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Spacecraft Design and Sizing . Dr Andrew Ketsdever MAE 5595 Lesson 14. Spacecraft Design and Sizing Sizing Introduction. Big Picture: The Mission drives the Payload and the Orbit, which drives the Spacecraft Design. Spacecraft Design and Sizing Overview of Spacecraft Design & Sizing.
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Spacecraft Design and Sizing Dr Andrew Ketsdever MAE 5595 Lesson 14
Spacecraft Design and SizingSizing Introduction • Big Picture: The Mission drives the Payload and the Orbit, which drives the Spacecraft Design
Spacecraft Design and SizingOverview of Spacecraft Design & Sizing
Spacecraft Design and SizingPrincipal Requirements & Constraints for S/C Design
Spacecraft Design and SizingPrincipal Requirements & Constraints for S/C Design
Spacecraft Design and SizingSpacecraft Configuration Drivers
Spacecraft Design and Sizing • Can use historical data for next block of same S/C, or to generalize within a mission type
Spacecraft Design and SizingMass Distribution for Selected Satellites
Spacecraft Design and SizingMass Distribution for Selected Satellites
Spacecraft Design and SizingTop-Down Sizing Example • Given: navigation mission with mP/L = 50 kg • Find: subsystem masses and mdry
Spacecraft Design and SizingTop-Down Sizing Example • Still need other masses to permit eventual launch vehicle choice • mkick is apogee kick motor – if needed • madapter counts against booster performance #s • Need to include margin
Spacecraft Design and SizingS/C Budgets • For top-down designs, allocate so much of a quantity or capability to each subsystem • Types of budgets • Mass • Power • Communication bandwidth • Volume • Reliability • Pointing error • Cost • Schedule, etc
Spacecraft Design and SizingMass Budget • See previous navigation S/C example • Now add mass margin into calculation • Margin covers the uncertainty in our estimates • Typical range from 5% to 25% • Larger margin for new S/C, or earlier in design phase • Smaller margin for known S/C, or as design progresses
Spacecraft Design and SizingTypical Power Consumption by Module or Subsystem
Spacecraft Design and SizingPropellant Budget • List v’s • Use ideal rocket equation to convert v to propellant mass
Spacecraft Design and SizingEstimating Spacecraft Equipment Compartment Dimensions