,.," :::---'4::,i:.;>..--_...x%<-- [..---.I__.......•"--t--,t-_:--.,_. ......__,:1 .......:......._=;;:.........--%_'_1/ -:-_::::..........._-:;-::-.:..::.::------1< ..............]'',Illlll,_......:_:_t::[1.Ji'--F'EEIE:_':T'_'L "--."- --,. .-- ".-. ..-" -"'--,.° ......---' .°,-- °'°'--_. ° ......-'-"- "-,... ._.-,° - .-- "-°'-._°. °.° °.-.-°" °.-°" "°""°-'---._ I_.---J-" Figure6.Cablepulleyandweight offloading system Figure7.Spring motoroffloading system Themaincomponent ofthespringmotoroffloading system isaconstant-force springmotor.Thedesign ofaconstant-force springmotorreflects thebasicprinciples showninFigure8.Here,onecanseethat theso-called constant-force springhasminimum loading capacity variance whenusedbetween pointsA andBinthegraph.Thenacablewoundontoatapered drumisusedtocompensate theloading capacity variance inordertoachieve constant forceoutputontheloading cable(Ref2.). NASA/CP--2002-211506 346
SPRING LRAO FONSTANT FORCE rPP-.ING_ ._ _ i" \ 7.... ,,I_ ',, z-- RE._UL._RS:PRr,G--..,.,,_/ ......",B...."- A: ,_"_'--- ,,i,.),.. /'/III/ t_I i_I'_I'l]'/' / SPRING OEFLECTI_'4.//° // /o / ://_PRINISNOTOF.'. CABLE LOAO // TESTRESULT o// // °// 4- /"o ;/'-,\/\ "\ x\...\J It • _, _, L_CONSTANT FORCE SPRING HOTOR --REF,IJL.,kRSPRING sYSrEN L SPRING OEFLECT]:_I SPRINGHDTOR CABLELOAD Figure8.Constant-force springmotor Inaddition totheoffloading system, theoverallmechanical designincludes amainsupport structure ona Scientific Atlanta turntable, tosupport theoverall system inthecompact antenna rangeatEMS.The system includes anSGTRC support structure andwave-guides. TheSGANT installation system includes aliftingsetupandatransfer support structure and,ofcourse, safetydevices ofvarious kinds. Offloading system calibration andlessons learned Thecalibration ofthetestsystem setupisshowninFigure9. Usingamassdummy tocalibrate acomplicated flightsystem testsetupcanprotecttheflighthardware; it allowsthesetuptobeverified beforetheflighthardware isinstalled intoit.Themassdummy mustbe representative ofthemassoftheflightsystem. InthecaseoftheSGANT, atthetimethatthemass dummy wasbeingdesigned, theSGANT CADmodeldesignwasunfinished andfullinformation wasnot available. Therefore amassC/Gtuningsystem needed tobeaddedtothesystem. ApartialDesign Verification TestModel(DVTM) gimbalwasfinallyusedtorepresent thegimbal movement andmost importantly, torquesensors wereinstalled intoboththeELandXELgimbalaxestomeasure theoverall system loadintroduced intotheflightSGANT bytheoffloading system (Figure 9). Massdummy desi.qn Themassdummy design isshown inFigure 10.TheC/Gtuningweights needtobesufficient to compensate anydesignchange andmanufacturing error.So,thetuningmasses havetoberelatively largeandhavealargerangeofmotion. Thepurpose ofthetorquemeasurement assembly istoqualifyandmonitor theoveralltestprocess from beginning toend.ThedesignisshowninFigure10,inwhichtorquesensors areinstalled ontheDVTM gimbal. Onesideisinstalled onthemoving portion ofthegimbal andtheotherismounted onthe stationary side.AMicroBreading instrument isconnected tothesensor. Atastress-free condition, the instrument reading shouldbesettozero. NASA/C P--2002-211506 347
[--0vrt,i13IHBAL TBE:BUEHEA,SUE:EHEN-i :S:UElA:S:Z:EHE',L? Figure9.Calibration setup Figure10.Massdummy design SGAGTestFixture Calibration Report Thetablebelowliststhemaximum torque loadontheDVTM gimbal during horizontal lifting operation: Max.loadallowance Max.loadrecorded* XELGimbal 27.11N-m(240Ibf-in) -2.711N-m(-24Ibf-in) ELGimbal 27.11N-m(240Ibf-in) 1.8N-m(16Ibf-in) 2.Maximum torque loadontheDVTM gimbals during transfer between thehorizontal lifting configuration andrestonthetemporary support structure: Max.loadallowance Max.loadrecorded* XELGimbal 27.11N-m(240Ibf-in) 1.8N-m(16Ibf-in) ELGimbal 27.11N-m(240Ibf-in) 30.05N-m(266Ibf-in)** NASA/CP--2002-211506 348
.Maximum torqueloadontheDVTMgimbalwhenthedummy massisinstalled ontheSGAGtest fixture(whenELGimbal isatthe0°testconfiguration): Max.loadallowance Max.loadrecorded* XELGimbal 27.11N-m(240Ibf-in) 8.7N-m(77Ibf-in) ELGimbal 27.11N-m(240Ibf-in) 10.06N-m(89Ibf-in) ,Maximum torquerequired todrivethegimbalwithin+5°whentheELgimbal isatthe0°test configuration: Max.loadallowance Max.loadrecorded* XELGimbal 27.11N-m(240Ibf-in) 9.38N-m(83Ibf-in) ELGimbal 27.11N-m(240Ibf-in) 7.63N-m(67.5Ibf-in) ,Maximum torqueloadontheDVTMgimbalwhentransferring thedummy massfromthe0°tothe 90°configuration: Max.loadallowance Max.loadrecorded* XELGimbal 27.11N-m(240Ibf-in) 0.8N-m(7Ibf-in) ELGimbal 27.11N-m(240Ibf-in) 0.34N-m(3Ibf-in) ,Maximum torquerequired todrivethegimbal within+5°whentheELgimbal isatthe90°test configuration: Max.loadallowance Max.loadrecorded* XELGimbal 27.11N-m(240Ibf-in) 9.38N-m(83Ibf-in) ELGimbal 27.11N-m(240Ibf-in) 7.64N-m(67.5Ibf-in) Maximum loadsdetermined bydummy loadmeasurement. Locking pinengaged, loadacceptable. Basedonthecalibration report,onecanobserve thatduringthehoistandtransfer operation, alarge unexpected torqueloadwasintroduced intotheflightgimbals, whichisoverthemaximum loadlimit.It wasconsidered apotentially fatalloadtotheflightgimbals. Theseoperations wererepeated several timestofindoutthereason. Theoperator wasinstructed toreduce thehoistspeedtotheminimum. However therecorded loadswereunpredictable, between 22.5N-m(200in-lb)and56.5N-m(500in-lb). Finally, twogimballockpins9.53-mm diameter (3/8"dia.)wereinstalled intotheflightgimbals, especially forthehoistandtransfer operation. Without thecalibration exercise theflightgimbals couldhavebeen destroyed duringthetest. NASA/CP--2002-211506 349
Lessons Learned Foramultiple gimbalmechanism, thegimbals mustbelockedfortransfer andhoistliftingoperations. DefinetheIoadinq point SincethefrontoftheRIRS(apartoftheSGANT) provides someMGSEholesforatoolinginterface, and thecalculation showed thattheyareveryclosetotheidealoffloading point,itwasdecided todirectly hookupfromtheMGSEholeswithabracket, asolution thatwasintheoriginal design. Itisillustrated in thecalibration setupinFigure9. Thefirstcalibration showed thatdrivingaboutonly2degrees offfromthestarting point,apotentially fatal loadwasintroduced intotheXELgimbal. Aquickanalysis onthemassmodelisshowninFigure11, whereonecanseethatforceF2increases rapidlywhentheXELgimbalstartstomove. Aftermodification, theliftingpointwasmovedtotheposition showninFigure11.Themechanism usedto movetheliftingpointisshown inFigure9.Theloadintroduced intotheXELgimbalisnowextremely small,withinits5degrees drivingrange,andisbarelydetectable. F1.........................LifFt..ri,-,°rig0t:tPF'.%:Urc,Iin.F.'.:-:t:to,'-e I-,r--fnr--r:z,-QIiI-rclkiI-I1-1 F> -/5 ,/" i1' /' iI ,,,' iiiiiIIII ,1111'11.1'11 ""TI _!-O ............. E:<:' Ill --------'-' '" .......-,'1',- .........I/",,,LIft:,.In!:1F',:,In.b ".... "--t,::,t,sI,:_ss',/,'t/ei,::]ht after,_,:,.lil-,ro+..i on/ t,:).L,elifbe,.tL:,:/'- E'=254r_r-l':: 10"'1:,!_- _-- ,_,l-l-I,_,ud_r #1,::10.:.'Ihs::, Figure11.Liftingpointselection mistake Lesson learned: Todefinetheoffloading point,simplylininguptheoffloading pointtotheC/Gisnotenough. Theselection shouldbebasedontheanalysis onall3dimensional locations togetthebestoffloading results. Movinq theSGANT between EL=°/XEL=0 °,andEL=90°/XEL=0 ° Inrequirement 4itisstatedthatthetestsystem mustprovide a+5°motionfortwoSGANT positions, namely EL=°/XEL=0 °,andEL=90°/XEL=0 °.RefertoFigure6andFigure7. NASA/CP--2002-211506 350
Toturntheantennasystemonthetestsetupfromthe0°tothe90°testingposition,logicallythetelemetry fromthegimbalsdrivingsystemshouldbeused.Usingthistelemetrytosynchronize theoffloading systemdriveinorderforthegimbalandtheoffloadertomovefromonepositiontoanother.Todoso,a servosystemisrequired.However,fortheSGANTtheservosystemwaseliminatedasacost-saving measure.Itwasdecidedtouseanoperatortocrankthegearboxandsynchronize thedrivemanually. Letusseetheresults. Theproblemstartedinthecalibrationphase.Thesynchronized driveoftheoverallsystemwasalmost impossible tocontrolmanually.Twotechnicians hadtobetrainedforaweekonthemassdummyto performthetransferdrive.Inaddition,afivedegreeswarninglimitswitchhadtobeaddedtothesystem. Duringthetransfer,whenevertheflightgimbalandtheoffloaderhadanangulardifferenceof5degrees ormore,thealarmswitchwentonandtheoperatorhadtoadjusttheoffloaderposition.Inthemeantime, thepowerwentoff,andthesystemhadtoberestarted.Itbecamethemosttime-consuming operationof theSGANTgroupleveltestphase.Thetotalcostinhourswasmuchmorethanaservodrivingsystem. Sincetheoperatorhadtoclimbuptothetopofthemainstructureabout15metershigh,safetyalso becameanissue. Lesson learned: Synchronizing thedriveoftwomechanical systems manually isaverydifficulty task.Depending onthe accuracy required aservomechanism shouldbeusedtoautomate thetaskandobtainaproperresult. Figure12showsthesystem afterfinalcalibration andmodification. Conclusion Themethod finallyusedtooffload theSGANT two-axis gimbaled system withtwosynchronized offloading systems hasbeenproventobecorrect. Thetorqueloadintroduced intothesystem iskeptwell belowacceptable limits.Themethods usedinthiscasecanbedeveloped andusedtodesignothermultigimbalsystem offloading mechanisms. Calibrating thesystem usingamassdummy torepresent theflight hardware andinstalling thenecessary instruments tomeasure torqueloading isanefficient method to helpprevent thepossibility ofdamage toflighthardware. Acknowledgements Theauthorwouldliketothankhiscolleagues Graham ArberyandPeterRichter fortheirtechnical advice ontheproject andforproofreading thispapertomakeitreadyforpublication. Thanks alsoduetoMs. PauleMercier &Catherine YiZhangfortheirsincere effortineditingthispaper. References 1.Arbery, Graham, SGSControl system ground testrequirements specification, p12,1995,EMS Technologies 2.Caravaggio, Levino, Largeitemoffloading, 31March1992SparAerospace Ltd. 3.Zhang,Xilin,ISSAMGSEuser'smanual 199814April.EMSTechnologies. NASA/CP--2002-211506 351
[11]JinMitsugi,DirectCoordinate Partitioning forMultibodyDynamicsBasedonFiniteElementMethod, Proceedings of36thStructuresStructuralDynamicsandMaterialConference, AIAA-95-1442-CP, May 1995,pp.2481-2487. [12]JinMitsugi,YumiSenbokuya, DynamicAnalysisofCable-Driven FlexibleMultibodySystemsandIt's Experimental Verification, 37thStructuresStructuralDynamicsandMaterialConference, AIAA-96-1484, May,1996. [13]HironoriIshikawa,KazuhideAndo,TheEffectoftheSynchronization ErrorsintheDeployment Motors ofaModularMeshAntenna,Proceedings of22ndInternational Symposium onSpaceTechnology and Science,vol.2,2000,PP.1541-1546. [14]MitsunobuWatanabe, JinMitsugi,AkihiroMiyasaka,MasashiShimizu,largeSpaceAntennaStructural DesignTechnology Status,49thInternational Astronautical Congress,IAF-98-1.1.01, 1998. [15]JinMitsugi,TetsuoYasaka,AModularApproachtoBuildaLargeSpaceAntenna,Proceedings of42nd CongressoftheInternational Astronautical Federation, IAF-91-315, October5-11,1991. NASA/CP--2002-211506 358
Table1.Relations amongthedifficulty indexvalue,theweight, andthespringforce Difficulty indexvalue Weight (kg)Springforce(N) 1 0 8.2 26 0.5 6.3 45 1.0 6.3 84 2.0 6.3 122 3.0 6.3 160 4.0 6.3 415 4.2 2.5 606 6.2 2.5 845 8.6 2.5 Table2.Weightoftheribstructure inexperimental andanalysis models Measurement pointWeight (kg) Actualmodel Analysis model Left 0.222 0.202 Right 0.135 0.115 IE+06 IE+05 1E+04 •-"IE+03 1E+02 °,,-_ IN+01 IE+00Unfurlable_n_na. q""'-.TVlo_.d.u]armesh   -- oopcolumnI "° 1D /_-p_.-!g .i_'O-'V-SOP_--d=_l-.0m JO .°" •'d=2.0m 5 i0 15 Antenna diameter(m)20 25q Figure1.Difficulty indexvalue NASA/CP--2002-211506 359
0.6m 0.6m 4-  ]JI)_beam _de beam(  --@ Diagonal beam  _'__:_ Lowerbeam  Plate(B_ Constant C)Stand Ribstructure03m )_0.15m Motor forcespring •Rolaional hinge Figure2.Planartruss Figure3.Microgravitytestingsetup Figure4.Ground testingsetup NASA/CP--2002-211506 360
--Analysis model Suspension system  forck lGravity True value-- eployment driveforce easured bymicro ravitytestingIComparison --Test result------ Deployment driveforce measured bygroundtesting Figure5.Analysis model C.) a = E ©11 10,_./_..^ _,Experiment ....,,_,._., fl,A , ...........: i i i 0 0s2 0_4 0_)G 0_8 Deploy _slidelength(m) _Stow Figure6.Difference between experimental andanalysis results (DIV=1) NASA/C P--2002-211506 361
O.O15m Gravity directionHorizontal direction Figure7.Position ofthepulleyandthesuspension cable 10 ¢) <_95 ;> .-- 9 t" e-. © {::x.8s¢)Newmodel (revised suspension - counterweight )position and o o_2 o_4 o_6 o_8 Deploy _slidelength(m) _Stow Figure8.Influence oftheerrorinsuspension position andthecounter weight NASA/CP--2002-211506 362
11 10 E8 E ©7 C_ 6/Newmodel (revised centerof_ Experiment 1<Normal model 0 0_2 0_4 0_6 0_8 Deploy _slidelength(m) _Stow Figure9.Influence oftheerrorinthecenterofgravityoftheplanartruss Analysis model Suspension system Suspension position Counter weight Line(A) "_Line(B) Gravity Evaluation error F-True value------ __1 Deployment driveforce Imeasured bymicro gravitytestingDm_ePa Testresult-----"  Ioyment driveforce suredbyground testing, Figure10.Procedure ofcalculating theevaluation errorofthegroundtesting NASA/CP--2002-211506 363
S0 40 .......O tO '-30 ....$.. © 20................  O> m._o%ooI0 ....... OO 0 ............. 0ioo 200 300 400 soo _00 Difficulty indexvalue700 800 900 Figure11.Relationship between DIVandtheevaluation erroroftheground testing 11 ...........mDmexpe_J_et- _Fllctlia4n •J i  1IVre .........,DDmBest Fi_ AJ I.'xi[[_'_,.DDFar_sJs 9............ E ..................... © 5................... o oD2 0D4 0D6 Deploy _ slidelength(m) _Stow ..0D8 Figure 12.Deployment driveforceobtained bytheground testing andanalysis (DIV=160) NASA/CP--2002-211506 364
150 R:Oli+13B • • 0o00 0 0 200 400 600 800 i000 Difficulty indexvalue Figure13.Relationship between DIVandtheevaluation erroroftheground testing including fluctuation 18mModule _,. 4.8m ._ I.":'..-.:'""'<---',x,,,"..,:".-,:". _ _/7<_?_;,,,.?<,;:_lVles hsurface 0.6m Deployable truss structure Modular meshantennaModule composition Figure14.Modular meshantenna NASA/C P--2002-211506 365
Deployed configuration Rtib_ucture_Stowed configuration Coilspring Lowerbeam j_ll_Slide ,_' _:_ spring Side_eam // '/' < _ beam  Uppermember Diagonal beam Synchronous beam Figure15.Moduleconstruction 200 150 ; e _-lO0 5 _2 > 5oy ............... 1module 0 0 200 400 600 800 I000 1200 Difficulty indexvalue1400 Figure16.Evaluation errorofthegroundtestingofmodular meshantenna NASA/CP--2002-211506 366
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44th Aerospace Mechanisms SymposiumNASA/CP—2018-219887 May 2018Edward A. Boesiger, Compiler Lockheed Martin Space Systems Company, Sunnyvale, California National Aeronautics and Space Administration Glenn Research Center Cleveland, Ohio 44135Proceedings of a conference held at Hilton Cleveland Downtown Hosted by NASA Glenn Research Center and Lockheed Martin Space Systems CompanySponsored and organized by Mechanisms Education AssociationCleveland, OhioMay 16–18, 2018
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PREFACE   The Aerospace Mechanisms Symposium (AMS) provides a unique forum for those active  in the design, production, and use of aeros pace mechanisms. A major focus is the  reporting of problems and solutions associ ated with the develop ment and flight  certification of new mechanisms. Sponsored and organized by the Mechanisms  Education Association, responsibility for hosting the AMS is shared by the National  Aeronautics and Space Administration and Lock heed Martin Space. Now in its 44th  symposium, the AMS continues to be well attended, attracting participants from both the  United States and abroad.   The 44th AMS was held in Cleveland, Ohio, from May 16 to 18, 2018. During these  3 days, 45 papers were presented. Topics in cluded payload and positioning mechanisms,  components such as hinges and motors, C ubeSats, tribology, docking systems, and  mechanism testing. Hardware displays duri ng the supplier exhibit gave attendees an  opportunity to meet with developers of cu rrent and future mechanism components.   The high quality of this symposium is a result of the work of many people, and their efforts  are gratefully acknowledged. This extends to the voluntary memb ers of the symposium  organizing committee repres enting the eight NASA field cent ers, Lockheed Martin Space,  and the European Space Agency. Appreciation is also ext ended to the session chairs,  the authors, and particularly t he personnel at Glenn Research Center responsible for the  symposium arrangements and the publication of  these proceedings. A sincere thank you  also goes to the symposium executive committ ee who is responsible for the year-to-year  management of the AMS, incl uding paper processing and prepar ation of the program.    The use of trade names of manufacturers in th is publication does not constitute an official  endorsement of such products or  manufacturers, either expr essed or implied, by the  National Aeronautics and Space Administration.  NASA/CP—2018-219887 iii
Enhanced Vi bration Isolati on Using a Magnetic Linear Gear for Highly Demanding   Aerospace Applications .......................................................................................................................... 177  José Luis Perez-Diaz, Ignacio Valiente-Blanco, Juan Sanchez García-Casarrubios,   Cristian Cristache, Fernando Rodriguez-Celis, Judit Esnoz-Larraya,   Efrén Diez-Jimenez & José Luis Perez-Alamo  A Mechanisms Perspective on Microvibration – Good Practices and Lessons Learned ...................... 191  Geert Smet & Sandro Patti  Investigation of Bolt Preload Relaxation for JWST Thermal Heat Strap Assembly  Joints with Aluminum-1 100 and Indium  Gaskets .................................................................................. . 205  Andrew Bartoszyk, Thomas Walsh, Jody  Davis, Jason Krom, Patrick Williams,   Jason Hylan & Edgar Hemminger   Validation and Test Results of the 2.5D Technology for Pancake Slip Rings ....................................... 211  Mélanie Henry & Sandro Liberatoscioli  Quantifying Threaded Fastener Locking ......................................................................................... ....... 217  Daniel P. Hess & Christopher DellaCorte  Reliability Calculation Methodologies for Mechanisms and Actuators .................................................. 223  Tanner Horne & Evan Harrington  Development of the NEA Mini for Low Load Appl ications  ..................................................................... 233   John Sudick & Geoff Kaczynski  Compliant Mechanisms Re-Design based on Additive Manufacturing and Topology Optimization ...... 239  Lionel Kiener, Hervé Saudan, Gérald Perruchoud & Johan Kruis  Non-Pyrotechnic Multi-Point Release Me chanisms for Spacecraft Release ......................................... 247  Ambrosio Mejia, John Sudick & Geoff Kaczynski  Validation of a Novel High Performanc e Magnetic Gearbox for Space ................................................. 255  Ignacio Valiente-Blanco, Judit Esnoz-Larraya, Efrén Diez-Jimenez,  Juan Sanchez García-Casarrubios, Cristi an Cristache, Fernando Rodriguez-Celis &  José Luis Perez-Diaz  Qualification of a Networked Pyrotechnic Initiation System for the CST-100 Starliner Spacecraft ....... 263  David Novotney, Craig Boucher, Joseph Smith, Robert Morlath & Hervens Beauge  Use and Advantages of Direct-Drive  Brushless DC Actuators for Precision Instrument Pointing  of the Total and Spectral So lar Irradiance  Sensor ............................................................................. .... 269  Patrick Brown, Andrew Engelmann & Ryan Lewis  Testing and Maturing a Mass Translating Mechanism for a Deep Space CubeSat .............................. 283  Alex Few, Tiffany Lockett, Richard Wilson, David Boling & Erik Loper  Solar Array Drive Assembly Qua lification Lessons Learned ................................................................. 293  Jonathan Wood & Timothy Pargett  Determining Root Causes of Mysterious Hardware Failures using High Resolution CT Scanning ....... 307  Michael R. Johnson  NASA/CP—2018-219887 vi