RAFT Radar Fence Transponder Phase III Safety Review Feb 06 Bob Bruninga, CDR USN (ret) MIDN 1/C Jim Paquette MIDN 1/C Jeff Robeson
RAFT Ph-III Safety Review 2Feb 2006 RAFT Kickoff Apr 04 RAFT Kickoff Apr 04 RAFT USNA SRR Sep 04 RAFT USNA SRR Sep 04 RAFT PDR19 Nov 04 RAFT PDR19 Nov 04 RAFT Phase 0/1 Safety16 Dec 04 RAFT Phase 0/1 Safety16 Dec 04 RAFT Phase 2 Safety10 Feb 05 RAFT CDR23 Feb 05 RAFT Flight Unit Testing26 Jan 05 RAFT Phase 3 Safety22 Feb 06 RAFT Delivery/Install Apr 06 RAFT Flight (STS-116) Oct 06 Key Milestones: Schedule
RAFT Ph-III Safety Review 3Feb 2006 Mission: So Many CUBEsats 30 to 50 in Construction AIAA/USU Small Sat Conference 30% of papers were for PICO, NANO and CUBEsats All smaller than 10 cm How to Track them???
RAFT Ph-III Safety Review 4Feb 2006 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.
RAFT Ph-III Safety Review 5Feb 2006 NSSS Radar Fence
RAFT Ph-III Safety Review 6Feb 2006 RAFT1 Mission Architecture
RAFT Ph-III Safety Review 7Feb 2006 MARScom Mission Architecture
RAFT Ph-III Safety Review 8Feb 2006 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.
RAFT Ph-III Safety Review 9Feb 2006 Yard Patrol Craft Application Unique UHF AM Uplink and HF SSB downlink
RAFT Ph-III Safety Review 10Feb 2006 RAFT1 and MARScom 5” Cubes 3 Antennas Each Identical Mechanical
RAFT Ph-III Safety Review 11Feb 2006 RAFT1 and MARScom 5” Cubes 3 Antennas Each Identical Mechanical
RAFT Ph-III Safety Review 12Feb 2006
RAFT Ph-III Safety Review 13Feb 2006 Raft1 Block Diagram
RAFT Ph-III Safety Review 14Feb 2006 Radar Fence Pass Geometry
RAFT Ph-III Safety Review 15Feb 2006 MARScom Block Diagram
RAFT Ph-III Safety Review 16Feb 2006 RAFT Lifetime Estimate 6.5 Months 2.5 Mo
RAFT Ph-III Safety Review 17Feb 2006 RAFT Deployment 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
RAFT Ph-III Safety Review 18Feb 2006 Flight Model Separation Test
RAFT Ph-III Safety Review 19Feb 2006 Mechanical Design
RAFT Ph-III Safety Review 20Feb 2006 Assembly Plan
RAFT Ph-III Safety Review 21Feb 2006 Solar Panel Design on 5 Sides COTS Silicon Cells on PCB panel Covered with Clear Teflon Coating 1.5 Watt panel Mechanically rugged for rain/hail/birds PCsat Flight Heritage
RAFT Ph-III Safety Review 22Feb 2006 Multi-Function Top Panel VHF Antenna holes HF whip hole Pockets for other satellite antennas and Sep Switch
RAFT Ph-III Safety Review 23Feb 2006 Top Panel
RAFT Ph-III Safety Review 24Feb 2006 RAFT1 Internal Diagram Top View Ant pocket & Sep SW
RAFT Ph-III Safety Review 25Feb 2006 Inside View
RAFT Ph-III Safety Review 26Feb 2006 Side Panel
RAFT Ph-III Safety Review 27Feb 2006 Side Panel Detail Loaded Side.25” thick
RAFT Ph-III Safety Review 28Feb 2006 GSE Side Panel GSE port Windup port
RAFT Ph-III Safety Review 29Feb 2006 Ballast for RAFT1
RAFT Ph-III Safety Review 30Feb 2006 RAFT1 Lead Ballast Encapsulated in Kapton tape
RAFT Ph-III Safety Review 31Feb 2006 For SSPL4410 with MEPSI: PICOSAT mass m = 1.6 kg = 3.5 lbs Preload > { 24 g x 3.5 lbs = 84 lbs } F = 125 lb max preload + 24 g x 3.5 lb 210 lbs 24 g calculated in SVP For SSPL5510 with RAFT: PICOSAT mass m = 7 kg = 15.4 lbs Preload > { 24 g x 15.4 lbs = 370 lbs } F = 500 lb max preload + 24 g x 15.4 lb 870 lbs SSPL4410 LAUNCHER: Preload and Launch Loads credit:
RAFT Ph-III Safety Review 32Feb 2006 Side Panel Buckling Analysis
RAFT Ph-III Safety Review 33Feb 2006 Structure Displacements
RAFT Ph-III Safety Review 34Feb 2006 Depressurization Rate.040 hole Gives 2:1 margin for depressurization
RAFT Ph-III Safety Review 35Feb 2006 Battery Box
RAFT Ph-III Safety Review 36Feb 2006 Battery Box Durette Gold Gortex
RAFT Ph-III Safety Review 37Feb 2006 RAFT Antenna Separation Mechanisms
RAFT Ph-III Safety Review 38Feb 2006 RAFT Antenna Springs
RAFT Ph-III Safety Review 39Feb 2006 RAFT Antenna Springs
RAFT Ph-III Safety Review 40Feb 2006 Antenna Buckling Analysis
RAFT Ph-III Safety Review 41Feb 2006 Long-Wire Antenna ~2.5”
RAFT Ph-III Safety Review 42Feb 2006
RAFT Ph-III Safety Review 43Feb 2006 Electrical Systems And Connections Each panel one pigtail All plug into Interface Board on the PSK panel RAFT1 Panels and Connectors
RAFT Ph-III Safety Review 44Feb 2006 Raft1 Electronics Systems TNCInterface Brd
RAFT Ph-III Safety Review 45Feb 2006 Raft1 Electronics Systems TransmitterReceiver and XP-217
RAFT Ph-III Safety Review 46Feb 2006 MARS Panels and Boards Batteries and TX-Interface board RCVR TNC
RAFT Ph-III Safety Review 47Feb 2006 EPS and Solar Power Budget
RAFT Ph-III Safety Review 48Feb 2006 Solar Power Budget Conclusion: The PCsat panels per side of the satellite and a 39% eclipse time, an average available bus load of 0.96 watts will be available to the spacecraft.
RAFT Ph-III Safety Review 49Feb 2006 RAFT1 Required Power Budget Whole Orbit Average 10% Depth of Discharge Actual Measured in Standby is.56W
RAFT Ph-III Safety Review 50Feb 2006 MARScom Required Power Budget Actual Measured in Standby is.56W
RAFT Ph-III Safety Review 51Feb 2006 Power System
RAFT Ph-III Safety Review 52Feb 2006 Simplified Power System Charge in Parallel Transmit in Series Duty cycle 4% 100 mA 60 mA
RAFT Ph-III Safety Review 53Feb 2006 Operations Safety Features All Transmitter circuits time-out to OFF
RAFT Ph-III Safety Review 54Feb 2006
RAFT Ph-III Safety Review 55Feb 2006 GSE Equipment Same GSE as PCSAT1, PCSAT2 and ANDE
RAFT Ph-III Safety Review 56Feb 2006 Battery Tests No mass change, no leakage Worst case 10% loss of capacity Design Capacity has a 4 to 20 overdesign factor
RAFT Ph-III Safety Review 57Feb 2006 PCsat Solar Panel I-V Curve discharged Full charge Angle
RAFT Ph-III Safety Review 58Feb 2006 Frequency Coordination RAFT1 ITU Coordination obtained. TX: MHz, 2 Watt, 20 KHz B/W FMTX: MHz, 2 Watt, 20 KHz B/W FM RX: – MHz PSK-31 ReceiverRX: – MHz PSK-31 Receiver RX: MHz AX.25 FMRX: MHz AX.25 FM MHz NSSS transponder MHz NSSS transponder MARScom DD 1494 approved MHz VHF cmd/user uplink MHz VHF cmd/user uplink MHz Downlink24-29 MHz Downlink 123 MHz SAR monitor123 MHz SAR monitor Resonant at MHz
RAFT Ph-III Safety Review 59Feb 2006 Radiation Hazard Test Deployed and Active 11 V/m Pre-Separation 0.11 V/m Antennas Compressed, Shorted, Shielded and Sep-SW OFF
RAFT Ph-III Safety Review 60Feb 2006 Radiation Hazard = None Final Flight Unit = -30 dB +/- 3 dB0.35 V/m
RAFT Ph-III Safety Review 61Feb 2006 Questions?
RAFT Ph-III Safety Review 62Feb 2006 Backup Slides
RAFT Ph-III Safety Review 63Feb 2006 Charge in Parallel Transmit in Series Duty cycle 4%
RAFT Ph-III Safety Review 64Feb 2006 MARScom Lifetime Estimate 4.9 Months 2 Mo
RAFT Ph-III Safety Review 65Feb NEA DEVICE ACTUATES 2. LATCH ROD SLIDES FORWARD 3. DOOR SWINGS OPEN AND LATCHES 4. PICOSATs EJECT Door in open, latched, landing position SSPL4410 LAUNCHER: Operation NOTE: Top Cover and Latchtrain Cover not shown in this view No separation until after both picosats clear launcher
RAFT Ph-III Safety Review 66Feb 2006 Mass Budget (kg) Light mass design for future missions Will ballast for RAFT Actual = kg Actual = kg
RAFT Ph-III Safety Review 67Feb 2006 VHF EZNEC Plots
RAFT Ph-III Safety Review 68Feb 2006 RAFT1 Magnetic Attitude Control
RAFT Ph-III Safety Review 69Feb 2006 Post Cold Test Battery Condition (No Leakage)
RAFT Ph-III Safety Review 70Feb °C Battery Tests Triple walled chamber Sealed for condensation Adding Dry Ice 30 Hour -60C
RAFT Ph-III Safety Review 71Feb °C Battery Test: Thermal Conditions
RAFT Ph-III Safety Review 72Feb 2006 Post -60 °C Charge Temp in Vacuum
RAFT Ph-III Safety Review 73Feb 2006 Post Cold Test Discharge Current 852 mA-H
RAFT Ph-III Safety Review 74Feb 2006 PCsat P-V Curve discharged Full charge
RAFT Ph-III Safety Review 75Feb 2006 Dead Battery Charge Efficiency
RAFT Ph-III Safety Review 76Feb 2006 Dead Battery Recovery Test
RAFT Ph-III Safety Review 77Feb 2006 Dead Battery Recovery Test Batteries fully discharged 1 hour beyond shutdown GSE connected to provide current limited 210 mA per satellite for 60 minutes (simulating sun side of orbit) GSE disconnected, satellites continued to run 50 minutes Conclusion: Even if run down to zero, satellites can recover during next 1 hour of sun to make it through next eclipse with positive power budget
RAFT Ph-III Safety Review 78Feb 2006 Shuttle Safety Requirements Fracture Control Plan Captive & Redundant Fastener integrity Captive & Redundant Structural model of RAFTIdeas model, Buckling Venting analysisDone “ Simple mechanismsAntennas Materials / OutgassingCOTS, Replace Electrolytics Conformal coat PC boardsYes Wire sizing and fusing#24, fuse 1 amp Radiation hazardBelow 0.1v/m Battery safetyYes Shock and vibrationYes
RAFT Ph-III Safety Review 79Feb 2006 Battery Safety Requirements Must have circuit interrupters in ground leg Inner surface and terminals coated with insulating materials Physically constrained from movement and allowed to vent Absorbent materials used to fill void spaces Battery storage temperature limits are -30°C to +50°C Prevent short circuits and operate below MFR’s max Thermal analysis under load and no-load Battery must meet vibration and shock resistance stds Must survive single failure without inducing hazards Match cells for voltage, capacity, and charge retention