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orbits• Oblates, Prolates, J-2 and sun synch• Lagrange Points (stable & un)• GPS: 4 equations, 4 unknowns• Speaking of Oribits:
– Nutation; Precession; Nodes; Line of nodes; Semi-major axis, “The Paramter, P”, Right Ascension, Argument of Perigee, True Anomaly, Vernal Equinox, Inclination, Azimuth/Elevation/Declination, Geoid, Periapsis / Apoapsis, Julian v. Gregorian
• Sidereal day & Geosynch
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Return on Investment
-25000
-20000
-15000
-10000
-5000
0
5000
10000
0 5 10 15 20 25 30 35
Month
Month
Revenue - Investment
(revenue - investment)
Investment Value (with i)
But first, a word from our sponsor: $$$
A large number of small monthly payouts ------
…adds up to a lot of negative equity ------
…and even more with foregone interest included ------
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You Are Here
Design Roadmap
DefineMission
ConceptSolutions &Tradeoffs
ConceptualDesign
Requirements Analysis
OrbitPropulsion
/ ∆VComms
AttitudeDetermine & Control
LaunchGroundStation
Thermal /Structure
Deployables
InfoProcessing
Top Level Design
Iterate Subsystems
Suppliers / Budgets
PartsSpecs
Mass
Power
$
∆V
Link BitsMaterialsFab
Detailed DesignFinal Performance
Specs & Cost
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For next time• Requirements Doc
– Mission Requirements
– System Definition– Begin Tech
Requirements
• Launch Strategy– Primary LV and cost– The last mile
problem
• Reading– Requirements Doc
Sample– Power:
• SMAD 11.4• TLOM 14
– Mechanisms:• SMAD 11.6 (11.6.8 too)• TLOM ?
– Fill in re ACS: TLOM:• Chapt. 6 (magnets)• Chapt. 11 (ACS)
• Thinking– What can you
build?– What can you test?
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Req. # Requirements Crit. Valid. Appr. Source/Comments1. Mission1.1 Piggyback payload insertion orbit shall be dependent on primary payload orbit 3 Review1.2 Primary payload orbit shall not be affected by piggyback orbit
3Demonstration,
Analysis, Review
1.3 Piggyback payload shall be given 0.6 - 1.2 m/s separation velocity relative to the launch vehicle.Velocity vector shall be along payload longitudinal axis
2 Review
Shuttle Hitchhiker is capable of 0.3-1.2 m/s while the ASAP 5 has the maximum velocity (3 m/s) capability. This and CG data will be required for Tip-off and Collision Avoidance Analysis
1.4 Piggyback payload shall be designed for operation without special orientation or spin required atseparation from launch vehicle 2 Review
Some launch vehicles may be able to provide special attitudes and spin at separation, but commonality defines this requirement
1.5 A representative Dummy Payload shall be provided to launch vehicle provider at the beginning ofthe launch campaign
3 Delivery
1.5.1 The dummy payload shall be flight worthy 2 Demonstration1.5.2 The dummy payload shall be representative of the actual piggyback payload in terms of
mechanical interface2 Demonstration
1.5.3 The dummy payload mass shall be within .5 kg of the piggyback payload mass 2 Demonstration1.5.4 The dummy payload shall have the same CG as the actual payload 2 Demonstration1.5.5 The dummy payload shall take the actual payload's place if it is not ready for integration and
launch 3 Delivery
This allows the launch vehicle provider the maximum leeway in launching without the active piggyback payload in case of schedule delays
1.6 Only one person per piggyback payload will be allowed in launch center during launch1 Review
This is only required by Arianespace for ASAP 5. Other launch vehicle providers may be more lenient
1.7 There shall be no standard access to piggyback payload after encapsulation 2 Review1.8 Piggyback payload shall have lifting points for handling and movement of satellite during ground
operations, transport, and encapsulation1 Inspection
2. Schedule2.1 Launch schedule shall be driven by the primary payload and ONLY the primary payload 32.2 Nominal mission start shall be 40 months before launch (T- 40 months) 2 Review On some missions, notably STS, there
might be some leeway2.3 Application for piggyback use on the launchers shall be a minimum of 40 months before launch (T -
40 months)2 Review
2.4 Interface Control Document (ICD) shall be completed for review by launch vehicle provider aminimum of 25 months before launch (T - 25 months)
1 Review See Documentation section for documents that are also due at the same time
2.5 All piggyback payload testing shall be completed as required in the Validation/Testing section aminimum of 7 months before launch (T - 7 months)
2 Review
2.6 Piggyback payload shall be ready for delivery to launcher integration site for integration with launchsystem 6 months before launch (T - 6 months)
3 Review
2.7 Piggyback payload shall be fully tested, fueled and mission ready for integration with primarypayload-launcher combination a minimum of 90 days (T - 90 days) before launch. 3 Inspection
This requirement is driven by STS Hitchhiker. There may be some leeway for piggyback payload provider
2.8 If required, a Structural Integrity Verification Report shall be ready for review by launch provider atleast 13 months before scheduled launch (T - 13 months)
2 Review
This is required of piggyback payloads on Shuttle Hitchhiker. There is some leeway on Shuttle launch schedules, so delays may be negotiated with NASA. This requirement may be ignored on other launchers
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2.0 System Definition2.1 Mission Description2.2 Interface Design
2.2.1 SV-LV Interface2.2.2 SC-Experiments Interface2.2.3 Satellite Operations Center (SOC) Interface
3.0 Requirements3.1 Performance and Mission Requirements3.2 Design and Construction
3.2.1 Structure and Mechanisms3.2.2 Mass Properties3.2.3 Reliability3.2.4 Environmental Conditions
3.2.4.1 Design Load Factors3.2.4.2 SV Frequency Requirements
3.2.5 Electromagnetic Compatibility3.2.6 Contamination Control3.2.7 Telemetry, Tracking, and Commanding
(TT&C) Subsystem3.2.7.1 Frequency Allocation3.2.7.2 Commanding3.2.7.3 Tracking and Ephemeris3.2.7.4 Telemetry3.2.7.5 Contact Availability3.2.7.6 Link Margin and Data Quality
3.2.7.7 Encryption
(Some) STP-Sat Requirements
NB: this is an excerpt of the TOC - the entire doc is (or will be) on the class FTP site
Requirements & Sys Definition go together
Highly structured outline form is clearest and industry standard
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Launch Vehicles
> Review Propulsion and ∆V requirement
> Performance and staging
> Practical Considerations
>Cost & scale observations
>Piggyback vs. dedicated
>Mission $ = 3xLaunch $
>The end is near?
> AeroAstro SPORT
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∆V = gIspln(R)
∆V = ∑i {Vi∆mpi/(M(p))} => V∫{dm/M} (from M=Mo to M=Mbo)