Subsystem Requirements LionSat Subsystem Detailed Requirements Listing Document Number: 00-001 Revision Number: - 3.0 Authors: Joseph Musser Approved By: _ Document Author Date Systems Integration _ Date Program Manager _ Date Signatures on file (Y/N): _ Department of Electrical Engineering 129 Electrical Engineering East University Park, PA 16802 Phone: (814) 863-2788 Fax: (814) 865-0765 Design Document 00-001 Department of Aerospace Engineering 233 Hammond Building University Park, PA 16802 Phone: (814) 865-2569 Fax: (814) 865-7092 June 30, 2004 1/31 Subsystem Requirements Revisions Revision Number 1.0 Revision Description Date Signature of Approval First Release Design Document 00-001 June 30, 2004 2/31 Subsystem Requirements Table of Contents ………………………………………………………………………… Design Document 00-001 June 30, 2004 3/31 Subsystem Requirements LionSat (Local Ionospheric Measurements Satellite) The Pennsylvania State University University Nanosat III Mission Requirements #1 The plasma environment mapping throughout the entire perturbed region (i.e., ram and wake) must be resolved to 30±5 degrees about the satellite spin axis #2 The electron density and temperature of both the unperturbed and perturbed regions around the nanosatellite must be collected and returned to the ground for a minimum of three separate geophysically meaningful campaigns #3 The miniature RF ion thruster must demonstrate a minimum of one hour of continuous operation #4 The miniature RF ion thruster must demonstrate a measurable change in the satellite rotation rate System Requirements #1 frequency of LionSat should be above 100 Hz ? Actual frequency? #2 LionSat’s physical envelope should satisfy the requirements described in the AFRL Internal Cargo Unit User’s Guide UN-0001 rev July 2003 #3 Safety requirements from Internal Cargo Unit User’s Guide UN-0001 rev July 2003 #4 LionSat will be mounted to the Internal Cargo Unit via a Planetary Systems Corporation Lightband system The description of the mechanical and electrical interfaces are given in the following documents: AFRL Internal Cargo Unit User’s Guide UN-0001 rev July 2003 and PSC document 2.000.510 #5 LionSat should be able to withstand the critical thermal environments encountered during launch and while in space ? Max/Min temp? Design Document 00-001 June 30, 2004 4/31 Subsystem Requirements #6 LionSat should be designed to withstand the vibroacoustic environment of the shuttle without failure as described in the UN-0001, §6.3.3.5 #7 LionSat should be able to operate in the vacuum conditions encountered in space ? Vacuum capable? #8 LionSat should be able to withstand the depressurization and repressurization rates mentioned in the UN-0001, § 6.3.3.6 and a venting analysis should demonstrate a factor of safety of 2.0 #9 LionSat should meet the technical and safety requirements described in NSTS 1700.7B (i.e., failure tolerances and catastrophic hazards) #10 The system should meet the margins of safety described in UN-0001 To meet this requirement, a stress analysis as described in the Stress Analysis Guideline UN-SPEC-12311 must be performed #11 LionSat will use inhibits to control hazardous functions as described in the NSTS 1700.7B Thermal Requirements #1 Provide adequate thermal protection for the spacecraft during all mission phases along with a complete thermal analysis AFRL User’s Guide UN-0001 #2 Complete a preliminary analysis of the thermal subsystem, determining the worst case hot/ cold temperatures for the spacecraft during the mission #3 Further the thermal design with a one-node analysis of the spacecraft (STK) #4 According to document UN-0001, thermal models must be supplied to AFRL, at a minimum including a simplified model which includes nodes for each of the temperature-critical components (SINDA) #5Provide temperature limits as defined by UN-0001 for each node in the reduced thermal math model and for each subsystem #6Determine all heat sources and their respective profiles during the various mission phases UN-0001 #6The heat transfer must be quantified for the satellite to the external environment (ICU or space) UN-0001 Design Document 00-001 June 30, 2004 5/31 Subsystem Requirements #7 Determine temperature-critical components UN-0001 #8Determine all payload external surface properties including size, material/ process, absorptivity, and emissivity values UN-000 #9Component Operating Temperatures must stay within the limits of the worst case hot and cold temperatures found in the one node analysis # 10 Component Operating Temperatures must conform to temperature limits set by thermal computer analyses (SINDA) • Thermal classification: Passive – Control Types: Paints, Coatings – Thermal verification – Temperature Sensors – Thermal Analysis Batteries to 40 - 30 to 50 Component Operating Storage (NiCad) Temp Temp (°C) (°C) Power control - 40 to 85 -40 to 85 Unit RF Probes -40 to 85 -65 to 150 Magnetometer to 70 TBD GPS - 30 to 75 -55 to Magnetic TBD TBD 90 Torquer Onboard to 70 -40 to Sun Sensor - 40 to 85 -40 to 85 Computer 85 RF Ion TBD TBD Transmitter - 20 to 70 -55 to Thruster 100 Boom Motor TBD TBD Command - 40 to 85 -40 to GPS Antenna - 40 to 105 -40 to 105 Receiver 150 • • First-order, one-node, spherical-payload analysis Temp Range: Tmax = 38 oC steady state full sun Tavg = 10.5 oC – Multi Node Analysis (SINDA) Temp Range: TBD Spacecraft Temperature Ranges Design Document 00-001 June 30, 2004 6/31 Subsystem Requirements Mechanical Sub System: Structures Technology Lead(s): Peter Cipollo Structure and Mechanism Requirements #1Mass must be no more than 30 kg and center of gravity (CG) location must lie no further than 0.25” from ICU centerline in accordance with University NanoSat Document UN-0001, Rev-Issue Date 7/03, §6.1.2, §6.1.3, and §8.2 Get this data from pete #2 Structure able to withstand maximum unidirectional test loadings of 23.8 G’s in accordance with University NanoSat Document UN-SPEC-12311, Rev-, §2.1 data FROM PETE #3 Following integration of ring and satellite, AFRL will verify that the mass/CG properties of the LionSat System fall within the constraints specified in the University NanoSat Document UN-0001, Rev-Issue Date 7/03 #4 Structure designed to allow for ground handling and transportation as approached by Spacecraft Structures and Mechanisms (Sarafin, 1995, pp 52-54) and University NanoSat Document UN-0001, Rev-Issue Date 7/03, §6.3.3.4 #5 Structure must be free of pressurized components that not meet the requirements defined in NASA-STD-5003 and University NanoSat Document UN-0001, Rev-Issue Date 7/03, §6.3.3.8 #6 Design Factors of Safety (FOS) for the structure must be met and/or exceeded, as well as, Margins of Safety (MS) must be zero or greater for both yield and ultimate stress conditions as stated by University NanoSat Document UN-0001, Rev-Issue Date 7/03, §6.1.2, §6.3.3.2, and §8.1.1 #7 AFRL will verify that the integrated ICU/LionSat System can exceed requirements for the following testing: Sine Sweep, Sine Burst, and Random Vibration (University NanoSat Document UN-0001, Rev-Issue Date 7/03, §8.1.3 Design Document 00-001 June 30, 2004 7/31 Subsystem Requirements #8 Payload stiffness must exceed 50 Hz and a fixed base natural frequency greater than 100 Hz according to University NanoSat Document UN-0001 Rev-, §6.3.1 #9 Hardware should be qualified for the Space Shuttle vibroacoustic environment with regards to University NanoSat Document UN-0001 Rev-7/03, §8.1 #10 Fracture control assessment should be done to remove all plausibility of catastrophic hazards to Shuttle Orbiter or Crew following NASA Document NASA-STD-5003, Rev- and University NanoSat Document UN-0001 Rev-, §8.3 #11 Pressure Profile Analysis on all of NanoSat-3 hardware must be completed for pressurization and depressurization environments using values from University NanoSat Document UN-0001, Rev-7/03, §6.3.3.6 #12LionSat’s physical envelope should satisfy the requirements described in the AFRL Internal Cargo Unit User’s Guide UN-0001 rev July 2003 Subsystem Structure Power Propulsion Hybrid Probe Communications GNC C&DH Margin Total Estimated mass (kg) 10.18 8.6 1.1 0.37 1.07 0.5 6.18 30 Subsystem Structure Power Propulsion Hybrid Probe Communications GNC C&DH Margin Total Actual mass (kg) ? ? ? ? ? ? ? ? ? Design Document 00-001 June 30, 2004 8/31 Subsystem Requirements >Spacecraft structure octagonal in shape with diameter of 18.50 in (47 cm) and height of 18.31 in (46.5 cm) Top End Cap       mounting point/fasteners for xenon tank, valves, and pipe work at least holes for solar cell wiring magnetometer mount/fastener—hole for wiring cable braces sun sensor mount/fastener—hole for wiring 24 (3 per side) #6 tapped holes on flange for attaching side panels Bottom End Cap         at least six holes for solar cell wiring light band connection—24 ¼ “ holes for mounting satellite sun sensor mount/fastener—hole for wiring light band insulator cable braces mounting points/fasteners for mounting boxes holes for light band power inhibitor switch connection ports 24 (3 per side) #6 tapped holes on flange for attaching side panels Side Panels          mounting points/fasteners for whip antennas 2-holes for boom deployment (1 hole in two opposite side panels) sun sensor mount/fastener—hole for wiring at least ten holes per side panel for solar cell wiring cable braces mounting points/ holes/ fasteners for thruster nozzles (in two opposing side panels) mounting points/fasteners for thruster piping/ wiring torque rod mounting points/fasteners 14 holes for connection to neighboring side panels and end caps o #6 flat head holes for top and bottom of panel o #4 flat head holes per side Boom System Construct booms and deployment system  Boom design/construction Design Document 00-001 June 30, 2004 9/31 Subsystem Requirements  Boom deployment system o Inhibits #1 Booms must be deployed after safely away from ICU/Launch Vehicle (Nanosat Program Requirement) #2 Probe delivery equipment( boom design) Mass, volume and power requirements Thrusters  Fuel tank/pipe system o Valves Mounting Boxes Flight Computer SA1110 &Memory -need connection points for o Power/GND o SSP Data Bus o I/O Lines (chip selects) o RS-232 Port o Light Band Interface (power/GSE) o House Keeping Sensors o Downlink Data o Uplink Data Analog/Digital Sensor Board -need connection points for o SSP Bus, chip select o Analog inputs o Digital inputs o Power GPS Receiver -need connection points for o Power/GND o RS-232 o Power Combiner Torquer Controller -need connection points for o Power/GND Design Document 00-001 June 30, 2004 10/31 Subsystem Requirements #3 Side panels Each panel will hold 60–72 cells “Belly band” ensures space for motorized booms and TM slot antennas Battery 10 Sanyo N-4000DLR type 1.2V cells stacked to make 12V **Each cell must have leads coming off of it so that each cell voltage can be individually tested after they are packaged *Inhibit on battery return through light band **Thermistors on each cell separate from computer monitor Overall voltage and temperature sensor Construction of battery box - Hazleton? Charger: Low power consumption for electronics Charge battery from dead Maintain battery charge with excess current from solar cells Shut down when batteries are sourced for extra power a Startup in sunlight i Normal charge ii Trickle charge iii Recover from depth of discharge b Shutdown when on dark side to prevent power drain by charger electronics Multiplex panels to take advantage of partial illumination? a Step-up converters? Simulation of depth of battery discharge for each sub system running alone and in combinations with other systems i Time to charge batteries while computer in low power mode after first entering orbit ii Minimum satellite draw in a low power mode Recovery time from depth of discharge iii Worst case satellite power draw Recovery time from depth of discharge iv Depth of Discharge for each operational mode (experiment combinations) DC/DC Converter (on each subsystem) Watch dog to power on computer when battery supply is sufficient to run computer on dark side (may put this on computer) Switches for each subsystem to power on/off (none for computer) a Read Sync Serial Port + chip select for subsystem on/off info Outputs a 1000V Ion-Thruster b +5V Magnetometer/GPS/Computer/HPP Design Document 00-001 June 30, 2004 17/31 Subsystem Requirements c -5V Magnetometer/HPP d 3.3V Computer/GPS/HPP e +12V HPP/Boom Deploy/Thruster/Torque Rod/Comm./Amp f -12V HPP/Amp g Common All systems #1 Converters: Interpoint MHE1205S; Datel UNR-3.3/3-D12; PICO MRF5S, MRF15D, 12AV1000 #2 Interfaces Connector types: NLS0H14-35S for EGSE monitors, NLS0H1035S for SC power Fusing/Circuit protection: FM08A125V7A (50% derated) Wiring-rating, material: MIL-W-22759/20, #20 AWG, PTFE insulated (200 C) #3Battery recharge currents Grounding/Bonding Provide a continuous, electrically conductive path between each major structural component and ICU AFRL University Nanosat Internal Cargo Unit (ICU) User’s Guide – §6.5.3, rev July 2003 #4Requirement: Iarray > recharge + operation (68% normal ops.) Performance: 20% margin #5Depth of discharge (DoD) 4-week minimum mission 450 cycles Requirement: < 30% Performance: 12% (8.2% for normal ops.) *Inhibits Light band switch on solar cell return (disconnect till deployed) Light band switch on battery return 3.Safety: Thermistor temp monitor, EGSE volt monitor, zener volt clamp if PCU fail Number and type of grounds: One power-to-SC frame ground connection implemented by relay contact energized by recharged battery after deployment #1 Battery cell temperature monitor Prevent temperature related failures AFRL University Nanosat Internal Cargo Unit (ICU) User’s Guide – §6.6, rev July 2003 #2 Battery cell voltage monitor Prevent overcharge AFRL University Nanosat Internal Cargo Unit (ICU) User’s Guide, rev July 2003 #3 Safety Batteries initially discharged until separation from the ICU Separate interlock disconnect of solar array and battery pack until separation from cape no power until solar array illumination adds third safety defeat AFRL University Nanosat Internal Cargo Unit (ICU) User’s Guide – §6.5.1, rev July 2003 Design Document 00-001 June 30, 2004 18/31 Subsystem Requirements **GSE Test leads off each battery cell in battery package for sensing cell voltage Feed leads to connector on battery box Test leads from Light Band inhibits to power system must be brought out to Light Band header Battery Testing Flight units provided by Nanosat-3 System level thermal & vibration testing followed by battery servicing Temperature and voltage monitoring during thermal testing Sub System: Light Band Technology Lead(s): Yashar Fakhari, Brendan Surrusco Design Document 00-001 June 30, 2004 19/31 Subsystem Requirements *2 inhibit switches a Solar cell return disconnect b Battery return disconnect **15 pin connector (2) a Battery voltage outputs b Boom deployment sensors (4 = stowed, deployed) c Xe gas tank pressure d Ethernet communications with flight computer Sub System: GPS Technology Lead(s): Brendan Surrusco GPS receiver running on 3.3 or 5V RS-232 communications to computer Antenna array of patches around belly band a patches each 45 degrees from a plasma probe Software application for logging position, velocity, time, visible satellites and satellite SNRs Software should also maintain system clock using GPS time Investigate JNS100HDA from JAVAD.com a Same specs as JNS100 but for aerospace Sub System: Communications Technology Lead(s): Kevin Lin, Denis Ng Chong, Brendan Surrusco/Mike Caldwell Hardware Power amplifier for transmitter with disconnect and reroute to prevent complete loss of signal if amp dies (2.365GHz carrier + BW for at least 200Ksymbols/sec) TX and RX antenna system (test model on satellite mock up first) a Quadrifilar? b Coils? c Whips centered on side panels? i vertical and aligned with end cap ii horizontal and aligned with end cap iii Mix horizontal and vertical d Associated antenna hardware (power splitters, band pass filter for RX section) Define/build link between computer and transmitter Design Document 00-001 June 30, 2004 20/31 Subsystem Requirements Build receiver board for Honeywell transceiver chip a Build a down converter to take uplink RF down to transceiver input frequency b Define digital link to computer Communication Requirements Science Data  Roll rate of ~10 rpm 14,400 rolls/day  12 samples per roll  sensor heads 691,200 samples/day Functional Swept Objective Plas FP 5% 100 Swept Bias LP 10% 20 2.5 Tracking Plas FP 40% 40 Fast Temp P 10% 10 Fixed Bias LP 35% 30 97.5 Portion of day 15% 1.5 15 100 MB/day 11.0 10.6 11.0 10.2 Data Per Sensor Subunit Science: Functional Objective dependent MB/day 11.0 Magnetometer: (for science and attitude) B/sample • 172,800 samples/day 1.04 GPS: (for orbit determination and time) 20 B/sample • 0.1 samples/second 0.17 Housekeeping: temp., 40 voltage, 10 current, tank pressure, and horizon sensors B/sample/ch • 61 ch’s • 0.1 samples/second Total: 13.3 MB/day to download 1.05 Ground Station Ground Station #1Operations Design Document 00-001 June 30, 2004 21/31 Subsystem Requirements Operated by undergraduate students Located on Penn State campus Latitude = 40.8, Longitude = -77.9 Receiving and commanding Tracking verification (onboard GPS, NORAD for backup Design mounting base for ground station dish to go on top of Deike building a Finished 4/04 Build platform and raise dish via OPP Repair dish drive amp Software Radio with IP capacity Transmitter using Honeywell transceiver chip Uplink power amp Setup ground station equipment (receiver/transmitter and dish hardware) in Deike building Add a router to ground station in Deike to move data to Mission Operation Center (MOC) over PSU network #1Hardware 3.6-m S-band dish Downlink: Microdyne frontend Uplink: S-band Tuscon Amateur Packet Radio Trakbox microcontroller Discussions with Embry Riddle for shared tracking for/by Eagle Eye Software Implement IP protocol on satellite as defined in NASA provided IP hand book Write ground station dish control software controlled and monitored via web page that can be accessed via MOC (dish control info passed via router at ground station) Software radio in a PC at ground station Secure FTP and Web browser for data transfer to and from LionSat a Auto receive via UDP when LionSat broadcasts #1 Software STK Toolkit from Analytical Graphics, Inc Penn State site license includes HPOP, High Precision Orbital Propagator Trakbox firmware MATLAB-based software radio development (digitized IF) COMM: Link budget Design Document 00-001 June 30, 2004 22/31 Subsystem Requirements Communications Requirements #1Requirements Downlink frequency = 2.365 GHz Downlink data rate = 200 ksymbol /sec Uplink data rate = 9.6 ksymbol/sec #2 Radio Xmittr: L-3 Comm T-155 0.5 W output, FM modified for PM, W Power Amp, NE6510179A Receiver: Honeywell HRF-ROC09325 Front end, WJ mixer, RF amp, etc 85 grams, 1.3 in3 24 grams, 0.75 in3 45 grams, 3.3 in3 50 grams, TBD #3 Uplink/Downlink antennas Slot antennas under development ~160 grams, dimensions TBD Located on bellyband, four sides for uplink, four sides for downlink Omnidirectional pattern with nulls #4 GPS antennas: Microstrip patches (TOKO DAX1575MS63T) on eight sides #5 Link requirements ~400 km altitude, 51 inclination (Shuttle Orbit) ~Six sequential overpasses/day Reacquisition needed for each pass Maximum path length 1470 – 1840 km maximum tdelay ~ 4.9 – 6.1 ms Data generated on satellite, asymmetric link LionSat initializes handshake based on GPS and ephemeris data If no response, LionSat broadcasts in the blind Design Document 00-001 June 30, 2004 23/31 Subsystem Requirements 200 ksymbols/sec downlink; 9.6 ksymbol/sec uplink #6 Protocol options Lionsat will use IP communications for return of science data After mission criteria met, can be used as testbed for testing/verifying relative performance of various protocols #7 Status of frequency allocation: current satellite transmitter unit (T-155) is designed for 2.365 GHz (military band), waiting for Nanosat-3 guidance Ground Support and Equipment #1 Electrical Control suitcase Umbi through CAPE adapter Umbi for direct connection to LionSat #2Laptop with Ethernet connection #3 Safety inhibit verification #4 Power on/off overrides #5 Battery charging Volt / current / temperature monitors #1 Mechanical Design Document 00-001 June 30, 2004 24/31 Subsystem Requirements holes drilled (17/64” dia.) on top end cap for hoist rings (used for lifting and moving after initial transportation) #2 Transportation box Prelim Design includes: Dummy LBR to secure satellite: May be lowered and connected directly to box >Airtight to protect hardware >Will look at vendors for box that can be combined rigidly with simulated LBR for transportation Sub System: Sensor Board Technology Lead(s): Ludovic Polak, Yashar Fakhari Communicate with computer via Synchronous Serial Port and Chip Select a Serial port transmitter disconnect to allow other systems to use the line Multiplex in data from sensors and send them via SSP to computer No processing of signals on sensor board? 30+ sensors a 10 sun sensors – voltage off one solar cell string per panel, lump with regular voltage readings in part e b axis magnetometer – channels, one per axis c Battery overall temperature d Battery overall voltage e 10 solar cell temperature sensors (one behind each panel and end cap) f Solar cell string voltage sensor (one per string of 20 cells) g CPU temperature h GPS temperature i Power amp temperature j Transmitter temperature k Receiver temperature l Power unit temperature m **Xe gas tank pressure n separate boom stowed sensors o separate boom deployed sensors p HPP sensors? q Thruster sensors – RF power generator temp r Others? C&DH Requirements Mission Requirement Design Document 00-001 Method June 30, 2004 Status 25/31 Subsystem Requirements Data collection, formatting, communication Requirement: MIPS and memory Performance: TBD Design and test Eval board Attitude determination and control Requirement: 5° Design Simulation Design and test Planning Design Performance: timed- and test Planning Power management Requirement: Time-line control of control of operational modes (PCU) Boom deployment Requirement: no stored energy delayed Performance: 1–5° Performance: Power Control Unit motor C&DH Requirements #1 Data/Communications Run OS and subprograms (RT Linux) Data processing Data storage Data forwarding Transmitter/power amp operation IP (Internet Protocol) in space #2 Guidance, Navigation, and Control Attitude management Magnetometer Sun sensor Magnetic torque rods GPS #3 Power Systems Monitor solar panel temperature and performance Monitor battery temperature and performance On/off control of subsystems C&DH Processor #1 Physical Characteristics Main components CPU - Intel SA1110 @ 206MHz (baseline) SA1110 Memory Up to 768 MBytes static memory such as SRAM, FLASH, SMROM Design Document 00-001 June 30, 2004 26/31 Subsystem Requirements Up to 512 MBytes dynamic memory SA1110 subsystems interfaces 28 GPIO lines Multiple serial systems (SPI, UART, USB…) Ground interface through TCP/ #2 Performance Characteristics Power consumption Ix, Iy Analysis Underway Simulation Simulation Completed Test Design Underway ADCS Performance Requirements #1 altitude determination Attitude estimation : ±1~5° Attitude determination with a 3-d magnetometer only (angular velocities and integration to find Euler angles or Quaternion) Attitude update with a Sun sensor Algorithm to process two vector observation : TRIAD or QUEST #2 aitude control Maintain orientation within ±5° Successful correction of error caused by regression of RAAN Design Document 00-001 June 30, 2004 30/31 Subsystem Requirements Regression of RAAN ±5°/day (at 400km, i = 52°) Nutation damping with passive damper #3 Type of ADCS Spin stabilization using geomagnetic field and magnetometer only attitude determination Passive nutation damping #4Magnetic torque rods Mass depends on size of rods For 10–15 A•m2 magnetic moment rods ~0.5 kg Mechanisms Controller decides polarity of rod to change Tmg Two magnetic torque rods will be used to maintain desired attitude #5 Power consumption: W per axis Torque 510–5 N•m at 400-km altitude #6 Operational modes Orientation control Spin-rate control Stand-by (idle) #7 Start-up/activation At separation from launch vehicle approx spin rate of 5–10 rpm will be provided Then, orientation change to desired spin axis orientation Finally, spin rate control, if desired In normal operation, most correction will be orientation control Design Document 00-001 June 30, 2004 31/31 .. .Subsystem Requirements Revisions Revision Number 1.0 Revision Description Date Signature of Approval First Release Design Document 00-001 June 30, 2004 2/31 Subsystem Requirements. .. 00-001 June 30, 2004 3/31 Subsystem Requirements LionSat (Local Ionospheric Measurements Satellite) The Pennsylvania State University University Nanosat III Mission Requirements #1 The plasma... satellite rotation rate System Requirements #1 frequency of LionSat should be above 100 Hz ? Actual frequency? #2 LionSat? ??s physical envelope should satisfy the requirements described in the AFRL