Hardware specific approach Thehardware specific design approach, whichwasadopted, involved modifying theexisting hardware onlyasneeded tocontrol themotion ofthemarman bandassembly tomeetthe requirements. Byminimizing anddelaying rebound effects, aswellastranslating theassembly down andawayfromtheseparation plane, themotion oftheassembly couldeffectively becontrolled. Thereby, satisfying therequirement ofeliminating re-contact withtheseparation plane.Also,since themodifications onlyaffected themarman bandassembly, theywereeasilyadapted toboththe HESandPES.Itwasdetermined thattheboltcutterhousing(s) contributed onlynegative effects to themarman clampassembly actuation. Decoupling themassoftheboltcutterhousing fromthe marman clamps wouldpermittheclamps tofreelyseparate duringactuation andredirect theenergy thatwascausing thecutterhousing toimpact theseparation plane.Itwasdecided thatalinkage couldbeadapted totheexisting loadclamping components oftheassembly allowing theclamps to freelyseparate and,inaddition, support theboltcutterhousing. Inaddition totheincorporation of thelinkage tocontrol themarman clampassembly movement, theexisting retaining springs couldbe redesigned tohavegreater capacity andfunction aspulldownsprings aswell.Byalsoredesigning andrelocating thestopswellbelowtheseparation plane,thesprings couldpullthebanddownand awayduringactuation. Marman BandInterconnect Linkage Thelinkage named the,Marman BandInterconnect Linkage (MaBIL), wasdesigned suchthatit couldusetheexcess energy oftheexpanding clampassembly tomovetheboltcutterradially away fromtheseparation planeandthenwhenfullyextended actasanovercenter latchtominimize rebound. TheMaBIL(Figure 3)replaced theleafsprings asaclampinterconnect feature eliminating thestored energy effectscontributing torebound. Additional benefits ofMaBIL aretherelatively largemassof thelinkscompared tothetotalmarman clampassembly andlinkage jointfriction, bothofwhich contribute totheslowing oftheenergetic separation. Desi_qn Aswithmanyhardware designs, costandschedule arealways ofconcern andthiswasnoexception. Inparticular, schedule wasintheforefront. TheSSPPejection systems wereessentially grounded duetothesafetyconcerns untilthesatellite re-contact issuewasresolved. Itwashighlydesirable to develop asounddesign withaslittleiteration aspossible. Thelinkage configuration thatwasdeveloped consists ofacentral boltcutterclampconnected on eachsidetotheexisting marman clamps through aseriesoftwolinks.Usingtheparametric 3D modeling capability ofProEngineer TMtomodeltheexisting marman clampcomponents anddevelop thenewdesign, itwasmadepossible toassure correct interfacing withtheexisting hardware and avoidinterferences inthenewlydesigned components. Themodeling alsomadeitrelatively easyto assess thelinkage inthepre-deploy (clamped) andpost-deploy (open) condition. Configuring the linkage tocollapse intothesmallvolume available whenthemarman bandassembly wasinthe clamped condition became thestarting pointforthedesign. Itwasessential thatthelinksandbolt cutterclampwereablefoldupwithout interference, providing access totheboltcutters andother components. Onceconfigured intheclosed position thelengthofthelinkswereoptimized inthe expanded configuration tofunction withintheenvelope ofthe50.8-cm (20")diameter canister while providing thegreatest amount ofexpansion fordeployment. Thedetails ofthedesign wereadded tothebasiclinkage configuration. Linkconnections were designed asclevisjointstoassistinloadtransfer andminimize binding effects. Thecompleted design wasstructurally analyzed toprovide positive safetymargins usingfactors ofsafetyof2.0onyieldand 2.6onultimate material strength. Thesefactors ofsafetywereusedinlieuofstructural testing as specified intheHHCarsAccommodations &Requirements Specifications (CARS), 740-SPEC-008, thereby, minimizing testing andreducing costandschedule impact. Theanalysis wasalsousedto optimize component features. Thermal compatibility between linkage component materials andother interfacing components wasrequired toassure thatthemechanism wouldactuate properly atall environmental extremes. Basedonthesefactors corrosion resistant steelsfromtheTableIof"Design Criteria forControlling Stress Corrosion Cracking", MSFC-SPEC-522B, wereselected, 15-5PH condition H1025forthelinksandcutterclamp,andA286hardened toRC30minfortheclevispins. 268