EMFFORCEDESIGNDOCUMENT   5/16/2002 TABLEOFCONTENTS 0ProgramOverview 14  0.1Introduction 15   0.1.1Background&Motivation 15  0.2MissionStatement 16  0.3RequirementsSummary 16   0.3.1CustomerRequirements 16   0.3.2FunctionalRequirements 17   0.3.2OperationalRequirements 17  0.4Purpose 18 1SystemOverview 19  1.1Visualization 20   1.1.1Actuation 20   1.1.2FormationFlight 20   1.1.3Electronics 20   1.1.4Structure/Power 21  1.2Flowdown 21   1.2.1InformationFlowdown 21 2Subsystems 22 2.1EM 23 2.1.1SubsystemOverview 23 2.1.2PurposeOfPart 24 2.1.3Interfacing 24 2.1.4TradesAnalysis 24 2.1.4.1CoreMaterial 24 2.1.4.2Configuration 27 2.1.4.3Coreandsystemmass 30 2.1.5ExternalInterfacingNeeds 32 2.1.6Budgets 32 2.1.7Conclusion 32  2.2ReactionWheelAssembly 33 1EMFFORCEDESIGNDOCUMENT   5/16/2002 2.2.1SubsystemOverview 34 2.2.2PurposeofRWA 34 2.2.3RWAInternalInterfacing 34 2.2.4RWATradeAnalysis 35 2.2.4.1ReactionWheelMaterialSelection 35 2.2.4.2ReactionWheelManufacturing 35 2.2.4.3ReactionWheelMassandSizeEstimates 35 2.2.4.4RWAPowerEstimate 38 2.2.5SummaryofReactionWheelSelections 39 2.2.6ExternalInterfacingNeeds 39 2.2.7Budgets 40 2.2.8Conclusion 40 2.3Control 41  2.3.1SubsystemOverview 41  2.3.2SteadyStateMode 42   2.3.2.1DefinitionofSteadyStateMode 42   2.3.2.2DiscussionTradesAnalysis 43   2.3.2.3SummaryofOptions/SelectionCriteria 49  2.3.3Spin-up/Spin-downMode 49   2.3.3.1DefinitionofSpin-up/Spin-down 49   2.3.3.2DiscussionofTradesAnalysis 52   2.3.3.3SummaryofOptions/SelectionCriteria 53  2.3.4ControlArchitecture 53   2.3.4.1DefinitionofControlArchitecture 53   2.3.4.2DiscussionofTradesAnalysis 54   2.3.4.3SummaryofOptions/SelectionCriteria 54  2.3.5ExternalInterfacingNeeds 54  2.3.6Budgets 55  2.3.7Conclusions 55 2.4Metrology 56  2.4.1SubsystemOverview 56 2EMFFORCEDESIGNDOCUMENT   5/16/2002 2.4.2SystemTradeAnalysis 56 2.4.3DesignOverview 57  2.4.3.1Algorithm 58 2.4.4UltrasonicTransmitter 58  2.4.4.1PurposeofPart 58  2.4.4.2DiscussionofTradeAnalysis 59 2.4.5UltrasonicReceiver 59  2.4.5.1PurposeofPart 59  2.4.5.2DiscussionofTradeAnalysis 60 2.4.6InfraredTransmitter 60  2.4.6.1PurposeofPart 60  2.4.6.2DiscussionofTradeAnalysis 60 2.4.7InfraredReceiver 60  2.4.7.1PurposeofPart 60  2.4.7.2DiscussionofTradeAnalysis 60 2.4.8RateGyro 61  2.4.8.1PurposeofPart 61  2.4.8.2DiscussionofTradeAnalysis 61 2.4.9Accelerometer 61  2.4.9.1PurposeofPart 61  2.4.9.2DiscussionofTradeAnalysis 61 2.4.10MetrologyDesignIssues 61 2.4.11ExternalInterfacingNeeds 62  2.4.11.1AvionicsInterfaces 62  2.4.11.2CommunicationsInterface 62  2.4.11.3ControlInterface 63  2.4.11.4PowerInterface 63  2.4.11.5StructuralInterface 64 2.4.12EstimatedBudgets 64 2.4.13Conclusion 64  2.5Communications 66 3EMFFORCEDESIGNDOCUMENT   5/16/2002   2.5.1SubsystemOverview 66   2.5.2Radio-FrequencyTransceiver 67    2.5.2.1PurposeOfPart 67    2.5.2.2PartInteractionwithSubsystem 67    2.5.2.3DiscussionofTradesAnalysis 68    2.5.2.4SummaryOfOptions/SelectionCriteria 69   2.5.3CommunicationSubsystemArchitecture 69    2.5.3.1PurposeOfPart 69    2.5.3.2Partinteractionwithsubsystem 70    2.5.3.3DiscussionofTradesAnalysis 70    2.5.3.4SummaryOfOptions/SelectionCriteria 73   2.5.4ExternalInterfacingNeeds 74   2.5.5Budgets 74   2.5.6Conclusion 75 2.6Avionics 76 2.6.1SubsystemOverview 76 2.6.2On-BoardComputer:Tattletale8 77 2.6.2.1PurposeofPart 77 2.6.2.2PartInteractionwithSubsystem 77 2.6.2.3DiscussionofTradesAnalysis 77 2.6.2.4SummaryofOptions/SelectionCriteria 80 2.6.3SoftwareEnvironmentandCode 81   2.6.3.1PurposeofPart 81 2.6.3.2PartInteractionwithSubsystem 81 2.6.3.3DiscussionofTradesAnalysis 81 2.6.4HardwareSupport:DAC 82  2.6.4.1PurposeofPart 82 