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RAFT Radar Fence Transponder Mission Completion Review 6 May 08. Bob Bruninga, CDR USN (ret) MIDN 1/C David Koeppel MIDN 1/C Brent Kolb MIDN 1/C Jeff Robeson MIDN 1/C Kyle Vandegriff. Key Milestones: Schedule. RAFT Kickoff Apr 04 RAFT USNA SRR Sep 04 RAFT PDR 19 Nov 04
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RAFTRadar Fence TransponderMission Completion Review 6 May 08 Bob Bruninga, CDR USN (ret) MIDN 1/C David Koeppel MIDN 1/C Brent Kolb MIDN 1/C Jeff Robeson MIDN 1/C Kyle Vandegriff
Key Milestones: Schedule • RAFT Kickoff Apr 04 • RAFT USNA SRR Sep 04 • RAFT PDR19 Nov 04 • RAFT Phase 0/1 Safety 16 Dec 04 • RAFT Phase 2 Safety 10 Feb 05 • RAFT CDR 23 Feb 05 • RAFT Flight Unit Testing 26 Jan 05 • RAFT Phase 3 Safety 22 Feb 06 • RAFT Delivery/Install July 06 • RAFT Flight (STS-116) Dec 06 • De-Orbit 30 May 07
Mission: So Many CUBEsats 30 to 50 in Construction How to Track ??? AIAA/USUSmall Sat Conference 30% of papers were for PICO, NANO and CUBEsats All smaller than 10 cm
Mission Statement • To provide the Navy Space Surveillance (NSSS) radar fence with a means to determine the bounds of a constellation of PicoSats otherwise undetectable by the radar fence • To enable NSSS to independently calibrate their transmit and receive beams using signals from RAFT. • This must be accomplished with two PicoSats, one that will actively transmit and receive, and one with a passively augmented radar cross-section. • Additionally, RAFT will provide experimental communications transponders for the Navy Military Affiliate Radio System, the United States Naval Academy’s Yard Patrol crafts, and the Amateur Satellite Service. • RAFT1 Education for 16 Astronautics Majors Senior projects Robeson, Paquette (06) - Orloff, Kinzbrunner, and Rose(05) - Baker, Tuttle, Colvin (04) Abbott, Atwater, Brandt, Hansen, McLean(03). And 3 in (02)
NSS Radar Fan beam (E/W) • Horizon to Horizon down only -6 dB
NSS Fan Beam N/S • Only 0.8 degrees North/South
XP-217 Radar Fence Transpopnder • Design a very small receiver for the NSSS Radar suitable for a cubesat • Include an Oscillator for NSSS to hear us. Northeastern University GSI Lumonics
Fail-Safe Reset Timer • Cold boots CPU if no TLM every minute
Simplified Power System 60 mA Charge in Parallel 100 mA 100 mA Charge in Parallel and TX in series Transmit in Series Duty cycle 4%
RAFT1 Network Architecture Global Volunteer Ground Station Network Internet Linked for live Telemetry
RAFT1 Mission Architecture APRS Global Packet Radio Network Internet Linked for live Communications
SCIENCE USNA-0203 Space User Baseline See www.ariss.net PCSAT validates our links APRS Satellite User Plot 18 Apr 06 Vandegriff
Military Affiliate Radio System • The Mission of the MARS system is to: • Provide auxiliary communications for military, federal and local disaster management officials • Assist in effecting communications under emergency conditions. • Handle morale and quasi-official communications traffic for members of the Armed Forces and authorized U.S. Government civilian personnel • Provide routine operations in support of MARSGRAMS and … contacts between service personnel and their families back home home.
MARScom Mission Architecture Military Affiliate Radio System
Yard Patrol Craft Application Unique UHFAM Uplink and HF SSB downlink
RAFT1 and MARScom 5” Cubes 3 Antennas Each Identical Mechanical
RAFT1 and MARScom 5” Cubes 3 Antennas Each Identical Mechanical
RAFTDeployment Velocity of pair: 1.8 m/s Velocity of RAFT: 2.6 m/s Velocity of MARScom: 1.2 m/s Was 1.5, 1.3 & 1.8
Raft1 Electronics Systems TNC Interface Brd
Raft1 Electronics Systems Transmitter Receiver and XP-217
RAFT1 Internal DiagramTopView Ant pocket & Sep SW
MARS Panels and Boards RCVR Batteries and TX-Interface board TNC
GSE Side Panel COTS Silicon Cells on PCB panel Covered with Clear Teflon Coating 1.5 Watt panel Mechanically rugged for rain/hail/birds PCsat Flight Heritage Windup port GSE port
Top Panel VHF Antenna holes HF whip hole Pockets for other satellite antennas and Sep Switch
RAFT1 Lead Ballast Encapsulated in Kapton tape
RAFT Lifetime Estimate 2.5 Mo 6.5 Months
Long-Wire Antenna ~2.5”
ANDE/RAFT - USNA Pre-Launch Intgration and Prep
RAFTmicrogravity Separation Test March 30th – April 8th (“Test of Opportunity”) Robeson
Sequence • We suspect a stuck antenna. • Maybe one of the four antennas, after being compressed in the pre-launch configuration for maybe 6 months prior to launch against the bottom of the antenna sleeve, may have embedded itself into the Scotch 2216 Epoxy. • At the instant of final separation, that momentary impulse for the “stuck antenna tip to release” imparted torques on the spacecraft. • Marscom ended up at almost 80 RPM and RAFT at about 40 RPM … Play Video …