Small Satellite Utility: Present and Future

Transcription

1 Session #2: Small Satellite Key Technologies for Remote Sensing Aaron Q. Rogers November 21st, 2007 Small Satellite Utility: Present and Future

2 Acknowledgements Slide 2

3 Agenda Background Small Satellite Utility Studies Focus Areas Obstacles vs. Enablers Good Enough Definitions Conclusions Mid-Term Key Technology Enablers Aperture Drivers Power Systems Ground Operations Common Spacecraft Platforms and Standards Current NASA Study Effort Summary & Hand-Off GISTDA THEOS Slide 3

4 APL Overview Not-for-profit DoD chartered University Affiliated Research Center, a UARC Founded in 1942 Staffing: 4,000+ employees (70% scientists & engineers) Space Department ~ 600 staff Business areas: Air & Missile Defense Biomedicine Civilian Space Homeland Protection Infocentric Operations National Security Space Precision Engagement Science & Technology Strategic Systems Undersea Warfare Warfare Analysis Successfully designed, built, and operated > 64 spacecraft and 200 instruments Slide 4

5 EO Remote Sensing En Route to Mercury Slide 5

6 Small Satellite Studies Government Industry APL Concept Development Problem Definition System Concept Critical Technology Identification Demo., Validation, Prototyping Requirements Definition System Design Requirements Design Development with Government & Industry Technical Evaluation Coord. of Integration Testing Production & Deployment Transition of Prototype Design Follow-on Review and Requirements Utility Assessment Adjust TTPs System Engineering JHU/APL engaged in a number of industry, government, academia studies Reviewed/analyzed features and elements of small satellite systems: Obstacles vs. Enablers Required vs. Good Enough Capability Program Lifecycle Utility vs. Disruptability Technology Enablers Ground Systems and CONOPS Slide 6

7 Obstacles vs. Enablers Obstacles: Funding (always!) Planning Useful Missions Launch Access Operations Enablers: New Commercial Launch Providers, Classes o Examples: Space-X Falcon 1/9 and ISRO PSLV-C8 o Secondary and multi-payload adapters: Falconclass RideShare Adapter (RSA) New spacecraft subsystem technologies o Low(er) cost o Reduced mass, volume, power o Good enough parameters New design tools and methods for small satellites Slide 7

8 Good Enough Utility assessment of small satellites depends critically on establishing what is good enough Small satellites satisfy different portions of access-persistence-quality trade space than exquisite systems Mixed architectures (small/large) can provide flexibility to match needs Other design variables can be relaxed o Performance o Reliability: Shorter (advertised) lifetime, MTBF o Radiation tolerance Demand for small sat solutions necessary to drive many elements of operational responsiveness Inadequate attention given to ground systems, CONOPS, and tasking, processing, exploitation & dissemination Satellites get the attention Current infrastructure development and upgrades focused on large satellites Slide 8 Courtesy MIT/LL

9 Small Satellite Working Definition Mature & Exquisite Systems 5000 kg IRS P6 Yaogan-2 Cosmo-Skymed 1 Large OpSats Accepted/ Proven 1000 kg Demo & Emerging Systems QuickBird-2 KOMPSAT-2 SAR-Lupe 1-5 FormoSat-2 Small/ Mini Sats 200 kg Science & Technology Class Beijing-1 TopSat Lapan-Tubsat RapidEye 1-5 Micro Sats Debated/ Emerging 50 kg Tiungsat-1 Maroc-Tubsat Thai-Phutt Nano Sats UTILITY Experiment & University Class 5 kg ION2 CP4 QuakeSat Cube Sats Hidden 1 kg Slide 9

10 Current Satellite Cycle Contrasts Slide 10

11 Mission Utility Study Conclusions Small satellites have clear utility for: EO Remote Sensing, Space Weather, Technology and CONOPs demonstrators Simple ground infrastructure Smaller apertures, lower power LEO Small sats provide minimal near-term utility for: PNT, Wide-bandwidth communications, Radar Compatibility with large numbers of ground terminals Higher power, larger apertures Continuous coverage, MEO/GEO Slide 11 Courtesy MIT/LL

12 Mid-Term Key Technology Enablers Increase access/persistency, reduce constellation size by going to higher altitude Aperture: Low-mass large optics and antennas, coherent combination of small apertures Power: Mass-efficient solar power conversion & storage Radiation: Rad-tolerant sensors & electronics Improve achievable small sat performance Sensors: Large arrays, reconfigurable sensors Processing: Capable onboard processors Bus: Low-mass structure & stabilization Innovate C3 for constellations Ground Systems: Automated processing and product distribution Operations: On-board autonomy; tool-aided rapid ground system composition Communications: Standard space network USB-style plug Slide 12

13 Aperture Drivers Low-Mass Optics Folded Optics Coherent Combo of Small (Sparse) Apertures Low-Mass Antennas Courtesy QinetiQ Traditional Compound Lens Folded Optic Courtesy Univ. of Rochester Courtesy UC San Diego Slide 13

14 Power Systems High efficiency cell technology State of industry vs. theoretical Thin-film photovoltaics (TF-PV) State of industry and near-term projections Key properties Applications TacSat-2: FITS DSX: PowerSail TacSat-2 Courtesy MSI Courtesy Lockheed Martin DSX Courtesy AFRL Slide 14

15 Ground Operations Distributed and virtual operations centers: Federated ground network Standardized commanding: XTCE What Why How Autonomous commanding and data/tt&c Internet Mission Control Center Satellite Factory Mission Ground System Common Formats Facilitate Transition to Operations and Data Exchange Mission Ground System Courtesy SSTL Network Infrastructure Slide 15 Courtesy SSDL Courtesy NRL

16 Why Build A Common Platform? The availability of a common platform will improve the speed of acquisition, and enable a faster response to changing needs Using a common platform eliminates Non-Recurring Engineering (NRE) Expenses of subsequent vehicles, by performing the engineering and design only once for a large block build Note that a single platform class can only support a finite variety of payloads and capabilities Using a common platform for many missions involves varying degrees of inefficiency Slide 16

17 Slide 17 Session #2: Small Satellite Key Technologies for Remote Sensing Common EO Platforms: An Example Global Hawk is a Common Platform, utilizing an Open Architecture to support a variety of Payloads Courtesy of Nothrup Grumman

18 Integration, Assembly & Test Design Session #2: Small Satellite Key Technologies for Remote Sensing Standardization Concepts and Terms Standard Interfaces Pre-specified boundary and limits for interaction across boundary Standard Parts Units with identical form and function that form a distinct portion of different systems Standard Architectures (Common Bus, Standardized Bus, Scalable Bus, Modular/Reconfigurable Bus) Defined ways of configuring and connecting parts of system Standard Integration and Assembly (e.g. Iridium) Set process for building up systems Standard Verification Process (e.g. MIL-STD-1540) Repeatable methods for determining requirements satisfaction for different systems Slide 18

19 Standard SC Bus Approaches Fixed/Common Bus Designed to envelope all potential payloads Identical bus builds with different payloads from the same user (e.g. EOS) Identical planning and documentation for testing and verification (using worst-case envelope) Can use one set of qual units / EMs / spares for multiple buses Standardized Bus Designed to envelope all potential payloads Uses standard interfaces to different payloads from different users (e.g. STEP) Partial commonality in testing / qual approach (different users) Scalable Bus Maintains standard interfaces within bus, but parts are resized to fit mission Modular Bus Modularity removes need for a single bus designed for all potential payloads Uses standard architectures to configure parts of the system Each module has a series of options with different levels of capability Slide 19

20 Standards Efforts PnPSat: Complete system modularity Applique Sensor Interface Module for COTS-PnP-retrofit F6: Future Fast, Flexible, Fractionated, Free-Flying Spacecraft united by Information exchange Complete abstraction of traditional monolithic design Courtesy AFRL SIV: Standard Bus + Flexible Payload Interface Bus capable of operating in virtually any LEO orbit Prescribed payload mass, power, env. limits ensure compatibility and manifest. Courtesy DARPA ORS: Capability on Demand TacSat series of experiments Established interface standards for all system segments Courtesy NRL & JHU/APL Courtesy Ball & AeroAstro Courtesy ATK Slide 20

21 Standardization Summary Standardization can be applied to spacecraft design to varying degrees through parts, interfaces, and architectures Experience with spacecraft standardization has met with varied success over the last several decades Typically most successful when the range of applicability is relatively narrow (bus is used for missions it was originally designed for) and there is high volume (demand for key mission) There are some common themes that have been observed Flexibility, if desired, must be planned for from the onset of the program (design spacecraft to performance envelope) Missions and payloads tailored to capabilities of bus (limit in performance traded for standardization benefits to cost, schedule, reliability) Development of spacecraft design standards require upfront investment in order to achieve benefits in long term (return on investment not realized until several spacecraft have been built) Slide 21

22 NASA Small Satellite Study Small Explorer Program Office interested in current and new small satellite capabilities: Spacecraft systems Component technologies Draw from industry, gov., international Ready or near-term availability: Technology Readiness Level (TRL) 4 Results will be utilized to inform government and industry community: Offerings Potential gaps for future investment Will be openly published ~ April 2008 Your input needed! Slide 22 Component and/or breadboard validation in laboratory environment

23 Summary & Hand-Off Small Satellite Utility Currently: o Obstacles: Access to space o Niche market, missions, and applications o Provide Good Enough capability o Complementary to large systems o R&D focused on key technology enablers o Standard platforms being revisited potential cost savings Future: o New launch and manifest options poised o Technology advances reducing capability as ƒ(sc size) gap o Standard and modular interfaces access, flexibility, schedule o Community embracing approach Slide 23