Thevolumerequirements onthespacecraft werelimitinginalldirections. Thespacecraft internal components andexternalelectronics assemblies limitedtheNanoroverandOMREinfivedirections.The spacecraft's stowedsolarpanelslimitedtheNanoroverinthesixthdirectionandincludedalargedynamic envelopeforthespacecraft's solarpanelmotionduringlaunch.Thezerogravityreleaseandseparation oftheNanoroverfromtheMUSESCspacecraftwerethesourceofadditionalfunctionalrequirements. Themostnotablerequirement wasthevelocityoftheNanoroveratseparation hadtobewithinatight toleranceregion.TooslowandtheNanoroverwouldnotbefarenoughfromthespacecrafttobesafe fromtheengineplumes.ToofastandtheNanorovercouldskipoffthesurfaceoftheasteroidandgointo orbit.Theserequirements hadasignificantimpactonthevolumeofthefinalOMREandNanorover designs. TheTemperature Environment Theasteroid fortheMUSES Cmission rotates ataperiod ofabout19hoursandexperiences temperature variations atthesurface from-160°C to+110°C. Thelargetemperature swings atthe surface areafunction oftheamount ofdustcoversthesurface. Itdoesnottakemuchdusttoinsulate the bodyfromtheexternal environment. Thedustalsohasverylittleheatcapacity, resulting inthefull temperature variation inaveryshorttimeframewhenthesurface goesfromdaytonightornighttoday. Thequicktemperature change andthelargetemperature rangeareverysimilarforanysmallbodywitha layerofdust. TheVibration Environment Thevibration environment forlowmassitemscanbeveryharsh.Sincealowmasscomponent likelyhas ahighnatural frequency initsassembly, theresponse toarandom vibration environment canresultin veryhighaccelerations. Forcelimiting duringvibration testing, atechnique thatutilizesthecharacteristic thatitemswillnotrespond tohighfrequency accelerations because theirmassfiltersoutthehigh frequency components, isnotapplicable forlowmassitems.Thetransmitted accelerations thatmanyof theNanorover components responded to,andhadtobestrongenough tohandle, wereabove200g's. Themagnitude oftheNanorover random vibration testenvironment was32g'sRMS.Smallmass systems respond tothehighfrequency components ofthevibration environment aswellastheacoustic portionoftheenvironment. Bothsources ofvibration generate significant loadsonthesmallcomponents thatmakeupasmallmasssystem. Thevibration andacoustic induced loading drovealloftheNanorover component designs. Electronic boardassemblies contain electronic components onthecircuitboards thataresmallandlow mass.Electronic assemblies alsogenerally contain several energydissipative materials intheirdesignto meettheneedsoftheelectrical design. Thissituation results intheelectronic assemblies usually not responding significantly tothehighaccelerations fromvibration oracoustic sources. Mostmoving mechanical assemblies andstructural components donotinherently contain significant amounts of energy dissipative materials. Asaresult,thecomponents andstructure areexposed toveryhigh accelerations inarandom vibration environment. TheNanorover Design Thermal Control fortheNanorover Thethermal controlsystem formostspacecraft usesvarious methods tocontrolthetemperature andthe thermal variations ofregions ofthevehicle wherethermally sensitive components aremounted. The electronics bays,asanexample, areoneareawherethecontrol ofthetemperature isextremely important forthefunctional lifeoftheelectronic components aswellasthethermal cycling lifeofthe electronic packaging. Typical thermal controlmethods employ theuseofthermal blankets, heatsources, heatabsorption devices, thermal conductive pathstogettheheattotherejection surfaces, andradiators torejecttheheattotheexternal environment. NASA/CP--2002-211506 106