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Systems Engineering Chad Fish [email protected] 435-797-0469 GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 1 SOFIE CDR October 7-8, 2004 -1 Presentation Overview • • • • • • • • • Key System Requirements System Design System Operation Technical Resources and Error Budgets Post-PDR System Changes Technical Risks Technical Coordination Summary Supplementary Material – Error Budget Models – Level 3 Requirements Compendium GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 2 SOFIE CDR October 7-8, 2004 -2 Key System Requirements GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 3 SOFIE CDR October 7-8, 2004 -3 Science Objectives • SOFIE will support AIM mission in study of PMCs and the environment in which they form. SOFIE will use differential solar occultation to measure: – Five gaseous species (H2O, CO2, O3, CH4, NO) – Temperature – Particle extinction at 10 wavelengths SOFIE Channel Overview • Channel 1 2 3 4 5 6 7 8 Target Absorber O3 particles H2O CO2 particles CH4 CO2 NO Center (m) Strong band Weak band 0.290 0.328 0.862 1.031 2.60 2.45 2.77 2.94 3.06 3.19 3.37 3.51 4.25 4.63 5.32 4.98 Each SOFIE channel uses two detectors to make three measurements: – Strong band absorption – Weak band absorption – Difference signal (weak band – strong band = ΔV) Remove interference and reduce noise! GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 4 SOFIE CDR October 7-8, 2004 -4 System Requirements IDENTIFIER SHORT DESCRIPTION REQUIREMENT (General Operational) SOF 289 Mission Lifetime Function 25 months following a 1 month on-orbit commissioning. SOF 288 Nominal Operability Operate 95% of the time over any 5 consecutive days during the primary science observation season. SOF 279 Autonomous Operations SOFIE shall be capable of autonomous operations for at least 96 hours. SOF 172 Mission Ops SOFIE shall make 2 solar occultation measurements per orbit, one at sunrise and one at sunset. SOF 175 Time Stamp The SOFIE science data time stamp shall be accurate to within 2.5 msec relative to successive data samples during occultation measurements. SOF 179 Spatial Resolution The SOFIE science data products shall have 3.0 km or less spatial resolution in elevation. SOF 308 Sampling Rate The SOFIE science data channel sample rates shall be ≥ 20 Hz during an occultation measurement. GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 5 SOFIE CDR October 7-8, 2004 -5 System Requirements (cont) IDENTIFIER SHORT DESCRIPTION REQUIREMENT (Observational Views) SOF 180 Instantaneous Science FOV The SOFIE instantaneous science FOV shall be 6 arc minutes horizontal and 1.8 arc minutes vertical (defined as along the axis between Nadir and Zenith). SOF 295 Glint FOV The SOFIE glint FOV shall be 24 deg horizontal and 32 deg vertical. SOF 178 FOR The SOFIE steering mirror shall provide a field of regard of ± 2 º elevation and ± 2 º azimuth. (Pointing) SOF 300 SOFIE shall point the center of its FOV to ±1 arcminute at a fixed distance relative to the solar top edge centerpoint and maintain this position during occultation measurement. The pointing position will be considered "maintained" if a 10 Hz filtering (0.1 sec running mean) of the true pointing position varies <15 arc seconds (1 sigma) in elevation and <1.0 arcmin (1 sigma) in azimuth. Pointing Ability GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 6 SOFIE CDR October 7-8, 2004 -6 System Requirements (Cont) Table 2. SOFIE spectral band specifications and channel S/N requirements. SOF 174 : Measurement Bands SOF 183 : Radiometric SNR Band Center (m) Band Limits, m Band Limits, cm-1 S/N* O3 strong 0.290 0.2857 - 0.2941 34000 - 35000 1.0104 O3 weak 0.328 0.3226 – 0.3333 30000 - 31000 1.0104 particle strong 0.862 0.8475 – 0.8772 11400 - 11800 1.0106 particle weak 1.03 1.0101 – 1.0526 9500 - 9900 1.0106 H2O weak 2.45 2.427 – 2.475 4040 - 4120 2.5104 H2O strong 2.60 2.577 – 2.632 3800 - 3880 2.5104 CO2 strong 2.77 2.740 – 2.794 3580 - 3650 3.0105 CO2 weak 2.94 2.907 – 2.967 3370 - 3440 3.0105 particle strong 3.06 3.030 – 3.091 3235 - 3300 1.0105 particle weak 3.19 3.160 – 3.226 3100 - 3165 1.0105 CH4 strong 3.37 3.333 – 3.401 2940 - 3000 4.0105 CH4 weak 3.51 3.472 – 3.546 2820 - 2880 4.0105 CO2 strong 4.25 4.255 – 4.444 2250 - 2350 4.0105 CO2 weak 4.63 4.630 – 4.740 2110 - 2160 4.0105 NO weak 4.98 4.951 – 5.051 1980 - 2020 3.0105 NO strong 5.32 5.263 – 5.376 1860 - 1900 3.0105 *The effective noise bandwidth is 2 Hz. Band limits are given in different units (cm-1 = 10000/m) but are otherwise identical. GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 7 SOFIE CDR October 7-8, 2004 -7 System Requirements (cont) IDENTIFIER SHORT DESCRIPTION REQUIREMENT (Solar Tracking and Maneuvering) SOF 181 Altitude Range SOFIE shall be able to track the top edge centerpoint of the sun from an apparent altitude of 315 km down to the hard edge of the Earth during an occultation measurement. SOF 176 Scanning SOFIE shall provide the capability to vertically scan across the disk of the sun four (4) times after the sunrise occultation measurement and four (4) times prior to the sunset occultation measurement. SOF 304 Balancing SOFIE shall provide the capability to balance the ΔV signal (i.e. set Δ V to zero) using a gain setting (GA) to within 1000 counts. GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 8 SOFIE CDR October 7-8, 2004 -8 System Design GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 9 SOFIE CDR October 7-8, 2004 -9 Environmental Orbital Considerations Orbit - 600-650 km geocentric - Polar sun-synchronous - 2 year operational lifetime Thermal Predictions - Electronics Survival = -25 to +55 ºC - Electronics Operation = 0 to +50 ºC - Instrument Survival = -45 to +20 ºC - Instrument Operation = -40 to +20 ºC Radiation TID = 10 kRAD SEE = 37 MeV Atomic Oxygen Strongly dependent on altitude (600 km significantly less than 450 km). Using MgF2 protective coating on our steering mirror and primary/secondary Cassegrain telescope mirrors. Cleanliness Internal mirrors allowed to degrade (EOL, 26 months) to Level 500. This includes effects of micro-meteroids. GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 10 - 10 SOFIE CDR October 7-8, 2004 Design Description • • Instrument Unit – Purpose: • Perform science signal detection & FOV pointing and stabilization control – Contains: • Opto-mechanics – Mirrors, filters, beam splitters, field-stop, chopper • [1.8’ x 6’ Inst FOV; 32º x 24º Glint FOV] • Detector assemblies (includes TECs and PreAmps) • Steering mirror [4º x 4º FOR] • Sun sensor electronics and software [2º x 2º FOV] Electronics Unit – Purpose: • Perform system command and control, communication, signal conditioning, and power conditioning – Contains: • Command and data handling electronics and system software • Position and stabilization control electronics and software • Communication, signal conditioning, and mechanisms control electronics and software • Thermal sensor, TEC thermal control, and housekeeping electronics • Power conditioning electronics GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 11 - 11 SOFIE CDR October 7-8, 2004 System Block Diagram Spacecraft Deck Instrument Unit Steering Mirror Assembly Pinpuller Mechanism Steering Mirror Steering Mirror Positioning Sensor Electronics Solar Input Pinpuller Mechanism Sun Sensor Pickoff Mirrors Mechanisms Release Secondary Mirror Neutral Density Filter Spectral (700 nm) Filter Electronics Unit Primary Mirror Cassegrain Telescope Sun Sensor Baffle Mirror Amplifier Aperture Cover Field Stop Chopper Servo I/O Temp Sensors / Housekeeping 4 SWIR Bands (2.43 - 2.97 um) Beamsplitters C&DH Processor Focal Plane Array Chopper Control 4 UV,NIR Bands (0.29 - 1.03 um) Sun Sensor Processor Sun Sensor Housing Assembly Data Acquisition Power Conditioning and Distrubution 4 LWIR Bands (4.25 - 5.32 um) Channel Separation Module Assembly Individual Band Filters Temp Sensors Signal Conditioning & TEC Control 4 SWIR Bands (3.03 - 3.55 um) R a d i a t o r Detector Assembly (TEC, PreAmp) 1553 Interface Isolator Feet (14 ° Eff Wedge) Sensor Power, Mechanisms Power, and Thermal Sensors Survival Heater Power and Thermal Sensors 1553 Comm Bus GATS Spacecraft Bus Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 12 - 12 SOFIE CDR October 7-8, 2004 Spacecraft Configuration GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 13 - 13 SOFIE CDR October 7-8, 2004 Instrument Unit Radiator Pin pullers Aperture cover Steering mirror Alignment cubes N2 Purge Witness Mirrors (x4) Circular connector interfaces SC Isolator Feet (eff 14° wedge) GATS Dynamic Envelope: 16.2 x 26.3 x 29.5 inches Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 14 - 14 SOFIE CDR October 7-8, 2004 SOFIE Instrument Unit (cont) POINTING AND STABILIZATION CONTROL Sun Sensor SIGNAL DETECTION Channel Separation Module GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 15 - 15 SOFIE CDR October 7-8, 2004 SOFIE Electronics Unit Electronics PCBs Top Connectors and Cabling SC Radiator Panel Power Conditioning Dynamic Envelope: 16.2 x 26.3 x 29.5 inches GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 16 - 16 SOFIE CDR October 7-8, 2004 System Operation GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 17 - 17 SOFIE CDR October 7-8, 2004 Modes of Operation Survival GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 18 - 18 SOFIE CDR October 7-8, 2004 Modes of Operation (cont) Mode Measurements Commands Code Updates Survival Heaters Comments Science - Occultation - Housekeeping - System status 1. Real time processed 1. Timed not processed Processed ON Standby - Housekeeping - System status Real and timed processed Processed ON Safe - Housekeeping - System status Real and timed processed Processed ON SOFIE software can transition into this mode without a ground command but cannot transition out without a ground command Survival NA NA NA ON System power OFF GATS Peak data rate and power mode Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 19 - 19 SOFIE CDR October 7-8, 2004 Science Mode 17.77 DEG 21.57 DEG 650 Km X 473 km 315 km 24.85 DEG SOFIE IFOV (1.8' x 6') LAYER HEIGHT RESOLUTION = 25.75 m @ 0 km = 22.52 m @ 157 km = 18.63 m @ 315 km 158 km Z EARTH SUN SUN POINTING Orbital Characteristics 1. 600-650 km altitude 2. Polar sun-synchronous 3. SOFIE instrument pointed by SC to within ± 1º (3 sigma) of the solar vector during an occultation GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 20 - 20 SOFIE CDR October 7-8, 2004 Science Mode (cont) 315 km SOFIE Max FOR (4o x 4o) SOFIE IFOV (6' x 1.8') Sun disk (0.53o) Sun Sensor FOV (2o x 2o) EARTH Spectrum of the 16 bands (UV) O3 250 (NIR) Particle 850 H 2O 1600 2350 GATS (SWIR) Particle CO2 CH4 3100 nm (MWIR) CO2 3850 4600 NO 5350 Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 21 - 21 SOFIE CDR October 7-8, 2004 Science Mode (cont) States General Operations INIT Prepare system for occultation measurements •Synchronize electronics and software •Initialize timing and balance commands •Initialize tracking profiles AQR (15 seconds) Search and acquire sun on FPA •Find sun within FOR (if not found abort and return system error) •Position sun center at center of FPA •Begin fine tracking (arcsecond resolution) of sun •Position IFOV at desired offset from sun center Can overlap with DATA state DATA (~ 150 seconds) •Perform science channel measurements! •Maintain IFOV locked at desired offsets from sun center while following table driven profile (solar tracking) Fixed position Solar scanning (including azimuthal offsets) •Perform balance (set ΔV offsets) function •Save CO2 and balance data for post occultation analysis Can overlap with AQR state Maximum science measurement duration (AQR, DATA) = 155 seconds GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 22 - 22 SOFIE CDR October 7-8, 2004 Science Mode (cont) GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 23 - 23 SOFIE CDR October 7-8, 2004 Conceptual Science Mode Operational Profile Nominal Sunrise Science Occultation Measurement Profile Timeline Duration = 155 Seconds = 60 Seconds FOV Maneuvers +2 Degrees EL and AZ Searching Time = TB = 170 km Time = TFIN Time = TA AQR State …………. INIT State Time = T0.5 Time = 0 (Channel Measurements Begin) Nominal EL Scans Balance Time = TL DATA State = 15 Seconds Nominal Sunset Science Occultation Measurement Profile Timeline Duration = 155 Seconds = 60 Seconds FOV Maneuvers +2 Degrees Time = TFIN EL and AZ Searching Time = TB = 170 km Time = TA AQR State …………. INIT State Time = TL Nominal EL Scans Time = 0 (Channel Measurements Begin) = 15 Seconds Balance Time = T0.5 DATA State GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 24 - 24 SOFIE CDR October 7-8, 2004 Solar Acquisition and Tracking GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 25 - 25 SOFIE CDR October 7-8, 2004 Solar Scanning and Maneuvering Boresighting Vertical Scanning 1 degree (3 sigma) 10 arcminutes 12 arcminutes FOV 12 arcminutes 1 degree (3 sigma) 1 degree (3 sigma) 10 arcminutes Scanning 1 degree (3 sigma) Azimuthal Offsetting (bore sighting) Science Range SC Pointing Accuracy Capability GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 26 - 26 SOFIE CDR October 7-8, 2004 Science Data Products 2 1. Occultation (20 Hz) 1 -Solar edge locations (X,Y) -Solar vertical edge and center images -Steering mirror command and position (X,Y) -All channel sets (Strong, Weak, ΔV) -Time stamps (SC and relative) 1 2. Diagnostic (Limited) -Solar images -FPA frame images 1 El Az GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 27 - 27 SOFIE CDR October 7-8, 2004 Commissioning Phase WEEK 1 1. APPLY SURVIVAL HEATER POWER 2. APPLY SYSTEM POWER 3. EXERCISE BASIC COMM *APERTURE COVER NOT RELEASED 1 MONTH COMMISSIONING PHASE WEEKS 2-3 1. EXERCISE FULL COMM AND SYSTEM FUNCTIONALITY *APERTURE COVER NOT RELEASED WEEKS 4-5 1. RELEASE APERTURE COVER 2. PERFORM INITIAL SCIENCE AND CALIBRATION CHECKOUTS 3. VERIFY POINTING AND STABILIZATION CONTROL GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 28 - 28 SOFIE CDR October 7-8, 2004 System Technical Resources & Error Budgets GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 29 - 29 SOFIE CDR October 7-8, 2004 Technical Resources RESOURCE CURRENT BEST ESTIMATE REQ ID Mass 36.4 kg SOF 194 Envelope Controlled by MICD SOF 195 Average Power 74.1 W [56 W Electronics Unit, 18 W Instrument Unit] SOF 205 Peak Power 107.6 W SOF 206 Pinpuller Peak Power 32.2 W for < 0.5 sec, (130 mW Pre and Post Fire) SC ICD Survival Heater Average Power 15.2 W SOF 272 Survival Heater Peak Power 62.8 W SOF 272 Daily Data Volume 168 Mbits/day SOF 243 Resource margin and reserve managed by mission GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 30 - 30 SOFIE CDR October 7-8, 2004 Mass Budget SOFIE MASS BUDGET Instrument Unit Part / Sub-Assembly Steering Mirror Assembly Feedback Sensor Module External Cables and Connectors Electronics Unit Producer Vendor Vendor Vendor Mass (kg) 0.76 0.35 0.15 SDL 0.70 SDL SDL 0.25 0.05 Sun Sensor (Baffle & Optics) Assembly SDL 1.15 Optics Module Assembly Far Optics Module Assembly Near Optics Module Assembly Mid Optics Module Assembly SDL SDL SDL 1.60 1.60 0.20 SDL SDL SDL SDL SDL SDL SDL SDL SDL Vendor 0.75 2.05 0.95 1.40 0.65 1.45 1.60 1.75 0.10 0.60 External Cables 48-0167 Signal 1 48-0168 Signal 2 48-0169 Data Acquisition 48-0170 Chopper 48-0171 Sun Sensor 48-0172 Release 48-0173 Position 48-0174 Motors 48-0175 Heaters Internal Cables 48-0176 Signal 1 48-0177 Signal 2 48-0194 Data Acquisition 48-0195 Chopper 48-0198 Sun Sensor 48-XXXX Motors 48-0212 Heaters Survival Heaters Fasteners 0.05 0.40 SOFIE Insrument Unit Mass SOFIE Electronics Unit Mass SOFIE Conn, Fast, Cabling Mass CBE Total Mass Fore Optics Assembly Primary Mirror Spider Structure Secondary Mirror Structure Assembly Titanium Isolators Baseplate Lower Housing Aft Optics Bench Upper Housing Fore Optics Bench Aperture Housing Radiator Panel Witness Mirrors MLI Mechanisms Pinpuller Hinge SDL SDL Part / Sub-Assembly Structure PCB DC-DC Converters Motherboard Wedge-loks Producer SDL Vendor Vendor Vendor Vendor Mass (kg) 4.25 5.20 0.40 0.90 0.40 Connectors, Fasteners, Cabling Vendor Vendor Vendor Vendor Vendor Vendor Vendor Vendor Vendor 1.00 1.10 0.50 0.15 0.40 0.15 0.30 0.35 0.25 Vendor Vendor Vendor Vendor Vendor Vendor Vendor Vendor Vendor 0.40 0.40 0.15 0.05 0.10 0.05 0.05 0.10 1.20 18.56 11.15 6.70 36.41 Vendor Specification Model Prediction Measured GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 31 - 31 SOFIE CDR October 7-8, 2004 Power Budget SOFIE Orbital Power Budget Sub-Assembly 12VSM -12VSM 12V -12V 5V TE Coolers (3 stage) -65 C (Aver) TE Coolers (3 stage) -65 C (Peak) TE Coolers (3 stage) -40 C (Aver) TE Coolers (3 stage) -40 C (Peak) 6.30 6.80 0.62 5.75 0.62 5.75 2.28 3.15 2.17 2.80 4.30 5.50 2.60 5.00 1.75 2.67 Average Powers Peak Powers 0.62 5.75 0.62 5.75 9.83 12.55 6.97 9.20 5.00 6.00 1.90 2.50 0.65 0.90 0.89 8.21 0.89 8.21 14.04 17.92 9.96 13.14 CBE SC Bus Total Average Power CBE SC Bus Total Peak Power 3.00 4.00 1.30 1.80 0.50 0.60 0.03 0.04 0.40 0.50 3.00 4.00 5.90 6.60 9.08 11.21 10.00 12.00 12.20 13.40 12.97 19.59 14.29 17.14 17.43 19.14 0.70 Average Powers Peak Powers Average Input Protect Circ Power Peak Input Protect Circ Power 2.5V 7.00 8.00 Signal Cond. & Thermal Cont. (Aver) Signal Cond. & Thermal Cont. (Peak) Data Acquisition (Aver) Data Acquisition (Peak) Chopper Drive (Aver) Chopper Drive (Peak) Command & Data Handling (Aver) Command & Data Handling (Peak) Sun Sensor (Aver) Sun Sensor (Peak) Steering Mirror System (Aver) Steering Mirror System (Peak) Power Conditioning Efficiency 3.3V 2.8 4.2 74.11 107.57 Total Average SC Bus Elec Unit Power 56.34 Total Average TEC Power (W/O Converter Loss) 13.30 1. Average Power includes (Steering Mirror Peak Power)*(5.0 minutes/96 minutes) 2. Power conditioning efficiency based on an ~ 36V input GATS MEASURED Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 32 - 32 SOFIE CDR October 7-8, 2004 Orbital Power Profile Instrument Sub-system Time after passing over North pole (minutes) 40 45 50 55 Latitude (deg) 42.65 61.6 80.55 80.5 61.55 0 5 10 15 20 25 30 35 90 71.05 52.1 33.15 14.2 4.75 23.7 56.34 56.34 56.34 53 53 53 56.34 56.34 56.35 57 56.34 17.27 0.5 74.11 17.27 0.5 74.11 17.27 0.5 74.11 17 0.5 70.5 17 0.5 70.5 17 0.5 70.5 17.27 0.5 74.11 17.27 0.5 74.11 17.27 0.5 74.12 18 8.1 83.1 17.27 0.5 74.11 60 65 70 75 80 85 90 95 42.6 23.65 4.7 14.2 33.15 52.1 71.05 56.34 56.34 53 53 56.34 56.34 56.34 57 56.34 17.27 0.5 74.11 17.27 0.5 74.11 17 0.5 70.5 17 0.5 70.5 17.27 0.5 74.11 17.27 0.5 74.11 17.27 0.5 74.11 18 8.1 83.1 17.27 0.5 74.11 90 Orbit average SOFIE Electronics unit TECs (16) + Sun Sensor electronics Steering mirror Sub-total In eclipse = Removed from orbit average for 95 min orbits In eclipse 84 82 80 78 SOFIE 76 74 72 70 68 0 20 40 60 GATS 80 74.11 100 Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 33 - 33 SOFIE CDR October 7-8, 2004 GATS 9/17/2004 9/3/2004 8/20/2004 8/6/2004 7/23/2004 7/9/2004 6/25/2004 6/11/2004 5/28/2004 5/14/2004 4/30/2004 4/16/2004 4/2/2004 3/19/2004 3/5/2004 2/20/2004 2/6/2004 1/23/2004 1/9/2004 12/26/2003 12/12/2003 MBits/day 180 120 80 Date 160 140 100 60 Resource CDR/PDR Ratio Mass 36.4 / 34.6 = 1.05 Power 74.1 / 83.5 = 0.89 Data 168 / 73.6 = 2.28 9/8/2004 8/8/2004 7/8/2004 6/8/2004 5/8/2004 4/8/2004 3/8/2004 2/8/2004 1/8/2004 12/8/2003 11/8/2003 10/8/2003 9/8/2003 8/8/2003 7/8/2003 SOFIE MASS CBE TRACKING 6/8/2003 Watts 45.00 40.00 35.00 30.00 25.00 20.00 5/8/2003 1/ 1 2/ /200 1 3/ /20 3 1 0 4/ /20 3 1 0 5/ /20 3 1 0 6/ /20 3 1 0 7/ /20 3 1 0 8/ /20 3 1 0 9/ /20 3 10 1/2 0 3 / 0 11 1/2 0 3 / 0 12 1/2 03 /1 0 0 1/ /20 3 1 0 2/ /20 3 1 0 3/ /20 4 1 0 4/ /20 4 1 0 5/ /20 4 1 0 6/ /20 4 1 0 7/ /20 4 1 0 8/ /20 4 1 0 9/ /20 4 1/ 0 4 20 04 kg Resource Tracking SOFIE AVERAGE POWER CBE TRACKING 85.00 80.00 75.00 70.00 65.00 60.00 Date SOFIE DAILY DATA DOWNLINK VOLUME CBE TRACKING Date Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 34 - 34 SOFIE CDR October 7-8, 2004 Error Budgets BUDGET REQUIREMENT EXPECTED PERFORMANCE Radiometric WC Band 15 (NOWEAK) SNR = 3.0 x 105 SNR = 9.33 x 105 (Margin = 3.11) Pointing 15 Arcseconds (1 Sigma) over 0.5 seconds <1 Arcsecond (0.5 Arcseconds) Static Alignment 0.5 ° to SC 3 Arcminutes CBE Will be calibrated out on orbit! GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 35 - 35 SOFIE CDR October 7-8, 2004 Post-PDR System Changes GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 36 - 36 SOFIE CDR October 7-8, 2004 Changes since PDR SMA Caging Mechanism Removed Wedge Removed Radiator Reshaped Cable Ports Relocated GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 37 - 37 SOFIE CDR October 7-8, 2004 Changes since PDR (cont) Repositioned in SC and Radiator Removed Electronics Power Conditioning Redesigned Detector Packages now Non-hermetic GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 38 - 38 SOFIE CDR October 7-8, 2004 System Technical Risks GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 39 - 39 SOFIE CDR October 7-8, 2004 Technical Risks RISK ID = SOFIE_RISK_4 SOFIE depends upon an active pointing system to provide the required sun pointing accuracy and precision. The active pointing and control system algorithm may be unable to provide the required sun pointing accuracy and precision and the science capability would be degraded. CRITICALITY Green MITIGATION Extensive prototype and protoflight testing will be conducted. GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 40 - 40 SOFIE CDR October 7-8, 2004 System Technical Coordination GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 41 - 41 SOFIE CDR October 7-8, 2004 Technical Coordination – SDL Design Processes • • • Engineering Design and Development – System Design • QP0401 – Software Design • QP0406 Document Control and Configuration Management – Document Control • QP0501 – Software Configuration Management • QP0403, SOFIE Software Configuration Management Plan – SDL to maintain up-down information flow Waivers, Problem Failure Reports (PFR) – QP1301 GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 42 - 42 SOFIE CDR October 7-8, 2004 Technical Coordination – Internal Peer Review • • Review follows Breadboard/Prototype design phase – Includes SDL members both internal and external to SOFIE – System and component level Following review, design placed in configuration control GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 43 - 43 SOFIE CDR October 7-8, 2004 Technical Coordination – SDL Design Processes (cont) SOFIE GENERAL DESIGN STANDARDS Standards SOURCE PCB Design - IPC 2221, IPC 2222 PCB Fabrication - Class 3 of IPC 6011, IPC 6012, NASA GSFC S312-P-003 PCB Coupon Inspection - To be performed by customer SMT Assembly - NASA-STD-8739.2 Hand Soldered Assembly - NASA-STD-8739.3 Cable, Crimp, and Harness - NASA-STD-8739.4 Conformal Coating - SDL Internal Process ESD - SDL Internal Process Mechanical Torque - SDL Internal Process GATS MAP, GDRD MAP, GDRD MAP, GDRD SDL QW0915 SDL QP1503 SDL QW0914 Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 44 - 44 SOFIE CDR October 7-8, 2004 Documentation Status Document Status SOFIE Level 3 Requirements Mission Approved SOFIE Specifications Document Released SOFIE Flight Software Development Plan Released SOFIE Flight Software Specifications Released SOFIE Program Management Plan Released SOFIE Product Assurance Plan Released SOFIE Safety Plan Released SOFIE Contamination Control Plan Baseline Released SOFIE EEE and Materials Parts Lists Controlled. Initial lists submitted to Mission November 2003 SOFIE Risk Management Database Controlled SOFIE Calibration Plan Baseline Released SOFIE Integration and Test Plan Baseline Released SOFIE Software Design Document and Test Plan Baselines Released SOFIE Electrical/Software ICD Baseline Released Subcontractor SOWs and ICDs Released GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 45 - 45 SOFIE CDR October 7-8, 2004 SE Summary • • • Designs are mature and provide margin on system requirements Technical resources are being managed and tracked Error budgets are being managed GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 46 - 46 SOFIE CDR October 7-8, 2004 Supplementary Material GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 47 - 47 SOFIE CDR October 7-8, 2004 Radiometric System Requirements Table 2. SOFIE spectral band specifications and channel S/N requirements. SOF 174 : Measurement Bands SOF 183 : Radiometric SNR Band Center (m) Band Limits, m Band Limits, cm-1 S/N* O3 strong 0.290 0.2857 - 0.2941 34000 - 35000 1.0104 O3 weak 0.328 0.3226 – 0.3333 30000 - 31000 1.0104 particle strong 0.862 0.8475 – 0.8772 11400 - 11800 1.0106 particle weak 1.03 1.0101 – 1.0526 9500 - 9900 1.0106 H2O weak 2.45 2.427 – 2.475 4040 - 4120 2.5104 H2O strong 2.60 2.577 – 2.632 3800 - 3880 2.5104 CO2 strong 2.77 2.740 – 2.794 3580 - 3650 3.0105 CO2 weak 2.94 2.907 – 2.967 3370 - 3440 3.0105 particle strong 3.06 3.030 – 3.091 3235 - 3300 1.0105 particle weak 3.19 3.160 – 3.226 3100 - 3165 1.0105 CH4 strong 3.37 3.333 – 3.401 2940 - 3000 4.0105 CH4 weak 3.51 3.472 – 3.546 2820 - 2880 4.0105 CO2 strong 4.25 4.255 – 4.444 2250 - 2350 4.0105 CO2 weak 4.63 4.630 – 4.740 2110 - 2160 4.0105 NO weak 4.98 4.951 – 5.051 1980 - 2020 3.0105 NO strong 5.32 5.263 – 5.376 1860 - 1900 3.0105 *The effective noise bandwidth is 2 Hz. Band limits are given in different units (cm-1 = 10000/m) but are otherwise identical. GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 48 - 48 SOFIE CDR October 7-8, 2004 Radiometric Model Error Budget Steering Mirror Telescope Aperture Diameter = 10.2 cm Obscuration Diameter = 3.0 cm Entrance Pupil Area = 74.0 cm2 Entrance Pupil FOV = 9.14-7 SR Solar Input Telescope Aperture Diameter Aperture Cover Secondary Mirror Obscuration Diameter Primary Mirror Entrance Pupil Area Chopping Factor (Modulation Form Factor) = 0.4 Radiometric Electrical Signal Bandwidth = 2 Hz Radiometric Electrical Noise Bandwidth = 3.14 Hz Detector Area = 0.01 cm2 Cassegrain Telescope Field Stop 4 SWIR Bands (2.43 - 2.97 um) Beamsplitters 4 UV,NIR Bands (0.29 - 1.03 um) 4 SWIR Bands (3.03 - 3.55 um) 4 LWIR Bands (4.25 - 5.32 um) Optical Input Path Channel Separation Module Assembly Individual Band Filters Detector Assembly (TEC, PreAmp) NEP and SNR GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 49 - 49 SOFIE CDR October 7-8, 2004 Radiometric Model Error Budget (cont) Band Wavelengths = wavelengths corresponding bers of tableB 1 Band 1 Incident Detector Power = 1 1 0.294 0.286 1 0.011 1 1 3.8879·10 -6 2 0.333 0.323 2 0.017 2 1.0399·10 -5 0.877 0.847 3 0.305 3 4.1062·10 -4 4 1.053 1.01 4 0.409 4 5.2872·10 -4 5 2.475 2.427 5 0.614 5 6.5677·10 -5 6 2.632 2.577 6 0.596 6 5.8379·10 -5 7 2.793 7 0.617 7 4.8409·10 -5 3 2 2.74 Y 8 2.967 2.907 9 Band 16 System Transmittances = m 8 0.614 A 8 4.3974·10 -5 9 3.9877·10 -5 3.091 3.03 9 10 3.226 3.16 10 0.594 10 3.469·10 -5 11 3.401 3.333 11 0.581 11 3.196·10 -5 12 3.546 3.472 12 0.588 12 13 4.444 4.255 13 14 4.739 4.63 14 0.607 14 15 5.051 4.95 15 0.445 15 6.9515·10 -6 16 16 1.0554·10 -5 16 5.376 5.263 NEP = 0.639 2.566·10 -5 13 3.4048·10 -5 0.63 0.47 SNR = 1.718·10 -5 SN Margin = 1 1 1 9.844·10 -14 1 3.949·107 1 3.949·10 3 2 9.844·10 -14 2 1.056·108 2 1.056·10 4 3 2.953·10 -13 3 1.39·109 3 1.39·103 4 1.772·10 -13 4 2.984·109 4 2.984·10 3 1.79·10 -11 6 1.611·10 -11 5 3.669·106 5 146.771 6 3.624·106 6 144.958 7 6.329·10 -12 7 7.649·106 7 25.497 5 NEP 8 5.538·10 1 SR 8 7.941·106 Margin 8 26.471 9 1.477·10 -11 9 2.7·10 6 9 27.005 10 1.266·10 -11 10 2.741·106 10 27.407 11 1.042·10 -11 11 3.066·106 11 7.665 12 4.663·10 -12 12 5.503·106 12 13.757 13 5.212·10 -12 13 6.533·106 13 16.332 14 3.878·106 14 9.695 1.02·106 15 3.4 16 1.608·106 16 5.36 14 -12 4.43·10 -12 15 6.815·10 -12 16 6.563·10 -12 W 15 W System Transmittances includes a linear multiplication of appropriate mirror and filter transmittance, reflection, and absorption (due to end of life contamination) coefficients. GATS Optical Math Model Transfer Function Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 50 - 50 SOFIE CDR October 7-8, 2004 Radiometric Model Error Budget (cont) Electronics Path Phase Sensitive Detector (Synchronous Recitification) PreAmp Signal Conditioning SWITCHING DEMODULATION Front End BPF (1 kHz) LPF (12.8 Hz) G =1 G Balance Attenuation LPF (12.8 Hz) Demodulation and Signal Conditioning System Equivalent LPF = 10Hz A G = -1 Ground Processing (2 Hz Information Bandwidth, 3.14 Hz Effective Noise Bandwidth) Demodulated Signal Data Acquisition 1us Resolution Phase Reference Detector Channel Pair Detector Band A Chopped (1 kHz) Optical Input Signal Conditioning Optical Chopper (1 kHz) Chopper Reference Signal Phase Control Balance Attenuation Controlled Externally G Detector Band B 14-bit ADC Differential Amp LPF (12.8 Hz) LPF (2.15 kHz) MUX x1 u1 Chopper Drive Control 20 Hz Sampling Rate 32 X Oversampling Bit Resolution = 366uV LPF Settling to 12 RC Constants Front End PreAmp BPF (1 kHz) LPF (12.8 Hz) G =1 G Balance Attenuation LPF (12.8 Hz) A G = -1 SWITCHING DEMODULATION Signal Conditioning Demodulated Signal Phase Sensitive Detector (Synchronous Recitification) GATS Effective Sync Rect Q = 500 Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 51 - 51 SOFIE CDR October 7-8, 2004 Radiometric Model Error Budget (cont) Band / Detector Type 1 / PV 2 / PV 3 / PV 4 / PV 5 / PC 6 / PC 7 / PC 8 / PC 9 / PC 10 / PC 11 / PC 12 / PC 13 / PC 14 / PC 15 / PC 16 / PC SNR 3.14 Hz bw 5.81E+06 7.19E+06 8.38E+06 8.38E+06 3.59E+06 3.54E+06 6.79E+06 6.94E+06 2.65E+06 2.68E+06 2.98E+06 4.87E+06 5.39E+06 3.11E+06 9.33E+05 1.48E+06 GATS Required SNR 1.00E+04 1.00E+04 1.00E+06 1.00E+06 2.50E+04 2.50E+04 3.00E+05 3.00E+05 1.00E+05 1.00E+05 4.00E+05 4.00E+05 4.00E+05 4.00E+05 3.00E+05 3.00E+05 Margin 581.40 719.42 8.38 8.38 143.53 141.58 22.64 23.14 26.48 26.77 7.44 12.17 13.47 7.77 3.11 4.92 Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 52 - 52 SOFIE CDR October 7-8, 2004 Pointing Model Error Budget IDENTIFIER SHORT DESCRIPTION REQUIREMENT (Pointing) SOF 300 Pointing Ability SOFIE shall point the center of its FOV to ±1 arcminute at a fixed distance relative to the solar top edge centerpoint and maintain this position during occultation measurement. The pointing position will be considered "maintained" if a 10 Hz filtering (0.1 sec running mean) of the true pointing position varies <15 arc seconds (1 sigma) in elevation and <1.0 arcmin (1 sigma) in azimuth. GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 53 - 53 SOFIE CDR October 7-8, 2004 Pointing Model Error Budget (cont) • • 2D derived by hand, includes 1 mode in mirror and 1 mode in structure (4 plant states) Integrates OSC’s latest S/C model (from AIM Bus CDR) and SSG’s latest SMA model GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 54 - 54 SOFIE CDR October 7-8, 2004 Pointing Model Error Budget (cont) Error/Disturbance Source Sun Sensor Noise SMA DIT Sensor Noise SMA DIT Thermal Drift SMA Bit Resolution Timing Error S/C Disturbance Value 0.5 arcsec (1-σ) 0.2 arcsec (1-σ) 26.88 arcsec/ºC 0.7 arcsec 1 msec (1-σ) varies (see plot) Description White noise up to 2 Hz White noise up to 10 kHz slope 14-bit A/D White noise up to 50 Hz supplied by Orbital 25 20 15 S/C Motion (arcsec) 10 5 0 -5 -10 -15 -20 -25 0 5 10 GATS 15 20 25 Time (sec) 30 35 40 45 50 Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 55 - 55 SOFIE CDR October 7-8, 2004 Pointing Model Error Budget (cont) Description Two-D simple model with 4 states Jitter in Sun Elevation Position (arcsec, 1σ) Jitter in Sun Azimuth Position (arcsec, 1σ) S/C Reaction Torque in Elev. Plane (N-m, 1σ) 0.499 N/A 0.0001 GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 56 - 56 SOFIE CDR October 7-8, 2004 Alignment Knowledge Error Budget – SOFIE FOV to ROS Instrument Unit Optical Alignment Process Steering Mirror Assembly Steering Mirror Positioning Sensor Fix Steering Mirror, Telescoping, Mirrors, Filters, Field Stop, and Chopper Pinpuller Mechanism Steering Mirror ±10 mils = ±1 ArcMin Solar Input Pinpuller Mechanism Alignment Cube Sun Sensor Pickoff Mirrors Fore Deck Mid Deck Aft Deck Secondary Mirror ±15 mils = ±1.5 ArcMin Neutral Density Filter Spectral (700 nm) Filter Aperture Cover 7 ArcSec Resolution Primary Mirror Cassegrain Telescope Sun Sensor Baffle Co-Align Detectors and Sun Sensor with Pin Spot Source Field Stop Chopper Finish Instrument Assembly 4 SWIR Bands (2.43 - 2.97 um) ±25 mils = ±2.5 ArcMin Beamsplitters Focal Plane Array 4 UV,NIR Bands (0.29 - 1.03 um) Sun Sensor Processor Sun Sensor Housing Assembly Co-Align Detectors/Sun Sensor to Alignment Cube with Theodolites/Columated Source 4 SWIR Bands (3.03 - 3.55 um) 4 LWIR Bands (4.25 - 5.32 um) Channel Separation Module Assembly Individual Band Filters Detector Assembly (TEC, PreAmp) ±25 mils = ±2.5 ArcMin 15 ArcSec Resolution SOFIE Instrument Pointing Knowledge Budget Initial Mechanical Alignment due to Tolerancing 7.5 ArcMin Worst Case Alignment after Optical Alignment Process 22 ArcSec Worst Case Spacecraft Pointing Knowledge Requirements SOF231 The SOFIE optical axis shall be aligned to the spacecraft optical axis with an accuracy of ±0.25° prior to launch. This alignment will be maintained to within ±0.5° on orbit. From MRD SYS837 SOF292 The SOFIE reference axis alignment to the observatory reference axis shall be known to better than +/-10 arcsec. From MRD SYS753 GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 57 - 57 SOFIE CDR October 7-8, 2004 Alignment Knowledge Error Budget – Slow Thermal Dynamic Simulation of Hot Case Conditions • Assumptions – – Hot case thermal loads considered Restrained temperatures: • • • • • • • • • • – – – – CSM Assembly – 37 F to 48 F Radiator Interface – 24.5 F Aft Optics Deck – 30 F to 37 F Fore Optics Deck – 25 F to 32 F Bottom Deck – 32 F to 35 F Sun Sensor – 39 F to 43 F Mid Optics – 39 F M1 and Hub – 34 F M2 and Mount – 52 F Isolator interface at S/C – 86 F Only conduction heat transfer considered Steady-state temperature predicted Displacements from 70 F Displacements relative to Field Stop GATS Node Displacement (in) Rotation (Degrees) X Y Z X Y Z Mirror 81101 M2/SS1 -1.5E-3 -2.7E-3 -1.2E-3 -8.1E-5 -2.8E-5 -9.7E-6 106497 Chop -3.8E-4 4.0E-5 1.7E-6 -4.0E-6 -1.2E-6 -1.5E-5 106510 M3 1.7E-5 3.8E-4 -1.4E-4 -2.4E-6 -1.2E-5 7.0E-6 106520 Field Stop 0 0 0 0 0 0 107175 SS2 -3.0E-5 -1.1E-3 -1.1E-3 -8.1E-5 -3.2E-5 8.9E-6 116912 SS4 -2.4E-4 7.5E-4 1.9E-6 -7.8E-5 -3.9E-5 1.8E-5 116922 SS3 -1.1E-3 2.1E-3 1.7E-4 -1.2E-4 -4.3E-5 3.2E-5 Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 58 - 58 SOFIE CDR October 7-8, 2004 Alignment Knowledge Error Budget – Slow Thermal Dynamic Simulation of Cold Case Conditions • Assumptions – – Hot case thermal loads considered Restrained temperatures: • • • • • • • • • • – CSM Assembly – -27 F Radiator Interface – -35 F Aft Optics Deck – -26 F Fore Optics Deck – -31 F Bottom Deck – -30 F Sun Sensor – -27 F Mid Optics – -25 F M1 and Hub – -28 F M2 and Mount – -26 F Isolator interface at S/C – -4 F – – Only conduction heat transfer considered Steady-state temperature predicted Displacements from 70 F – Displacement relative to Field Stop GATS Node Displacement (in) Rotation (Degrees) X Y Z X Y Z Mirror 81101 M2/SS1 -1.1E-3 -1.4E-3 -2.5E-4 -1.4E-5 -1.5E-5 1.0E-5 106497 Chop -2.7E-4 2.7E-5 -1.8E-6 7.2E-6 -2.1E-7 -1.3E-5 106510 M3 4.5E-5 2.3E-4 -7.3E-5 -1.6E-5 -8.6E-6 -1.1E-6 106520 Field Stop 0 0 0 0 0 0 107175 SS2 -2.1E-4 -9.3E-4 -2.7E-4 -1.2E-5 -1.8E-5 1.8E-6 116912 SS4 -1.6E-4 5.4E-4 1.6E-5 -1.2E-5 -4.1E-6 -2.5E-6 116922 SS3 -7.9E-4 1.4E-3 2.0E-4 -2.1E-5 -4.3E-5 5.2E-7 Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 59 - 59 SOFIE CDR October 7-8, 2004 Alignment Knowledge Error Budget – Slow Thermal Dynamic Simulation of SOFIE to SC Deflections Node in center of Aperture Cover (SOFIE FEM coordinate system) Hot Case: Cold Case: Tx: Ty: Tz: Rx: Ry: Rz: Tx: Ty: Tz: Rx: Ry: Rz: GATS 3.03e-4 in -6.05e-3 in -8.46e-3 in -2.14e-4 degrees 5.39e-5 degrees -4.41e-5 degrees 6.00e-4 in -1.82e-2 in -1.99e-2 in -6.77e-4 degrees 6.92e-5 degrees -3.87e-5 degrees Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 60 - 60 SOFIE CDR October 7-8, 2004 Pointing Budget – SOFIE to SC Accuracy SOFIE Science FOV Boresight to Sun Center (SYS755) Required 60 RSS SOFIE Science FOV Boresight to ROS Error SOFIE ROS to S/C Deck I/F Plane Error CBE 0.4 (SOF231) Required 30 SOFIE ROS to S/C Deck I/F Plane Static Error SOFIE ROS to S/C Deck I/F Plane Slow Dynamic Error SOFIE ROS to S/C Deck I/F Plane Launch Shift CBE 1 CBE 2 CBE 2 S/C Deck I/F Plane to MRC Error (SYS837) MRC Pointing Accuracy (SYS844) Required 2 Required 17 ACS Accuracy (BUS272) Ephemeris Error (SYS844) Required 5 Required 36 RSS = 3 Arcminutes (3 Sigma) GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 61 - 61 SOFIE CDR October 7-8, 2004 GFOV Clearance 9.53in. Glint FOV 0.69in. GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 62 - 62 SOFIE CDR October 7-8, 2004 Level 3 & 4 Requirements Compendium GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 63 - 63 SOFIE CDR October 7-8, 2004 AIM Science Objectives Traceability to SOFIE Science Question 1. Morphology 2. GW Affects 3. Dynamics 4. H-chemistry 5. Nucleation Geophysical Parameters Required to Answer Science Question PMC Morphology, Particle Sizes PMC Morphology SOFIE Observation PMC Morphology PMC Morphology PMC Morphology Cloud Extinction Temperature Profile T,CO2 Profiles, Circulation Temperature Profile Temperature Profile CO2 Absorption H2O Profile H2O Profile, Circulation H2O Profile H2O Profile H2O Absorption CH4 Profile, Circulation O3 Profile O3 Absorption CH4 Profile, Circulation CH4 Absorption NO Profile GATS NO Absorption Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 64 - 64 SOFIE CDR October 7-8, 2004 Level 3 Requirements Management • • • • Requirements will be utilized as the main method for defining the functionality, performance, design constraints, and interfaces for the AIM program Requirements will be used throughout all phases of the program to guide design, development, integration, and test Requirements tracking and compliance assurance will be an integral part of peer, design, integration, and test reviews to insure that the system development is proceeding in accordance with the systems engineering and management process After initial completion, the requirements and interfaces will baselined and change tracking will occur: – Access control will allow those teams and individuals with responsibility for portions of the requirements to propose changes to those requirements. – The system engineering team will work with the necessary engineers and management personnel to access the impact of requirements changes on the remainder of the system. GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 65 - 65 SOFIE CDR October 7-8, 2004 Level 3 Requirements Management (cont) AIM Requirements Traceability & Specification Tree (from AIM SEMP) GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 66 - 66 SOFIE CDR October 7-8, 2004 Level 3 Requirements Management (cont) AIM Requirements Development Approach and Guidelines (from AIM SEMP) GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 67 - 67 SOFIE CDR October 7-8, 2004 Level 3 & 4 Requirements Management (cont) • • • • • SOFIE Level 3 requirements derived from AIM Level 1 & 2 requirements – Level 3 requirements report (DOORS) created in accordance with WBS – Approved by AIM Mission systems engineer and Deputy SE Level 3 requirements managed by SOFIE systems engineer – Level 3 requirements assigned to appropriate discipline leads Level 4 requirements derived from Level 3 requirements by systems engineer and discipline leads – Subcontractors requirements are also managed as Level 4 Level 3 and Level 4 requirements derivation includes source traceability and verification process information – Serves as Verification Matrix SOFIE Instrument Specifications and SOFIE Flight Software Specifications captured in SDL/04-004 and SDL/04-003, respectively GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 68 - 68 SOFIE CDR October 7-8, 2004 Level 3 Verification Matrix GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 69 - 69 SOFIE CDR October 7-8, 2004 Level 3 Verification Matrix (cont.) GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 70 - 70 SOFIE CDR October 7-8, 2004 Level 3 Verification Matrix (cont.) GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 71 - 71 SOFIE CDR October 7-8, 2004 Level 3 Verification Matrix (cont.) GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 72 - 72 SOFIE CDR October 7-8, 2004 Level 3 Requirements Database GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 73 - 73 SOFIE CDR October 7-8, 2004 Level 4 Requirements Database GATS Systems Engineering, SOFIE Chad PDRFish – October 22, 2003 74 - 74 SOFIE CDR October 7-8, 2004