Enabling Space Sensor Networks with PCBSat

Transcription

1 Enabling Space Sensor Networks with David J. Barnhart, Tanya Vladimirova, Martin Sweeting Surrey Space Centre Richard Balthazor, Lon Enloe, L. Habash Krause, Timothy Lawrence, Matthew McHarg United States Air Force Academy Jim Lyke Air Force Research Laboratory/Space Vehicles Jim White Colorado Satellite Services Adam Baker Surrey Satellite Technology Ltd. 21st Annual AIAA/USU Conference on Small Satellites Tuesday, 14 August 2007, 11:15

2 Overview Introduction New Distributed Space Mission Opportunities Very Small Satellite Solutions Current Results Conclusions 2/18

3 Introduction An unrealized class of distributed space missions requires simultaneous observations (in-situ or remote sensing) to create multi-dimensional models of phenomena Some examples: Remote sensing (treaty sentinel, disaster, military, ) Space weather (solar wind, magnetotail, radiation, ) Upper atmosphere (ionosphere, Aurora, drag, pollution, ) Communications research (AMSAT constellation) Not a new idea, but a new approach Leverage recent component miniaturization and existing commercial infrastructures to mass-produce low-cost sensor nodes for massively distributed missions 3/18

4 Example Mission: Plasma Bubbles Large disparity between terrestrial and space weather sensor nodes (~1000:1) Ionospheric plasma depletions plasma bubbles occur in LEO at low latitudes after local sunset Known cause of navigation and communication outages Not well understood and difficult to predict Ideal sensor: the miniature electrostatic analyzer (MESA) 4/18 10x10x3 cm in MISSE-6 configuration

5 Plasma Bubble Mission Architecture 5/18 Launch Creatively deploy satellites Orbit Circular 500 km, 30 degrees Leverage small ballistic coefficient (BC) differences to spread out Not formation flying Lifetime < 3 months due to exceeding comm range or re-entry Communication Ad-hoc mesh or repeater network Downlink relay node

6 Solution: Sub-kilogram Satellites PalmSat SNAP-1 PICOSat UK-DMC GIOVE-A Inmarsat g ~1 kg 6.5 kg 67 kg 166 kg 660 kg 5945 kg g kg 1-10 kg kg kg kg >1000 kg $3-20K $20-200K $0.2-2M $2-10M $10-50M $50-100M $0.1-2B Femto Pico Nano Micro Mini Medium Large What is the smallest useful satellite? SpaceChip CubeSats IRIDIUM GPS 10 g ~1 kg 689 kg 1075 kg Well, that depends on the mission! 6/18

7 Why Sub-kilogram Satellites? Unit costs, including launch, can be as low as $3,000 Allows a disposable mentality due to short life and high redundancy Digital Direct Development Difficult design issues at this scale: Power generation (not enough) Availability of meaningful payloads (physical limits) Communication range (too short) Thermal (too cold) Mass producibility at very low cost is the key! 7/18

8 Comparison of Current Technologies Microengineered Aerospace Systems/ Multifunctional Micro Systems Traditional Picosatellites (CubeSat, PalmSat, etc.) Satellite-on-a-Chip SpaceChip Satellite-on-a-Multichip Module MCMSat Satellite-on-a-Printed Circuit Board Technologies compared using plasma bubble mission Costs include parts, assembly, launch, but no NRE 8/18

9 Microengineered Aerospace Systems Microengineered Aerospace Systems The Aerospace Corp. Multifunctional concepts Angstrom Aerospace Corp., Sweden Ball Aerospace, others Essential high-tech advances Will eventually support formation flying, etc. Costs are currently too high to support our mission concept Co-Orbiting Satellite Assistant proposed in 2003, revised 2005 S. Janson, A. Huang, W. Hansen, L. Steffeney, and H. Helvajian, "Development of an Inspector Satellite Using Photostructurable Glass/Ceramic Materials," in Proc. AIAA Space 2005, Long Beach, CA, 2005, Paper AIAA Silicon Spacecraft proposed in 1995 S. W. Janson, Mass-Producible Silicon Spacecraft for 21st Century Missions, in Proc. AIAA Space 1999, Albuquerque, NM, 1999, Paper AIAA F. Bruhn and L. Stenmark, NanoSpace-1: Spacecraft Architecture and Design after Concluding Phase B, in Proc. 5th Round Table on Micro/Nano Technologies for Space, Nordwijk, Multifunctional Micro Systems proposed in /18

10 Traditional Picosatellites Clyde Space EPS Pumpkin DH 1-kg COTS CubeSat Unit Components $51,303 Launch $40,000 Pumpkin Structure Total: $91, W sunlit average power 257 cm 3 max payload volume Microhard Comm SSTL GPS 10/18 USAFA MESA Payload

11 Satellite-on-a-Chip SpaceChip Feasibility RF Comm on a chip (~1 km range) Configuration: SiGe BiCMOS <10g, 20x20x3 mm Data Handling (rad hard) (asynchronous) Thermal Control (heat sink) Solar selfpowered (<1% eff.) Unit SpaceChip $2,400 Launch $300 Total: $2,700 D. J. Barnhart, T. Vladimirova, and M. N. Sweeting, "System-on-a-Chip Design of Self-Powered Wireless Sensor Nodes for Hostile Environments," in Proc. IEEE Aerospace Conference, Bozeman, MT, 2007, Paper /18 Attitude/ Orbit Control (2-sided, no GPS) (no propulsion) Payloads (some options) (CMOS-MEMS) 1 mw Sunlit Average Power 2.5x10-5 cm 3 max payload vol.

12 Satellite-on-a-MCM MCMSat Feasibility Unit Components $18,845 Launch $4,000 Total: $22, W sunlit average power 12.5 cm 3 available payload volume Payload Antenna (1/4) Inter-grid (1/2) Solar cells (1/8) Avionics MCMSat top MCMSat bottom Common power layer Optional payload Inter-grid (1/4) Battery charge regulator Battery (1/2) Mass storage (1/3) Top 12/18 Bottom

13 Flight Model Development Unit Components $4,031 Launch $8,000 Total: $12, W sunlit average power 12.8 cm 3 available payload volume 13/18

14 Flight Model Development Payload PCB Bus PCB Electronics Electronics - Solar Cells - MESA Structure Radio Battery - Solar Cells - Payloads MESA + 640x480 imager 655 kbits/orbit Structure 10x10x2 cm Al block, 250 g mass Electrical Power (EPS) 700 ma 2-sided solar array, 3.3V bus 645 mah Li-ion battery Data Handling (DH) Data storage Communication 1 W 900 MHz ISM radio, km Repeater/mesh network, 9.6/115.2 kbps Attitude and Orbit Control Passive ADCS via magnets & aero GPS for orbit determination Thermal Passive control 14/18

15 Sub-kilogram Satellite Comparison $100,000 $90,000 $80,000 $70,000 $60,000 $50,000 $40,000 $30,000 $20,000 $10,000 $0 $40,000 $35,000 $30,000 $25,000 $20,000 $15, Unit Cost vs. Constellation Size $1,000,000,000 $100,000,000 $10,000,000 $1,000,000 $100,000 $10,000 $1, Total Cost vs. Constellation Size $2,000 $1,800 $1,600 $1,400 $1,200 $1,000 $800 $600 $400 $200 $10,000 $ Cost/Watt vs. Constellation Size 15/18 Cost/cm 3 for Payload vs. Constellation Size

16 Demonstration Mission STK HPOP shows 10- day mission due to drift (worst-case) 500 km, 30 deg inclination P-POD Deployer 10 s w/mesa sensor 1 CubeSat configured as store-and-forward relay to ground station km communication range goal allows 10-day mission due to drift Longer mission with matched ballistic coefficients (BC) Less than $500K total cost 16/18

17 Conclusions Massively distributed space missions under investigation Recent COTS component miniaturization and existing fabrication infrastructures present an opportunity for low-cost and mass-producible disposable satellites Planned future work flight model qualified by December 2008 Thermal environment, communication range, GPS, and debris mitigation are main concerns Continue development of sub-kilogram concepts SpaceChip, MCMSat, cost modeling Pursue flight opportunities 17/18

18 Questions & Contact Information See and EyasSat at booth #71 18/18